An Hour of Daily Exercise Helps Ward Off Weight Gain in Middle-Aged Women

Patients may ask about a widely reported JAMA study suggesting that 1 hour of moderate exercise daily is needed to prevent weight gain in middle-aged women.


Roughly 34,000 women (mean age at enrollment, 54) in the Women's Health Study answered questionnaires about their weight and exercise habits at baseline and periodically over 13 years' follow-up.


After adjusting for reported diet at baseline, researchers found that over any 3-year period, women who exercised <150 minutes weekly or 150 to <420 minutes weekly were, respectively, 11% and 7% more likely to gain 2.3 kg (5 lb.), compared with women who exercised ≥420 minutes a week.


The authors point out that the association was observed only among women with a body-mass index less than 25, noting that "among heavier women, there was no relation, emphasizing the importance of controlling caloric intake for weight maintenance in this group."


JAMA article