Why calorie counters on treadmills and elliptical machines aren't as accurate as you may think

If you’re trying to lose weight, don’t trust the calorie readout on ellipticals and other exercise machines. Research shows these machines may overestimate the number of calories burned in a 30-minute session by over 100 calories. Stationary bikes typically have the most accurate readouts, followed by stair climbers, treadmills, and ellipticals.