Even Small Amounts of Exercise Are Beneficial

The above headline comes from the May 17, 2007 issue of Medscape and is the result of a study published in the May 16, 2007 issue of the Journal of the American Medical Association (JAMA). This study showed that much smaller amounts of exercise than previously believed can help heart health. The research showed that as little as 75 minutes of exercise per week can improve cardiorespiratory fitness levels of sedentary overweight individuals. This level of exercise is lower than that currently recommended to produce weight loss.

This study was conducted with 464 postmenopausal women who were overweight or obese and had raised blood pressure. These women were divided into four groups. Three of the groups represented 50% then 100% and then 150% of the recommended exercise levels currently believed needed to lose weight, and the remaining group was a sedentary group used as a control group for comparison.

The results showed that even a modest amount of exercise showed health benefits. The authors noted that there was little or no weight loss in the low exercise group, but there was a reduction in waist circumference which they noted was more significant. They stated, "Perhaps the most striking finding of our study is that even activity at the 4-kcal/kg per week level (approximately 72 min/wk) was associated with a significant improvement in fitness compared with women in the non-exercise control group." They later added, "Data presented in our study show that even 72 minutes of moderate-intensity physical activity per week accumulated over about 3 days has a significant effect on fitness in previously sedentary postmenopausal women. This information can be used to support future recommendations and should be encouraging to sedentary adults who find it difficult to find the time for 150 minutes of activity per week, let alone 60 minutes per day."

In an accompanying editorial in the same issue of JAMA, I-Min Lee, MBBS, ScD, from Brigham and Women's Hospital in Boston, Massachusetts, concluded, "Although current knowledge regarding the dose-response relation between physical activity and health remains incomplete, the study by Church et al does provide important information on the dose of physical activity to improve physical fitness, a strong predictor of chronic disease and premature mortality. This may be succinctly summarized for patients and clinicians as 'Even a little is good; more may be better!"