Maximum Aerobic Function – Ego, Injury, Dr Phil Maffetone, Most Shared Ebook, HR: 180 Minus Your Age, Personalisation, Longevity.
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For someone who thought they knew a fair bit about health and fitness, I’ve had to completely rewire my approach to training in the last few years.

My old approach was built on sayings like:

  • More is better.
  • No pain, no gain.
  • Go hard or go home.

It was about toughening up with sets of 10 x 200 metres freestyle on 3 mins wearing a t-shirt.

I have a clear memory of diving off the blocks in a sprint swim set with the absolute intention of going so hard that I’d make myself vomit.

Even at the 2003 Water Polo World Championships in Barcelona, rather than recovering on our rest days, I’d hit the gym because I was telling myself that “it wasn’t the Olympics”.

It wasn’t just me though, it was coaches at the time too.

And there’s only one word for it.


It nearly cost me my Olympic spot.

In January 2004, my huge training volume ended up with inflammation of my adductor muscles 6 months out from Athens that put everything at risk.

Fortunately I had incredible physiotherapists to help – Victor Popov and Ed Fitzgerald. I got through it, competed and thankfully have never had it recur.

I look back now at that time and approach and can see the delusion. There was no science behind it, just an obsession with more is better.

But I didn’t really learn my lesson.

Then life’s curveballs began to pile up:

  • Two knee operations from a dislocated knee cap snowboarding in 2008 (arthroscopy) and a subsequent repair job in 2014 (mosaicplasty).
  • A full shoulder reconstruction from throwing a ball as hard as I could for 20 years in 2016. (Gory details: bicep tendon slap tear, tears to my rotator cuff and labrum and bursitis.)
  • And most recently, hamstring tendinopathy from getting a little too enthusiastic when I started karate 2 years ago. That meant scans, injections, misdiagnoses, periods of excruciating pain. The rehab is still going on today.

And they were on top of baseline lifestyle changes like sitting down for long stretches each day at work and trying to squeeze in exercise amidst the competing time demands of family life.

What springs to mind are the immortal words of Captain Tom “Stinger” Jordan as he was talking to Maverick, played by Tom Cruise in the scene from Top Gun:

“Son, your ego’s running cheques your body can’t cash.”


I’ve become so fed up with cycle of injury, rehab, train, breakdown again, that I just had to try a new approach to health and fitness improvements.

As I’ve laboured under the compound effect of all of the injuries and lifestyle, I’ve been forced to rethink how I train.

How can I rebuild and then develop my physical health for the long term?

How can I stay focussed on the present to benefit from the compound effect of staying fit and healthy and not falling back into injury?

These are tricky questions. No one size fits all.

But I was recently introduced to Dr Phil Maffetone’s Maximum Aerobic Function system.

It’s evidence based, quick to personalise, easy to get started and simple to maintain.

Dr Phil Maffetone & The Maximum Aerobic Function (MAF) Method

Dr Phil Maffetone has quite a rap sheet:

Over the course of his career, Dr. Maffetone has worked with some of the world’s finest athletes in a variety of sports, most notably Mark Allen, six-time Hawaii Ironman Triathlon Champion. Dr. Maffetone has also worked with other endurance athletes of all types, professional baseball and football players, adventurers, NASCAR drivers, and Olympic medalists in a variety of sports. While his work with top-level athletes reads like “Who’s Who,” perhaps more notable, Dr. Maffetone has helped thousands of weekend warriors achieve personal-best performances in their chosen sports.

Outside the sports arena, Dr. Maffetone has coached a variety of people in the entertainment field, including musicians James Taylor and Johnny Cash, The Red Hot Chili Peppers, and producer Rick Rubin, and has also provided a system of success for some of the world’s top business executives as well as the United States military.

And his experience is backed by clinical scientific evidence. (You can find his research papers here.)

Why MAF works (An excerpt from Dr Maffetone’s e-book The MAF Method)

I have written about the key components of MAF for decades. This chapter addresses the why. Just why does maximum aerobic function work? With a strong clinical and scientific foundation, the goal of MAF is to help individuals personalize their food, exercise and other lifestyle routines to address causes of problems not just treat symptoms, leading to real, lifelong benefits.

These are not commandments, rules or laws, but basic explanations of a holistic approach to health and fitness I began developing in the 1970s.

Here are nine short points:

    1. As an overview, the shortest answer is that MAF helps restore the most natural state of human performance. This promotes optimal physical, biochemical and mental-emotional health and fitness.
    2. MAF means maximum aerobic function, reflecting our innate ability to burn (oxidize) body fat for nearly unlimited energy. Reliance on fatburning, a predominant fuel source potentially used for most of our needs, occurs in the cell’s mitochondria, found in muscles, including the heart, kidney, liver and many other areas. Fat-burning also increases production of ketone bodies, useful for energy by the brain and throughout the body, and helps keep energy high, and blood sugar and glycogen stores stable. Maximizing natural fat-burning is a key focus of MAF, directly improving all areas of health and fitness.
    3. The earliest humans maximized fat-burning as an essential part of developing better and bigger brains and bodies. It led to increased longevity and more functional aging, protection against chronic -illness, physical speed and endurance, and prevention of excess body fat. In a real sense, max aerobic function is how humans advanced so well from the beginning. We possess this same physiology today, unless poor lifestyle interferes with it.
    4. Poor food or exercise choices can significantly impair metabolism and reduce fat-burning. Energy wanes leading to a wide array of abnormal signs and symptoms from fatigue, hunger and depression, to excess body fat and weight. This can lead to poor blood lipid profiles, high blood-sugar levels and other common risk factors, ending with chronic illness, physical impairment and reduced quality of life. MAF offers strategies that help people figure out the causes of these problems, and their solutions.
    5. Our aerobic system is where most fat-burning occurs, especially in the slow-twitch aerobic muscle fibers. These non-fatiguing endurance muscles support joints, bones, ligaments, tendons, and anaerobic fibers, promote efficient posture and movement, prevent injuries, and are vital sources of circulation and antioxidant protection. When this system is faulty, it leads to an aerobic deficiency — poor fat-burning and increased fat storage.
    6. As a natural holistic approach, MAF considers all physical, biochemical and mental-emotional aspects, and how lifestyle stress impacts us. Included are the physical muscles, bones and joints, biochemical hormones, nutrients and neurotransmitters, and mental-emotional cognition, learning, memory and pain. When well integrated, optimal human performance on all levels results.
    7. Various MAF tools help people understand abnormal signs and symptoms, find the causes of reduced health and fitness, and personalize lifestyle remedies. It begins with a simple process of selfassessment. These tools include online digital evaluations that guide the process, the MAF Test, a measure of physical activity at specific heart rates, and the Two-Week Test that helps determine foods that best match a person’s needs.
    8. Measurable improvement is an important goal of MAF—not just the elimination of symptoms but enhancing human performance. As such, MAF has been popular with people of all ages seeking weight and fat loss, athletic performance, corporate and academic improvements, addressing physical impairment, including body and brain injuries, those in rehabilitation, and others.
    9. Through the process of self-assessment and monitoring, the MAF Method helps take the guesswork out of eating, exercise and stress to continually improve health and fitness. A simple ongoing monitoring system, one that will become intuitive for you, helps ensure progress is made and maintained to prevent relapse.

Where to start

If this interests you, here are two possible approaches:

    1. Dive straight in to the whole framework. Download the MAF Method Ebook. It’s the one health resource that I’ve shared most this year. It explores nutrition, exercise and stress and will help you personalise your approach.
    2. If you’re looking for a quick start, the MAF heart rate based training heuristic below is what I found helped me take immediate action.

Heart Rate Zones

Heart rate training zones are nothing new.

Google it and a bunch of tables in beautiful colours pop up with tabled heart rates to train at with accompanying recommendations like: “It should be a struggle to talk.” But that’s a tricky thing to measure and be accurate with when it comes time to actually train. And, those zones don’t take into account anything of my personal situation.

So the ability to quickly personalise heart rate zones to my own circumstances using MAF, without in depth testing and the associated costs… that is something I hadn’t found elsewhere.

Armed with my watch (to measure heart rate) and the below calculation, I began the battle of changing my training habits.

Calculating MAF Heart Rate (180 minus your age)

The part I like most about the MAF framework as a launching point is the quick calculation that gives me a personalised specific heart rate range to target.

To quote directly from Dr Maffetone’s ebook, here’s how you calculate your Maximum Aerobic Function heart rate:

The MAF 180 Formula Determining your MAF HR:

    1. Subtract your age from 180.
    2. Modify this number by choosing one category below that best applies to you:
  • If you have or are recovering from a major illness (including any operation or hospital stay), are in rehabilitation, have been prescribed any regular medication, or are chronically overtrained, subtract an additional 10.
  • If you are injured, have regressed or not improved in training (such as poor MAF Tests) or competition, get more than two colds, flu or other infections per year, have seasonal allergies or asthma, are overfat, are acutely overtraining, or if you have been inconsistent, just beginning or returning to exercise, subtract an additional 5.
  • If you have been training consistently (at least four times weekly) for up to two years without any of the problems mentioned in a) or b), no modification is necessary (use 180 minus age as your MAF HR).
  • If you have been training for more than two years without any of the problems listed above, have made progress in your MAF Tests, and have improved competitively, add 5.

So my MAF heart rate is:

180 – 43 (my age) – 5 (for injuries) = 132

Subtract an additional 10 for the bottom of my target range.

My target training heart rate range then is: 122-132.

When I first saw this number I thought that was insane. It was so counter to my historic approach.

But the MAF guidelines say that given my current physical health, I should be training at this range for 3-6 months before adding in higher intensity again.

Nothing else felt like it was working. So I decided to give it shot.


As of Mar 2023, I’m 4 months into my experiment of training within the MAF guidelines.

When I combine it with my watch to give me the HR feedback, I know in real time if I need to back off or push my training.

By far the hardest part of adopting this has been holding back.

But tracking progress through my watch I’ve seen my resting heart rate drop, my max VO2 increase and most of all I’m finishing sessions feeling better than I started rather than gassed (another core principle of MAF).

Perhaps most importantly, I’ve been able to maintain my basic weekly training for 4 months now:

  • 1 x 2km swim,
  • 2 x supervised pilates sessions,
  • 1 body weight strength session
  • and some walking (at my MAF HR) while on work calls.

I have to practice being present to remind myself though that if I can reduce the load and intensity now, then I’ll give myself a shot at compounding the small gains into being able to do more in the future.

And this is the most sustained training I’ve been able to do in 2 years.

I think one of the keys is having that very specific heart rate of 132 as my upper constraint. Inevitably I bump over it every now and again, and have had set backs, but it’s certainly working for me.

My own experiment continues, so let me know in the comments if you give this a try or have had any experience with implementing it.

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