When a colleague asked me if exercise might alleviate her menopausal symptoms, I jumped to find the answer to a great question.

About 1.5 million American women enter menopause each year and an estimated 80 percent experience one or more symptoms: vaginal dryness, insomnia, hot flashes, weight gain, loss of bone density and mood swings. "There is research showing the benefit of exercise on most of those things," particularly the last four, said Darlene Kvist, director of Nutritional Weight and Wellness in St. Paul.

The April 2007 issue of the Annals of Behavioral Medicine detailed a study by Penn State kinesiologist Steriani Elavsky, who divided 164 sedentary, 50ish, hot-flashing, insomniac women into groups of walkers, yogis or dedicated couch potatoes for four months.

"We found a significant association between changes in cardiorespiratory fitness and changes in menopausal symptoms," Elavsky reported on Penn State's College of Health and Human Development website. "Women who experienced decreases in menopausal symptoms in the study also experienced improvements in all positive mental health and quality-of-life outcomes."

But of all menopausal symptoms, weight gain may be the biggest downer, say middle-age women who swear they're adding pounds but are not eating more. It's not in your head. Turns out that two key culprits -- changes in ovulation and insulin metabolism -- conspire to pack on unwanted pounds in women's middle years, Kvist said.

"By ovulating, you burn 300 calories more per day. So when women stop ovulating you have to compensate or change your eating [habits], because 65 to 75 percent of women gain weight at menopause involuntarily," Kvist said. "The other thing that happens is that as we age, we get more and more insulin-resistant. Almost everyone does. But as women hit menopause, they really can become more insulin-resistant. And the more insulin-resistant you are, the easier it is for you to gain weight."

To fight back, exercise. With exercise, the body's muscle, fat and liver better respond to insulin, which helps cells take in and metabolize glucose rather than letting it pool in the blood or turn to fat.

While weight gain can be demoralizing, hot flashes really drive many women nuts. In her book, "Complete Guide to Women's Health," Dr. Nieca Goldberg notes that 50 to 85 percent of perimenopausal women repeatedly experience the short, pesky spikes in body temperature over several years. Those sweaty moments are brought to you courtesy of your plunging estrogen levels.

Not only do many women have to change clothes or mop up several times a day, but they also often experience bouts of anxiety, insomnia and even heart palpitations. Bio-identical or synthetic hormone replacement therapies or natural remedies might help.

But Goldberg writes that women who enjoyed the health benefits of exercise also reported a decrease in hot flashes. She notes that while exercise might not get rid of the hot flashes for everyone, exercising women didn't seem to be bothered by them as much. They generally felt better -- and slept better.

"If you eat right [cut caffeine and sweets] and you exercise , menopausal women do sleep better," said Wendy Cates-Dancer, a registered nurse who teaches the course "Hot Flash Solutions for Perimenopause and Menopause" at the Nutritional Weight and Wellness Centers.

"When we talk about exercise in class, we also talk about osteoporosis and that you need to have weight-bearing exercises three times a week" because that builds bone density and combats the bone loss that menopause can bring, she said.

With all the benefits tucked into exercise, many middle-age women would be smart to head to the gym, park, community center or mall to partake in regular aerobic classes, mall walking, biking and weight training.

Dee DePass • 612-673-7725