The purpose of this study was to investigate the relationships between muscle mass or muscle power and bone mineral density in 43 postmenopausal women. Single photon absorptiometry was used to measure the bone mineral density and bone width of the calcaneuse. Isotonic muscle power of knee extensions (KE), knee flexions and incline squats (ISQ) were measured, using the power processor (VINE Co., Ltd.) . Statistical analysis demonstrated a significant positive correlation (p<0.05) between bone mineral density and lean body mass or muscle thickness. Although, bone mineral density was not significantly correlated with body mass index or fat mass, it was significantly corre-lated with leg muscle power. Further, the bone mineral density was also positively correlated with muscle contraction speed in the motion of KE (p<0.01) and ISQ (p<0.05), but not with muscle strength. This data suggest that the bone mineral density is closely related to the muscle power and/or speed rather than the muscle strength in postmenopausal women.
