Exercise Effects on the Reduction of Low-Traumatic and Major Osteoporotic Fractures in Adults. Systematic Review and Meta-Analysis

The aim of the present systematic review and meta-analysis was to determine the effects of exercise on low-trauma overall and major osteoporotic fractures in adults. Our systematic search of six literature databases according to the PRISMA guideline was conducted up to May 22, 2021, and included controlled clinical exercise trials with (a) individuals >= 45 years, (b) cohorts without therapies/diseases related to bone metabolism or falls, (c) an intervention of >= 3 months, and (d) the number of low-traumatic fractures listed separately for the exercise (EG) and control (CG) groups. The study was registered in PROSPERO (ID: CRD42021250467). We applied a mixed-effects conditional Poisson regression model for the analysis. A total of 20 intervention studies with 21 EGs and 20 CGs were included in the analysis. The studies comprising a pooled number of participant-years of n=11,836 in the EG and n=11,275 in the CG. The meta-analysis determined significant effects of exercise on low-trauma overall fracture incidence (rate) ratio (IR: 0.67, 95% confidence interval (95%-CI): 0.51-0.87) and major osteoporotic fractures IR (0.69, 95%-CI: 0.52-0.92). Heterogeneity between the trials was moderate for low-trauma overall (I (2) =40%), and negligible (I (2) <1%) for major osteoporotic fractures. Funnel plots suggest low to moderate evidence of publication/small-study bias in study outcomes for low-trauma overall fractures. Despite some biometric limitations the present study provides further evidence of the positive effect of exercise on low-trauma overall and major osteoporotic fractures in community dwelling middle aged to older adults. With respect to low-trauma overall and major osteoporotic fractures reduction, the study results are comparable to current pharmaceutical agents.