I first learnt about Phil Maffetone and his work in 2009.
I stumbled upon his book, The Big Book Of Endurance Training And Racing, as I tried to learn more about fat burning and how you could increase an athlete’s ability to generate energy from fat.
I had moved to Singapore in 2008 to pursue my coaching career, and soon after that opened our first high-performance lab where we started doing a lot of metabolic testing.
Early on, it became clear that most of the athletes we measured were heavily reliant on carbohydrates and not good at burning fat. Many had excess body fat and had trouble in the later stages of races. These issues are a problem, so I searched for the factors that influence fat metabolism, hoping to transform people into metabolically flexible fat burners.
After reading Phil’s book, I knew we were on the right track.
I grew up in New Zealand and was exposed to the benefits of aerobic training at a very young age. Arthur Lydiard had pioneered the approach to training endurance athletes with a lot of aerobic volume, and most coaches Downunder had adopted his approach since the 1960s.
It served me well – with a sprinkling of high-intensity training, of course – throughout my pro career, and I was comfortable prescribing aerobic training and having athletes use a heart rate monitor as an objective measure of intensity.
What I was less familiar with at the time was the role nutrition played in fat burning, health and performance.
What Is MAF Training?
Simply put, MAF training is a philosophy about how to train and a set of tools Phil developed to help athletes perform better.
MAF stands for maximum aerobic function, and the idea with MAF training is to train at, or below, your MAF heart rate ceiling to improve your aerobic function and increase your fat burning ability.
As Phil says, “there are a lot of fit but unhealthy athletes”, and this is primarily the result of too much intensity in training, a poor diet rich in processed carbohydrates, and high overall stress levels.
MAF training and the tools Phil designed are a response to those problems.
The 180 Formula
The 180 formula is a formula for calculating your MAF heart rate. It’s a simple calculation where you deduct your age from 180. You then add or subtract from this number based on several lifestyle factors that Phil has set. The end result is a heart rate ceiling that you do all of your training at or below.
Phil states that this heart rate is suitable for everyone and is the same across sports. I like this formula, and we use it a lot in our programmes, but I disagree that it works for all and across sports.
Lactate and metabolic testing are far more accurate ways of determining training zones. As we’ve seen many times in our lab, an athlete’s actual MAF heart rate often differs significantly compared with the formula heart rate.
The MAF Test
To track the progress of your aerobic development, Phil created the MAF test. The MAF test is a simple test performed at the MAF heart rate. At Coached, we mainly use it as a running test, but you can also do it on the bike and in other ways.
We aim for the test to last around 40-minutes. That means that you’ll be running somewhere between 4 – 8km for most athletes depending on your fitness level. Once you have determined the distance you wish to run, you run at your MAF heart rate to completion. As you run, your pace slows in response to fatigue. This decrease in pace is normal and expected; however, aerobically fit athletes will slow much less than someone unfit.
Over time, with the proper training and lifestyle habits, you’ll see that your pace at MAF heart rate improves. Below is an example of one of our athletes over five months.
