Originally Posted by velocity
I look at it like this first you need to know what your max HR is (stress test) and not based on any formula.
I' want to make the general comment that max. heart rate is not a very useful number for training purposes any way. The important number is lactate threshold. All heart rate training zones are relative to LT, or sometimes VO2max.
A brief description of the zones, relative to LT:
http://www.ultracycling.com/training...ing_zones.html