Independent and joint associations between leisure time physical activity and strength activities with mortality outcomes in older adults ≥65 years-of-age: a prospective cohort study.

Scientific evidence regarding the combined effect of both aerobic leisure time physical activity (LTPA) and muscle strengthening activities on all-cause, CVD or cancer mortality in older adults is scant. The aim of the study was to investigate the associations between recommended physical activity and mortality in older adults ≥65 years-of-age. This prospective cohort study used data from the National Health Interview Surveys from 1997-2013 linked with mortality files through December 31, 2015 (n=89,962). The main outcomes included all-cause, cardiovascular disease (CVD) and cancer mortality. The main exposure variables were aerobic leisure time physical activity and guideline-concordant strength training during leisure time. Cox regression models were used to calculate the hazard ratios (HR) and the corresponding 95% confidence intervals (CI). Muscle-strengthening activity at least twice per week were associated with lower hazards of all-cause mortality (HR 0.92; 95% CI 0.88-0.96), CVD mortality (HR 0.90; 95% CI 0.81-0.99) and cancer mortality (HR 0.87; 95% CI 0.79-0.96). Those who reached the recommended weekly amount of LTPA, had lower hazard of all-cause mortality by 35% (HR 0.66; 95% CI 0.63-0.67), the hazard of CVD 38% (HR 0.62; 95% CI 0.58-0.67), and cancer mortality by 22% (HR 0.78; 95% CI 0.73-0.84). The hazard of death among those who were physically active in both leisure time and engaged in muscle-strengthening activities were 0.57 (95% CI 0.54-0.60) for all-cause mortality, 0.53 (95% CI 0.47-0.61) for CVD mortality, and 0.66 (95% CI 0.58-0.75) for cancer mortality. Thus, engaging in muscle-strengthening activity ≥2 times/week may provide additional benefits among physically active older adults.