Higher premenarcheal bone mass in elite gymnasts is maintained into young adulthood after long-term retirement from sport: A 14-year follow-up

Abstract

Sports that impact-load the skeleton during childhood and adolescence increase determinants of bone strength such as bone mineral content and density; however, it is unclear if this benefit is maintained after retirement from the sport. The purpose of this study was to assess whether the previously reported higher bone mass in a group of premenarcheal gymnasts was still apparent 10 years after the cessation of participation and withdrawal of the gymnastics loading stimulus. In 1995, 30 gymnasts 8 to 15 years of age were measured and compared with 30 age-matched nongymnasts. Twenty-five former gymnasts and 22 nongymnasts were measured again 14 years later (2009 to 2010). Gymnasts had been retired from gymnastics training and competition for an average of 10 years. Total body (TB), lumbar spine (LS), and femoral neck (FN) bone mineral content (BMC) was assessed at both measurement occasions by dual-energy X-ray absorptiometry (DXA). Multivariate analysis of covariance (MANCOVA) was used to compare former gymnasts' and nongymnasts' BMC while controlling for differences in body size and maturation (covariates: age, height, weight, and years from menarche [1995] or age at menarche [2009 to 2010]). Premenarcheal gymnasts (measured in 1995) had significantly greater size-adjusted TB, LS, and FN BMC ( p < 0.05) (15%, 17%, and 12%, respectively) than nongymnasts. Ten years after retirement, gymnasts had maintained similar size-adjusted TB, LS, and FN BMC differences ( p < 0.05) (13%, 19%, and 13%, respectively) when compared with nongymnasts. Bone mass benefits in premenarcheal gymnasts were still apparent even after long-term (10 years) removal of the gymnastics loading stimulus. ß

Physical activity when young provides lifelong benefits to cortical bone size and strength in men

“…3B). Continuing throwers (0.92 cm 4 , 95% CI, 0.62-1.24 cm 4 , P < 0.001) normalized to controls maintained 50% of the throwingrelated benefit in torsional strength observed in active throwers (1.83 cm 4 . 95% CI, 1.34-2.32 cm 4 , P < 0.001), whereas former throwers maintained 38% of that benefit (0.69 cm 4 ; 95% CI, 0.42-0.96 cm 4 , P < 0.001).…”

“…2 A and E). The persistent benefit of throwing on size contributed to maintenance of the throwing-derived benefit in bone strength, with former throwers in the 50+ y detraining group (0.62 mm 4 ; 95% CI = 0.33-0.91 mm 4 , P < 0.001) still having more than one-third (33.7%) of the benefit in torsional strength observed in active throwers (1.83 mm 4 ; 95% CI = 1.34-2.32 mm 4 , P < 0.001) (Fig. 2I).…”

“…A popular hypothesis is that physical activity increases peak bone mass to prime the skeleton against the bone loss occurring during aging (3). Prospective observational studies suggest some of the benefits in bone mass generated through physical activity during youth persist into early adulthood (4)(5)(6)(7)(8)(9); however, the prospective assessment of lifelong benefits is not practically feasible. Instead, the lifelong skeletal benefits of physical activity during youth can be explored using cross-sectional studies comparing former athletes with controls.…”

Specific Bone Mass Acquisition in Elite Female Athletes

“…This was confirmed in our study by the maintenance of aBMD gain in the late pubertal stages compared with the other 2 groups. Another element in favor of higher peak bone mass in gymnasts is the systematically higher bone mass in retired gymnasts compared with controls (16,47,48).…”

Exercise characteristics influence femoral cross-sectional geometry: a magnetic resonance imaging study in elite female athletes

“…However, while some studies have reported that retired athletes have higher BMD or BMC than age-matched controls [7,8], the results of other studies suggest that the bone mass gained through exercise is gradually lost after retirement from competition or cessation of training [9,10]. In addition, bone strength can increase without changes in bone mass [11].…”