Associations Between Resistance Training and All-Cause Mortality: NHANES 1999-2006

Background: The Physical Activity Guidelines 2nd Edition recommends >= 2 days of resistance training (RT). Evidence supports a dose-response relation between RT volume and cardiometabolic health. We examined whether RT guidelines and volume were associated with lower all-cause mortality. Methods: Participants from the 1999-2006 NHANES cycles (N = 5855) self-reported the past 30 days of physical activity including the number of sessions, average session duration in minutes, and activity type. Mortality was ascertained from the linked National Death Index through the end of 2019. Cox proportional hazards regression was used to estimate hazard ratios for all-cause mortality by RT Guideline adherence and per 1000 MET-minutes of monthly RT volume. Results: Approximately 1-in-10 participants met the RT Guidelines (n = 612, 11.6%). The mean monthly RT volume was 2033.3 +/- 2487.7 MET-minutes. Mortality incidence was 10.6% (n = 886). Neither meeting the Guidelines (HR [95% CI]; 1.02 [.74, 1.41], compared to not meeting the Guidelines) nor monthly RT volume per 1000 MET-minutes (1.02 [.92, 1.14]) was associated with all-cause mortality in adjusted models, with no evidence of effect modification by sex or age. Conclusions: The present study did not find an association between RT and all-cause mortality. These results do not support the RT canon, warranting further investigation.