Proctor Kerry L, Adams William C, Shaffrath James D, Van Loan Marta D
Human Performance Laboratory, Exercise Biology Program, University of California, Davis, USA.
Med Sci Sports Exerc. 2002 Nov;34(11):1830-5. doi: 10.1097/00005768-200211000-00021.
We examined bilateral bone mineral density (BMD) in the arms of female college gymnasts to assess the relative contribution of high-impact loading forces versus daily activities on bone plasticity.
Twenty-five female collegiate gymnasts and 25 controls were studied. BMD of the lumbar spine, proximal femur, and whole body were assessed via dual energy x-ray absorptiometry. Upper-limb BMD was determined by custom analyses of the whole-body scans to examine arms individually.
BMD of gymnasts was significantly (P < 0.0001) greater than controls at all sites. Whole-body BMD was 8% higher in gymnasts (1.270 +/- 0.078 vs 1.175 +/- 0.073 g x cm(-2)), with 18-19% differences in the lumbar spine (1.427 +/- 0.144 vs 1.212 +/- 0.106 g x cm(-2), right proximal femur (1.298 +/- 0.101 vs 1.100 +/- 0.129 g x cm(-2)), and left proximal femur (1.293 +/- 0.111 vs 1.104 +/- 0.133 g x cm(-2)). Arm BMD was 17% greater in gymnasts, with higher values in both dominant (1.013 + 0.067 vs 0.875 + 0.066 g x cm(-2)) and nondominant (1.002 + 0.060 vs 0.849 + 0.062 g x cm(-2)) arms. Intragroup comparisons revealed a significantly (P < 0.0001) greater BMD in the dominant arm of the controls but no side-to-side difference in the arms of the gymnasts.
Upper-limb BMD followed use patterns in both gymnasts and controls, demonstrating that the forces imposed on the arms with gymnastics training enhanced BMD and resulted in no bilateral differences. These findings illustrate the association between gymnastics training and increased BMD throughout the body, suggesting that the high BMD values observed in gymnasts are due primarily to the activity itself rather than selection bias.
我们检测了女大学生体操运动员双臂的双侧骨密度（BMD），以评估高冲击力负荷与日常活动对骨骼可塑性的相对贡献。
对25名女大学生体操运动员和25名对照组人员进行了研究。通过双能X线吸收法评估腰椎、股骨近端和全身的骨密度。上肢骨密度通过对全身扫描进行定制分析来单独检测双臂确定。
体操运动员在所有部位的骨密度均显著高于对照组（P < 0.0001）。体操运动员的全身骨密度高8%（1.270±0.078 vs 1.175±0.073 g x cm(-2)），腰椎差异为18 - 19%（1.427±0.144 vs 1.212±0.106 g x cm(-2)），右侧股骨近端（1.298±0.101 vs 1.100±0.129 g x cm(-2)），左侧股骨近端（1.293±0.111 vs 1.104±0.133 g x cm(-2)）。体操运动员的手臂骨密度高17%，优势臂（1.013 + 0.067 vs 0.875 + 0.066 g x cm(-2)）和非优势臂（1.002 + 0.060 vs 0.849 + 0.062 g x cm(-2)）的值均更高。组内比较显示，对照组优势臂的骨密度显著更高（P < 0.0001），但体操运动员双臂无左右差异。
上肢骨密度在体操运动员和对照组中均遵循使用模式，表明体操训练施加在手臂上的力量增强了骨密度，且未导致双侧差异。这些发现说明了体操训练与全身骨密度增加之间的关联，表明体操运动员中观察到的高骨密度值主要是由于活动本身而非选择偏倚。
