Precompetitive and recreational gymnasts have greater bone density, mass, and estimated strength at the distal radius in young childhood

Young recreational and precompetitive gymnasts had, on average, 23% greater bone strength at the wrist compared to children participating in other recreational sports. Recreational gymnastics involves learning basic movement patterns and general skill development and as such can easily be implemented into school physical education programs potentially impacting skeletal health. Competitive gymnasts have greater bone mass, density, and estimated strength. The purpose of this study was to investigate whether the differences reported in the skeleton of competitive gymnasts are also apparent in young recreational and precompetitive gymnasts. One hundred twenty children (29 gymnasts, 46 ex-gymnasts, and 45 non-gymnasts) between 4 and 9 years of age (mean = 6.8 +/- 1.3) were measured. Bone mass, density, structure, and estimated strength were determined using peripheral quantitative computed tomography at the distal (4%) and shaft (65%, 66%) sites in the radius and tibia. Total body, hip, and spine bone mineral content (BMC) was assessed using dual energy X-ray absorptiometry. Analysis of covariance (covariates of sex, age and height) was used to investigate differences in total bone content (ToC), total bone density (ToD), total bone area (ToA), and estimated strength (BSI) at the distal sites and ToA, cortical content (CoC), cortical density (CoD), cortical area (CoA), cortical thickness, medullary area, and estimated strength (SSIp) at the shaft sites. Gymnasts and ex-gymnasts had 5% greater adjusted total body BMC and 6-25% greater adjusted ToC, ToD, and BSI at the distal radius compared to non-gymnasts (p < 0.05). Ex-gymnasts had 7-11% greater CoC and CoA at the radial shaft and 5-8% greater CoC and SSIp at the tibial shaft than gymnasts and non-gymnasts. Ex-gymnasts also had 12-22% greater ToC and BSI at the distal tibia compared to non-gymnasts (p < 0.05). This data suggests that recreational and precompetitive gymnastics participation is associated with greater bone strength.