The Running Trifecta

By February 17, 2016 December 9th, 2016 Athletic Performance, Endurance Sports, Exercise

Getting and staying healthy is the real key to reaching your training and racing goals — and getting faster.

Most competitive runners have at least three goals that include better training, more racing and getting faster. This “trifecta” may be seem like the holy grail, but those who train their body to use more fat as fuel can reach these as well as another important goal — improved health.

Conversely, training harder and farther won’t usually produce the desired results without risk of overtraining, and resulting ill health and injury.

Staying healthy is actually a more effective strategy to achieve running goals than pushing the training envelope. The benefits include no injuries or fatigue, less chance of illness, and more consistent training. What’s more, there’s no catch. It’s legal. You don’t have have to move to a high mountain, quit your job or even spend more money.

All this can be achieved simply by increasing the amount of energy to the muscles. Sounds simple enough. Here’s how it works.

Whether sleeping, working or running a marathon, the human metabolism relies on ATP for energy. The muscles obtain this fuel from two sources:

  • Fat stored in adipose tissue (known as body fat) and small amounts of fat (triglycerides) in muscles.
  • Sugar in the form of glucose, which is stored as glycogen, with blood sugar also available, along with lactate which is converted to glucose.

Fat is the most important source of endurance energy and an important part of our metabolism. Even the leanest runner, for example, has enough stored fat to run hundreds of miles at an easy pace. When racing, such as a 5K or 10K, and particularly longer distances such as a marathon, runners, with the right metabolism, can burn significant amounts of fat for energy, conserving sugar for a final kick.

By burning more body fat, all runners will attain better endurance, are generally faster, remain lean and are overall healthier with less injuries and illness.

Sugar is very important too. Even when glycogen stores are full; however, it is quite limited (to a couple of minutes of running). Sugar is used in particular for very short quick paces such as when you’re trying to catch the runner ahead as the finish line approaches. Using up glycogen stores too quickly, like going out too fast in a race, reduces energy, decreases overall running pace and is a recipe for bonking.

The precise mix of fuels varies from one runner to the next, and is based on types of food eaten, especially the previous meal or snack, as well as training pace and stress levels. Here is an overview:

  • Food. Food has an immediate and powerful effect on the mix of fuels. The more carbohydrate consumed, especially refined products (the kind most people eat), the less fat and more sugar we burn for energy. This is especially a problem when consuming carbs before a workout or race, and even the previous evening’s meal. Even moderate amounts of carbohydrates can reduce fat-burning in many runners. One can even consume too many natural carbohydrates, such as fruit.
  • Training Pace. Fat-burning occurs in the slow-twitch, aerobic muscle fibers. Developing these muscles during lower rather than higher intensity running helps build better endurance and fat-burning, and can contribute to better race times. Once aerobic function is developed, which could take three to six months, one can add intervals or other higher-intensity training. Not surprisingly, many runners perform their best while maintaining a strictly aerobic-base training program. An option is to add more racing to your calendar for more high-intensity efforts.
  • Stress. The accumulation of physical, biochemical and mental-emotional stress, if excessive, can impair fat-burning and force the body to use more sugar.

There are various indications the body may not be burning enough fat and relying too much on sugar. These include:

  • Frequent hunger. Burning more fat for energy conserves sugar throughout the day and night, not just when running. Frequent hunger usually means inadequate energy, with associated complaints that include fatigue, poor sleep, and strong cravings for sugar and carbohydrates.
  • Increased body fat. When the metabolism burns less fat for energy, more of it is stored. Waist size is a good indicator of body fat content, better than scale weight.
  • Performance plateau. Many runners progress well in the early stages of training and racing only to reach a premature plateau without attaining their human potential. This is often related to a deficiency in the aerobic system. The primary component of a great race is to fully develop the body’s ability to use fat as fuel.
  • Increased disease risk. Diabetes, pre-diabetes, high blood pressure, increased blood fats, and other health dilemmas are often indications of poor fat-burning and excess carbohydrate consumption.
  • Calorie confusion is also common. Many runners mistakenly believe burning more calories with more and faster miles will help slim them down. This obviously is not true as many frustrated high-mileage athletes can’t shed the extra body fat. Here’s an important question that helps solve the confusion: Which calories are you burning during training? Burning more sugar calories by running longer and faster won’t necessarily burn off excess body fat.What to do:
  • Eliminate refined carbohydrates, and reduce natural ones, to best match your needs (use hunger, training energy and other indicators as a guide). Reducing carbohydrates means adding more natural fats to the diet. Coconut oil, avocados, butter, nuts and seeds and others can actually help burn more body fat.
  • Use a heart-rate monitor to keep your training intensity lower in order to improve fat-burning. By doing so over time you will develop the ability to actually run faster at the lower heart rate, which translates into racing faster.
  • Reduce any stress factors that can be easily identified and corrected.

Both healthy eating and building the aerobic system can help burn more body fat to provide the muscles with more energy to train better, race more and get faster. An important bonus follows, one of better health, which will in turn further improve fitness.


  • Jennifer says:

    I see people posting my MAF is such a pace. I don’t have one maf pace during a run. Ill start out at one pace but as I go further into my run I have to slow down more to keep MAF. This is normal???

  • Bas says:

    I’m a competitive masters rower and amateur cyclist, tring to find a balance in training and daily life. Trying not to overtrain but also not train too easy. Made both mistakes in the past but competitive performance is well enough and has been slowly improving over the last few years albeit with some regression along the way. Some of this regression was training related, some of it family related. 🙂

    Finding the MAF HR leaves me really confused. At 34 years old it should be 180 – 34 – 5 = 142 beats per minute. Right now when cycling this is about 240 watts steady (at 75 kg). This definitely doesn’t feel easy and i will get overtrained by doing this every day for 90 minutes. When rowing it is about 180 watts (2:05/500m) on the ergometer during the last 5 minutes of a 45 min session, well cooled.

    However on this page i read a few times that MAF HR should be at FATMAX heart rate. I have also read an RQ (RER?) of 0.87 as where MAF should be. So i dug into the results of a VO2max test i had to do a few years ago (i was 31 years old at the time so calculating MAF the same way would have given me 145).

    Looking into the results of the test, in which i had no warmup and a “Ramp 200 2 watts/6 sec” protocol was used, i could see the following results:

    MAX: 412 watts, 5136 L/min, RER 1.19, HR 185
    MLSS: 318 watts, 4329 L/min, RER 0.90, HR 171
    RER0.87: 282 watts, 3857 L/min, RER 0.87, HR 162
    HR145: 235 watts, 3387 L/min, RER 0.81, HR 145
    RER0.70: 172 watts, 2440 L/min, RER 0.70, HR 115

    Under 172 watts i see a RER of around 0.7, even going as low as 0.6 at around 110 watts. What’s going on here?? Maybe i was glycogen depleted (i was trying a low carb diet at the time) during the test? I remember that i lacked high end power and my max heart rate was only 185 while i had seen 191 when i was 27 and 189 less than a year ago. I also think i could never do 318 watts for an hour at that time.

    I am really confused by the fatmax thing as this would suggest that my MAF HR is only going to be 115-125. While i think my MAF could be lower than my peers this seems really low. However when i train easy i rarely let my HR go over 130 and the next day i’m almost always ready for more. I tend to train polarized right now, alternating cycling and (indoor/outdoor) rowing, sometimes throwing anaerobic training in the mix which can be a race or 10x 1 min on/off session.

    Can you help me out to find my MAF HR? Is it supposed to be at the pace/watts you can do every day/recovering or should it be faster?

    PS my resting HR is 38 well recovered, if it’s of any use.



    • Bas:

      The MAF HR is the heart rate at which FAT MAX occurs. Physiologically speaking, FAT MAX is the best indicator of when “low-intensity training” changes to “medium-intensity training.” So, for the purpose of exercise prescription, there is no better measure than FAT MAX.

      The reason we’ve talked about RER in the past (outside of the context of FAT MAX) is because we were keeping up with the latest science on low-intensity training—which was all about RER. Fat max became a useful and well-described concept very, very recently, and that’s why we’ve begun discussing it more frequently than RER.

  • Kylie Ross says:

    I am 45 yr old woman who has well controlled medicated asthma and I normally train 3 – 4 days a week – 1 x 5km , 1x 6km and now a “long” 10 + km – – building up to a half marathon. How do I best incorporate the MAF into my program? I have previously had mild plantar fasciitis and struggled to keep my weight manageable for my exercise. During my long run last week (11km) my foot was sore (usually happens at about 9km) and is still tender today (4 days later).
    I would like to know if I should continue the distances I have covered or would you recommend that I stop my program all togetherand follow the 15min warm up 10-15min MAF and 15 min cool down for a period of time?


    • Kylie:

      I would reduce the distance slightly, in order to never run with any kind of pain or discomfort. The issue is that more discomfort means more stress. Not only does this reduce aerobic function, but it also causes the body to view running as an adverse experience. The more that happens, the less the body will want to grow in that direction. So, temporarily reducing your mileage might be the best way to let it naturally increase in the long term.

  • James says:

    Hi Ivan,
    Any reason you can think of as to why I run a lot faster outside than I can on a treadmill (at MAF HR or a zone of 15bpm below). On a treadmill if I say walk for 5-10 mins then increase the speed to a jog/run there is always a much bigger rise than there is if I run on the roads/trails outdoors and it taks more of an adjustment to come down if I do go over MAF. Do you think it could be I’m more mentally relaxed outdoors or that the treadmill ‘uncovers’ some sort of imbalance that outdoor ‘norma’ running doesn’t ? I’m at least 1 min 30 per mile faster outdoors than on a treadmill at the same HR.

    • James:

      Think about what the treadmill does that the road doesn’t: it makes the road pass under you at a fixed speed, kind of like a downhill that you have to keep taking, which you’ll fall if you don’t.

      Now, there’s fundamentally 2 ways of approaching a downhill: you either let yourself go, letting gravity take you, or you hold back and brake yourself, staying in control. I think that our subconscious approach to the treadmill can be really similar. You either let the treadmill take your feet and swing them behind you, or you subconsciously brake to stay more controlled. I think you might be doing the latter.

      Of course, while the treadmill is still going at only one speed, braking creates a much higher demand from your leg muscles, so that speed you choose will be slower.

      That’s my best guess.

  • Matt says:


    Because I am running so slow I feel like I’m losing fitness.

    Do you think eventually doing more MAF runs will benefit me in the future so I will be faster in the future than I was in the past?

    • Matt:

      Yes. Think about the body as if it were a building. If you want to add floors (strength), you had better updated the foundation first. Sure, you’re not adding floors in the meantime, or some are falling into disrepair, but that’s only happening because you’re diligently developing the foundation.

  • salvatore says:

    Hello, I hope you mind this quick question by using the comment format. I am 67 a trainer and triathlete for 31yrs.I have followed the dr for many years now. Do you think I could also add 5+10 to my 113 mahr since I am over 65 and have been training and racing this long? Are you still in favor of adding the 10 if you are over 65 and being fit condition? I really would like to know what your answer is.Not just for me but for others who are in the same fitness level.Thank you so much.

  • Matt says:


    I did the last few runs all by Heart Rate. I did the MAF test but I was using 142 HR. My times were 8:46, 9:04 and 9:12.

    Should I restart and go back down to 137?

    Thanks so much for all your help.

    • You’re welcome.

      Yes, I’d say so. It’s best to “keep your fast runs fast and your slow runs slow.” Being conservative by 5 BPM to be absolutely sure that your aerobic runs are indeed aerobic is only a good thing.

  • Matt says:

    Thanks so much for your help Ivan!
    So to make sure I understand you correctly go MAF for a week then the next week do 2 MAF runs, one long run, one interval workout where I do maybe a few more reps and see how I feel and adjust accordingly?

    Also, I’m 43 so would my MAF be 137 or 142?

    Thanks again!

  • greg says:

    At what pace (HR ) should one race if one has been training for six months at MAF. I presently train at 112bpm (180-68). But soon will be entering Sprint Triathlons ( 1/2 mile mile swim, 16-20 mile bike, and 5K runs. My last event before MAF training took about two hours. I never checked my heart rate consistently but I believe at the time I was in the 140 range. When I run stairs an try to get to a max heart rate it usually tops out between 155 and 160.

    How would one use a race to one’s aerobic base? What target HR?

    • Matt says:

      I have no questions about my health and really want to avoid injury and overtraining.

      So lets say I run four times a week and I did two easy runs, one long run, and one hill or interval run along with 2 strength training sessions.

      And every month reduce the volume for a week.

      Would this seem like a good plan? Or maybe just go by how I feel? So if one week I feel tired slow down, take more days off?

      Thanks for your input!


      • Matt:

        That sounds like a pretty decent plan, and quite prudent, particularly as a first stab at designing your training. What I recommend is taking it back to the drawing board after say, a month, and make necessary adjustments. What I’d experiment with, for example, is playing with the intensity: Increase the amount of anaerobic training (very modestly) for a week so that you get better at perceiving when training becomes stressful, and aren’t kept wondering whether you could be training more or could be training faster, and you get used to perceiving (rather than idly wondering) whether your present training is a good fit for your body: not too much but not too little either. Another modification could be to run at MAF for a full week instead of decreasing volume—a week of full MAF (with 2 rest days at the end) will probably do more for your recovery than a lower-volume week of hybrid high/low intensity training, and you’ll get an aerobic boost as well. And a MAF week will also help your strength training.

        And absolutely slow down and take it easy if you feel tired. You get the biggest training adaptations when you’re well-rested and able to engage fully. Erring just on the conservative side in terms of rest is only a good thing.

        To everyone else: this is NOT a discussion of aerobic base building, and not a general guideline. It’s specifically an answer to Matt’s question.

  • Matt says:

    I’m 43 and running about 35 miles a week or so and lifting roughly 2 times a week about 25-30 min. each session.

    I’ve been running for about 7-8 years doing one long run, one hill or speed workout and one or two easy runs a week.

    My diet is good with lots of veggies, healthy fats, a bit of animal protein. I’m already pretty lean so weight isn’t an issue.

    I feel pretty good. I do get fatigued sometimes after workouts but for the most part I feel good.
    What would you suggest I do. Do I need to go to a full 3 month base building using 180-43=137?

    Or can I do a couple easy aerobic runs a week and throw in a interval workout each week? Also can I still keep lifting?


    • Matt:

      Unless you are trying to do some explicit aerobic base building, or have concerns about your health, it’s not really necessary to go full-on 100% MAF. Personally, I suggest that everyone do 3 months of base-building over the winter, because the body (in particular the heart) does need that prolonged rest.

      What I typically like to do is polarize my training a little bit more.

      Usually what I do is stick by the 80-20 rule for my regular season, structured around polarized training microcycles. For two weeks, I’ll train “endurance,” meaning 95% at MAF and 5% above (for me, usually a mile of 100m intervals or something comparable each of those weeks), and for two weeks, I’ll train “power,” meaning 65% at MAF and 35% above (a combination of strength, tempo, intervals, hills, etc). That way, I get a powerful training stimulus for two weeks, and then the next two weeks I get the chance to make sure I’m completely absolutely recovered and rested, before embarking on another two weeks of higher-percentage HIT.

  • Dejan Radovanović says:

    I started to run by your advice for two weeks now and it seems already works great for me. Could you please explain how will I know how long my base training period should last (three or six months) and when my aerobic function is developed so I can add intervals or other higher-intensity training. Thanks

    • Dejan:

      The best thing to do is keep track of your aerobic development with monthly MAF tests. Once you’ve been improving for 3-6 months (3 if you feel confident that’s enough and you’re healthy) it’s reasonable to add 10-20% of anaerobic training into your routine.

  • Jon says:

    When I started heart rate training with MAF of 138 in early December, I could run at about 10 minutes a mile. Now in the end of February I am almost at 11 minutes a mile at the same intensity. As of January 1st, I eliminated all refined sugar from my diet and if I ever eat bread it is sprouted whole grain. Why do you suppose that I am slowing?

    • Jon:

      It’s hard to say without more info. Has the weather been getting colder? How are your stress levels and health?

      • Jon says:

        The weather has been all over the map. I seem to have been cold adapted though. Stress levels are moderate. I think that the MAF estimated heart rate may be too low for me. Using Friel’s method my MAF of 138 would put me in a constant recovery zone. Zone 2, where he recommends training to burn fat would start at 142 and end at 148 based upon my lactate threshold test. My lactate threshold is 167 and my max HR is 195. I am 38 years old.

        • Jon says:

          My health has been good also. My diet has been all organic with grass fed meats and free range local eggs with plenty of coconut oil and nuts and seeds. Lots of salads and no added sugar in anything.

        • Jon:

          Perhaps. The 180-Formula isn’t as good as an array of lab tests. I’d recommend getting a Fat Max test done (where you burn the most fats). That’s the place you want to be. What I can tell you is that generally speaking, someone who is well fat-adapted (whose MAF HR is at a higher heart rate) tends to be still very fast at a lower heart rate. But whatever that Fat Max test says, that’s your MAF HR.

          • Jon says:

            I understand that test can give me a more accurate MAF HR. It goes without saying that someone who is faster at a higher heart rate is faster all around. My question really is this: Do you believe it is possible to regress in fitness due to running at too low of a HR?

          • Yep, provided that this person is ONLY running at a low heart rate. To be clear, we only advise people to run only at or below MAF if they are aerobic-base building, ill, injured, overtrained, or recovering. (The reason being the very concern you bring up).

            To add a little more to this, let me say that the reason we talk so much about running slow is that there are a lot of people whose fitness is often held together by spit and bubblegum. I mean this almost literally: a preponderance of athletes out there are holding their bodies together with athletic tape, or racing only by the leave of their compression gear. These are examples of fitness built on a very deteriorated health foundation. It’s not that these people are at risk for overtraining or injury—they’re on the threshold of overtraining and injury.

            Now think about what happens when they decide to focus on developing that health foundation: it’ll take a long time to get the health up to the point where it can support that much fitness. And what are you doing? You’re taking hours off preserving fitness (which is bound to collapse in a few months or a year, anyway) to develop health. As you focus on developing health (by strengthening the aerobic base, in this case), the body will cut back on “fitness” that it only built because of the necessity to respond to training stresses it was already buckling under. So yes, you’ll lose fitness, and all along, this was the right call to make. The reward for doing so? Your future fitness will be that much more robust (and in all likelihood, that much greater) than your present fitness.

          • Jon says:

            Thank you for your last response. I don’t know why I couldn’t reply to it. That sums it up nicely. I feel as though maybe I misjudged what my MAF should be. I have been training consistently for a few years, but I tend to get a cold once in the spring and once in the fall. I subtracted instead of added and maybe I shouldn’t have.

          • Glad to hear I was helpful. Let me know how everything goes.

  • Dhiren says:

    Thanks for all the great information Dr. It has been very enlightening and has forced me to rethink the type of training I was doing.
    I am 38 yo male and carrying a little bit of extra weight. My problem is that even a very slow jog takes my HR to above the MAF threshold of 142. Should I adopt a run walk strategy? Or pick up another activity such as spinning or elliptical which can help stay under the threshold; until my aerobic capacity builds up.
    There are many pages dedicated to learn to run fast by running slow and other concepts. But cant find any resource to address my problem; which I realise is common to amateur and beginners.

  • Mike says:

    Been trying aerobic training for last 2 months or so, was very difficult at start but my time per mile is down about 3 min’s per mile – I still find it hard to believe but running slower is speeding me up – just want to say thanks for site and info.

  • Ilsa S says:

    Thanks for all the great information on this site!

    I’ve recently started using MAF method to help me work towards running longer and faster with ease. I have a training question. I am a 48-year old woman with no medical issues. Even on level terrain (the track), my slowest jog raises my heart rate above my MAF HR (should be 133, it is 143). A walk on level terrain will not get my heart rate high enough. Should I run at the slow jog in the threshold HR (143) thinking it will come down with greater fitness or keep running/walking to yo-yo back and forth between too low/too high to a happy average? Or change my training to another activity (like spinning) where I can maintain the MAF HR more easily? What about road work with uphills and downhills where your HR fluctuates more dramatically? Just keep switching between walk and jog?

    Thanks for your feedback!

  • Jeff S. says:

    I am so glad I read about Dr. Maffetone in “Natural Born Heroes” and found this site. As an former college football player I was once in great shape, but find myself gaining weight over the years with no real understanding of how to lose it.

    It finally all makes sense now after discovering this site and reading blog posts like this one. My wife and I are excited to adopt these principles in our cycling training. I always trained in the anaerobic range and was frustrated with the slow progress and failure to reduce body fat.

    Thanks for sharing this life-changing information!

  • sergio says:

    excelente la nota, muy buen ejemplo para continuar el entrenamiento

  • César says:

    Hola Phil e Ivan, excelente artículo!!!
    Quería comentarles que tuve un día de entrenamiento intenso en la montaña después de haber hecho el TWT y llevar unos 15 días más incorporando otros alimentos uno a uno, mi duda era ¿qué como en este día distinto?, teniendo en cuenta que iba a pasar mi frecuencia e iba a empezar a quemar glucosa.
    Y descubrí tu batido en tu página y fue ¡excelente! me sentó muy bien en el estomago y rendí mejor de lo que esperaba teniendo en cuenta que llevaba casi un mes consumiendo muy poco carbo y azúcar.
    Muchas gracias desde Argentina.

  • Pascale says:

    Thank’s ! I really enjoy your advice. Ride my bicycle ( at the end of a 70 k tour in wich 15 ‘ at 50 K/h speed on a flat rood, am the only one who could ride 20 k more. I am 61). I give your advice to my kines too, since they are runners. One of them intends marathons, trails for 2 days…and does not feed propaly…, get’s flu, injuries at his ankles…but does not want to listen to what I say…I a m a senior and he is 34…So, eventually, life will teach him. So, thanks again !

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