101 MAF Heart Rate Zones

By April 30, 2015 June 13th, 2017 Exercise

Thirty-five years ago, while developing the 180-Formula, MAF Test and other key endurance approaches, the first training zones included only two: One being aerobic, the other anaerobic. Simple.

As heart-rate monitoring became more popular, others started creating various exercise heart rate zones. These were often based on some percentage of VO2 max, even though few athletes actually underwent this test in a laboratory. Others used “maximum heart rate” as a guide, and although this determination also was quite random in respect to individuals, it quickly and unfortunately became the foundation of most formulas.

Meanwhile some athletes simply make up their own zones, which seems to defeat the purpose of a zone. And of course, there remains the majority of exercise enthusiasts who don’t even think about their heart rates when training, and just go do it. This can result in training benefits or overtraining issues very similar to those obtained by using the subjective zones that have become popular.

In addition to heart rate numbers, some zones are represented by commonly used exercise terms, such stamina, recovery, endurance, cardio and others. These typically have no real scientific definitions but are just social images with no definitive meaning. (Of course, the terms aerobic and anaerobic are also not defined appropriately by the mainstream: See “Think you know what aerobic means?”)

It did not take long before I realized my two original zones were actually much more complex than that. Based on the neurophysiologic response to exercise — in particular, the specific nerves and muscle fibers being associated with each rise in heart rate and level of exertion — it was clear there were dozens of zones. In fact, each individual beat is sort of a zone unto itself.

Consider that you’re heading out the door for a workout. With a starting heart rate of, say, 54, you begin walking faster bringing the rate to 72. As you start jogging slowly, you reach 87 and gradually speed up based on how your body feels. After about 20 minutes and now running at a faster pace, you reach your MAF HR of 155 and are feeling great. These are the 101 heart rate zones, at least in this runner’s case.

By slowly increasing your heart rate from resting up to the MAF zone, you have just gently gone through the full spectrum of nerves that, when stimulated, contract important muscle cells, or fibers. The entire process, including the actions of the nerves, muscles, and heart, is controlled by the brain.

If you want the best workout, gradually raising the heart rate is important. This stimulates all the nerves and contracts all the muscle fibers along the way as well.

HR Jumping

When working out in zone modes, however, athletes often jump from one zone to another, skipping many of the training benefits for certain muscle fibers. This “jump” phenomenon, despite the explanation that a particular zone has a spectrum of heart rates that blend into the one above, is common. I discovered jumping years ago. It was easy to see when observing a runner on the track. More objective evidence became possible when more sophisticated heart-rate monitors allowed us to evaluate an athlete’s beat-to-beat workout by uploading the data. Without slowly raising the HR so that all beats were part of the workout, most would literally jump from 120 to 130, for example, or 145 to 165. Likewise, during the end of the workout when the heart rate should gently descend, athletes would often jump down to the workout’s end. This is something to be avoided.

Now we know that by not stimulating a variety of muscle fibers, each innervated by a different nerve and commencing at a particular place in the brain, jumping can lead to an incomplete workout. There’s another serious problem with jumping: It tends to reduce one’s warm-up and cool-down capabilities.

Two Key Training Components

Every workout, whether easy or hard, and each competition, should begin with an active warm-up. Too many athletes jump through this preparatory phase of training. This prepares the body for the most efficient and safest workout possible. The warm-up increases fat-burning and circulation through the muscles, raises the lung capacity to increase oxygen uptake, improves flexibility, helps process carbon dioxide, and generally increases body temperature to signal other necessary metabolic actions that are very important. No athlete wants to skip this step.

Cooling down is vital too. It serves as the first stage of recovery from the workout. Even competition deserves some kind of cool-down to help start recovery, even if it’s just walking around the finish area. An active cool down sets the pace, so to speak, for the body’s recuperation process over the next 24 to 48 hours or more. This too is something we all want to take advantage of at the end of each workout.

Imagine you are in a jet taking off. You slowly ascend for about 15 minutes or more. This is like a warm-up enabling you to reach a cruising altitude. You maintain that level for a period of time, which is like the middle part of your workout, say at your MAF HR. About 15 minutes or more before landing — before the workout ends — you start your descent. By slowly bringing down the HR you land safely and begin your important recovery process.

By slowly ascending to your workout level, whether it is an aerobic or anaerobic one, and properly performing a cool-down, you go through all the heart rates along the way rather than jumping from zone to zone. This makes each workout highly efficient.

The only important distinction that needs to be made is whether you want the workout to be aerobic or anaerobic. Either way, you still slowly elevate the heart rate to a certain level, maintain it (or apply some variation in pace and heart rate), then return, stimulating all the nerves and muscles via the brain to obtain a comprehensive workout. This provides a complete aerobic workout, or a complete anaerobic one.

So there are really still just two simple zones, unless you want to count your heartbeats.


  • Fred says:

    When I skip warmup, my breathing increases at a lower heart rate. I believe that means I’m going slightly anaerobic even below my MAF heart rate. I’ve also had sneezing fits in the past by skipping cool down, though that was after anaerobic workouts. I’m convinced now that warming up and cooling down are very important.

  • Chandra says:

    Hello, I’ve read a few of the comments above and found them helpful. Thank you! I’m new to heart rate training and would like to get a solid aerobic base for my first 50k. I had no idea how high my heart rate jumped when I start running, I wonder if this is why I haven’t made much progress? Also, along the lines of some of the above comments: I’m trying to keep my HR under 144 so I have to walk every 30 second or so. At a fast walk my heart rate stays very low but the moment I start a very slow job my HR jumps up! I start walking as soon as it gets to 139 but for a few seconds it will keep rising all the way to about 150 before it drops back down. So my question is this, are those few seconds spent above 144 going to impair my aerobic base training or is it just a number that I shouldn’t obsess too much about?

  • Steve says:

    The MAF aerobic threshold formula, I believe, is derived from a broad statistical data, with room for corrections for people who deviate from the norm. If I am to determine my “true” aerobic threshold heart rate (at a given time with given physical conditions) through an experiment with data aquisition, what would I have to do? Would it be the heart rate at which my blood sample start showing traces of lactic acid? I do not think this is a mandatory sign because lactic acid will start to come and go (recycled for aerobic respiration) while my body is still mostly in aerobic state, in which case it could have actually passed aerobic threshold. In other words, absence of lactic acid in a small blood sample does not guarantee that I am 100% in aerobic state. That’s just my thought.

    Assuming if I had all the apparatus and resources, what would be the best indicator to determine my true aerobic threshold heat rate appropriate for aerobic conditioning as outlined in this article?

  • Andy Brophy says:

    I’m 54 yrs and have been walk/running at least 3 times a week for the last 14 months. Ive set my HRM at 116-126. Ive just downloaded the MAF app and have a question about the wording of the parameter guidelines. It says stay within 10 beats of MAF number without going over for best results; is that 116-126, or is that 116-136 as an acceptable range?

  • Geoff says:

    Is a high maximum HR a sign of excess life stress (physical, chemical, or emotional)? My lab tested maximum HR is nearly 200 bpm yet my MAF heart rate (with appropriate adjustments) is in the low 130s. My MAF training pace is quite a bit slower than the pace I could maintain comfortably for 2+ hours at a higher HR. Presumably this demonstrates that my aerobic function needs improving, but is there cause for concern that my max HR is “too high” because of stress? Would stress reduction also reduce my max HR or is max HR truly “just a number” and nothing more?

  • Lou says:

    So are you saying if I am above 180 minus my age I am anaerobic regardless of how high above?

    • Lou:

      No. Let me explain:

      1) The 180-Formula consists of more than 180-Age. There are several modifications to be made to the number depending on your health and fitness status. So 180-Age might be 10 BPM lower or higher than when you start being anaerobic.

      2) The 180-Formula is a quick way to approximate the point at which anaerobic function starts. Laboratory tests (such as Fat Max) give you a completely precise indication of where your aerobic function starts (which is known as your aerobic threshold).

      3) In this vein, the aerobic threshold is where anaerobic function starts. So anaerobic function increases the further you go beyond your aerobic threshold, and it takes over when you go past your anaerobic threshold. In effect, while you are functioning anaerobically both over the aerobic and anaerobic thresholds, the magnitude of that anaerobic function is quite different.

  • Todd Perkes says:

    My number is 130. I usually do a run/walk ratio of 8 minutes run to 2 minutes walk. I am training to run a 60 mile road race this summer. Is this recommended. I find when I am walking my heart rate drops to low and when I am running it gets to high. Or should I just be running slow and keep my heart rate consistent. Plus how much should my heart rate fluctuate. it is hard to keep at at one number. I have ordered a book and maybe some of that information is in it. Thanks

  • ken says:

    180 -69= 111 do I add 10 heart rate for 121. I’m in good heath. I take no medical issues.

  • Brian Donovan says:

    Having recently read (from cover to cover) Phil’s book, ‘The Big Book of Health and Fitness’ (great, great book, by the way), I am quite interested in learning more about my heart rate during all forms of exercise.
    My question is: can anyone here recommend a good, and reasonably priced, heart rate monitor for use in walking/running? GPS is not an issue for us as coverage here is quite bad. I’m more interested in reliable and robust monitoring of heart rate.
    Any suggestions?

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