Are the calories burned on cardio machines accurate?
A. Treadmills and stationary bikes are the most accurate (give or take 7 percent) because there are well-established “standard prediction equations” for the calories burned on them in a given period of time. Unfortunately, other machines such as elliptical trainers, stair climbers and machines that require combined upper and lower body movements don’t have these standard prediction equations. “Often, manufacturers use a single isolated study to come up with the calories burned, which isn’t enough for complete accuracy,” Kaminsky says. He estimates they could be off by as much as 10 percent to 15 percent. This might not seem like much, but it can really add up over time. If you’re working out four days a week and you’re off by 15 percent, you could be burning 800 fewer calories than you think each month. And keep this in mind: if two machines (e.g., elliptical trainer and treadmill) show the same calories burned, but one workout seems much easier, you’re probably burning fewer calories.
