Effects of resistance training on endothelial function: A systematic review and meta-analysis.
Level 1 - systematic review of randomized trials
Systematic review and meta-analysis of randomized controlled trials
PubMed 34399984 · doi:10.1016/j.atherosclerosis.2021.07.009
What was done
Authors conducted a systematic review and meta-analysis of randomized controlled trials searching seven electronic databases (PubMed, Embase, CINAHL, SPORTDiscus, Scopus, Web of Science, PEDro). Eligible trials evaluated resistance training versus a non-exercise control group or contralateral untrained limb in adults/elderly and measured post-occlusion brachial artery flow-mediated dilation (FMD) with ultrasound pre- and post-intervention. Mean differences (MDs) and 95% confidence intervals (CIs) were pooled using an inverse variance random-effects model.
What was found
Twenty-three studies were included (785 participants; 53% female): - Overall effect: Resistance training significantly increased FMD compared to control (n = 366 training vs 358 control; MD 2.39%, 95% CI 1.65 to 3.14; p < 0.00001). - Modality subgroups: Significant improvements occurred with dynamic resistance training (n = 545; MD 2.12%, 95% CI 1.26 to 2.98; p < 0.00001) and isometric handgrip training (n = 179; MD 3.32%, 95% CI 1.68 to 4.96; p < 0.0001). - Health status subgroups: FMD increased in healthy adults (n = 261; MD 2.11%, 95% CI 1.04 to 3.18; p < 0.0001), cardiovascular disease patients (n = 310; MD 2.89%, 95% CI 0.88 to 4.90; p = 0.005), and metabolic disease patients (n = 153; MD 2.40%, 95% CI 1.59 to 3.21; p < 0.00001).
Why it matters
This meta-analysis establishes that resistance training (both dynamic and isometric handgrip) meaningfully improves peripheral endothelial function across both healthy populations and those with cardiometabolic diseases.
Limits
The total sample size across 23 studies was modest (785 participants, averaging ~34 participants per study). The abstract does not provide details on training intensity, frequency, program duration, statistical heterogeneity, or translation into hard clinical cardiovascular endpoints.
Cited by
- contradicts Resistance training does not produce the same cardiovascular adaptations as aerobic exercise, such as improvements in endothelial function, cardiovascular structure, and blood pressure.