AHA Nutrition: A Little Exercise Goes a Long Way for Overweight Older Women

By John Gever
COLORADO SPRINGS, Colo., March 13 -- For overweight postmenopausal women, as little as 10 minutes of exercise daily can improve the quality of life, researchers said here.Feelings about general health, vitality, mental health, and social functioning all increased significantly after six months of exercise, compared with women who did not exercise, reported Timothy Church, M.D., of Pennington Biomedical Research Center in Baton Rouge, La., at the American Heart Association's Conference on Nutrition, Physical Activity and Metabolism."It's commonly said that exercise gives you more energy, exercise makes you feel better, all kinds of things like that," said Dr. Church in an interview. "Interestingly, none of that's ever really been proven."
He and colleagues analyzed data from an earlier randomized study called Dose Response to Exercise in Postmenopausal Women (DREW). It included 464 participants, of whom 430 completed the protocol.
The women were postmenopausal, sedentary at baseline with a mean age of 57 (SD 6.4) and overweight or obese with a mean body mass index of 31.8 (SD 3.8). They were assigned to four exercise groups: none, 4 kcal/kg/week, 8 kcal/kg/week, or 12 kcal/kg/week. These targets correspond to 70, 135, and 190 minutes of exercise per week. The three exercise groups represented 50%, 100% and 150% of the NIH consensus development panel recommended physical activity dose.
Exercise was supervised and involved treadmills and stationary bicycles. The researchers confirmed that adherence to the protocol exceeded 97%.
The DREW study's primary focus was on objective measures of aerobic fitness. Those data were published last year.
But Dr. Church and colleagues also questioned participants about various quality-of-life parameters at baseline and after six months in the study. The researchers used the Medical Outcomes Short Form-36 questionnaire, which has eight components covering mental and physical functioning, each on a 100-point scale.
The high-exercise group showed significant improvement relative to the control group in seven of eight measures, with most P values <0.01. Most measures showed improvements of eight to 12 points in this group.
The low-exercise group improved significantly in one aspect of physical quality of life (general health) and in three of four mental components (overall mental health, social functioning, and vitality) (P<0.05). In this group, improvements of four to eight points were common.
Significant dose-response relationships were found for all components except bodily pain, with P values ranging from 0.044 to <0.001.
All exercise groups lost modest amounts of weight, with mean losses of 1.3 to 1.9 kg.
Dr. Church said there was no significant correlation between weight loss and change in quality of life on any component.
The exercise was well tolerated, with fewer than 10% of the study's original participants failing to complete the study.
Dr. Church noted that the participants had a relatively high quality of life at baseline, which would suggest that there would be less room for subsequent improvement.
Thus, it was especially notable that the results did show significant improvements in many measures, he said.
He said that including only overweight, postmenopausal women was a limitation, "but we would assume that the results wouldn't be different in any other group."
Funding information for the study was not reported.
The authors reported no potential conflicts of interest.
Primary source: AHA Meeting 2008Source reference:Thompson AM, et al "Effect of different doses of physical activity on quality of life in overweight, sedentary, postmenopausal women" AHA Meeting 2008; Abstract 18.