Strength Training More Cardioprotective than Aerobic Activity throughout Adulthood in Americans

Background: Cardioprotective benefits of physical activity are known, but research and recommendations often focus on aerobic activity rather than resistance training. Effects of resistance training thus may be missed. We compare their population-level associations with risks for cardiovascular disease (CVD).

Methods: In 4086 non-pregnant Americans from NHANES, CVD risks (hypertension, overweight, diabetes, dyslipidemia) were modelled as binary functions of resistance and/or aerobic activity, corrected for age, ethnicity, gender and smoking and stratified by age (21-44 or 45+). Initial models classified each activity type as either ‘none’ or quartile of those with any; subsequent models were collapsed into ‘none’ vs ‘any.’

Results: Thirty-six and 28% of younger, and 25 and 21% of older, subjects engaged in resistance and aerobic activity. Both age groups averaged about 0.5 sessions/day and 20 minutes/day respectively. Resistance and aerobic activity were both associated with lower CVD risk, with flat dose-response curves across low and high activity levels. Associations were strongest for resistance; almost independent of each other; and not explicable by activity-limiting illness.

In youth, both resistance and aerobic activity were associated at p=0.05 with overweight (ORs 0.61 and 0.64) but not hypertension or dyslipidemia. Resistance activity was also associated with diabetes (OR 0.33, p=0.005.)

In older adults both resistance and aerobic activity were associated at p=0.05 with overweight (ORs 0.61 and 0.75) but not dyslipidemia. Resistance activity was also associated with diabetes (OR 0.65) and nonsignificantly with hypertension (OR 0.79, p=0.09.)

Associations between each activity type and overweight were similar after correction for the other type; however only resistance training remained statistically significant.

Conclusions: Clinically relevant cardioprotection was observed from low doses of physical activity, especially resistance but also aerobic, when both activity types were modeled similarly. Research should separate the two activity types, and recommendations should include at least small doses of both.