How accurate are these things? I've heard that the calorie readouts on exercise equipment for ellipticals, stairclimbers, etc can be quite inaccurate and that you really burn only about 50% of what the readout actually says even if you put in your gender, weight, and age.

I don't know about the pedometer readouts, but I've checked the machines at my gym against my Polar HR monitor, and they're actually not that far off. For HIIT, they're a bit on the low side, but within 3%. For steady state cardio, they're about 5% too high.

I imagine it varies quite a bit from machine to machine, though. I've just checked stairclimbers and ellipticals.

Also remember that it varies from person to person (even though you may have entered height, weight etc.). Your metabolism will be different each day, and the more you get used to an exercise, the more efficiently your body does it (by efficient I mean burns less calories).

The thing to remember, however, is that it is good motivation to see for yourself that your are burning calories.

Mike.