Resistance Training, Aerobic Activity, Television Viewing, and Risk of Major Cardiovascular Events in U.S. Women.

BACKGROUND

Long-term resistance training may influence cardiovascular health, but evidence in women, particularly in the context of aerobic activity and sedentary behavior, remains limited.

OBJECTIVES

This study sought to examine the association between long-term resistance training and risk of major cardiovascular disease (CVD) in women, and to evaluate joint associations with aerobic activity, sedentary television viewing, and key training-related characteristics.

METHODS

We conducted a prospective cohort study among 117,025 women from the Nurses' Health Study (N = 45,669; 2002-2020) and Nurses' Health Study II (N = 71,356; 2003-2017), with up to 5 repeated assessments of physical activity. Resistance training was reported every 4 years, and time-varying cumulative averages were calculated to represent long-term exposure. The primary outcome was incident major CVD, defined as nonfatal or fatal myocardial infarction (MI), stroke, coronary artery bypass grafting, or percutaneous coronary intervention.

RESULTS

Over a mean of 14.5 years of follow-up (1,630,964 person-years), 5,459 incident major CVD events occurred. Compared with no resistance training, women performing ≥2 h/wk had a 20% lower risk of major CVD (HR: 0.80; 95% CI: 0.69-0.92; P for trend = 0.007), and each additional 1 h/wk was associated with a 5% lower risk (HR per 1 h/wk: 0.95; 95% CI: 0.92-0.99). The inverse association was stronger for MI (HR for ≥2 h/wk vs none: 0.56; 95% CI: 0.41-0.76) but not evident for stroke (HR: 0.99; 95% CI: 0.80-1.23). Women who met recommendations for aerobic activity (≥15 metabolic equivalent of task hours per week), resistance training (≥1 h/wk), and low sedentary television viewing (<2 h/d) had a lower risk of major CVD (HR: 0.60; 95% CI: 0.53-0.69), than those meeting aerobic and low sedentary television viewing recommendations but not resistance training (HR: 0.73; 95% CI: 0.67-0.80). Greater consistency in maintaining resistance training (≥75% of follow-up) and engaging in both upper and lower limb training were associated with stronger inverse associations.

CONCLUSIONS

In this large prospective study of U.S. women, consistent resistance training, especially when integrated with recommended levels of aerobic activity and reduced sedentary television viewing, was associated with a substantially lower risk of major CVD, particularly MI.