Did you know?

According to this CNN article, which discusses the accuracy of the 'calories burned' counters on workout machines, "the number of calories the machine indicates that you have burned is not exact...More often than not, the machines will overestimate by as much as 30 percent, though an overestimation of 10 percent to 15 percent is more likely."

Check out the article for good ways to get a more accurate estimate :).