The MAF Heart Rate White Paper

By March 25, 2016Research


  • Cary Blackburn says:

    I have an accurate lactate threshold/functional threshold heart rate of 169 with a maximum heart rate of 184 obtained through cycling testing. Joe Friel indicates that my Aerobic Threshold is therefore 30 beats below this at 139 which is considerably higher than your 180 – age (60). Which figure would you recommend I use.

  • Andrzej says:

    Hi author and all readers!
    Super article! I’m using Phil method since a little more than a month and I have to tell that it works on me!
    I’ve read all articles on your website and just wondering if I could some of them translate for Polish? There are many runners, cyclists and swimmers here in Poland that would be happy if they could use Phil method but the problem may be the language knowledge.

  • matjaz says:

    To editor
    Reading your articles and comparing them with Joe Friel book Fast after 50, I’m confused a lot. You advised to do most of training in lower heart rate zones while Friels philosopy is to do most of sessions at higher heart rates to keep my body as fit as possible.
    I’m 55 and I’m in endurance sports ( triathlon, cross country skiing, mountaneriing) for more than 30 years. I’m using heart rate monitor for two decades already. And now which philosopy to adopt?

    • Matjaz:

      I’d say to adopt ours. (I’d recommend that you read through our sources for a more in-depth discussion of each of our points.) Low-intensity training actually keeps the body far healthier, and health is the foundation for fitness. While high-intensity training is important, it’s also actually not the mainstay of either health or fitness. That is why every elite athlete incorporates a preponderance of low-intensity training. The greater the percentage of high-intensity training they do, the less likely they are to be elite.

  • Sebastian says:

    Hi Ivan,

    Could you please confirm that the data in Table 1 are correct. For example the %Fat and %Sugar at HR 146.

    Thank you.

  • Cliff Randall says:

    I cannot seem to download the PDF for the Heart Rate white paper.

    Please help.

  • Alex:

    We’re seeing what the problem is.

  • Teri Smith says:

    I’m 50 years old and have been running for 4 years. I recently started using a heart rate monitor, and the 180-age formula. What I have found is that I run extremely slowly – 9minutes/kilometre (don’t know what that is per mile). If I go faster – up to 7 minutes per kilometre – then my heart rate goes up to 155/160. I am about 10 kilograms overweight (working on that), I’ve lost weight following LCHF, but am I doing something wrong?

  • Camm says:

    I submitted a question on the “Method” page and it just disappeared randomly so I will try again.

    I am new (2 weeks) to the MAF method that I found in one of Mark Sisson’s books. I changed my diet away from all refined carbs (only veggies and fruit) with healthy fats and animal protein about 1 month ago. I was, up until about 2 weeks ago, training nearly all the time in the cardio “black hole” well above my MAF HR max. Many weeks that would mean 6-8+ hours of chronic cardio and strength training. I started noticing earlier this year that it seemed to take considerably more perceived effort to cover the same distance (trekking, biking and paddling). And in the last month or so it seem that my resting HR is a bit higher. I have also lost about 7% of my body weight in the past month as well.

    I the last 2 weeks I have trained almost exclusively under my MAF HR (130 BPM). This is incredibly slow – mostly a fast walk and bike efforts have to be done on the trainer to avoid any moderate or above hills. What kind of progress should I see? My MAF times over a rolling to hilly course are 14+ min / mile due to all the walking and having to run so very slow. Are those times something to be concerned about beyond the terribly slow pace? I have a scheduled 18 hour adventure race in 12 weeks — so I am very concerned about my progress and/or the indications that a lack of progress points to some other health issue.

    My typical week now is 6-8 hours of MAF training run/walking and spinning on the trainer.

    Thank you for your response in advance.

    • Camm:

      Thanks for your comment. I vet every comments individually and it usually takes me a couple of days to get to them, due to a variety of other duties.

      When someone has a very low speed at their MAF HR, it’s usually because they have an aerobic system that is impaired or undeveloped (or has deteriorated due to overuse). In particular, the increase in perceived effort is due to the fact that the workload has begun to decrease your athletic ability than increase it.

      Typically, people start seeing progress after the first month of MAF training, and they can see up to 10-15 seconds per mile increase per month. The aerobic system (which is what MAF Training targets) is a system that takes a relatively long time to develop. In reality, the robustness of the aerobic system can keep increasing for decades. So, in a very real way, that’s the timeframe that you’re working with. The most important thing you can do to keep making progress is to allow your body to recover fully from workouts, and to always err on the side of recovery. Excess training stress breaks down the very infrastructure that allows us to develop the fitness to perform at a high level. It is this infrastructure which takes a long time to develop (but can also continue developing for a very long time).

      • Camm says:

        Thank you. It looks like I need to get used to slow running / fast walking for a while.

        Three (3) quick questions as a follow up:
        1) When is it appropriate to add In strength training — starting easier with pull-ups, push-ups and core stability? That will often bring my HR briefly well above the MAF max for me of 130.
        2) Occasionally my current MAF runs will have one or two very brief periods where my HR alarm goes off and my HR slightly drifts for a moment or two over 130. Does that cause a set back in the primary work of re-pair/developing the aerobic engine?
        3) Is it likely that my training volume of 6-8 hours is too much or having deminishing returns for the effort? I am training for long events lasting 12 to 24 hours, but I don’t want to do more harm than good either. Positive progress is more important than putting in a lot of fruitless hours run/walking and easy spinning on the trainer.
        Thank you again for this resource.

        • Camm:

          1) As long as you’re not ill, injured, or overtrained, or explicitly trying to improve your aerobic base.

          2) That’s OK. It doesn’t matter as long as it doesn’t become rampant.

          3) Yes, you’re probably seeing diminishing returns. That said, it can’t really be helped for extremely long events. What I’d recommend is that you put in a lot of hours walking.

  • Russell Dawson says:

    Is there a genetic component to success with the MAF philosophy?

    In other words, if I (1) always train just below MAF heart rate, (2) focus on eating healty-fats with a high fat, low carb diet, (3) get proper sleep, (4) do my best to eliminate life-stress, etc. along with everything else Phil suggests, is it possible that I will still not see much increase in training speed at MAF heart rate because of some lack of genetic ability?

    I’m mainly curious if professional athletes like Mark Allen and Mike Pigg, and even successful recreational athletes like Floris Gierman have seen success with MAF training simply because they have a genetic propensity for success with MAF?

    • Russell:

      Great question.

      There is a genetic component to endurance performance capability. In other words, the names you describe become elite performers in the endurance sphere because of their favorable genetics.

      However, there is no genetic makeup such that endurance performance capability would be better arrived at by running at a high heart rate and burning sugar, if that’s what you mean. There is not or has never been a single person on the planet for whom the system responsible for their health and endurance performance is the sugar-burning system. (I don’t mean to go on the offensive here—I think a lot of people may have this question sitting in the back of their minds.)

      People who have more powerful sugar-burning systems (a.k.a. people who are genetically tuned for sprinting, weightlifting, and to a lesser degree cutting sports like soccer and rugby) still rely on their aerobic system, and specifically its ability to burn fats for recovery and the sustenance of health. It will never produce the energy necessary for elite-level endurance performance, but that does not mean that their more powerful sugar-burning system can become responsible for their health and their (more modest) endurance and recovery capabilities.

      So, to come back to your specific question, most people aren’t slow at the MAF HR because they don’t have the proper genes. They’ll never become incredibly fast at the MAF HR, but I’d say that the overwhelming majority (99%+) of people have the “genetic ceiling” necessary to run 7:30 minute miles at MAF (in their 30s and 40s). Whoever is running 13+ minute MAF miles isn’t because of their genes. This is far from the immense engine it takes to run 5:40 MAF miles like Mark Allen (or the 5:10 or so that I think Alberto Salazar says Galen Rupp can run), but it’s also more than a lot of people think they can manage.

      Of course, to really hit your genetic ceiling, you might need to be living the life of the monastic athlete for quite some time, and be fully immersed in your athletic development. It might not be something that most of us have the opportunity to do given our commitments, responsibilities, and lifestyle, but that’s, of course, a different question.

      Hope this helps.

  • Anthony Marsh says:

    I would like your advice/opinion on my MAF training heart rate. I do not expect that you can give me a difinitive answer based on the limited information I am about to give you that’s why I am just looking for an opinion.
    I am a 54 year old male. I make my living as a Fitness and Sports instructor teaching at a military base. I pride myself on my fitness and healthy lifestyle, I like to think that I have a pretty high level of fitness. I am a runner, mainly half marathons, and I am a soccer player too. I still play in a competitive league against guys 30 years younger than me and they generally have a hard time keeping up with me…lol.
    So I will get to my question. My max aerobic heart rate is 126. For the last few weeks I have been performing all of my runs at 126 plus 5. I read in your MAF method paper that sometimes for people older than 65 they may need to add 10 to their aerobic heart rate max.
    I realize I am a few years away from that age, however given my high level of fitness for my age do you think it would benefit me too add 10 beats now or should I stick with the 5?

    • Anthony:

      What I recommend is that you stick to the 5. It’s very important that your aerobic runs remain fully aerobic, so that you’re able to develop your aerobic system optimally and restore yourself well. This in turn allows you to run your anaerobic runs with abandon.

      So it’s not quite a matter of whether you’re fit enough, but whether it’s better to be conservative with the measure or not. And with aerobic runs, it’s better to go conservative.

  • Iacob Gheorghita says:

    Definition of anaerobic metabolism is prone to confusion. It is defined as energy production (ATP) without the need of O2. But not any glycolysis means lack of O2. Which way we are measuring the “anaerobic metabolism” by measuring the lactate which is produced from pyruvate but lactic acid is produced even when on rest.
    Up to the aerobic threshold (fifty-fifty glucose/fat), the blood lactate is about 0,5-1,5 mmol/L. Where did it came from, since we are talking about pure aerobic metabolism?
    Obviously, it is a rhetoric question because there is a continuous turnover of pyruvate to lactate and back all the time and this “anaerobic metabolism” does not mean a lack of O2 uptake.
    If so, what happens above the aerobic threshold? Which is the significance of the increase in serum lactate up to 4 mmol/L? It is a proof of anaerobic metabolism due to lack of O2 or it is about the increase about three times of the glucose metabolism and consequently the increase in pyruvate production?
    It is possible that anaerobic metabolism due to insufficient O2 uptake starts only when we encounter the lactate threshold?

    • Iacob:

      We’re not saying that all glycolysis means a lack of 02. We’re saying that “Using sugar for energy allows the body to increase its energy production and work rate far beyond what the rate of oxygen uptake allows.” This means that because sugar is more easily burned, continually increasing glycolysis will eventually get you to exceed the rate of oxygen uptake. Only when that happens do you get anaerobic function.

      But the point, more specifically, is that this isn’t the case for burning fats: you can only burn them aerobically. So the more you rely on sugar metabolism, the more you are at risk for (1) your energy production to move beyond your supply of oxygen, and (2) your oxygen uptake to become unmoored from your rate of energy utilization. Both result in anaerobic function.

      Lactate may be produced at rest, but it is produced due to a relative disparity between the supply of oxygen and the energy utilization of the body. Like you say, there’s not a lack of 02 uptake, but what there can be is a net oxygen insufficiency due to the increase in glucose metabolism: glycolysis that occurs in the presence of oxygen produces pyruvate, and that which doesn’t produces lactate.

      We’re not talking about “pure” aerobic metabolism. As you say, there is no such thing. If you look at how we define “aerobic” and “anaerobic” in the second page, we are talking about the overall gestalt function of the body, not whether every single cell is effectively being supplied oxygen to fulfill all of its energy needs. So 02 uptake only matters insofar the rate of uptake matches or exceeds the body’s real-time fuel utilization (in which case the body as a whole is functioning “aerobically”) or is outpaced by it (in which case the body is functioning “anaerobically”).

      While, as you say, there is turnover from pyruvate from lactate and back all the time, it does not increase from rest up to the aerobic threshold. Beyond the aerobic threshold, it increases, to put it lightly, dramatically. So the important thing to focus on is the gestalt function, rather than the absolute function. The significance of 4mmol is questionable: people have theorized that it describes the maximal lactate steady state (lactate threshold), beyond which the body cannot buffer lactate. However, blood lactate at the lactate threshold has been shown to vary between individuals.

      The biggest indicator of the presence of some anaerobic metabolism is lactate, because that is its main by-product. (The biggest indicator of an increase in anaerobic metabolism is an increase in lactate, for the same reason). The point is that you will not see increases in lactate beyond resting levels up until the aerobic threshold (AerT), because there has been no increase in anaerobic metabolism.

      But what matters ultimately for the body is not the particular reason for which anaerobic metabolism begins (whether it’s increase in glucose utilization or insufficient 02 uptake) but the fact that it’s there (or more specifically, the fact that it’s begun to increase).

  • Iacob Gheorghita says:

    Thank you very much for your detailed answer.
    I agree, there is all the time a delay between the increase in energy expenditure and the “diffusion” of O2 toward the mitochondrial “generator” (oxidative phosphorylation). Also, the more glucose is used, the more lactate is circulating in the blood. The lactate per se isn’t an issue but its significance it is important.
    Many “sport consumers” heard about HR zones. There are a lot of stories, theories and rules. It took me some while to understand that there are two measurable and significant thresholds: the aerobic threshold (180 rule or the 0.85 RQ HR for those who are measuring VO2) and the lactate threshold.
    As a matter of fact, I am one of the Phil Maffetone’s admirer. I’ve read his endurance training and racing bible almost two years ago. It is very likely that he saved my life but not only.
    Yet, I still have many questions. I also have feelings that there are more stories still untold: pathological ventricular hypertrophy, ischemic heart disease, both induced by excessive physical effort, consequences of hypertension in prolonged high HR physical efforts, excessive salt loss and salt compensation.
    I have to confess that I am honored to participate to this discussion.
    Thank you.

    • Iacob:

      It’s a pleasure to answer your questions. You are a constant commenter here on the site so I recognized your name from the initial comment. Don’t hesitate to comment if you have any more thoughts on this topic or others.

  • Miki says:

    I’m 67 years old, and have been running since I was 20. Usually I run about 40-50 miles per week. I’m completely healty, and don’t suffer from any injuries or major/minor illness, but 3 years ago I started taking a Statin pill a day to treat a mildly high cholestrol level (my cholestrol levels since taking the pill – total, LDL, and HDL – are perfect). Does this still put me in category A, and I have to deduct 10 from my result? I also fit into category D, so what should my max heart rate be?

    • Miki:

      Yes, absolutely. Just subtract the 10 BPM from category A.

      • Miki:

        You can’t be in both category (a) and category (d) at the same time. In other words, if you haven’t had any of the problems in category (a) for more than 2 years, you can’t be in the process of recovering from them. Effectively, until you’re completely recovered, you still have whatever issue placed you in category (a).

        As far as the additions to be made over the age of 65, these are made on a case by case basis regarding the health of the person. As with the previous example, someone can’t be unhealthy enough to be in category (a) and be healthy enough to warrant adding 10 BPM.

        Ultimately, you pick only one category—the one that best fits your situation—and select your MAF HR from it. Only if that category happens to be category (d), and you’re older than 65 years of age, you can consider adding 10 BPM to your MAF HR. In other words, you only make one more operation beyond 180-age unless you’re over 65, in which case you make a second only if you fit into category (d).

        Hope this helps.

  • Geoffrey Levens says:

    I realize, as you just posted above, one can only be in one category at a time. But I am wondering if additional reduction of top of training range could be indicated in my case which I think is unusual.

    I am 66 and have been doing moderate, alactic training (with kettlebells) only for past year plus. I have hypothyroid and take med for that so 180-66-10=104. I recently started to use an ergometer/rowing machine (air resistance) every other day, and my perceived effort needed for getting into and staying in training HR range seems to me to be quite high. To even get to bottom of my training range (94) requires the full 15 minute warm up at a Borg scale level of 15-16 and I need to maintain level of intensity that for at least another 15 minutes to stay in bottom 1/2 of training range. At that point (total 30 minutes at Borg 15-16) my HR will very gradually begin to climb into upper 1/2 of training range which is about where I would prefer to train at. I can not back off at all until about 45 minutes at that level effort or HR will immediately start to drop. Finally after about 45 minutes total at that Borg level of effort, I need to take brief periods backed off to about a Borg 13-14 to prevent going over HR of 104 but still mostly need to continue at about a Borg 15.

    I have been timing my training for 30 minutes (+ the 15 minute “warm up” + another 10-15 minute cool down period) for several weeks and have just bumped it up to 35 minutes/work out.

    So is this level of perceived effort appropriate? So far (about 3 weeks of every other day training) I feel ok the rest of the time, fully recovered by the day after but some intuition or something keeps nagging at me that maybe I am going a bit too hard.

    Any advice greatly appreciated!

    Thank you

    • Geoffrey:

      I doubt it. I haven’t heard anyone needing a further reduction of their MAF HR, unless indicated by laboratory tests of their aerobic threshold. That said, there could be other reasons someone can’t train at their MAF HR because of cardiovascular issues, but that’s an issue for the cardiologist or various other specialists.

      On another note, perceived effort is actually very poorly correlated with training intensity, except at very high levels of exertion. Perceived exertion corresponds primarily to how hard the muscles are working. If your ability to burn fats is very small relative to how hard your muscles can pump, your MAF HR will occur at a very low exertion. As your ability to burn fats increases, it corresponds to a greater proportion of your muscles’ contractile ability, increasing the perceived exertion at your MAF. In other words, a fitter athlete will be both faster and experience a higher perceived exertion at MAF.

  • Shey Doane says:

    I have been running utilizing the MAF method for 12 weeks (injury free and feeling great) and have several weeks at 35-40 miles. I’d like to begin integrating some HIT into my workouts but would like some advice where to begin. In the past I’ve utilized Yasso 800s and 3-4 mile Tempo runs, but I don’t won’t to derail the aerobic expansion process by doing too much too early.

    I’ve completed several 50 mile & 100k ultras, but I’m training for my first 100 miler and am a little nervous. My weekly mileage will max out between 60-65 miles (~12 weeks in the future). Should I wait to do some HIT sessions until I get to 50miles/week, or is one HIT session bi-weekly okay, or even beneficial for that matter? If HIT could be recommended, are there any limitations I should observe?

    Thanks beforehand!

    • Shey:

      It’s a safer strategy to wait to start HIT until you max out on your mileage, just in case. The thing is that your 100 miler will depend so heavily upon your aerobic system that you’re probably better off just training MAF in various contexts (flat, trail, roads, hills, etc.) and supplementing with some whole-body and particularly lower-leg strength training. But a HIT session every couple of weeks is reasonable.

  • Gin Sling says:

    While I practise a vegetarian diet that excludes starchy and refined carbs, and I did start out retraining following MAF guidelines, after taking a VO2Max, lactate, and RER test recently, I have since changed my training away from MAF. I’m one of the exceptions that most likely proves the MAF rule, because I have a much higher heart rate than predicted by age, and at which my anaerobic threshold occurs, while still being fat-burning. OTH, I introduced a friend to MAF who has seen spectacular results in a couple of health indicators, such as lowered cholesterol, lowered blood pressure, and enjoying exercise. So it’s not one size fits all, but for most people most of the time, it’s a commendable way to build healthy fitness or recover from overtraining.

    • Gin:

      Interesting. At which heart rate does your maximum rate of fat burning (fat max) occur? Also, your VT1?

      • Gin Sling says:

        Hi Ivan,
        back home with access to my numbers.

        VT1 RER = 0.78
        VT1 HR = 169

        VO2max peak = 53 ml/kg/min
        VO2max peak RER = 0.94
        VO2max peak HR = 182

        Sorry but no data on max lipid oxidation. I had a stress ECG and ultrasound last week and it’s confirmed I have an atrial secondary pacemaker which takes over when I’m not exercising – the secondary pacemaker runs at 70-90 bpm, but the sinus takes over sometimes during sleep (resting bpm is 42) and always during exercise.

        I’m female, 50, 53.6kg, 19% BF. I train pretty much all my runs fasted, haven’t trained distances beyond half marathon yet. Volume varies weekly from 80km up to 110km. I run most of my runs with an RPE of easy, but increase cadence going up and down hills. The one thing I would like is to increase my muscle mass so will be adding in more strength training (and trying to increase my protein intake). End goal is to run ultras, but need to put a marathon under my belt first.

        • Gin:

          Based on those numbers, I’d expect your MAF HR to be somewhere in the neighborhood of 160-165. What I would do is test it out in long runs (16+ km). You should be able to run at least a few back-to-back runs with no hint of stress, becoming irritable, tired, craving sweets, or uncharacteristic muscle soreness or exhaustion. That way, you can be reasonably sure that you’re running under your MAF HR.

  • Gin Sling says:

    Hi Ivan
    thanks for your questions. My beginning RER (carb/fat) was already at an HR above the MAF age-predicted HR – I started the VO2Max test at a higher RER (fat-burning) than predicted as well. I don’t have the results with me (travelling) but will check the VT1 when I’m home again. Happy to post the lot then. I didn’t hit a VO2Max either, but a peak, nor did my RER hit 1 at the time of the peak (that’s more to do with my unwillingness to train with ‘burn’ – so when it’s start to feel hard I always back off. in the case of a treadmill VO2Max test, that meant stopping – another way of putting it is that I’m inherently lazy 🙂 ).

    • Gin Sling says:

      Hi Ivan
      thank you very much for the feedback and I will do exactly as you suggest for the next few weeks and let you know how that goes.

  • Rachel Hayes says:

    Hi Ivan,
    I’m 57, female, 128 pounds. Resting heart rate about 54. Been running for four years, but pretty slow at race pace of about 10:30-11:30 minute miles (Half at 12 minute miles). The 220-age thing just doesn’t work for me. My heart rate has been up to 200, even a big higher at 207, at the end of some of my races, with no nausea, fainting, weakness – just really tired and spent. All my training runs, even at 12-12:30 minute miles, my heart rate is usually in the 160’s. Tried MAF with 220-age, but my heart rate can get up over 122 with just fast walking. I set my Garmin to let me run in the 130-150 range, considering my maximum of 200, and I was still about a 14 minute mile. I am wondering, given my max, is that right to help me get faster? I do have some kind of “normal” for me accelerated sinus thing in my heart, always had it with no issues. Just had a physical and I am in great shape, good cholesterol, sugar, blood pressure. Any advice is appreciated. Thanks, Rachel

    • Rachel:

      Very hard to say. If you think the 180-Formula doesn’t work for you, I recommend that you do laboratory tests to figure out your aerobic threshold. Usually, the people whose MAF HR/aerobic threshold is higher than the 180-Formula estimates are already very fast at their 180-age HR. It’s people who are relatively slower for who the 180-Formula tends to be right on target.

  • Peter Shields says:

    Hi, I am a long time runner and just coming up to my 70th birthday. I take tablets for my thyroid and have been doing for a number of years. 3 years ago I was diagnosed with CLL( Chronic Lymphocitic Leukemia) I’m on a wait and see ( no treatment) and hope to keep that way, monitoring every 4 months.
    I have a very low heart rate and have always been that way. I’m very keen to follow the 180-70 schedule but am a little unsure what hr I should run at. Any advice would be much appreciated.

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