The Zoomer Report: How Much Exercise?

Zoomer | March 31st, 2010

What would it take to prevent weight gain in mid-life? Researchers have it down to a science – at least for women. Here’s the prescription according to a study in the Journal of the American Medical Association.

An hour a day of moderate-intensity exercise will prevent weight gain in normal-weight women, who are middle-aged and older. That means brisk walking, casual bicycling, ballroom dancing, even playing with your grandchildren. The study authors say this is enough for someone who wants to eat normally.

On the other hand, if you do something more vigorous — like jogging, playing tennis or swimming laps — you can get away with 30 minutes a day and you still won’t gain weight as you age.

There’s been lots of research on how to help people lose weight, but very little has focused on how to prevent weight gain in the first place. The researchers wanted to do that because most people re-gain the weight they lose.

They followed 35,000 women, who averaged 54 years old at the start of the study, for 13 years. Those who exercised an hour a day gained less than five pounds in that period. But they don’t want people to feel discouraged if they can’t do 60 minutes a day. Bottom line: Everyone should exercise as much as they can.