Differences between heart rate monitors?

Last year I used a Timex HRM, mostly because I like the fit of Timex watches. I really only used it when I had a HR-specific interval workout and it seemed to work OK. Since the battery is dead on that I decided to try out my new Suunto one. I was shocked at the numbers...either I'm in better shape than I thought or the numbers are way off. I just kept on eye on the BPM number for reference during intervals.

Do you think the generic BPM funtion varies from watch to watch? I hope this make sense.

I don't know, but you could count your pulse by hand and compare the result.

Maybe you could even wear them both at once?

I'm not sure I could count 175BPM! LOL.

do it in 10 second intervals, multiply by 6 for your per minute rate.

I've used the built in HRM on the computrainer while I've had my regular one on too (a Sigma) and they have not always agreed exactly. In general they were pretty close, but the Sigma would react faster and, I think, was more accurate overall (Sigma also makes ECG equipment for hospitals... they say their consumer products are just as accurate). The computrainer one was often a little lower or a little higher and definitely had some lag time before it catch up to a hr change.

Based on anecdotal 'evidence', I think there are often anomolies between brands/styles of of HRMs.

The important think is the trends in recovery rate, exertion/effort etc which you read on your HRM. If you need to have an accurate measurement taken of your max, or your LT, then use a science lab.

Otherwise, I would suggest don't get thrown by number differences in HRM models, just look for the patterns... these should be similar (eg how quickly your HR recovers to resting, how it responds to hills, or to hammering it on the flat...)