16주간 근력운동에 따른 국소부위 골밀도의 변화와 상관관계 특성

The Effects and Correalation Characteristics on Local Bone Mineral Densities of Mild Strength Exercise in Middle - Aged Women

This study was performed to suggest the effects of mild strength exercise on local bone densities and the correlation characteristics among the various variables, body composition and local bone densities, in middle-aged women. The subjects were volunteered in 16 women being resident in the local community. Their ages were within 47.6±4.8 years. Body composition were analyzed by the Bioelectrical Impedence method(model; In Body.1999, Biospace Co. Korea), and local bone densities were measured by DEXA method(PIXI 51008 model, Lunar Co. USA). All subjects performed mild strength exercise, 3 times/week during 16 weeks. Exercise session were constructured into warm up by walking and stretching 20min. and muscle training on the sites that measure the bone densities during 30 minutes. Results in this study were as following. Body compositions were significantly reduced in muscle volume 2.6% and body fat 3.63% after 16weeks. Local bone densities in the forearm were nonsignificantly 0.73% at 1/3 site and 1.24% at middle site, and ulna distal site was significantly decreased in 4.51% after 16wks. but total bone density in the forearm was reduced 1.4% nonsignificantly in the postexercise. Lumbar site was, also, increased 0.4% without significance at lumbar 2-4 level. All of three femoral sites, however, did increased nonsignificantly 1.59% at neck, 1.06% at greater trochanter, and 5.62% at ward’s triangle in the postexercise. Serum calcium and osteocalcin values were significantly higher 13.7%(P=0.000) and 54.1%(0.01) than before. Weight variable was significantly correlated with a bone density at a femoral neck site(r=0.34, P=0.05) and BMI had the significant correlation with neck(r=0.43, P=0.01) and greater trochanter(r=0.44, P=0.01) in femur. Correlation characteristic among local bone densities appeared higher(r=0.41-0.71, P=0.01) between the lumbar and femur sites than those(r=0.38, P=0.02) between the lumbar and forearm sites. there was middle level(r=0.45-0.58, P=0.001)between forearm and femur site. In conclusion, it was suggested that local bone density in middle-aged women can be increase through mild strength exercise over mechanical stress of ordinary lifestyle during 16 weeks.