Background:

Little is known about the effects of physical activity on weight loss in older adults.

Methods:

Participants included 4512 community-dwelling older (≥65 yr) men and women from the Cardiovascular Health Study. Physical activity (PA) was determined from a questionnaire at baseline and subjects were divided into sex-specific PA quartiles. Weight was measured at baseline and annually over the 8 years of follow-up. The influence of PA on longitudinal changes in body weight was examined using mixed models while adjusting for lifestyle variables, sociodemographic characteristics, and disease status.

Results:

Body weight declined in a curvilinear manner over time with accelerated weight loss occurring in the final years. Over the 8 yr follow-up period, the least active PA quartile lost 2.72 kg. Weight loss was attenuated by 0.55 kg (20%, P = .057), 0.80 kg (29%, P = .05), and 0.69 kg (25%, P = .016) within the second through fourth PA quartiles. The effects of PA did not differ by gender, but increased with advancing age.

Conclusion:

Participation in modest amounts of PA attenuated age-related weight loss by approximately 25% with little additional benefit observed at higher PA levels. This finding adds to the growing number of health outcomes that are positively affected by PA.