Can exercise snacks alleviate musculoskeletal discomfort in prolonged sitting? A systematic review of randomized controlled trials

BACKGROUND: Sedentary behavior constitutes a significant global public health issue and is strongly associated with musculoskeletal disorders, particularly neck and back pain. Exercise snacks, characterized by brief bouts of fragmented physical activity, provide a feasible intervention to interrupt prolonged sitting within occupational contexts. However, their efficacy in alleviating musculoskeletal discomfort has not been systematically evaluated. This systematic review aimed to evaluate the efficacy of exercise snacks in reducing musculoskeletal discomfort in sedentary populations. METHODS: A systematic search was conducted in Web of Science, PubMed, Scopus, Cochrane, EMBASE, and MEDLINE up to November 1, 2025, in accordance with PRISMA guidelines. Randomized controlled trials (RCTs) involving adults (aged ≥ 18 years) in sedentary occupations were included. Eligible studies compared interventions that interrupted prolonged sitting with exercise snacks against a control condition of uninterrupted sitting or passive rest. The primary outcome was musculoskeletal discomfort, and the risk of bias was assessed using the Cochrane Risk of Bias 2.0 tool. RESULTS: Six RCTs involving 210 participants were included in the review. Interventions varied in modality (stretching, walking, stair climbing, dynamic contractions) and duration (2 to 10 min). Four studies demonstrated that exercise snacks significantly alleviated musculoskeletal discomfort compared to prolonged sitting or passive rest. Interventions incorporating targeted muscle stretching, strengthening, or moderate-intensity activities (e.g., stair climbing) demonstrated superior efficacy compared to low-intensity walking or passive controls. However, heterogeneity in study design was observed, and notably, five of the six studies were assessed as having a high risk of bias, limiting the strength of these findings. CONCLUSIONS: Overall, interrupting prolonged sitting with exercise snacks may represent a feasible strategy to alleviate musculoskeletal discomfort in sedentary populations. Exercise snacks appear superior to passive rest; however, due to the substantial heterogeneity and high risk of bias across the majority of included studies, these findings should be interpreted with caution. Future high-quality, long-term RCTs in real-world settings are warranted to establish robust guidelines.