The Effect of Swimming During Childhood and Adolescence on Bone Mineral Density: A Systematic Review and Meta-Analysis.
Level 3 - non-randomized controlled study
Systematic review of non-randomized observational/cohort studies
PubMed 26607734 · doi:10.1007/s40279-015-0427-3
What was done
A systematic review and meta-analysis was conducted using PubMed, SPORTDiscus, and ClinicalTrials.gov searches up to March 2015 following PRISMA guidelines. The review evaluated the effect of systematic swimming training during childhood and adolescence on bone mineral density (BMD). Two separate meta-analyses were performed: swimmers compared to sedentary controls, and swimmers compared to athletes participating in highly osteogenic, high-impact sports.
What was found
Fourteen studies were included in the meta-analyses. The abstract reports no numerical effect sizes or confidence intervals. Swimmers had BMD values similar to sedentary controls and lower than athletes performing high-impact sports. Femoral neck and lumbar spine BMD differences between swimmers and sedentary controls, as well as between swimmers and osteogenic sport athletes, appeared to widen with age in favor of the non-swimming groups. No sex differences were observed.
Why it matters
Swimming provides insufficient mechanical impact to stimulate pediatric bone accrual above sedentary baseline levels. Youth swimmers may need adjunctive weight-bearing or high-impact exercises to optimize peak bone mass accrual.
Limits
The abstract reports no numerical data, effect sizes, or participant sample sizes. The underlying studies are observational comparisons of sports participants rather than randomized trials, leaving potential confounding by nutrition, maturation, and training intensity.
Cited by
- supports Non-weight-bearing exercises such as cycling, swimming, and elliptical training do not produce substantial osteogenic effects on bone mineral density compared to weight-bearing exercise.