Adults with diabetes face elevated mortality risk and accelerated loss of muscle mass and strength. The study aimed to evaluate associations of muscle-strengthening activity (MSA) with all-cause, cardiovascular disease (CVD), and cancer mortality in US adults with diabetes, both independent of and jointly with moderate-to-vigorous aerobic physical activity (MVPA).
This was a prospective cohort analysis of 29,609 adults with diabetes drawn from the US National Health Interview Survey (baseline years 1997–2018). Participants were free of CVD and cancer at baseline. Mortality ascertainment extended through 2019 via linkage to the National Death Index.
MSA and MVPA were assessed using standardized self-report questionnaires administered in the survey. MSA was categorized by frequency (no MSA, <1 time/week, 1 time/week, 2 times/week, 3 times/week, 4–6 times/week, and ≥7 times/week). MVPA was categorized relative to guideline levels (notably a 150 min/week threshold).
Over a total of 270,178 person-years of follow-up, the cohort experienced 6,716 all-cause deaths, 1,995 deaths attributed to cardiovascular disease, and 1,202 cancer deaths. Mean baseline age of the cohort was 55.7 years, and 51.6% of participants were female.
Cox proportional hazards models were used to estimate adjusted hazard ratios (aHRs) for mortality by MSA categories and jointly by MSA and MVPA categories. The models produced point estimates and 95% confidence intervals for associations between activity exposures and mortality endpoints. The authors evaluated non-linearity of associations and effect modification by age and sex.
A U-shaped association between MSA frequency and all-cause mortality was observed. Compared with no MSA, adjusted hazard ratios for all-cause mortality were reported as follows:
These estimates indicate mortality benefits associated with MSA up to three times per week, with attenuation of benefit at higher reported frequencies. Non-linear associations were also identified for CVD and cancer mortality, though specific point estimates for each MSA category and these endpoints were reported in the source and summarized here as demonstrating non-linearity rather than monotonic dose–response.
When MSA was considered jointly with aerobic MVPA, the lowest risks of all-cause and CVD mortality were observed among adults performing MSA ≤ 2 times/week combined with MVPA ≥ 150 min/week, compared with the reference group of no MSA and MVPA < 150 min/week. This suggests an additive or synergistic association when modest MSA is combined with guideline-level aerobic activity.
The reported associations between MSA and mortality did not vary meaningfully by age or sex according to the authors. In other words, the U-shaped and non-linear patterns were consistent across age and sex strata in this cohort.
In this large, nationally representative sample of US adults with diabetes, engaging in muscle-strengthening activity up to three times weekly was associated with lower all-cause, CVD, and cancer mortality, independent of aerobic MVPA. The findings support incorporation of MSA into management plans for adults with diabetes, and they highlight that combining modest MSA (≤ 2 times/week) with guideline-recommended aerobic MVPA (≥ 150 min/week) may confer the greatest reduction in all-cause and cardiovascular mortality risk.
Clinicians may consider counseling patients with diabetes about the potential long-term mortality associations of both resistance-style training and aerobic exercise, emphasizing achievable MSA frequencies and meeting aerobic activity guidelines.
Key limitations inherent to the source include reliance on self-reported physical activity measures and observational study design, which precludes causal inference. The abstract reports that associations were adjusted (aHRs presented), but specific covariates and modeling details are contained in the full article. The source states that there were no declared conflicts of interest.
Overall, the study provides population-level evidence that modest muscle-strengthening activity, especially when combined with recommended aerobic MVPA, is associated with lower mortality risk among adults with diabetes.