and also face a lower risk of becoming depressed, according to a report in the August 15th issue of the American Journal of Epidemiology.

Dr. William J. Strawbridge of the Public Health Institute, Berkeley, California, and colleagues studied 1,947 people participating in the Alameda County Study. All were between 50 and 94 years old at the beginning of the study, and were followed for 5 years. The investigators examined the effects of physical activity on depression, with and without excluding disabled patients. They used an 8-point scale to rate study participants' physical activity level.

Every 1-point increase in physical activity protected against both prevalent depression and incident depression over 5 years after adjusting for age, sex, ethnicity, financial strain, chronic conditions, disability, body mass index, alcohol consumption, smoking and social relations. Each point cut the risk of being depressed by 10%, and of becoming depressed by 17%. "Regular physical activity, such as walking, exercising, swimming or playing active sports for older adults will reduce the risk of subsequent depression," Strawbridge told Reuters Health in an interview. "This benefit is similar for those with and without physical disabilities."

And, Strawbridge added, "The most common form of physical activity for members of the Alameda County Study is taking long walks, which shows that physical activity does not have to involve elaborate equipment."

The investigators note that "it is plausible that persons with high levels of physical activity are also more likely to engage in other beneficial health behaviors such as not smoking, avoiding obesity, and not drinking to excess."