If you and Rosie Huntington-Whitely are side-by-side on the elliptical machines, working at the same pace, are you going to burn the same calories? Probably not — but your exercise machine may tell you that you are.
Exercise machine companies base calorie-counting outputs of their treadmills, ellipticals, and most other machines, on estimates created from mathematical formulas involving oxygen use, muscle mass, and effort. Other companies, such as Life Fitness, set up their own labs to test various exercisers’ oxygen consumptions and convert them to calories burned.
However, The American Council on Exercise (ACE) says the amount of calories burned depends on your body size, body fat percentage, fitness level, weight, age, what you ate for dinner last Wednesday and how much you paid for your last pair of Lululemon leggings (OK, those last two really don’t count).
Feeling the Burn
Since the average exercise machine asks for little more than your age and weight, it’s important to view the “calories expended” output as an estimate, not as a license to carbo load with a post-workout doughnut. Ellipticals tend to be especially off, sometimes as much as 20% to 30%, according to ACE. This is because some people use the handles (which burns more calories) and some don’t.
If you’re looking for a foolproof way to calculate your calories burned, you won’t find one…yet. Newer exercise machines tend to have worked out their calculation kinks and are more accurate, as do higher-priced machines. And if you don’t have access to an exercise science laboratory, your best bet is still to base the idea of how much you are burning on your calorie output machine (and your jeans when they start feeling looser).
xx, The FabFitFun Team