Subject: RE: calculating hr zones I am not a physiologist, but I hope the expanation below will be of sufficient help to you. Your VO2max is the maximum oxigen your body can use during an effort while staying aerobic. It will happen at a given heart rate, which you probably received in the report as well. Any effort above that takes you into full anaerobic effort, therefore into heavy production of lactate. Lactate production increases even during aerobic effort. Lactate Treshold or Anaerobic Treshold occurs when the amount of lactate being produced is higher than what the body can eliminate. Generally that occurs anywhere between 80 and 85% of VO2max. In other words, the HR at which you reached 83% of VO2max is your LT heart rate. From that you can calculate your zones using Friel's percentages of LT. VO2max is a better method only because is a lab experiment, but while VO2max on a trained individual dos not generally change much, LT may vary slightly. Friel's takes into consideration that since nobody can go anaerobic for too long, the average of your maximum effort during an extensive period of time should be the max one can do before going anaerobic, therefore either LT or very close to it. |