Long-term resistance training with all-cause and cause-specific mortality: assessing dose-response and joint associations with aerobic physical activity

OBJECTIVE: To examine whether resistance training is associated with lower all-cause and cause-specific mortality, the dose-response relationship, and joint effects with aerobic activity. METHODS: We included participants from three large prospective cohorts (Health Professionals Follow-up Study, 1992-2022; Nurses' Health Study, 2002-2021; Nurses' Health Study II, 2003-2021). Weekly resistance training duration and aerobic exercise duration were assessed using validated questionnaires at baseline and biennially thereafter. Cox proportional hazard models were used to estimate hazard ratios (HR) and 95% confidence intervals (95% CI). RESULTS: Among 147 374 participants (31 540 men and 115 834 women) followed for up to 30 years, we documented 35 798 deaths. Compared with no resistance training, 90-119 min/week of resistance training was associated with a 13% lower risk of all-cause mortality (HR 0.87, 95% CI 0.81 to 0.95), 19% lower risk of cardiovascular mortality (HR 0.81, 95% CI 0.67 to 0.97) and 27% lower risk of neurological disease mortality (HR 0.73, 95% CI 0.58 to 0.92), adjusting for aerobic activity. No additional benefit was observed above 120 min/week. Reduced cancer mortality risk was seen only at lower levels of resistance training: HR 0.91 (95% CI 0.86 to 0.97) for 1-29 min/week and HR 0.88 (95% CI 0.81 to 0.97) for 30-59 min/week. In joint analyses, compared with those with inadequate aerobic activity (<7.5 metabolic equivalent of task (MET)-hours/week) and no resistance training, mortality risk was lowest among participants with both high aerobic and resistance training (eg, HR 0.55 (95% CI 0.50 to 0.60) for 30 to <45 MET-hours/week of aerobic and 60-119 min/week of resistance training), as well as among those attaining ≥45 MET-hours/week of aerobic activity regardless of resistance training level (HRs from 0.53 to 0.58). CONCLUSION: Using repeated measures of resistance training over up to 30 years of follow-up, moderate long-term resistance training was associated with lower all-cause mortality, with lowest risks plateauing at around ≥120 min/week of resistance training. Resistance training was associated with further reduced mortality risk at all levels of aerobic activity up to around ≥45 MET-hours/week of aerobic activity.