Bone bending strength and BMD of female athletes in volleyball, soccer, and long-distance running.

Purpose: The purpose of the study was to determine whether sports training comprised of (1) high-impact loading sport in volleyball (VOL), (2) odd impact loading sport in soccer (SOC), and (3) low impact sport in distance running (RUN) were associated with tibial bending strength and calcaneus bone mineral density (BMD), and ulnar bending strength and wrist BMD.

Method: Female athletes comprised of 13 VOL, 22 SOC, and 22 RUN participated in the study. Twenty-three female non-athletes (NA) served as the comparison group. Tibial and ulnar bending strength (EI, Nm) were assessed using a mechanical response tissue analyzer (MRTA). Calcaneus and wrist BMD were assessed using a peripheral X-ray absorptiometry. Group means differences among the study groups were determined using ANCOVA with age, weight, height, percent body fat, ethnicity/race, and training history serving as covariates.

Results: Tibial EI of VOL (228.3 ± 138 Nm) and SOC (208.6 ± 115 Nm) were greater (p < 0.05) compared to NA (101.2 ± 42 Nm). Ulnar EI of SOC (54.9 ± 51 Nm) was higher (p < 0.05) than NA (27.2 ± 9 Nm). Calcaneus BMD of VOL (0.618 ± 0.12 g/cm), SOC (0.621 ± 0.009 g/cm), and RUN (0.572 ± 0.007 g/cm) were higher (p < 0.05) than NA (0.501 ± 0.08 g/cm), but not different between athletic groups. Wrist BMD of VOL (0.484 ± .06 g/cm) and SOC (0.480 ± 0.06 g/cm) were higher (p < 0.05) than NA (0.443 ± 0.04 g/cm).

Conclusions: Female VOL athletes exhibit greater tibial bending strength than RUN and NA, but not greater than SOC. Female SOC athletes exhibit greater ulnar bending strength and wrist BMD than NA.