How accurate are the calorie-expenditure readings on treadmills, steppers, etc...?

Answer 1

Basically they give you only a generalization. They only take into account your weight.....not your stride length, height, frame size. They are good for a generalization but not for specific information.

Answer 2

Not very. Studies show that they can be wrong by as much as 45%, though most are accurate within 10-15%. Even the best ones are far from perfect, because there are so many factors that go into burning calories. The truth is that it varies from person to person, so these things CAN'T be accurate. They really are only measuring averages.

Answer 3

It's only an estimate.