Musculoskeletal loading from road cycling and distance running on bone bending strength and BMD in athletes

Abstract

The purpose of this study was to determine whether chronic sport training comprising of low or nonimpact musculoskeletal loading in road cycling (CYC) and distance running (RUN) were associated with tibial and ulnar bending strength and calcaneus and wrist BMD in male athletes. Method. Study subjects included 12 road cyclists (CYC), 12 distance runners (RUN) and 12 physically active nonathletic (CON). Tibial and ulnar bending strength (EI, Nm2) were assessed using a mechanical response tissue analyzer (MRTA), and BMD (g/cm2) of the wrist and calcaneus were assessed using a peripheral X-ray absorptiometry. Group means differences among the study groups were determined using ANCOVA. Results. Ulnar bending strength (EI, Nm2) of CYC were higher than CON (62.0 ± 20 vs 44.7 ± 9 Nm2, p< 0.05), but not RUN. Tibial bending strength (EI, Nm2) of CYC and RUN were not higher than CON. Calcaneus BMD of RUN was higher than CON (0.666 ± 0.07 vs 0.579 ± 0.06 g/m2, p<0.05), but not CYC. Wrist BMD of CYC was not higher than (p = 0.07) RUN and CON. Conclusion. Chronic engagement in CYC training induces osteogenic adaptation for increased ulnar bending strength and RUN training induces increased calcaneus BMD.