Muscle-strengthening activities are associated with lower risk and mortality in major non-communicable diseases: a systematic review and meta-analysis of cohort studies

Abstract

Objective: To quantify the associations between muscle-strengthening activities and the risk of non-communicable diseases and mortality in adults independent of aerobic activities.

Design: Systematic review and meta-analysis of prospective cohort studies.

Data sources: MEDLINE and Embase were searched from inception to June 2021 and the reference lists of all related articles were reviewed.

Eligibility criteria for selecting studies: Prospective cohort studies that examined the association between muscle-strengthening activities and health outcomes in adults aged ≥18 years without severe health conditions.

Results: Sixteen studies met the eligibility criteria. Muscle-strengthening activities were associated with a 10-17% lower risk of all-cause mortality, cardiovascular disease (CVD), total cancer, diabetes and lung cancer. No association was found between muscle-strengthening activities and the risk of some site-specific cancers (colon, kidney, bladder and pancreatic cancers). J-shaped associations with the maximum risk reduction (approximately 10-20%) at approximately 30-60 min/week of muscle-strengthening activities were found for all-cause mortality, CVD and total cancer, whereas an L-shaped association showing a large risk reduction at up to 60 min/week of muscle-strengthening activities was observed for diabetes. Combined muscle-strengthening and aerobic activities (versus none) were associated with a lower risk of all-cause, CVD and total cancer mortality.

Conclusion: Muscle-strengthening activities were inversely associated with the risk of all-cause mortality and major non-communicable diseases including CVD, total cancer, diabetes and lung cancer; however, the influence of a higher volume of muscle-strengthening activities on all-cause mortality, CVD and total cancer is unclear when considering the observed J-shaped associations.

Systematic review registration: PROSPERO CRD42020219808.

Keywords: cardiovascular diseases; cohort studies; meta-analysis; survival; weight lifting.

Figure 1

Flowchart of the selection of studies included in the meta-analysis.

Figure 2

Two-group meta-analysis of the associations between no versus any muscle-strengthening activities and all-cause mortality, cardiovascular disease (CVD), total cancer and diabetes. RR, relative risk.

Figure 3

Linear dose–response meta-analysis of the associations between muscle-strengthening activities (per 10 min/week increase) and all-cause mortality, cardiovascular disease (CVD), total cancer and diabetes. RR, relative risk.

Figure 4

Non-linear dose–response meta-analysis of the associations between muscle-strengthening activities and all-cause mortality, cardiovascular disease (CVD), total cancer and diabetes. Muscle-strengthening activities were modelled with restricted cubic splines in a random-effects dose–response model. The black line indicates the spline model and dashed lines represent 95% confidence intervals. RR, relative risk.

Figure 5

Meta-analysis of the joint associations of muscle-strengthening and aerobic activities with all-cause mortality, cardiovascular disease (CVD) mortality, total cancer mortality and colon cancer incidence. The definitions of groups for muscle-strengthening and aerobic activities were based on the categories described in online supplemental table 6. RR, relative risk.