Stronger Muscles, Stronger Brains

Study shows lifting weights just once a week helps keep your brain sharp

by: Candy Sagon | from: AARP Bulletin | January 4, 2011

En español | For older women, the type of exercise you do may be more important than how often you do it.

That's the message of a surprising new study by Canadian researchers that found that women who started a once-a-week strength-training program were more likely to stick with it — and reap the physical and mental benefits — than those who started a twice-a-week program.

Exercises that build muscle strength may also improve mental focus. — Charriau Pierre/Getty Images

More importantly, older women who built muscle strength through biceps curls, leg lifts, squats and the like showed much greater improvement in mental focus and ability to make decisions and resolve conflicts than women who did only balance and toning exercises.

Published this month in the Archives of Internal Medicine, the study is a one-year follow-up of 155 women ages 65 to 75 who participated in an earlier strength-training exercise program in 2007-2008.

Weight training and the brain

The women in that program were randomly divided into once-weekly and twice-weekly regimens that used dumbbells, weight machines and free-form exercises like squats and lunges to build muscle strength. A control group performed twice-weekly balancing and toning exercises, but no weight lifting. At the end of the 12-month program, both the weight-training groups showed sharply improved mental focus. In the control group, mental function slightly declined.

A year later, researchers again tested the women to determine who had maintained their physical activity level as well as the mental boost they had gotten from exercising during the original program.

"We were very surprised to discover the group that sustained cognitive benefits was the once-weekly strength-training group rather than the twice-weekly training group," says lead author Teresa Liu-Ambrose of the Centre for Hip Health and Mobility at Vancouver Coastal Health and the University of British Columbia.

Is once a week enough?

Although the twice-weekly group was exercising less a year later, the once-weekly group was still active and showed a 15 percent improvement on their mental skills test as compared with the balance-and-toning group, the researchers found.

Liu-Ambrose believes it's because the once-weekly group found it easier than the twice-weekly group to maintain the same level of physical activity of the original study. "Those who start a once-weekly strength-training program are more likely to stick with it," she says.

In other words, while exercising more often may ideally be better for you, ultimately the best exercise program is one that you actually will keep doing.

Strength-Training Tips

Lifting weights just once a week offers brain health benefits. — B2M Productions/Getty Images

Do a single set of repetitions. Just one set of 12 repetitions with the proper weight can build muscle as efficiently as multiple sets.

Equipment? Use elastic bands, dumbbells or weight machines.

What's a proper weight? One that's heavy enough to tire your muscles by the 12th repetition. You should just barely be able to finish the last one.

Start slowly. Start with only a few pounds — or the easiest band — to get your muscles, tendons and ligaments accustomed to weight training. Once you can easily do 12 repetitions, gradually increase the weight.