The benefits associated with being physically active include higher levels of fitness and lower risks of developing a number of chronic diseases.  In terms of weight management, however, most people who lose weight from increased physical activity are not able to sustain the loss over time.

A 2010 study by researchers from the Harvard Medical School, Harvard School of Public Health and the Boston Veterans Affairs Healthcare System, published in the Journal of the American Medical Association, “Physical Activity and Weight Gain Prevention,” seeks to examine the relationship between different amounts of physical activity with weight changes. The sample used in this study was a large cohort of middle-aged and older women over a period of 13 years.

The study’s key findings are:

• On average, subjects gained 2.6 kg over the 13 years of the study.
• Those who averaged 60 minutes a day of moderate-intensity physical activity gained less weight than those who were less active.
• Women with a body mass index of 25 or lower exhibited significant weight loss from physical activity.
• Subjects with a BMI over 25 did not exhibit significant weight loss from physical activity.

Because the study indicated that women with BMIs over 25 had fewer weight-loss benefits from physical activity, researchers suggested that measures to prevent weight gain should be emphasized. In addition, they recommended following the U.S. Department of Health and Human Services’ physical activity guidelines for Americans, which suggest that 150 minutes of exercise per week can help individuals reap significant health benefits.

Tags: aging, exercise, obesity