I have a student who asked me why his maximum heart rate varied so much from one test to the next. On a one-off occasion his heart rate reached 217 bpm, since, he has ranged between 188-196 bpm. The method he used involved performing 10 x 200 m sprints followed by 200 m recovery jogs. Can anyone explain the variation? Could it be his polar heart rate monitor? I would also be interested in the various field methods used for determining maximum heart rate and people's experiences. Thanks in advance Chris Lorenzen B App Sc (Hum. Mov.)(Hons) -------- View all messages at http://sportsci.org/forum. Click on the links to JOIN, UNJOIN, alter MAIL OPTIONS, or get INFO/HELP on acceptable messages.