The MAF method, short for Maximum Aerobic Function, is a third option for determining Aerobic Threshold (AeT). It’s quick, easy, and we promise that you won’t break a sweat! This is a method that we recommend for those who have never engaged in organized aerobic training. It uses a simple formula that Dr. Phil Maffetone developed over 30 years ago. The MAF method gives a conservative estimation of an individual’s AeT. With this method, your aerobic base training will be most effective if you use the resulting number as the top heart rate for Zone 2.
The calculation is simple: Subtract your age from 180 and you have your MAF heart rate.
A 30-year-old would therefore use 150 beats per minute (bpm) as the upper limit of their aerobic training zone. To say it another way, this athlete would consider their aerobic training zone to be 130–150.
You can adjust the formula depending on your training history:
- If you are injured, have regressed in training or competition, get more than two colds or bouts of flu per year, have allergies or asthma, or if you have been inconsistent or are just getting back into training, 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 just mentioned, keep the number (180 minus your age) the same.
- If you have been training for more than two years without any of the problems listed above, and have made progress in competition without injury, add 5.
For a full rundown of Uphill Athlete’s recommended methods for determining AeT and AnT (Anaerobic Threshold), read “Aerobic Self-Assessment for Mountain Athletes.”