Yet, if Americans were following federal guidelines for physical activity (150 minutes a week of moderate-intensity exercise or 75 minutes of more vigorous activity), those extra calories would have been evened out.
Only one in four Americans is doing the recommended level of exercise, the authors stated.
"We need to encourage physical activity even more, especially given that we sit more during the day than we did 100 years ago," said Keri Gans, a spokeswoman for the American Dietetic Association and author of The Small Change Diet.
"The demands of everyday life are competing with exercise," Graham added. "We just have to make time for it."
Gans recommends that people move at work even if they have what amounts to a desk job. That could mean taking the stairs when you can, walking over to a co-worker's desk when you can and going for a walk at lunchtime. And if your company happens to have a gym or exercise program, by all means, partake.
The U.S. Centers for Disease Control and Prevention has more on how to get moving.
SOURCES: Keri M. Gans, R.D., spokeswoman, American Dietetic Association, and author, The Small Change Diet; Robert Graham, M.D., primary care physician, Lenox Hill Hospital, New York City; May 25, 2011, PLoS ONE, online
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