Using the generic formula of 220bpm minus is your age to find your max heart rate is completely inaccurate. If you are working out according to the formula, you are doing it wrong.
Myzone automatically calibrates and finds your TRUE MAX Heart Rate which is 99.4% accurate.
What does this all mean? This means that if you are training at 80%, this is an accurate and true reflection of your effort levels.
You earn MEPS (Myzone Effort Points) while you train. The longer you stay in the higher heart rate zones, the more MEPS points you earn. Effort based training means that young and old, fit and unfit, male and female, can all compete against each other.