Want Speed? Slow Down! 

Want Speed: Slow Down

Note: This is an updated version of the original 1982 article.

Training slow has always been considered a sign of weakness or laziness. However, if you want to run, bike, or swim faster, a successful and intelligent approach is to slow down! Along the way, you’ll get healthier, prevent injury and burn more body fat too.

Traditionally, it is thought that only anaerobic training – speed work – builds speed. However, developing the aerobic system first, before attempting hard work, is ideal: you get faster without the wear and tear – and injury – that often accompanies anaerobic training. Using a heart rate monitor, a basic biofeedback device, makes it even easier.

Heart Rate Monitoring

Despite the boom in heart monitor use by athletes, it is still a misunderstood training companion. (In 1982, heart rate monitors were virtually unheard of except in athletes I worked with.) While many athletes use these devices, they often don’t get their money’s worth from them. Today’s monitors are simple to operate, and are a valuable tool for developing the most important aspect of training – aerobic speed.

Heart rate monitors are really just simple biofeedback units. But without interpretation of the data they provide – heart rate changes – their true benefits cannot be realized. Dorland’s Medical Dictionary defines biofeedback as “the process of providing visual or auditory evidence to a person of the status of body function so that you may exert control over that function.” In practical terms, using a heart monitor to control workout pace can help build aerobic speed, improve overall health and burn more body fat.

As a student in the 1970s, I was involved in a biofeedback research project that measured heart rate changes in humans subjected to various physiological inputs, including running. Once in clinical practice, it became evident that using the heart rate to objectively measure aerobic function was extremely useful. This began a long process of clinical research (which continues today), and the development of techniques that help improve human performance on all levels.

By the early 1980s, all the athletes I trained used heart monitors. These were cumbersome but accurate, and unlike today’s monitors were large, bulky and not made for athletes but cardiac and other inactive patients. (While more user-friendly, modern monitors still use old technology.)

Working with beginner to professional athletes in all sports, I developed applications for heart monitor use in three key areas: 1) training, 2) self-assessment and 3) competition.

Training

During training, a heart monitor can help athletes develop their body’s aerobic system, which includes the red, aerobic, “slow twitch” muscle fibers. This process is referred to as building an aerobic base, and is the foundation of good endurance. Especially important, as outlined below, is for each person to find their specific training heart rate that will allow this optimal aerobic development.

Building a great aerobic base is accomplished by training exclusively aerobic for a certain number of weeks and months. During this period, anaerobic workouts (including higher heart rate training, competition and weight work) should be avoided. Anaerobic activity can actually impair the aerobic system, therefore, each workout during aerobic base training should be only aerobic.

The aerobic system plays a vital and primary role in all physical activity. For example, between 95 and 99% of the energy used for endurance sports, including competition, is derived from the aerobic system. This is true for events lasting more than a few minutes, and races from the mile to the marathon, and beyond. In addition to the traditional endurance events such as running, biking and swimming, aerobic-based sports also include tennis, golf, basketball and most others.

There may be several physiological reasons why anaerobic workouts can reduce aerobic function:

  • Anaerobic activity can lower the number of aerobic muscle fibers, sometimes significantly. This can happen in just a few short weeks of anaerobic training.
  • Lactic acid, produced during anaerobic work, may inhibit aerobic muscle enzymes necessary for aerobic function.
  • Anaerobic training increases the respiratory quotient (a measure of fat- and sugar-burning) indicating the body is burning less fat.

Excess stress in any form (mental, physical or chemical) can inhibit the aerobic system due to increases in the stress hormone cortisol. Just as important is that carbohydrate consumption can increase insulin levels, and impair fat burning and increase reliance on sugar. These topics have been discussed elsewhere.

Building a great aerobic base takes at least three months. For athletes who have lost their competitive edge, have chronic injury or ill health, have difficulty burning body fat, or are just starting an exercise program, a longer base period – up to six months or more – may be needed. Some athletes have learned that training aerobically is all they need to compete better than ever.

This approach is sometimes difficult initially for athletes because in almost all situations training at the prescribed level is painfully slow. In addition, there may be a social issue as your training partners may want you to work harder. And, because a normal 5-mile run, for example, will take a longer period of time at a slower pace, instead of “miles” it’s best to workout by “minutes.” Our athletic culture is still entrenched in the myth of “no-pain, no gain” making proper training a mental challenge at times. But serious training requires discipline. Hang in there: improvements in speed, health and fat burning are on the way!

What’s the best heart rate for aerobic training? The answer to this is individual, and key to building a great aerobic body. Many are familiar with the old heart rate formula: 220 minus your age, multiplied by 65% to 85%. But this method has no scientific or clinical basis. For example, an individual’s maximum heart rate is supposed to be represented by 220 minus the age. However, if you’ve ever pushed yourself on the track or in a race to find your highest heart rate, it may not be close to this formula as more than half of the population finds. Then there’s the percentage factor: which do you use – 65%, 75%, 85%? That’s an extremely wide range, and impractical. Rather than guess, use a scientifically-based formula.

One effective way of finding an optimal heart rate for aerobic training—called the maximum aerobic heart rate—is to evaluate certain physiological parameters on a treadmill, such as respiratory quotient versus heart rate. Seeing the success of this approach, I ultimately found a simple mathematical formula that predicts the same heart rate (typically within one or two beats), and in the early 1980s began using this 180 Formula. (Treadmill testing is still ideal but not readily available, and is relatively expensive.) One unique feature of the 180 Formula is individualization – the person’s general health status is factored into the equation, something automatically incorporated into treadmill testing, but not part of other formulas.

The 180 Formula

To find your maximum aerobic heart rate:

  1.   Subtract your age from 180 (180 – age).
  2.   Modify this number by selecting a category below that best matches your health profile:

a.     If you have, or are recovering from, a major illness (heart disease, high blood pressure, any operation or hospital stay, etc.) or you are taking medication, subtract an additional 10.
b.     If you have not exercised before or have been training inconsistently or injured, have not recently progressed in training or competition, or if you get more than two colds or bouts of flu per year, or have allergies, subtract an additional 5.
c.     If you’ve been exercising regularly (at least four times weekly) for up to two years without any of the problems listed in a or b, keep the number (180 – age) the same.
d.    If you have been competing for more than two years duration without any of the problems listed above, and have improved in competition without injury, add 5.

For example, if you are 30 years old and fit into category b:
180 – 30 = 150, then 150 – 5 = 145.

During training, create a range of 10 beats below the maximum aerobic heart rate; in the example above, train between 135 and 145 staying as close to 145 as possible. To develop the aerobic system most effectively, all training should be at or below this level during base building. As the aerobic system develops, you will be able to run faster at the same maximum aerobic heart rate.

Once a great aerobic base is developed, an athlete can develop anaerobic function, if desired. In some cases this may not be necessary or the time and energy is not available for such endeavors. (Successful anaerobic training can be accomplished in a relatively short period of time, a topic discussed in my book, Training for Endurance.)

One other significant benefit of applying the 180 Formula is the biochemical response: production of free radicals is minimal at this training level compared to training at higher heart rates. Free radicals contribute to degenerative problems, inflammation, heart disease, cancer and rapid aging.

As important as finding the correct aerobic training heart rate is the process of self-assessment.

Self-Assessment: The MAF Test

A significant benefit of aerobic base building is the ability to run faster at the same effort, that is, at the same heart rate. A heart monitor can help objectively measure these improvements using a test I developed in the mid 1980s called the maximum aerobic function (MAF) test.

Perform the MAF Test on a track, running at the maximum aerobic heart rate. A one- to five-mile test, with each one-mile interval recorded, provides good data. The test should be done following an easy 12–15 minute warm up, and be performed about every month throughout the year. Below is a 5-mile MAF Test of a runner training at a heart rate of 150:

Distance   Time (min:sec)
Mile 1    8:21
Mile 2    8:27
Mile 3    8:38
Mile 4    8:44
Mile 5    8:49

During an MAF Test, it is normal for the running times to slow each mile – the first mile should be the fastest and the last the slowest. If this is not the case, it may indicate the lack of an effective warm up. In addition, the test should show faster times as the weeks and months pass. For example, over a four-month period, we can see the endurance progress in the same runner from the above MAF Test. Note the aerobic speed improvement between April and July:

April   May    June    July
Mile 1    8:21     8:11   7:57    7:44
Mile 2    8:27     8:18   8:05    7:52
Mile 3    8:38     8:26   8:10    7:59
Mile 4    8:44     8:33   8:17    8:09
Mile 5    8:49     8:39   8:24    8:15

This improvement is typical during the aerobic base period. Some improve at a faster rate, others slower. Most importantly, if you’re not improving within a three- or six-month period, it means something is wrong. It may be a dietary or nutritional factor, excess stress, overtraining (such as too many miles), etc. In some cases, it may be the maximum aerobic heart rate is too high (often from choosing the wrong category in the 180 Formula). Moreover, a reversal of aerobic function, i.e., slowing of aerobic pace during base training, may indicate an impending injury – enough of a reason to perform the MAF Test regularly.

Progress should continue in some form for three to six months or more before aerobic benefits may reach a normal plateau. Adding anaerobic work to the schedule before this plateau may impair (and ultimately even reverse) further aerobic progress.

The greatest benefit of the MAF Test is that it objectively demonstrates aerobic improvement in the form of aerobic speed. These changes also reflect competitive improvement.

Competition

A direct relationship exists between the maximum aerobic pace (as measured by the MAF Test) and competition. Essentially, increasing aerobic function improves competition (recall that events lasting more than two minute’s duration obtain most energy from the aerobic system).

Data gathered on hundreds of runners I trained over a period of several years showed that the MAF Test was positively correlated with race pace – as the MAF Test improved, so did competition. The chart below, based on actual MAF Tests and 5 kilometer running race times, demonstrates this relationship.

MAF            5K             5K
Min/Mile    Race Pace     Time
10:00             7:30          23:18
9:00             7:00          21:45
8:30             6:45          20:58
8:00             6:30          20:12
7:30             6:00          18:38
7:00             5:30          17:05
6:30             5:15          16:19
6:00             5:00          15:32
5:45             4:45          14:45
5:30             4:30          13:59
5:15             4:20          13:28
5:00             4:15          13:12

The above runners included those who developed an aerobic base, and raced on a flat, certified road course, or track. Most did not perform any anaerobic training, and for most, this was their first competition of the spring or fall racing season. Moreover, 76% of these athletes ran a personal best time for this distance! Similar relationships exist for longer events and for other sports.

The use of a heart rate monitor takes the guess work out of training and can help increase aerobic speed. It can also help prevent injury, ill health and burn off excess body fat.

Join the discussion 129 Comments

  • Jon says:

    Hi Phil,

    I have come across your method in the last week and started training to the 180 method. I have found a can’t keep my cadence at 90 now, whereas this was always consistent before. To keep my heart rate down I need to be around 80 cadence. Is this normal and do I not worry about cadence at this time?

    • Rick says:

      I’ve just started this method recently and found the same thing. My HR rises quickly when keeping my cadence at 90. Have you found that you were able to increase you cadence again after following the method for some time?

      Thanks, Rick

  • […] yesterday 5:53. Run/Thoughts: I start very slow, my heart bit hardly goes about 120, so I stick to MAF (140 max) rate, but not because I decided, as I tried MAF method ones and just found it too boring […]

  • ken says:

    I’m 68 and my HR would be112. When I run 7 tempo runs do use same HR. thanks

  • Van says:

    Hi,
    I just want to point out a typo in the text: “This process is referred to as building anaerobic base” … of course you mean an “aerobic” base.
    Regards,

  • Brian says:

    Hi
    I tried my first MAF test today @HR 140 and ran 10.30/mile on a track.
    My HR max is 193 (max measured on a fast run). I’m 38 have had Achilles issues last 18 months but have been able to run most of the time. I wasn’t sure to take off 5 or not so I put my max aerobic HR at 140. Which felt easy and SLOW!
    I trained for my first half marathon 3 months ago mostly between HR145 / 155 with an average pace of about 9:15min/mile. I completed the half (which was very hilly) in 8min/mile (1hr:47min) @HR172.
    My Question is if I can run about 5 or 6 hours a week exclusively at MAF 140 for next 6 months am I likely to improve much? My main goal is a sub 20 5k. I did 21:35 this time last year and didn’t start any of my 3 5k planned attempts since as I kept irritating my Achilles when i upped the speed.
    I now realise I was ramping up my speed work to quickly and not enough aerobic base?

    • Brian:

      Generally speaking, yes. But do a MAF test each month. If your aerobic speed does not increase appreciably, it’s not because the system “doesn’t work.” Aerobic function only happens when you are not under chronic stress, so, if you don’t see results, look for a bottleneck to your athletic development: there’s something in your lifestyle (work, sleep, stress), nutrition, digestion, immune function, or even body mechanics that is upping the stress and not letting you run aerobically, even when you’re at or under your MAF heart rate.

      In other words, the MAF test works both ways: not only does it tell you that your aerobic function is improving, but it also tells you that if it doesn’t improve, a lack of aerobic function isn’t the only thing wrong with your situation.

      As far as your achilles tendon situation, increasing speed work quickly does that. However, the Achilles doesn’t get irritated “just because.” Specifically, the achilles (and every other tendon in the body) has to track back and forth in a straight line. If not, it rubs up against other structures (bones, tendons, muscles) and that’s when it gets irritated. So, most likely what happened was a greater-than-ideal increase in speedwork along with some preexisting muscular imbalance. Particularly, look at your knee’s ability to flex and extend, as well as the ability of your frontal calf muscles (particularly the peroneal muscles) to supinate and pronate your foot.

      How does the biomechanical problem compound with the excess increase in intensity? If you are under more stress, your muscles are tighter, which means that if there’s an imbalance, that imbalance is going to show up in a bigger way. If muscles are more relaxed, there is more movement happening, which means that your body has greater opportunities to learn how to move well and correct the imbalance spontaneously.

      • Brian o Leary says:

        Thanks Ivan,
        That all makes sense. Looking at the Achilles as my body trying to teach me something rather than the annoyance it’s been will no doubt help. Working on my squat and ankle/foot strength and flexibility is part of my plan so hopefully I come back with some good numbers in 6 months.
        Thanks again.

  • Kevin says:

    My question is whether the competition numbers (MAF min/mile) were taken from a one mile MAF test or an average of a five mile test or somewhere in between.

  • Matt says:

    I’ve just started the aerobic training plan. If I am expected to plateau in aerobic progress after about 6 months, then what is the long-term plan for progressing in aerobic fitness? How does an athlete typically overcome this plateau and continue to progress in improving their MAF pace? Thanks.

    • Matt:

      Check out the articles in the methods section. I’ve written extensively in the comment threads about how to use MAF beyond aerobic base-building. I’d be more than happy to answer any outstanding questions that might remain. Thanks!

      • Matt says:

        I found this: “You aren’t supposed to train at MAF only, all the time. You are supposed to train at it for 80% of your total volume, and train anaerobically the rest. That’s plenty of strength training and intervals. (You only train 100% MAF when you are aerobic base-building, ill, injured, overtrained, or recovering from any of the 3.”

        It’s definitely helpful and perhaps the answer to the question as well, but I’d like to clarify. I’m guessing that after spending time (it’ll probably be at least 6 months for me) building an aerobic base, and assuming no injury, overtraining, etc, then doing 80% MAF heart rate and 20% anaerobic heart rates is what helps a person keep from plateauing in their MAF pace? Is that it, or is there more to it? Thanks.

        • Matt:

          People shouldn’t plateau at their MAF pace for a very, very long time. Years. The 6-month mark is when you can be reasonably certain that your aerobic base is developed enough to safely incorporate a significant amount of anaerobic work.

          What you are training at the MAF pace is literally your ability to break down and burn fats. This ability will just grow and grow the more you use it, and will facilitate the use of your muscles in sustained endurance events. In a very real way, it’s not your muscles that you’re training here (although they of course, do grow with this and they play an important role). The first and most important thing that you’re training is the amount of trucks, so to speak, that are going from your fat-storage warehouse to your fat-burning factories, and at which rate they are going. If supply increases, demand—the density of fat-burning factories across your body—also rises. (Which is how the development of your muscles occurs). The amount of trucks and the amount of factories can be expanded to amazing levels without a shred of anaerobic work. I like to say that it’s this aerobic fat-breakdown capability that should take 90% of us down to 7 minute miles, and 9% of us down to 6 minute miles.

          The reasons most people plateau in aerobic development is for other reasons: a nagging muscle imbalance may mean a huge power leak, which makes it very metabolically costly to go beyond a certain speed, or the stress of the muscle imbalance itself is enough to raise the heart rate and reduce aerobic function. Bad sleep, bad nutrition, can all contribute to aerobic dysfunction (and therefore a lack of aerobic development).

          As long as you treat the aerobic engine right, and facilitate its use, you can use it to go very, very fast.

          There’s a lot more in the comment threads, but if I haven’t answered your question, please ask again.

  • Joe says:

    Is my Aerobic Heart rate too low? Based on the formula I should be running at 136 or lower which results in a 12 minute mile. I am currently running a 7:12 mile at 180BPM when I race in 5ks. The chart above indicates my mile pace should be around 9:30. I do not meet the criteria for increasing by 5 Bpm due to ACL surgery in April 2013 and some calf problems that arose from transitioning to low drop sneaker too quickly.

    • Joe:

      That’s a sample chart, I think from aerobically-developed athletes. Training at an aerobic pace doesn’t increase your maximum speed like speedwork will, but what it does do is help you be able to metabolically (read:aerobically) sustain a higher speed, i.e. a higher percentage of that max power.

      This means that the chart you mention is an example of what your speed should look like once you’re aerobically developed. Specifically, your aerobic speed and your maximum speed should converge somewhat. For example, while I can run a 18 min (ish) 5K, I’m doing 9 minute aerobic miles. In other words, I’m not nearly as aerobically developed as I should be, given my present maximum power.

      I’m not exactly sure where the data is from, but I wouldn’t reverse-engineer my MAF heart rate from the data. Instead, play conservative. (Furthermore, 5 adding beats per minute may win you a few seconds, but not a few minutes).

  • Tina says:

    Hi!!

    I just bought the big book and have been reading it daily. I’ve done the math and am now trying (it’s very difficult to run so slowly) to stay near my max HR of 137. With winter around the corner I will be looking to move inside for my training on the treadmill. Will this need to be tweaked in any way (such as a higher HR, % raise incline etc) for me to keep training in order to build my aerobic base? Or will moving inside hinder my progress in any way? I’m just into my first month of using the formula and don’t want to take away from progress by utilizing a treadmill as opposed to running the road. Thank you for any information you can provide!

  • Jonathan says:

    My MAF HR is 158bpm. What would you estimate my marathon race pace heart rate to be?

    Earlier on in the week I did an experimental tempo run for ~100mins with my HR around 175-176bpm for the first hour. After 1 hour I noticed my HR drop to 171-172bpm, even though my pace stayed the same (~7:30/mile). Why is that?

    Also, although I felt fairly strong physically, it definitely started becoming a mental challenge after 70-80mins or so. I also felt like, if I had to go for 3hours at this HR, I’d need to strategically fuel up every 45-60mins, otherwise I’d probably fade. For this run I didn’t even have breakfast and didn’t have anything during the run either.

    • Jonathan:

      Try 5-10 BPM above MAF. Generally speaking, this should be some 15-30 seconds faster than your MAF pace. The reason that your heart rate tends to drop after a while is because (1) you relax into a run, and (2) your body keeps increasing the activation of your aerobic base as you go along. (Of course, at some point your aerobic base is going to get tired and you’ll see your heart rate increase again).

      • Jonathan says:

        Hi Ivan.

        I did an 82min (10.4mile) run with my HR settling around 163bpm (MAF+5bpm) today. I felt really strong, and think it would be a “safe” marathon pace. I actually felt just as aerobic at 163bpm as I do 158bpm, though how it feels is not always the same each day.

        I think 168bpm (MAF+10bpm) is doable, possibly even 173bpm (MAF+15bpm). I guess if I was doing suitably higher mileage/hours per week, and did some specific marathon training, the 173bpm figure would be doable!

        MAF+(5-15bpm) is pretty useful!

        What’s interesting is that there is a much bigger difference between half marathon HR and marathon HR, at least for the non-elite performances. For instance I feel like my half marathon HR would be around 180bpm (which is a “fast” pace for me), but 168bpm (which feels considerably lower in intensity) could be a struggle for a full marathon.

        Thanks.

        • Jonathan:

          Glad you’ve found this helpful, and you bring up a good point: the reason that elites have a much more similar half-marathon and marathon HR is because the aerobic system of elites is so much more powerful, relative to their own anaerobic system, than the aerobic system of non-elites. (Typically, the anaerobic system of non-elites just outclasses their aerobic system). So, not only can elites (1) go very fast at a lower heart rate, but (2) they also don’t have the anaerobic machinery to sustain a high heart rate for a long period of time (which is why their heart rate is so consistent.

          Don’t get me wrong—elites are very powerful—it just so happens that most of their power comes from aerobic machinery.

      • Jonathan says:

        I forgot to add. My last MAF test showed an 8:19/mile average (though I may have improved since then). Today at MAF+5bpm I showed a 7:55/mile average, so 24s/mile faster.

          • Jonathan says:

            Do you think doing a job where you’re on your feet and moving around a bit can improve fitness? I’ve been doing 48hours per week in a warehouse type of environment. Nothing strenuous though, mostly walking around or doing light things. The reason I ask is because this week I’ve experienced a sudden increase in fitness this week, for all of my runs (MAF, tempo and threshold).

            Today (13th December) I did 78mins/10.3miles @ 7:36/mile with my heart rate warming up to MAF and staying there (except for a few miles in the middle, where it went about 2bpm above MAF). Either way, that’d correspond to a MAF pace of 7:4X, which is a big shock for me! (For comparison, on 30th October I did 83mins/10.0miles @ 8:19/mile at MAF.)

            Also, usually I do a weekly 40-50min tempo run with the HR at settling around 173-175bpm. From the beginning of October to the end of November, my pace has gradually/slowly improved from 7:31/mile to 7:17/mile. But this week I did 50mins/7.1miles @ 7:02/mile! And not just that, it was with the HR barely reaching 168-170bpm!

            4 out of 5 of my runs have been like this all week. At first I thought something was wrong, but the perceived intensity and everything feels correct. The tempo run felt easier than usual (as it should – about 5bpm lower than usual), the aerobic run felt like I was so light and floating (as it should – faster pace than ever (for me), and same heart rate as before).

            I was thinking that a slightly higher than resting heart rate for a lot of the day could be having a “low aerobic” type of fitness boost for me. Apart from this work, I can’t think of anything else that I’ve changed in my daily routine. Either way, hopefully it continues!

          • Jonathan:

            The answer is absolutely yes. In fact, the reason that most hunter gatherers tend to be so aerobically fit is because they spend a lot of their time foraging—on their feet, doing easy work. Training isn’t just the time you deliberately go running or to the gym. For example, I walk 45 minutes to get to the gym and back. That counts.

            Excellent progress, by the way!

            You seem to have the aerobic training part dialed. But there are other areas that you can also address: anything that reduces stress (better nutrition, better sleep, fewer chemicals around you) also increases aerobic function, essentially making the aerobic system more “trainable.”

  • […] well; I like to run at that pace though I haven’t been doing it lately. If you’re doing MAF training you’ll likely want that one, and though you should verify it with a heartrate monitor that […]

  • Peter Rosenthal says:

    I just started training with the Maffetone method and recorded three mile splits at a 135 HR (I am 45 years old) of 11:18, 11:40 and 11:58. I recently ran a marathon and averaged 9 minutes per mile for the race. I assume this means that I have a lot of work to do to improve my aerobic base and that I ran the marathon in a more anaerobic state, which is not ideal. Is that correct?

  • Jonathan says:

    I’m planning to do some more experimental runs in the future. What HR range would you say corresponds to the half marathon and marathon? I know you’ve mentioned it a few times, but just wanted to confirm them again! Cheers.

    • Jonathan: For the marathon and half-marathon we’re talking about 5-10 BPM above MAF and 10-15 BPM above MAF, respectively. However, it’s always best to test this out since this can vary quite a little bit between individuals.

      • Jonathan says:

        Thanks Ivan! It’ll be interesting to compare with the expected values.

        This has actually got me thinking about something else. When I first started, my HR would easily go sky high at any chance it could. Whereas now, as I’m getting fitter, it actually requires a conscious effort to push the HR up. And I feel like my HR is now a more true relation to my “exact” effort level. Not that it wasn’t before, but it felt like my HR could spike easily before.

        The first example that comes to mind is from before I got into MAF training. I did a threshold heart rate test and it suggested I could sustain ~187bpm for an hour in a race. And I probably could at that time. But if I was to do a threshold run now (with better fitness), my HR would only reach ~181bpm at that same “1 hour race” effort, so a good 6bpm less. But the only reason I think I could’ve sustained 187bpm in the past is because I was in that unfit state where HR goes through the roof no matter what. Now it’s like more “true” to the effort? It’s like, the faster and fitter you get, the tougher/truer the HRs become, since your muscles are working more to keep up the pace/effort?

        So I’m guessing MAF+(5-10) and MAF+(10-15) for half and full marathons would/should be really accurate for “fit” runners, but necessarily for those in my previous unfit state! It’s only a few months ago that I would’ve thought those expected values would be far out, but they’re starting to become more and more true as I progress.

        It’ll be interesting to hear your thoughts!

        • Jonathan:

          About effort: yes, but I wouldn’t talk about it in terms of “true” effort.

          Our “perceived exertion” and our heart rate actually measure two different things: the heart rate is a measure of how much energy the metabolism is producing relative to its total ability. Perceived exertion, on the other hand—what we call “effort” is a measure of how much of our total muscle power we’re using. When, for example, we have very powerful muscles relative to our metabolic power, our heart rate rises very quickly even when our perceived effort does not.

          This, for example, is the case with sprinters: the amount of energy their muscles can consume far outpaces the ability of their metabolism to produce it. That’s why Usain Bolt will finish his 200m sprint and be unable to run again afterwards, but he doesn’t look exhausted. His muscles are extremely powerful and would be capable of running again and again—had the metabolism been able to provide them with energy.

          Just look at Usain Bolt’s face as he’s crossing the finish line: he’s working hard, but his features look very relaxed: even though he can’t produce enough energy to go any faster than that, he isn’t going anywhere near the upper limit of his muscles’ contractile ability.

          The ultrarunner is in the opposite situation: an extremely powerful metabolism but muscles that can only use a small percentage of that huge metabolism at any given time. For that ultrarunner, getting their heart rate is a really difficult task: their muscles just can’t consume energy that quickly. However, even when they’re going relatively slowly, they may be feeling like they’re running hard: their muscle contractions may be very close to the upper limit of what their muscles can produce.

          So, both the heart rate and the perceived exertion each tell you something different about the body, and when put together, they tell you what kind of athlete you’ve developed yourself into. The fact that Usain Bolt can max out his heart rate (use up his metabolism) without feeling a lot of effort (muscles aren’t working hard) doesn’t mean he’s a bad athlete—it just means he’s a sprinter.

          • Jonathan says:

            Hey Ivan. Ah yes, of course, I completely forgot about that!

            I have another question about my current situation. Ever since 3 weeks ago, where I did that amazing breakthrough 10 mile run at 7:36/mile (with some miles 1-2bpm above MAF), things haven’t been so plain-sailing. My pace/HR have been going in the wrong directions, and I’ve not felt that good as a whole. Last week I did a 52min tempo run at 6:56/mile, and on this Monday I did a 20min threshold run at 6:32/mile (awesome), but yesterday was a disappointing run (very high HR and bad pace), so I wasn’t expecting much today. Anyhow, I decided to do a MAF test today as there was no wind. I did just over 4 miles @ 8:10/mile, with my heart rate 1-2bpm above MAF for quite a bit of it again (I struggled to keep it down). At the end of October I did 8:19 at MAF, and at the beginning of November I did 8:22 at 1-2bpm below MAF. So barely an improvement. But what disappoints me most was how far away from 7:36 I was today. I was honestly expecting 7:50 at the worst. But 8:10 was poor. My perceived effort was low as well, implying that my muscular power is still better than my aerobic system.

            My suspicion, and I’ve suspected this for a while now, is that I might be overreaching and doing too much anaerobic work. From September to December I was doing approximately 4 hours of running each week, which eventually started including two anaerobic runs: one of them 20-25mins at threshold, the other 40-50mins at tempo. That’s a good 25-32% of anaerobic work, which is 5-12% above the recommended 20% I’ve seen on here. It hasn’t affected me for months, and I’ve made great progress both aerobically and anaerobically, but perhaps it’s catching up with me? The weird thing is that my tempo and threshold runs have been brilliant lately. There’s no way I was anywhere near 6:32 threshold and 6:56 tempo pace back in October/November. So perhaps my current dip in aerobic performance is just an anomaly?

            Either way, my plan going forward is to consistently do around 3-4 hours per week, but adhere more strictly to the 20% recommendation this time around. This leaves me with 36-48mins of anaerobic work each week. I’m thinking of making my week something like this:

            •3x 40mins at MAF
            •1x 80mins at MAF
            •1x 40mins at tempo/MAF+10bpm (Somewhere between marathon and half marathon.) (Other times I might do 20-25mins at LT or maybe intervals.)
            •Once per week, do a few short Strides for basic speed/turnover and focusing on economy/form.

            What do you think? I really want to push on to better aerobic shape in the future (7:30 MAF pace), so I’m willing to reduce/remove the anaerobic stuff to prevent what I fear might be happening now (losing aerobic fitness).

            Apologies if I’m commenting too much on here. Your insights are really useful and have helped me a lot!

          • Jonathan:

            Unless you live close to the tropics, I think that the dips in your speed may be due to cold stress. But the amount of anaerobic work may also be contributing to your drops in speed.

            It’s hard to say why your speed is dipping without getting a closer look at the systems involved (with exercise lab tests). But if it is too much anaerobic work, what might be happening is that you’re just over the line into non-functional overreaching: when you start overreaching, your speeds go dramatically up—your body responds positively to the stress. But when we interpret this as “I’m getting better!” and kick up our training a little bit further, we push our body past a threshold of stress that it can’t handle anymore.

            The training plan you outline sounds really good. However, the best measure of whether your training is right for your body is whether you return “stressed out” from a run (or begin a run “stressed out” the next day). If you do, you’re going too hard.

  • Josh says:

    Hey guys,

    I have very recently have made the switch to MAF training, I’m enjoying it. That said I have a few questions about the MAF testing itself.

    Basics I’m 23 y/o male and I’m using my MAF HR range as 155-160bpm.

    I ran a 10.5km trail route on the 31/12/15, averaged 155bpm, scored 12:15 min/mile.

    I ran a 7.5km relatively flat course on metalled roads 4/01/16, averaged 155bpm, scored 11:05 min/mile.

    I ran the exactly the same 7.5km course on the 06/01/16 (today), averaged 153bpm, scored a 9:58 min/mile (which potentially puts me on for a 5k PR woop!)

    However, in the space of less than a week it looks like I’ve shaved 2 minutes 17 seconds off of my MAF time. I feel that this improvement is a little too good to be true and is probably due to different factors that I’m manipulating that I’m not sure you cover in the above article?

    Firstly terrain, it became immediately obvious in my very first MAF run that running on a relatively muddy trail was making things much harder than they had to be. This contrasted greatly with my 2nd MAF run which was done on metalled roads, I moved much quicker and much more comfortably.

    In my third and most recent MAF run, Halfway through the run I attempted to up my cadence by 10% (~170spm), my HR fell dramatically to 133bpm. I then I obviously increased my speed to attempt to bring my HR back in range. Furthermore, although I was still at conversational effort I found that I could lower my heart rate by breathing maximally. Though manipulating these factors allowed me to put down a good time it left me with more questions.

    TL;DR –

    1. Are MAF tests only properly accurate on tracks, will metalled roads do?
    2. Cadence, is there a cadence you recommend or is this a factor we’re free to manipulate?
    3. Will breathing maximally at conversational effort will drastically affect my results and training?

    • 1. MAF tests can be performed anywhere—the important thing is to run the same route in all your MAF tests, so that your results compare well. (The benefits of doing a MAF test on a track is that any track anywhere will do).

      2. This is a factor you can manipulate: generally, it’s difficult for a lot of people to maintain a high cadence at MAF. But as you get better, you should see your cadence head towards 160 steps per minute.

      3. Breathing maximally is a good strategy (although it doesn’t work for everyone). But the bottom line is that regardless of your breathing rate, if your heart rate is at or under MAF (and doesn’t go above as exercise duration increases), you are doing MAF training. (You can’t stay under MAF with a “bad” breathing rate—one which doesn’t work for you. So, if you are able to stay under MAF, then it’s a breathing rate that works for you, at least at that speed).

  • Larry Waldron says:

    I’ve been on the MAF program since mid-October! It just works!. I’m almost 62. Sure it’s slow in the beginning, but you have to be patient, dedicated and consistent.
    My first 10k was 63 minutes. (I’m normally in the 47-48 minute range in my training runs). Within 3 weeks my 10k was down to 58 minutes. October averaged 58 minutes, November was 54 minutes, December was just under 54 minutes and so far in January I’m under 52 minutes. I ran a 10 mile race on Boxing Day (Canada) and broke my PB from 11 years ago by 1 minute. And I wasn’t really breathing hard. Can’t wait for the upcoming races I’ve got in the next 8 weeks and my 100 miler in May. I’m a disciple and give out your website info to probably 5-10 customers/day.

  • Craig says:

    Ivan
    For the avoidance of doubt – I am very committed to the philosophy and principles of Phil. I credit him with improving the quality of my life and getting me racing again after a 25 year absence.I am now 60 and during the last 3 years I have run 3 Alpine Marathons; Qualified for Boston at the Zurich Marathon in 2015 and generally finish in the top 3 for my age group (55-60 and now 60-65) in all the regional 5 KM Park Runs – I run them at about 20mins and I have run a 6 minute mile (last season).
    However; after 6 years being a fan of Phils approach. I have to say; as a scientist; that I am still confused and uneasy about the MAF formula/model. It seems to me that it is a regression model with a generally close fit age 20- 40 but a high degree of uncertainty beyond age 45.
    Joe Friels zones based on lab (or approx 60-minute TT) tested lactate threshold obviously correlate with science ie a tested value; so has to be logically superior to any regression model including MAF. But a key question remains even if I elect to use Friels model. Should I train only his zone 1 rather than his zone 2 – my calculated MAF would be at the bottom of Friels Zone 1 – I would I would be recovering every day during the base?
    Or let’s ignore Friel and ask the question another way – Assuming you can get an RQ test done – what do you and Phil recommend to be the range around the RQ or calculated Aerobic threshold that you should build your base. Is it best to train 10/15 beats below the RQ; is this where you could retain the personal elements of the MAF model – ie you could start with a lab tested RQ value and subtract the life issues such as stress; illness etc to arrive at a healthier MAF? Mike Pigg was training at 155 with an RQ of .87 47/53 fat carb burn- (ref Training For Endurance Maffetone Phil Maff) if he was sick could you have taken 5 off his lab tested value and if he was injured another 5 etc dropping is healthy MAF to 135-145 – what impact would that have had on his competitive results?
    According to my lab tests my anaerobic threshold is 167; my HR max is 174 and my aerobic threshold is 137. My resting heart is 46 – 50. I currently run my MAF at initially 130 (Friel Zone1); but for my longer runs let it drift to 140 (mid zone2).
    So here’s the deal – suppose I had elected to train below the calculated MAF of 120 and above say 110 ( my walking pace up a sharp hill is 85- 100 BPM and flat 70 -85 BPM ) – what is the likely impact on my running/ competitive fitness of keeping my heart rate zone between 110 -120 rather than present 125 – 140. for all my base training and would this be beneficial? and if this is so; why not train at 90 – 100 and just walk everything? – Hypothetically how long will it take for me to actually run at say 6.5 mins at a heart rate of 110-120- I guess there must be a diminishing returns curve where running is impossible (walkers dont suddenly wake up running at 90 BPM even if they walk 10 hours a day. And that’s my problem with Phils Model .
    I think this is the key grey area with MAF that puzzles a lot of people and has spawned thousands of never ending forums trading opinions BACK AND FORTH with no end in sight,
    Can you clear the mist for me?

    • Craig:

      This is a very interesting and important question. I think that it is in the benefit of every reader that we fully flesh out your concerns.

      It’s the other way around from what I think you are saying: the RQ of .87 would have occurred at a lower heart rate if he was sick. So the changes that the 180-Formula prescribes would ideally (but not always) reflect the new position of an RQ of .87 relative to heart rate.

      Dropping 5 BPM further under the MAF HR would have a very small reductive effect on his training response provided that the anaerobic response (had he not adjusted heart rate) had not led to increasing illness, increasing respiratory stress, an increased anaerobic response to remain at the same speed, and ultimately a forcible reduction in training. (Consider that any anaerobic response would have dramatically increased his RQ at the same heart rate).

      This is the kicker: the protective benefits of training overwhelmingly (but not always) just below the aerobic threshold set the stage for long-term performance advantages that far exceed the performance advantages of training overwhelmingly just above the aerobic threshold given the risks of doing so.

      Which leads me to question 2: if you further reduce your heart rate under the aerobic threshold your base training would be beneficial, but you would see reductions in performance gains commensurate with the reduction in heart rate. The aerobic threshold—which corresponds to the MAF HR—typically occurs at 55-65% of VO2 MAX (which is also where peak fat oxidation occurs).

      Given the genetic VO2 potential of 99% of the population (relative to the energy needs of running), optimizing fuel consumption (fats) at 55-65% of VO2 is more than enough to produce a running gait: either people will increase fat breakdown and utilization to match VO2 at 55-65% of VO2 max or their VO2 MAX will increase such that a VO2 of 55-65% of VO2 MAX is enough to provide the oxygen necessary to oxidize fats at a rate that allows the production of a running gait (but usually both).

      The best way to say it is this: we humans are endurance runners. Fat is the endurance fuel. Successfully optimizing fat oxidation (which occurs at the aerobic threshold) is enough to allow humans to produce and sustain a running gait at endurance distances.

      To answer your question more directly, relative VO2 consumption for 99% of people would be too minute at say 30-35% of VO2 MAX (around 30-35% of HRR) to produce a running gait, even when optimized to their full genetic potential. Likely, the people that could produce a running gait at 30-35% of VO2 MAX are the people who, fully optimized, can run 5 minute miles at their aerobic threshold.

      Does this answer your question?

  • Jonathan says:

    Cheers Ivan. Very useful. Especially what you said at the end about starting next day’s run feeling “stressed” already. That definitely happened to me a few times.

    In hindsight I was probably overdoing it on my aerobic days as well (so not just my anaerobic days). For instance I was often letting it slip and allowing my HR to drift up to MAF to MAF+5bpm (158-163bpm), which was a fine line between feeling good versus fatigued after each run. I could probably get away with that with my current lifestyle/recovery, but I’ve realised I was probably putting myself at unnecessary risk of something going wrong. And perhaps my aerobic development wouldn’t be as good because my body would be relying on the slight anaerobic component rather than primarily fat-burning?

    Anyhow, this week I’ve started fresh and am willing to wipe the slate clean, ignoring my previous paces. I’m now following everything more strictly, meaning I’m running in the MAF-10bpm to MAF range (148-158bpm) as recommended. So on Tuesday I did 50mins/5.8miles @ 8:39/mile with my HR settling at ~153bpm. Yesterday I did 76mins/8.9miles @ 8:37/mile with my HR settling at ~153-154bpm. I felt really good afterwards, invigorated! My RPE was low and my breathing was faint. At the end of it I “felt” like I had worked my aerobic/cardiovascular system, except this time without the undue stress of pushing the pace like before. Interesting feeling. There is a big difference in feeling between 153bpm and 163bpm for me. The former feels like an all-day, infinite energy intensity, whereas the latter feels like a slow burner (albeit it still feels possible to sustain for several hours).

    If I can do 8:37/mile at 5bpm below MAF, I guess my MAF pace is around 8:20/mile? For reference, I did a parkrun/5km in 20:10 a week or so ago, so I guess I’m performing better than my aerobic system suggests still. It’ll be interesting to see how I progress with the “purely” aerobic zone going forwards. I’m feeling positive about it!

    As for what Josh asked about cadence. Personally I have focused on keeping natural form / cadence for a while now. Around 88rpm (176spm) at 8:37/mile yesterday. I think it depends on the person as well the pace though, because if I was going at 9-10 mins/mile my cadence would definitely be lower. Conversely when I run at 6-7 mins/mile, my cadence is around 180, sometimes slightly above. In the past my cadence would have been around 80rpm (160spm) though, so it can be worked on if you “feel” it’s a bit low.

    • Jonathan:

      Yes, I’d say so. It’s important to keep a natural cadence. That said, as you get faster at MAF, focus on increasing your speed by increasing your cadence up to 88rpm before increasing your stride length. The “big difference” that you feel between 153 and 163 means that the 180-Formula is probably calculating your MAF HR (aerobic threshold) right on target.

  • Craig Smith says:

    Very well said – thank you!

  • Grant says:

    Ivan / Phil – I am trying to better understand something about MAF and hoping you would be so kind as to shed some light on the matter to help me clear a few things up.

    What is the scientific definition of anaerobic according to MAF. I have read on this site that when HR exceeds MAF there is a significant shift towards the anaerobic system and sugar being burned.

    Would it be fair to say that the MAF HR formula was correlated over many years of clinical observation / testing to an RQ of 0.85 (50% fat / 50% sugar) and that when MAF HR was exceeded so would this RQ, right up to levels of 1.0 (100% sugar) when working maximally.

    Now if I have understood all of this correctly, my questions start relating to how this applies to keto-adapted athletes. I have just finished reading a lot of Jeff Volek and Steve Phinney’s work in conjunction to reading pieces of the FASTER study.

    As part of this studies testing protocol athletes of both a fat adapted and high carb group conducted a VO2 max test and a 3 hour sub maximal test. The results of the fat adapted group showed that significant fat oxidation was occurring and that the ratio’s of fat to sugar even at higher VO2 %’s was still heavily biased towards fat.

    This is where I started trying to understand how the MAF HR fits in when athletes get to this level. The reason being is that for example, one of the athletes ‘Zach Bitter’ had peak fat oxidation occurring at 74.4% of VO2 max (66.1) at a rate of 1.57 grams / minute.

    – At 75% VO2 max he was burning 98% fat / 2 % sugar
    – At 84% VO2 max he was burning 76% fat / 24% sugar
    – At 96% VO2 max he was burning 23% fat / 77% sugar

    Now this would lead to respiratory quotients well below 0.85 for both 75% and 84% VO2. I am assuming that his HR was increasing as he worked at greater VO2 % max’s, however this is where I might be making an incorrect correlation / assumption; I am assuming that at 75% max his HR is already over his MAF HR. When he runs at 84% VO2 max he must be well above working aerobically? Or is it as long as RQ remains below 0.85 then you can safely say his aerobic system was still primarily being used and he was still training MAF.

    My current MAF HR is 154. I have now been in nutritional ketosis for the last week (actually measuring with blood ketone strips rather than assuming). Now I am going to assume that over time my RQ is going to drastically change and move closer and closer to 0.70 at my aerobic max HR (154). However would I be correct in assuming that I could hypothetically actually start training at say 164 beats per minute if I maintained an RQ below 0.85 as my MAF HR (assuming a lab test to qualify RQ).

    This is why it is so vital in my thinking that I understand the definition according to MAF of anaerobic. As it could very well be possible to have an RQ below 0.85 but be working anaerobically? (e.g. cortisol, lactate accumulation (even possible if still burning primarily fat?) etc.

    I am busy re-reading Phil’s endurance handbook to see if I can obtain what I am after there but can’t see to figure this out properly in my thinking.

    Appreciate your thoughts.

    • Grant:

      The definition of “anaerobic” we use is “the onset of lactate production.” The thing about lactate is that it inhibits lipolysis (the breakdown of fats), which means that the maximum rate of fat-burning (FatMax)co-occurs with the onset of lactate production. After that, lactate metabolism increases, and fat metabolism decreases. So, the “aerobic threshold” (AerT) coincides almost perfectly with FatMAX.

      This is why we talk about maximizing fat-burning and minimizing lactate production nearly interchangeably.

      While I agree that it is certainly possible for the maximum rate of fat-burning to occur well below an RQ of .85, that is a very small percentage of people—the “avatars of the aerobic god,” if you will. These are people with huge percentages of Type I muscle fibers across their entire body, such that their highest rate of fat-burning occurs at a much higher percentage of VO2Max for the rest of us. (FatMax occurring at a VO2 of 66.1 is stupendous).

      As an example of where most of us lie, check out figure 4 in this article. FatMax, which is close to 55% of WorkMax, occurs when ~50% of total substrate utilization is fats. (“FFA” means “Free Fatty Acids”). They’re not looking at VO2 or percentage of VO2Max, but % WorkMax is similar enough a measure to % VO2Max that I don’t mind using it as an informal example. The point is, what you’re seeing is percentages of substrate utilization at FatMax, averaged across subjects. Insofar their subject pool is representative of the overall population, or the population of runners—an open question, to be sure—it’s a safe bet that if you prescribe that the AerT occurs at an RQ of .85-.87, you’ll be hitting close to FatMax for a majority of the population.

      All this said, in order to do better than “mostly” and “majority”, we need to get the right lab tests done with all bells and whistles. An RQ of .87 will probably not be representative of where the AerT/FatMax occurs for a few aerobic monsters. But we believe it to be representative enough of the population that we suggest it as a basic measure for those who are willing to go a bit more accurate than the 180-Formula. The only way to get yet more accurate (as Zach Bitter did) is to cross-reference RQ data with caloric expenditure, and so forth.

  • Markus says:

    Hi Ivan,

    I have been using the Maffetone Method for many years successfully and I trained the last 5 months exclusively at my 132 bpm (except a few bike races) at more than 10 hours per week. It just happened that I had the opportunity to have a full VO2MAX test done on a state-of-the-art $60.000 machine. It also happened that I went into ketogenic diet a few days before the test. My FatMax was 81g/h (1.35g/min) and occured at a HR of 140 bpm at 73% of VO2Max. My RER (RQ) was 0.72 (93% Fat/7% Carbs). My RQ of 0.85 happened at a HR of 157 (90.3% of VO2MAX). My VO2MAX value was 63. I am 54 years old, healthy and trained consistently over the past years. A special scale put my biological age at 39 and the VO2MAX software put my biological age at 36 years. It seem that my HR according to the formula seems a little low. Shall I use 140 bpm or 157 bpm or what else would you suggest? I really appreciate the amazing work and service you provide. Regards Markus, Napier, New Zealand

    • Markus:

      Glad you took this test. The MAF HR intends to coincide with Fat Max. However, the 180-Formula primarily applies to people who hit Fat Max at 40-60% VO2 MAX (which is the vast majority of people). But the 180-Formula tends to underestimate the aerobic threshold for those who hit Fat Max above that range.

      So, 140 (Fat Max) is your MAF HR.

  • Arun says:

    Thanks for sharing this concept.. a couple of questions, 1. How often in a week should one train at MAF HR 2. Should i intersperse MAF HR runs with intervals or should i simply focus on MAF HR for every run??? 3. Can the clocked speeds at MAF HR be dependent on the weather and temperature of the time of the day?

    • 1. It’s very difficult to say: 3-5 times for a beginner, 12-15 for an elite marathoner.
      2. It’s better for 80% of your training to be at or under the MAF HR, and 20% over (80-20 rule).
      3. They can and are, but your heart rate, not your speed, measures the relative exercise intensity your body experiences. So you want to go by heart rate.

  • David Corrie says:

    I’m 37 and have been a runner off and on for years. I’ve run multiple marathons, 50K, 50 Mile etc. Been back training for 8 months after 2 years off. Have run 2, 50K trail races since returning and just completed another 50 Mile trail race. My resting HR in the morning is in low 40’s. I’ve always felt like my HR is too high during training and races. I’m in fair shape now, but my HR is typically in the 170’s and above as an average during a race. I’ve seen it go over 210 during hard efforts on uphill climbs. When I started back to training I basically just jumped into a crowd of runners and tried to keep up with them for months. Finally, I am running with them, but I feel the my HR is way to high. I’m typically 15-20 bpm higher than others in the same age and somewhat fitness.

    My question is: does this indicate a poorly trained aerobic system? Would i be better served trying to reset and begin again with pure HR training?

    ** as a side note, I have been seeing a decline in performance and an increase in HR over the exact same runs over the last couple months, which I feel is beginning to indicate “overtraining”? thoughts?

  • David Corrie says:

    I’m 37 and have been a runner off and on for years. I’ve run multiple marathons, 50K, 50 Mile etc. Been back training for 8 months after 2 years off. Have run 2, 50K trail races since returning and just completed another 50 Mile trail race. My resting HR in the morning is in low 40’s. I’ve always felt like my HR is too high during training and races. I’m in fair shape now, but my HR is typically in the 170’s and above as an average during a race. I’ve seen it go over 210 during hard efforts on uphill climbs. When I started back to training I basically just jumped into a crowd of runners and tried to keep up with them for months. Finally, I am running with them, but I feel the my HR is way to high. I’m typically 15-20 bpm higher than others in the same age and somewhat fitness.

    My questions are:
    1. does this indicate a poorly trained aerobic system? Would i be better served trying to reset and begin again with pure HR training?
    2. when calculating my maximum aerobic heart rate: 180-37= 143. I know at that HR I will be completely conversational. Would this be right? (I’ve always felt like my HR is during training is higher than average and have always desired to run with a low HR like my training partners)

    ** as a side note, I have been seeing a decline in performance and an increase in HR over the exact same runs over the last couple months, which I feel is beginning to indicate “overtraining”? thoughts?

  • Mando etc says:

    Im a sophomore (16) in high doing track and i am going to do this. For me in order to keep my hr at around 160 i need to run at a 9:30 pace, i know this will improve since i will only do aerobic training in the summer but what do i do during track when we do speedwork (interval runs where my hr sometimes goes above 204!)? Should i still do the speed-work anyway? I really want to do this but this contradicts what my coach tells us to do during summer which is do long runs and speed-work. Should i do speed-work here and there or solely stick to aerobic training?

    • Mando:

      The point of doing a lot of aerobic training is to keep you healthy (and specifically, to develop the parts of the body that help keep you healthy). So, as long as you’re healthy, speedwork is just fine. The important thing to remember is to allow yourself to recover from workouts: this means not going into the next hard training session when you’re still overly fatigued from the one before. I’d say that in your off season (summer or winter, or both), do mostly aerobic long runs (at or below the MAF HR), but say, 1 short speed session a week. It’s important that the session challenges you, but it’s also important that you take it easy on aerobic runs for the rest of the week so that you’re completely, absolutely rested (and have been recovered for 3 days) by the time next week’s speed session comes along.

      • Mando etc says:

        if i finished my cross country season with a 20:00 for the 3 mile and continue to do this aerobic plan for the rest of track and summer, is it possible to finish next year’s xc season with a 17:00 or better? what do i have to do in order to achieve this?

        • Mando:

          It is very difficult to know. That is a question best left to a coach who knows your biometrics, as well as your improvement history. That said, it is possible. But I can’t say what you can do to achieve it—your body might respond negatively to the volume of training necessary to achieve it (which is why it’s important to ask this question to a coach that knows your biometrics). But what I recommend to maximize your chances of achieving it is to develop your aerobic base as much as you can during the pre-season, and attempt to recover as fully and completely as possible from your speed workouts.

          • Mando etc says:

            Ok ill talk to him, one last question, does weightlifting and working on the upper body count for the anaerobic exercises that i should avoid? Im saying this because in the summer i try to get my upper body stronger but i don’t know if i should do this since often time the workout i do are anaerobic (like push ups, exercises with dumbbells, bench press etc…). Thanks for the continuous help 🙂

          • Mando:

            It’s really a question of whether you’re healthy or not. Yes, weightlifting is an anaerobic exercise, and you should avoid it during base-building. But if you’re not base-building, it’s a good idea in moderate amounts (again, as long as you’re healthy).

  • Colin McShane says:

    Hi,

    I’ve started doing the MAF method over past couple of days but not sure if I’m doing it correctly. I have to run at just about walking pace to get my heart rate down the between 130 and 140. I’m 40 years of age and have been running for past 4 months or so, all of it very high intensity anaerobic (hill repeats or high tempo runs). I currently run 5km at about 19 mins 30 secs, my heart rate is about 160 at this pace. I’ve been improving pretty steadily but have had a couple bouts of illness so decided to try MAF after some research.

    Should I really have to slow down to just above walking to get my heart rate at between 130 and 140 ? It’s painful 🙂

    Colin

  • Nicko says:

    Lets say i start training aerobically like this to build my base, should i have a rest day? Ive ran for 2 years so im not a novice. What if i incorporate speedwork? Should i have a rest day then? I ran at recommended zone and my pace was around the low nines so its not really that difficult. Just painfully slow :/

    • Nicko:

      Typically, it’s best to take 1 day of complete rest (complete rest could mean a 2 hour stroll in the park—the “stop and smell the roses” kind—for a well-trained athlete). If you incorporate speedwork, the most important thing is to keep speed days staggered with 1-2 aerobic days in between. A sample training week could be:

      Mon – MAF 1h
      Tue – Intervals 30 min
      Wed – MAF 1h
      Thur – MAF 1h
      Fri – Tempo 45 min
      Sat – MAF 2h (long run)
      Sun – Rest

      This kind of training should NOT be considered “Aerobic base-building”

  • Patrick says:

    Hi,
    I may have missed it, but what should the target HR be for races after training for a few months with this method?
    My training HR is 130-140, so looking for guidance on HR targets for 50k trail race as well as 5k, 10k.
    Thanks,
    Patrick

    • Patrick:

      Because MAF trains primarily the aerobic system, and most races have some anaerobic component to them, MAF is not a perfect predictor of racing heart rate. However, we do have guidelines that can help you. We recommend that you test these out to see how they work for you, and add or subtract accordingly:

      For a 50k, you should typically be running at MAF
      For a marathon, 10 BPM above MAF
      For a HM, 15 BPM above MAF
      For a 10k, 20 BPM above MAF
      For a 5k, 25 BPM above MAF

      Specifically, you might find that these values underestimate the heart rate you will be racing at—these suppose that the person is a powerful, aerobically-developed athlete.

  • Heidi Walker says:

    I’m trying to find the correct training HR and I want to make sure I’ve adjusted correctly. I’m 52, I train 6 days a week for Triathlons. My 180 formula puts me at 128 bpm but I’ve added 5 for conditioning and another 5 for training in the high heat and humidity of Houston. I try my best not to go over 140. Is this too high, or will I still increase my aerobic capacity at this level?

    • Heidi:

      I think that adding 5 for conditioning is just fine if you’re healthy. If I were to make any modification to my heart rate based on heat and humidity, I would subtract 5, not increase 5. The reason for this is twofold:

      1) The increase in heart rate due to humidity is caused by an actual increase in metabolic load due to having to engage the body’s thermoregulatory systems. While this heart rate increase doesn’t reflect muscle power output, it does reflect the overall metabolic load of running. In other words, it still reflects exactly how much you’re taxing your aerobic system (and whether your body needs to engage its anaerobic system to supply the rest of the energy necessary to engage the sweating mechanism).

      2) Even in the absence of an increased metabolic load, the body’s stress response itself changes the training stimulus. This is why a 5-hour, leisurely walk in the savannah turns into a life-or-death survival story when just 0.16% of the time (30 seconds) is occupied by fleeing from a tiger. In other words, even supposing that the heat stress didn’t increase the overall metabolic load (which it does), your body is responding to the workout as if it were a high-intensity workout in whatever measure you exceed your actual MAF HR.

      To put all this in perspective, I’m a pretty fast runner (1h25min Half), but I have slight muscle imbalances up and down my right hip and leg. Even though I’m not “injured” or “ill”—my training is very consistent—I subtract 5 BPM from 180-Age as if I were injured. Why? It’s much better for my body if I err on the side of caution than if I try to toe as close to the precipice as possible. Being 5 or 10 BPM below my actual aerobic threshold (which is what MAF intends to measure) will only marginally reduce my aerobic gains, but being 5 or 10 BPM above may produce a different kind of workout.

  • Dan says:

    Hi:

    Thanks you for the information. I’m 53 years old and have been running for 6 years. I found when I race or do intervals my HR can go up to 185 (I just raced a 5K on Sunday and my average HR was over 180). I plan to train by MAF for a year before another race, do I still run at HR=127?

    Thanks

    Dan

    • Dan:

      Yes.

      The most important thing to do is to be conservative with your MAF heart rate. That way, you can be absolutely sure that any workout that you intend to be low-intensity actually produces a low-intensity training stimulus for the body. This isn’t to say that you shouldn’t train at a higher intensity when you think you can afford it or your body needs it, but rather that you make sure that your body is actually getting a low-intensity training stimulus when that’s what you intend.

      • Dan says:

        Thank you for your detailed answer, cleared my mind. Cheers!
        Dan

        • Bill says:

          Should Dan’s MAF be 132 not 127? What determines when you can add +5 to the MAF. Dan’s age and running experience parallels mine and I thought the correct MAF would be 132.

  • amelie says:

    Dear Editor,

    In determining my MA heart rate, I’m not sure which category I fall in. Could you help me?
    I am 26, female, 167cm (5’5” and a half), used to be sedative, but have been exercising 7 hours a week for 11 weeks. In the past two weeks, I did two 10k runs for 58min 35s and 58min 30s each. Those were my best record. I was 119 pounds when I start exercising and now I’m 114 pounds. I have no allergy and did not get any flu or other diseases in the past year.
    HOWEVER, I am pre-diabetic (insulin resistance), with a normal empty-stomach blood sugar but higher post-meal blood sugar level. I’ve been on Metformin for 10 months now. I’ve been between 110 and 122 pounds since the age of 18. And I don’t feel diabetic in daily life.
    SHOULD I SUBTRACT 10 OR 5 OR NOTHING, IN THE FORMULA?
    Thank you very much!

    Amelie

    • Amelie:

      Thanks for your comment. Since pre-diabetes is one of the issues that contribute to poor aerobic function, I’d say that you’d be much better off subtracting 10, as the formula says.

      On a related note, I’d caution against thinking about race times, particularly in the shorter races, to think about your aerobic function. The body’s stress response has been known to produce epic race performances, even over long distances. If we focus on race times, we may overlook the state of the body after the race. Preserving the body is the key to performance consistency, and performance consistency is the key to long-term performance increase.

      Hope this helps!

  • Donna says:

    This is very interesting information for me. I’ve been training for 5 years now for triathlons and marathons. I am a female and 55 years old. I trained very hard last year from Oct 2014-Aug 2015 for Mont Tremblant IronMan (August 2015), which consisted of 90 degree weather and high humidity. I raced 2 full marathons and a Half Ironman in the same time period.
    I never trained during my runs with a heart rate lower than 135 and that was a tough number to achieve for me. It seemed my heart rate at a slow jog would be in the mid 140’s. During races the heart rate would average 165 and top out some times at 175 (mostly at the the end of the race).
    I have gained 15 pounds and 7% fat in the last year and I watch my nutrition and don’t smoke or drink alcohol. I am also tired. I have been checked out by the doctors for several things and I do have hypothyroidism and am on medication since December which is working and I have a 48 resting heart rate.
    According to your 180, my max should be 125-130. I ran this morning for 3.5 miles and stopped a lot to lower my heart rate. It wanted to climb into the mid 140’s.
    With all this background, do you think it’s related to me running anaerobically the past few years and I should run at this 125-130 heart rate? Was I running too high?
    Thank you for attention to this matter.

    Donna

    • Donna:

      Yes, certainly. Your experience is like that of a lot of other people.

      The problem is the volume in which you were training over your MAF. As long as you have signs and symptoms of hypothyroid, it’s not a good idea to run above your MAF HR very much at all. But once you’re healthy, it’s fine to add a bit of anaerobic training every now and then.

  • cameron says:

    Hello,

    I am a fairly new to running having run approximately two years off and on. I ran my first half marathon last May in 2:32 which for me was a major accomplishment. Soon afterwards due to lack of motivation and summer I quit running but picked it back up again this past January. I registered for the same half marathon I ran the previous year and despite torrential rain and 40+ mph headwinds finished in 2:21. I ran a downhill half (net drop 3000ft) last weekend in 2:09. Like a lot of other people I would like get faster. I would like to be able to run a sub 2 hour half and eventually be able to average around 1:50. Most of my training is done at lower heart rate but I haven’t seen much of an improvement. I am a 35 year old male, approximately 127lbs and 5’5. When running at 135-145 bpm I’m lucky to be pacing lower than 11:15 min/miles. I’m running around 25-30 mpw usually the same course so I can watch for improvements.

    For me what is most frustrating is having friends of the same age who don’t run regularly and are able to finish a half in 1:30 on 15 miles a week whereas I am out busting my butt 5 days a week and can’t even break 2 hours. What exactly is the secret? Is it more MAF? If I continued for another year would I expect to see some major progress?

    Thanks
    C

    • Cameron:

      Some of those friends may have a very high VO2 Max baseline and a very high VO2 Max genetic ceiling, not to mention that they may also have excellent running mechanics.

      There are many, many secrets. It is very likely that if you look into those friends’ childhoods, you’ll find that they walked everywhere, or played outdoors all day, or biked around town with their friends, inadvertently developing massive aerobic bases when they were kids. If they moved a lot as children, they are likely to be much more coordinated in very subtle ways, which make a huge impact over the course of 25,000 steps (the average over a half-marathon).

  • Jennifer says:

    Hello…This is fascinating! I just started looking into this method and have a question. I’ve been running all my runs in a fasted state (in the morning before eating breakfast) with the intent of teaching my body to burn fat. I became interested in this method to gain speed. That being said, will the fasted state AND the heart rate method result in a “double whammy” fat loss situation? Secondly, I drink 6 cups of coffee before every run. Will this artificially increase my heart rate? It didn’t seem to when I tried your method out this morning. According to the 180 formula I should be running under 130 (45 yrs old with allergies). My avg pace to keep it at around 129 was 9:50. Your thoughts are appreciated!

    • Jennifer:

      Yes, absolutely. In fact, running in a fasted state but with an anaerobic heart rate can cause much greater stresses than running with an anaerobic heart rate alone. In a fasted state, the body is relatively bereft of sugar and muscle glycogen. If you require the body to use more sugar (by going anaerobic), it’ll have to replenish it at a much quicker rate than in a non-fasted state. Now check this out: the hormone that increases the supply of blood sugar is cortisol (the stress hormone). So if you go anaerobic in a fasted state, you’ll kick up your cortisol levels to a much higher level than otherwise, plus they’ll take much longer to come down.

      What I said only applies to anaerobic work. Staying aerobic while in a fasted state is just fine.

  • Jennifer says:

    Hi, again…

    So how would this spike in cortisol levels manifest itself? By triggering fat-storage/hoarding mode, essentially sabotaging the whole purpose of the fast?

    Is there any added benefit to running aerobically AND fasted?

    Thank you!
    Jennifer

    • Jennifer:

      First and foremost it would be stress, essentially stopping the body from recovering from the workout (and subsequent workouts) and endangering its health. If this becomes chronic, then yes, it will result in long-term fat gain.

      Yes. The benefit is that by forcing the body to use almost only fats, you put the body in a position where all of its aerobic development is going to happen due to improvements in fat-burning (typically, aerobic improvements are only mostly due to improvements in fat-burning, since you are also burning some sugar even under the MAF HR). Running fasted (meaning in a ketogenic state) while under the MAF HR is a great way to turn yourself into an ultradistance athlete.

  • Raj D says:

    Hi Ivan,
    I just did my first MAF test this morning and I was startled, by the results which had a full minute of cardiac drift between each mile. I live in a hot and humid climate which might contribute but I try to get out early enough to beat the sun. I haven’t come across this much drift anywhere else. Do you have any thoughts or concerns?
    Many thanks,
    Raj

    • Not particularly. Just keep running at your MAF HR. For a very in-depth discussion of heart rate, I highly recommend this link.

      • Raj D says:

        Hi Ivan, just wanted to give a quick follow up 2 months later… This morning’s MAF test is 1:20 quicker than the first and cardiac drift is down to 15 seconds between miles. I’m sure most of that can be attributed to weather but the rest is MAF and I’m grateful for it. Many thanks again.

  • Tyler says:

    Hi Ivan,

    I hope you are still addressing comments to your article.

    I am 46 years old and have been an avid runner for the last 20 years. I started using a heart rate monitor almost exactly four months ago. I normally run between 40 to 60 minutes (5km to 8km) a workout about every other day. There has also been several occasions where I have increased by distance to 16km to 21 km (I recently ran the Stuttgart, Germany and Davos, Switzerland Alpine half-marathons).

    My reason for commenting on your site is that I have not noticed any decrease in my pace time. I am very conscious of staying in my aerobic zone during my workouts and will walk if needed. Even during the above mentioned half-marathons I treated them as training runs and stayed in my aerobic zone as much as possible.

    On a positive note I have not sustained any injuries, my vital signs have improved greatly (108/66; 55 resting HR), recoveries are faster, and I have lost about 10 lbs. Overall I feel great so I’m not getting discouraged just a bit vexed.

    My question is why hasn’t my pace time dropped? I’m thinking that I am not putting in enough overall mileage and run times during the week.

    Thanks for any insight or recommendations you can provide.

    • Tyler:

      Thanks for your comment. When people’s aerobic system starts getting healthier, it isn’t always the case that the first biomarker of health to improve is speed. The fact that your vitals are improving is an improvement in the very same system (the aerobic system) that will give you greater speed down the line. Think of it as the body having more work to do in certain areas before those very real gains you are making—as evidenced by your improved vitals—transform into speed gains.

      If you feel comfortable, and don’t feel that increasing your mileage will increase your overall stress levels, adding a few more miles is prudent. But given that you are improving, I don’t think it’s altogether absolutely necessary.

  • Jason L. says:

    I have recently found and totally love the ideas behind the MAF technique. I am 49 yo male, with a 180 Formula of 136. My resting heart rate is in the low 40s, (and has been even when I’ve been out of shape in the past). I’ve slowly started reducing the amount of carbs I get in my diet, with most of them now coming from fruits and vegetables. I’ve been training exclusively at the MAF rate for about three weeks. In the first three weeks, my pace has already decreased from around 11:00 min/mile to around 9:50/mile. I’ll also note that I live in Florida, and most runs have heat indexes in the 90s right now, so I assume those times will improve as weather cools down.

    I actually did a treadmill VO2Max test with New Leaf six years ago (the one with the mask for gas analysis). That test said I had a “Aerobic Base” heart rate of 145, which the test describe as “the maximum heart rate at which you burned fat as the dominant fuel during your assesment.” I assume this is the same number that the 180 Formula is trying to come up with (and it’s fairly close to what it would have been six years ago!). There’s also a section with “Comparison To Others” which says that my VO2Max is 58.2 ml/kg/min and is “largely genetically predetermined and has little to do with the efficiency of your metabolism.”

    It also showed my Anerobic Threshold heart rate of 155, describing it as “your highest sustainable exercise intensity” and “when exercising at this high intensity you might notice that you cannot talk or breath easily. This is an intensity that pushes you beyond your AT, causing your body to burn mostly carbs.”

    I took that test about six months after I started running, and while I was training to run my first marathon. I was about 30 pounds heavier than I am now. Fast forward to today, and I am now a regular runner, and frequently run in races (they keep me motivated!). My times have improved over the past few years — pretty closely correlated with the weekly mileage I’m doing.

    So here’s my questions:

    1) My fastest 5k is at 6:39/mile pace (avg heart rate of 156), my fastest half marathon 7:21/mile (avg heart rate 163). Given that my MAF runs are average around 10:00/mile, that means I have an enormous amount of room for improvement, correct?

    2) Assuming I do have a huge amount of room for improvement, should I continue to run exclusively at MAF heart rate? My primary interest is endurance, not speed (well, except for #3…)

    3) I am running marathons in October and January in an attempt to qualify for Boston. Should I be training exclusively at MAF before those races? I do have a couple of 5Ks and a 15k coming up, are those anything to be concerned about?

    And lastly, thank you for all you do and make freely available. This site is an AMAZING resource, and the information fantastic.

    • Jason:

      Thanks for your comment. Let me answer in order:

      1) Yes, that’s what I would expect.

      2) Exclusively or nearly exclusively. Unless I’m aerobically base building, I always throw in some strength training, skill work, speed work, etc. You don’t even have to go near any sort of fatigue to produce massive gains from these sorts of workouts.

      3) Not if you’re healthy. Since you have those races, you can treat them as the bulk of your speed workouts. I would do a few fast 3 and 5 mile workouts every couple of weeks or so, but I’d stick with about 95% MAF training at least.

  • Lauren says:

    Hi Ivan!

    Thank you for all of your insights. They have been incredibly helpful over the past several months!

    I am 32 years old, and my max aerobic heart rate is 143. I suffered a stress fracture 2 years ago, and because of complications, I am still working through muscle imbalance issues as I return to running. Physical therapists have instructed that I must correct the imbalances with simple strength exercises like squats and planks.

    I need to build my aerobic base, evidenced by a super slow MAF test pace. Given the existence of muscle imbalances, do you still recommend skipping the strength training until I have a solid aerobic base? Or, can I incorporate really easy squats and crunches while building the base?

    Thank you!!

    • Lauren:

      Certainly not. Do the strength training, and train aerobically by walking or using an elliptical machine—zero impact—and start “building an aerobic base” in the strict sense only after your physiotherapists give you the green light. I recommend also that you take up jumping rope (once your muscle imbalances have been corrected) to bridge walking/elliptical and running.

  • Steve Troxel says:

    In the table for 5K predicted pace versus your MAF test pace, which mile MAF pace should you use – first, last average? Thanks!

      • Steve Troxel says:

        Thanks Ivan! I am sold on this training. I’m 57. I qualified and then ran Boston in 2015 at 3:30:00 using conventional training – tempo runs, etc. I ran a marathon in December at 3:24:30, again using conventional training. I will be running Chicago in 4 weeks. This time around I have been using MAF and love it. It takes all the pressure off of running. I run as fast as my HR allows – I set my max at 125. My test this week had a first mile of 7:55 and a last mile of 8:15 so I should be in good shape for a PR. My goal is 3:23 – 7:45 pace. I have done almost no speed work except for a little downhill runs to work on leg turnover. The only thing I think you guys should stress a little more is that this still takes miles (time) to see an improvement. I regularly run 70 miles a week and I tell people that they should not expect to see improvement if they only go out a few times a week for 30 minutes at a time. I know you don’t like firm “rules” but an hour a day, five days a week is probably minimum. Thanks for all you do!

  • Damian says:

    Am sold on the philosophy in theory. I am a 46 year old open water swimmer though take part in the occasional aquathlon so need to maintain the running. I recently decided to step it up (and would like to do a half marathon again) so have been running 3 times a week with a steady pace of 6min per km and interval training and longer sunday runs at 30seconds either side of race pace. However my breathing and HR is always stressed at these pace’s so want to try the MAF training to regularize these.
    What I have encountered though is that running at the 133HR recommended this requires a pace of 8.30 per km. As a result my run is closer to a shuffle and is leading to stress on my ankles and forefeet which I do not have with my previous longer pace. Would appreciate any feedback on this. Should I be running at a more comfortable pace but slowing down to a walk to keep to the 133 HR as opposed to a very slow continuous jog?
    Any help and feedback much appreciated

    • Damian:

      One thing you can do is shorten your stride to quicken it. If you can walk at a brisk pace while staying reasonably close to 133, that’s a good idea too. You can train jumping rope to keep some of the bounce in your legs, if you decide to walk for your MAF training. Jumping rope trains a majority of the muscles that you use while running, which means that once you become more powerful at your MAF HR, it will be quite easy to transition into running.

  • Cam says:

    I am very interesting in MAF and have been training at this level for a little over a month. My only question is how is one able to run races at paces they never train at? My MAF heart rate is 145 and depending on conditions such as weather and where I am training whether it be on the treadmill during the summer or trails I can run roughly 10:30 – 11:30 min miles. However, during a race I am not going to want to run that slow especially for half and full marathons. Therefore how can I accustom my body to handle faster paces for these distances?

  • Mark says:

    I have been training for the last two months with MAF. Because of the summer heat almost all of my runs have been inside on the treadmill. I have also taken my MAF tests on the treadmill but find that it has not been very accurate. I am running with a Garmin Forerunner 230 that has an built-in accelerometer and has an indoor running mode option. However, it seems that the pace is directly related to arm swing and anything that interferes with that such as adjusting clothing, hydrating or wiping sweat off my face has a direct effect on the pace reading. Therefore in my opinion it has been wildly inaccurate for providing accurate data for a MAF test. With the coming of fall and winter I will be taking my runs outdoors and doing the same with my MAF tests.

    However, my concern is with the colder weather coming, how can I best measure increase in aerobic fitness if the weather will be affecting my pace and overall MAF results? In other words how do I know if gains seen in a MAF test are directly related to changes in weather or aerobic fitness?

    • Mark:

      Take your MAF tests on a treadmill in room temperature. That way, even though you’ll run slower outside when it’s cold, you’ll always be able to compare MAF tests with one another in an environment that isn’t taxing physiologically. In any case, aerobic fitness doesn’t just wax and wane in a vacuum: declines in aerobic fitness are always preceded by stressors and paired with signs and symptoms of ill health (fatigue, difficulty sleeping, stress, inflammation, etc.). So when these signs and symptoms are absent, and you feel well even though your speed is dropping, you can be quite sure that it’s because of the weather. Finally, you can track your seasonal speed decline and improvement and compare it to that of the following year.

  • Mark says:

    Ivan,

    My apologies not explaining myself a bit better. I was trying to explain that during cooler weather I am able to run a lot faster than during warmer months. Do you still think it be better for me to perform MAF tests on a treadmill when like I mentioned I have not been able to get accurate readings?

    Thanks for the suggestions.
    Mark

  • Geoff says:

    Any recommendations for how best to handle anaerobic “life activities” during the base period ? For instance if moving house, heavy loads will be lifted, or we may need to clear brush, shovel deep snow, or chop and stack wood bringing heart rates above MAF. I’d suppose the best answer would be to wear a heart rate monitor during such activities and keep heart rate below MAF, but if that is not feasible under the circumstances what is the next best mitigation tactic (besides a proper warm up and cool down)? Should those non-optional anaerobic activities simply be viewed as background physical stresses of life and accounted for appropriately when evaluating MAF test results? Is it best simply to accept that those activities may have a negative impact on total base training or are there other specific activities which can help blunt their impact on the development of an aerobic base?

    • Geoff:

      Great question. I don’t have a lot to say, because your intuitions are right on target. They are best looked at as background physical stresses.

      Also, consider this: A bird’s eye view of the aerobic base won’t really conclude that it is for endurance (although of course, that’s one of its responsibilities). What the aerobic base is for is to absorb stresses. Endurance in particular is a huge stress: it is essentially the prolongation of athletic stress, which is why one of the most salient features of a powerful aerobic base is that it is able to prolong athletic activity while keeping the body healthy.

      So, it’s unlikely that those stresses are having a negative impact on aerobic base training. Don’t get me wrong—they are having an impact on your aerobic speed. Namely, to reduce it, or rather, delay its improvement. But the reason that speed improvements are slow or delayed isn’t really because the aerobic base isn’t being developed, but rather because it’s using its newfound strength to healthily absorb all of those background stresses. When all that’s said and done, it doesn’t have strength left to show speed improvements yet.

      This doesn’t mean, of course, that you shouldn’t try to mitigate background stresses when possible. One of my favorite ways to help remove background stresses is to help the body psychologically “break away” from work (physical and otherwise) and reset before exercising. What I do personally is to actively set the intention of training smoothly and stress-free while I’m putting on my training gear. Even though physical labor does tire the body and have a real impact that can’t be gotten around, a “reset” after the work is done or before training aerobically will help you to bring as little psychological stress or baggage from the prior activity, reducing your stress levels commensurately.

      Hope this helps.

  • Alan says:

    I tried to slow down but my heart still stays up there. At 39yo my MHR should be around 181. I went out and trotted a 14:00/mi pace. My HR stayed around 150-160. I had to struggle to go so slow I was walking. Furthermore, I had to compromise my running mechanics, which made for a painful ending after 3.1 miles. If I want to stay in aerobic range, I can’t run, I have to moderately walk.

  • Greg says:

    Hi Ivan, I have a half-ironman coming up and was wondering if there would be a target pace i.e. 30 seconds faster than MAF? Thanks for your guidance!

  • Adrian says:

    Hi there, I’m a reasonably fit 30 year old triathlete (70.3 PB in the 4:30 range) and have been incorporating the MAF approach for some time now (exclusively for the past two months or so and off and on for approximately a year). What I’m finding are that my MAF HR feels very different on the bike vs run. On the run my MAF pace is approx a 4:20-4:25km (I’m Canadian and we use kms… sorry) which is a very manageable pace that I can sustain for my long runs without significant amounts of fatigue the next day.

    On the bike however, sustaining 155 BPM is nearly a threshold effort (currently my MAF power is ~90% of my Anaerobic Threshold power) and results in a significant amount of fatigue the next day. I’m wondering if you can explain this as a MAF HR for me is equivalent to a strong tempo effort, whereas I find reading these threads a MAF HR almost seems too easy for many. Is this because my muscular endurance is the limiter vs my aerobic fitness? Is a discrepancy between bike and run MAF HR typical? Should I reduce my MAF HR on the bike to align with the RPE I feel on the run? I feel that training at 80% MAF on the bike would leave me way too fatigued to have any success in the 20% anaerobic efforts. I know this is a lot to throw out there any help would be greatly appreciated as I’ve been curious about this for some time.

    Thank you!

    • Adrian:

      Yes. The MAF HR isn’t necessarily the heart rate at which you want to do all of your low-intensity training sessions. We define the MAF HR as the heart rate at which the aerobic system develops most quickly without increasing stress levels. But as an athlete gets aerobically fitter, it becomes less necessary to train the aerobic system in the fastest way possible, and instead it makes more sense to train at a lower heart rate to open up more training volume to anaerobic efforts.

      On the bike, the neuromuscular demand is higher because the body’s metabolic effort goes into much fewer muscles than in running. (The body use a much more diverse set of muscles in running because of the increased stability demand: you only have one point of support.) That said, on the bike the metabolic demand is the same as in running.

      So you’re using your aerobic system in the same way—it’s just more tiring for your leg muscles because the body is pouring much more of its metabolism into them than with running. It’s a good idea to reduce your cycling intensity to reduce muscle soreness, but this should cease to be a problem as your leg muscles get stronger.

  • Rachel says:

    I’m an older female runner, age 57. Been running, albeit slowly, (5k 35 min, 10k 1:11, half best time 2:36) for four years and would like to improve my pace. Just had a physical and I’m in great health. The 220-age goes out the window for me, as I’ve had my maximum heart rate at 200 in races with no fainting or throwing up. I’m thinking about doing the MAF at a 140-150 bpm range, what do you think? I tried to keep it under 137 today and I did mostly walking at a 16 minute mile pace! I think I’ll be able to run very slow at 140-150. For the past 4 years, on most of my runs, my average heart rate has been >150-160.

    • Rachel:

      The MAF HR points to a physiological threshold of the body, called the aerobic threshold (the anaerobic threshold usually occurs 30-40 BPM higher). Above this threshold begins anaerobic function, which is where stresses on the body begin to accumulate significantly. Unless you have laboratory evidence that your aerobic threshold occurs higher than the 180-formula suggests, I do not recommend making that change.

      In every case we’ve studied, the higher a people’s true physiological aerobic threshold occurs above the value that the 180-Formula predicts, the faster they are at an aerobic heart rate. Put another way, the people for who you would recalculate the MAF HR to a higher heart rate are already incredibly fast.

  • Cary Blackburn says:

    Hi I’ve just started the MAF method of training (3 weeks in to it) and have just started reading the Big Book. I am a 60 year old cyclist who has been training for about 4 years based on the traditional cycling zone system and have improved and have had no injuries. My MAF then is 180-60+5 = 125. My max HR is 184 (found from experience) and my lactate threshold heart rate (Anaerobic threshold) is 166/169 (found from field testing and a VO2 max test). From this information the Aerobic Threshold which I have been working to has been 138 (top of Zone2) calculated from the VO2max test which correlates with Joe Friels LTHR-30.
    The question I have is MAF the same thing as this Aerobic Threshold and if so given the disparity of the numbers which one should I be working with? I should add that an endurance ride where I spend the majority of my time (2/3hrs )at 138 or slightly below is a hard ride and I know I’ve been extending myself whereas the same ride keeping between 115-125 (MAF) is very easy and very slow.
    I’m asking this as I don’t want to potentially waste 3 months only to find I should actually have cycling a little harder. Thanks

  • Steve says:

    Is the MAF method appropriate for a 60 year old who runs recreationally but not competitively? My resting HR is 55 and my max about 172. I am not a fast runner, and my runs currently only amount to about 4 miles or so. My HR quite quickly goes to 145 – 150 or more, and when it hits 160 I usually stop and walk. I find I loose capacity quickly if i stop for a while, but also can pick up distance reasonably quickly when I start training again, The problem is that I always feel rotten when I’m done a run, feeling like I’ve overdone it, sometimes for the rest of the day. I think this may be because I very quickly go into the anerobic range and stay there, and this is hard on me. I would like to try the MAF method, but I am wondering if it would help a man of my age and condition. 180 -60 would have me working out at a HR of 120. This would be a very slow jog which I would probably have to frequently reduce to a walk. I will never be a racer, but my ambition is to be able to go for a 30 minute run at a heart rate that leaves me feeling good rather than feeling faint. Is the MAF method applicable to older people like me? Or should I give up on this goal? I’ve been running off and on for several years, have always had this issue with running at a high HR and feeling it afterwards, but it is becoming less tolerable as I get older. Your advice would be appreciated.

    • Steve:

      Yes, the MAF Method is certainly applicable. In fact, training the bulk of your miles at an aerobic heart rate is one of the key ways to improve longevity and quality of life (which includes movement). What you’ll see happen is that your aerobic power will increase with time, most likely to the point that you’ll be able to produce a brisk, easy running cadence, quite a bit faster than you are now. The MAF HR is the maximum HR at which your body remains unstressed (in addition to the fat-burning benefits you may have read about). Training the body to run at this HR will help you run and move faster and better in a state that your body is quite comfortable with—ensuring that you don’t “overdo it.”

  • Dan says:

    Interesting thread.
    I’m 55 with no illnesses and a fairly low stress life and have been doing a ketogenic diet for a year. I also dropped my 1/2 marathon time by 10 minutes between 2015 and 2016 (2:00 to 1:50), so I’ve been using a max heart rate range for my aerobic maximum–if it’s between 125-129 I hold steady. I started base building about 4 months ago. I’m wondering about mileage– for the past couple months I’ve been trying to do some 12 mile runs; I start out at a 12:30 pace, but by near the end of the run I basically have to be at a very slow jog/walk to keep my heart rate below aerobic maximum. Is this normal? I’d like to do a 1/2 marathon in a month, will I have endurance for the whole race? Should I be adding strength training and more intense runs? Closely related, I’d like to do a full marathon later this spring–any tips for upping mileage?
    (Sorry for so many questions). One more–reading through this thread I’ve seen the 80:20 rule mentioned. When does one start using this–is it during base building?
    And a comment. I live at 6500 ft. and my MAF tests have not improved much which is somewhat annoying. However, right when I started this and then about 3 months later I visited relatives in Michigan (600 ft elevation) and my MAF pace improved from 12 min/mile to 10:30.

  • Chris says:

    Hi

    Another newbie! Yes, I too have recently stumbled across this website after reading a few books from rich roll, Scott Jurek and kilian jornet which has given me some great tips and inspiration. Am sure it’s extremely common for people who have not trained in this way ever, do find it difficult to begin with. I started last week and find that my heart rate increases too high into the 170s (180 – 41) so I really have to focus to get it down, which is a trot around a 2.5 mile route with a little undulation.

    What I didn’t realize was the fact of keeping an eye on, not just on your heart rate but also other factors such as muscle imbalances, stiffness, etc which all contributes to stress upon the nervous system, which is what am struggling with at the moment. And, I too am worried about this approach as I have races booked this year, the main events are 2,marathons, first one in July over the highest peak in the Lake District, then 2 skyrunning events in September, following finally by a trail marathon in October for my birthday, plus shorter distances in between races yet to be booked.

    Me being typically me, wants to charge into my training building myself up, but consequently end up stiff and sore regularly, even though I take lovely hot baths, stretch out, foam roll, work on my core etc (if am honest I’m probably not getting myself into a decent enough routine). Tonight I ran 14:30 min/m over a 6.5 mile route, again slightly undulated, and ended up with a heart rate at 150-155 majority of the time. What did I notice in my body to contribute to stressors? Stiffness in my hips, quads and calves. No wonder my heart rate was so high!

    Whilst beginning is tough, I take it I should stick to shorter distances and build over the weeks? I want to be fitter than I was last year in the Skyrace in which I bonked but completed, I bonked because I descended far too quickly even though I was having the time of my life loving it, before the half way point!!

    Am I too stick with the lower heart rate in all activity? I.e. Cycling and swimming?

    Really good site, will get the docs book soon ???

  • Dan says:

    Hi,
    My apologies if this has been answered in previous threads. I’d like to try something different in my training/racing program, and am interested in focusing on the Aerobic Base building phase over the coming months. That being said, I’m registered for 3 races over the next few months. Will the whole purpose of the Aerobic Base period be lost if I carry on with doing these races, or can I manage both? I can obviously just continue on as I have for the next few months, and then begin an Aerobic Base period after the committed races are behind me.
    Thanks!

    • Dan:

      It won’t be lost. The 3 races will slow down your aerobic progress, but the period of aerobic base training in between races will help maximize your rest and recovery. In fact, what I suggest you do is decrease your regular high-intensity training (but don’t eliminate it entirely), so that you have at least some anaerobic training every week. That way you can still be prepared for your races, while also ensuring that you are resting and recovering as quickly and completely as possible.

  • Brad says:

    I have been training using the MAF method for 4 months now and pace times have been slowly increasing. I am 38 years old any my heart rate is 142. When I use this training method on longer runs, typically when I hit about mile 12 or 14, the pace I have to run at to keep my HR at 142 decreases. This is typically on a 18-20 mile run. Is it normal to have a faster pace for the first 12-14 miles, then slow down for the last 6 or so miles? For example, for the first 12 miles my pace was around 9:25/mile and then after about 12 miles it slowed down to over 10:00/mile or even slower. Then the next day I ran 6 miles and my pace was 9:15 at a heart rate of 142.

  • Brad says:

    I am a year 38 year old who has been using this training method for 4 months. My training rate zone is 142. My long runs are generally 16-20 miles. For the first 10-12 miles my pace at 142 HR is approximately 9:30/mile and then toward the last 25% of the run or so, the pace slows down by a minute or two. Is this normal? If so, could you explain why? Thanks.

  • LOMA L MOSER says:

    ………….[a. If you have, or are recovering from, a major illness (heart disease, high blood pressure, any operation or hospital stay, etc.) or you are taking medication, subtract an additional 10.]……………

    This additional 10 beats is definitely me, as I broke my neck in 6 places (hit by a car on my bike) January 2, 2017. I had zero opportunity for exercise for 3 months (after the first 8 weeks I underwent spinal surgery to remove a sheered-in-half disc and to plate my C4-5 together, so recovery started over again!).

    After 12 weeks my neurosurgeon approved me for “cardio” exercise on a machine (bought a bowflex max trainer for the least amount of impact involved), and daily walking 1-3 miles. My husband and I walked the local causeway 2x weekly also (3-5 mi each time) to add a little incline-resistance.

    After 16 weeks I was approved to start “running” on soft surfaces (grass, sand, composite track) and only in 1/4 mi, walk-run intervals not to exceed 1 mile total per day. That went well and now, at 19 weeks, I am building to 1 continuous, easy mile. (This week I ran 1 mi at 11:06; 10:46; 11:21….”My trained” mile in the past is around 9:00. I run 2 half marathons a year for the past 5 years or so and was well trained prior to my accident, but in trail biking at the time.)

    I also started on a strict Keto, removal of artificial sweeteners, much of my previous dairy, WOE in January after my accident. (After I was able to eat solid food again.) Now I’m learning to be a strong KetoAthlete! I love how god I feel. I have only lost about 6 pounds in 16 weeks, but IDK–maybe its because I’m healing??

    ANYWAY…I’d like to know HOW LONG I should keep subtracting the extra 10 beats from my 132 (180-48=132), post surgery?? I am now 2 1/2 months since my surgery…Have not been sick or had a cold, and continue to improve in my neurosurgeon appointments…and I have been walking for at least 3 months now…

    • Loma:

      The best way to know you no longer need to subtract 10 BPM is if that you can genuinely say that the reason that you subtracted 10 BPM in the first place no longer applies: if you are “fully healed” from your surgery (in the most generous sense of the term), then sure, add them back.

  • Erin says:

    Hi Ivan,

    I have a question. I trained earlier this spring for a half marathon with MAF and thought it was great but one thing I never could find an answer on that I would like before I start training for my fall marathon. It is unclear to me with MAF as to whether you are supposed to run at a comfortable pace until you reach MAF and then move to a walk OR are you supposed to run at a slower pace, which may look more like a quick shuffle, until you reach MAF. Or does it really matter as long as you adhere to moving to a walk and lowering your HR once you exceed MAF.

    Thanks.

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