Leisure Time Physical Activity and Mortality | Journal Scan
Is leisure time physical activity associated with reduced mortality?
Data from six population-based prospective studies (from the National Cancer Institute Cohort Consortium) were pooled together. Baseline data from 1992 to 2003 included self-reported physical activity from participants residing in the United States and Europe. The exposure of interest was time spent performing moderate to vigorous leisure time physical activity. The primary outcome of interest was mortality.
A total of 661,137 participants (median age 62 years) were included. A total of 116,686 deaths were recorded over a mean follow-up of 14.2 years. Compared to participants who reported no leisure time physical activity, a 20% low risk for death was observed among participants who exercised, but at less than the recommended minimum of 7.5 metabolic-equivalent hours per week (hazard ratio [HR], 0.80; 95% confidence interval [CI], 0.78-0.82). With increasing doses of physical activity, lower mortality risks were observed. For those with 1-2 times the recommended minimum, a 31% lower mortality risk (HR, 0.69; 95% CI, 0.67-0.70) was observed, and for participants who performed 2-3 times the minimum recommendation, a 37% lower risk was observed (HR, 0.63; 95% CI, 0.62-0.65). A ceiling effect was observed such that beyond 3-5 times the recommended level of physical activity, little additional benefit related to mortality reduction was observed. No evidence of harm was observed with increasing levels of leisure time physical activity. A similar pattern (i.e., reduction in mortality) related to cardiovascular disease or to cancer was observed with increasing dose of leisure time physical activity.
The investigators concluded that moderate or vigorous intensity physical activity was associated with reduced mortality risk in a dose-dependent manner. A threshold effect appeared at approximately 3-5 times the recommended level of leisure time physical activity; however, no excess risk was observed up to 10 times the level of minimal activity.
These data support the recommendations for regular physical activity for most adults, and suggest that increased activity is not harmful.
Keywords: Cardiovascular Diseases, Exercise, Leisure Activities, Metabolic Equivalent, Motor Activity, Neoplasms, Mortality, Risk, Follow-Up Studies, Prospective Studies, Primary Prevention, Self Report
< Back to Listings