The more you age, the more you'll need to work out

(NBC) - A new study in JAMA shows for normal weight middle-aged women and older who eat a regular diet, 60 minutes of daily exercise is recommended just to maintain weight as they age.

For overweight or obese women exercising 60 minutes wasn't enough to maintain and not gain weight.

"If you want to prevent your weight gain over time you need to be physically active at the level of 60 minutes of moderate intensity physical activity," said Dr. I-Min Lee, a researcher at Brigham and Women's Hospital who co-authored the study. "So the equivalent of one hour a day of brisk walking or 30 minutes a day of jogging or running."

For heavier women researchers say not to let the 60 minutes discourage you from starting or continuing to exercise.

The study shows any exercise helps reduce the risk of chronic diseases, including heart disease, cancer and Type II Diabetes.

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