Impact of Resistance Training on Body Composition and Physical Function in Individuals with Down Syndrome: A Meta-Analysis

Objectives: Down syndrome (DS) is associated with challenges like increased fat mass and reduced muscle tone. This study aims to analyze the impact of resistance training on improving muscle strength and physical function in individuals with DS. Methods: We conducted a comprehensive search of PubMed, Scopus, Google Scholar, Cochrane Library, and China National Knowledge Infrastructure for studies published up to August 2023. Standardized mean differences and 95% confidence intervals were used to evaluate the efficacy of resistance training. Results: Eight randomized controlled trials (RCTs), including 127 participants with DS, met the inclusion criteria. Resistance training significantly improved muscle strength in the knee extensors (SMD: 1.009, 95% CI: 0.505-1.513), knee flexors (SMD: 1.133, 95% CI: 0.106 to 2.16), and upper limbs (SMD: 0.748, 95% CI: 0.152-1.343). The SMD for upper limb function was 0.385 (95% CI: 0.004-0.765), showing a small improvement. For walking ability, the SMD was 0.259 (95% CI: -0.171-0.690), and for stair climbing ability, the SMD was 0.257 (95% CI: -0.189-0.703), both indicating no significant changes. Improvements in upper limb physical function were significant, but no notable improvements were seen in lower limb functions. Conclusions: Resistance training for more than four weeks enhances muscle strength in individuals with DS, with greater gains seen in younger participants. While improvements were noted in upper limb physical function, lower limb function remained largely unchanged. These findings suggest that resistance training is a valuable exercise for improving muscle strength and physical function in individuals with DS.