Monday, February 18, 2013

MAF Math

So with all the talk of the MAF system I've been seeing lately, I decided to do some tests on myself comparing various heart rate estimation formulas with an actual submaximal talk test.

What I like about the MAF idea is the simplicity of the math. The formula I had seen the most before hearing about MAF was to estimate your maximum heart rate with 220-your age. Then to get your aerobic zone you multiply that number by .7 and by .8. Between those two numbers is your aerobic training zone. That is sort of hard to calculate in mid run. MAF makes it easier by just using 180-age to be your maximum number for your aerobic zone. Much simpler calculation.

To make it worse, the formulas considered to be more accurate are more complicated.

Here are the formulas I played with this morning and the results rounded to whole numbers.

(220-age).8
146

MAF 180-age
143

(208-.7*age).8
146

The one considered most accurate: (205.8-.685*age).8
146

Then I got on the treadmill for a submaximal talk test.
My final result (one test only not an average of 2 or more tests)
147.

So, while the MAF calculation was the  least accurate  for me, it is close enough that I could use it for an indication of my aerobic training zone. Keep  in mind that this is only one test on only one person.

Something more important that I learned doing this that makes it even simpler for me. I can tell when I've gone past the aerobic zone just going by feel. So I will continue doing what I've been doing and not worry about checking my heart rate repeatedly.

My recommendation based on my extremely limited science today is to use a heart rate estimation if it helps you figure out your pace, then start learning what it feels like on either side of the aerobic line. If you can learn to go by feel, you can keep your mind off your heart rate monitor and just enjoy the run.