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The Difference Between 3 Days of Exercise a Week and 5? It's Not What You Think

The big picture: Going from moderately active to super active doesn't make much difference in your daily calorie burn.

The science: Researchers looked at the daily activity levels and energy expenditure of more than 300 people to see whether higher levels led to a bigger burn. In their study, published earlier this year, they found that going from sedentary to moderately active (think exercising a few days a week and taking the stairs when you can) helped burn about 200 more calories daily, but the jump from moderately active to very active didn't change the daily burn, possibly because our bodies compensate by spending less energy on essential tasks like immune function and cell repair, explains lead author Herman Pontzer, PhD, a professor of anthropology at Hunter College in New York.

What it means for you: You still have to work out, but going to the gym every day probably won't help you shed the weight any faster. (Remember, there are many mental and physical benefits to exercising, beyond the number on the scale.) Do as Pontzer does and "exercise for your health and watch your diet to watch your weight."