NEW YORK (Reuters Health) – While any type of exercise can do a body good, people who want to reshape their figures may need to boost the intensity of their workouts, a small study suggests.
The study, which followed 27 middle-aged obese women, found that those who exercised at a high intensity for four months successfully shed fat from their midsections. Women who exercised at a low intensity, however, showed no such changes in body fat.
The findings suggest that for people who want to change their body composition, the intensity of the exercise is matters, researchers report in the journal Medicine & Science in Sports & Exercise.
The real goal of losing fat around the middle, however, is not to fit into a smaller pair of jeans, according to senior researcher Dr. Arthur Weltman, of the University of Virginia in Charlottesville.
Excess abdominal fat contributes to high blood pressure, diabetes and heart disease, and losing it can help cut these health risks.
“Improving body composition can improve overall health and quality of life, and exercise-induced reductions in total and visceral abdominal fat can significantly lower the risk of chronic disease,” Weltman said in a statement issued by the journal.
“For obese women entering the middle and later stages of life,” he explained, “reducing internal abdominal fat or preventing too much of it forming is crucial. Exercise, especially vigorous exercise, may be the best way to do it.”
The findings are based on 27 obese women who were randomly assigned to one of three groups: one that remained sedentary; one that started exercising at a low intensity — walking at a pace that brought them to 50 percent to 60 percent of their maximum aerobic capacity; and a third that varied the intensity of their workouts — walking or jogging more vigorously on some days of the week.
After 16 weeks, women in both exercise groups had improved their cardiovascular fitness and those in the lower-intensity group showed a significant reduction in blood pressure.
However, only the higher-intensity group showed changes in body composition, whittling more than 2 inches from their waistlines, on average. CT scans showed that they had also lost visceral fat — deep abdominal fat that surrounds the organs and is thought to be particularly unhealthy.
The good news for the average exerciser is that high-intensity exercise need not be an Olympic workout, according to Weltman. In this study, he and his colleagues prescribed each woman’s exercise routine based on her individual capabilities.
Basically, Weltman told Reuters Health, low-intensity meant that the women perceived the workout as fairly easy, whereas they judged the high-intensity workout as hard.
He recommended that anyone new to exercise start off slow and gradually build the intensity, duration and frequency of workouts.
Experts also generally recommend that older adults and people with chronic health conditions talk to their doctors before becoming active.
While the current study included only middle-aged women, Weltman noted that, based on other research, the findings are likely relevant to other exercisers as well. “We have no reason to believe that we wouldn’t see similar results in other groups,” the researcher said.
SOURCE: Medicine & Science in Sports & Exercise, online October 21, 2008.