daly-effectsofhighimpact-1999.pdf (390.13 kB)
Download fileEffects of high-impact exercise on ultrasonic and biochemical indices of skeletal status: a prospective study in young male gymnasts
journal contribution
posted on 1999-07-01, 00:00 authored by Robin DalyRobin Daly, P A Rich, R Klein, S BassPhysical activity has been proposed as one strategy to enhance bone mineral acquisition during growth. The aim of this study was to determine whether frequent impact loading associated with gymnastics training confers a skeletal benefit on pre- and peripubertal male gymnasts. We measured broadband ultrasonic attenuation (BUA, dB/MHz) at the calcaneus (CBUA); ultrasound velocity (m/s) at the calcaneus (CVOS), distal radius (RVOS) and phalanx (PVOS); serum osteocalcin (OC); total alkaline phosphatase (ALP) and insulin-like growth factor-I (IGF-I) every 3-4 months over an 18-month period in elite male gymnasts and matched normoactive controls (pubertal stage =2). Ground reaction forces of common gymnastics maneuvers were determined using a force platform and loading histories of the upper and lower extremities approximated from video recordings. Ultrasound results were expressed as a standardized score (Z score) adjusted for age, height, and weight. At baseline, no differences were detected between the gymnasts (n = 31) and controls (n = 50) for CBUA, although ultrasound velocity at each site was higher in the gymnasts (0.6-1.5 SD) than the predicted mean in controls (p = 0. 001). Over 18 months, CBUA Z scores increased significantly in the gymnasts from baseline (0.3 vs. 1.0, p < 0.05, n = 18). In contrast, ultrasound velocity did not increase in either group, although CVOS and RVOS remained significantly higher in gymnasts compared with controls (range p < 0.01 and < 0.001). No differences between groups were found for OC, ALP, or IGF-I at any time. Gymnastics training was associated with on average 102 and 217 impacts per session on the upper and lower extremities, respectively, with peak magnitudes of 3.6 and 10.4 times body weight. These results suggest that frequent high-impact, weight-bearing exercise during the pre and peripubertal period may enhance the mechanical competence of the skeleton, perhaps offering an important strategy for osteoporosis prevention if the benefits are maintained.
History
Journal
Journal of Bone and Mineral ResearchVolume
14Issue
7Pagination
1222 - 1230Publisher
Wiley-Blackwell PublishingLocation
Hoboken, N.J.Publisher DOI
ISSN
0884-0431Language
engPublication classification
C1.1 Refereed article in a scholarly journalCopyright notice
1999, American Society for Bone and Mineral ResearchUsage metrics
Categories
Keywords
Body ConstitutionBone DevelopmentBone and BonesCalcaneusChildCohort StudiesDietExerciseFingersGymnasticsHumansInsulin-Like Growth Factor ILongitudinal StudiesMaleProspective StudiesRadiusStress, MechanicalUltrasonographyVideo RecordingWeight-BearingScience & TechnologyLife Sciences & BiomedicineEndocrinology & MetabolismBONE-MINERAL DENSITYELDERLY WOMENMASSOSTEOPOROSISCHILDRENADOLESCENTSPUBERTYGROWTHINTERVENTIONATTENUATION