Obuchi S, Sato H, Shibata H, Kojima M, Shirataka M, Maeda M
School of Allied Health Sciences, Kitasato University, Kanagawa 228-8555, Japan.
School of Medicine, Hiroshima University, Hiroshima 734-8551, Japan.
J Jpn Phys Ther Assoc. 2000;3(1):7-11. doi: 10.1298/jjpta.3.7.
Past intervention studies on bone remodeling for preventing osteoporosis in elderly women often lack sufficient description of the intensity of the exercise, though bone remodeling is dependent on applied force at specific sites. The effectiveness of exercise in increasing bone density cannot be defined without sufficient description of the intensity and targeted site of the exercise. We conducted kinetic and kinematic analyses of the lower extremities in order to categorize exercise in terms of compression force applied at the proximal end of the femur, to formulate guidelines for prescribing exercise to elderly women. Thirty healthy women aged 18-24 participated in the study. Joint compression force at the proximal end of the femur was measured with the aid of motion analysis devices under several conditions of impulsive loading. Joint compression force at the proximal end of the femur was estimated for twenty-two exercise regimes varying from low to high-impact exercises, including jumping off, stepping down, vertical jumping, and dropping down after heel raises. Some exercises appear to be inappropriate for exercise intervention, because the variability for these exercises is high. Most of the jumping exercises, with coefficients exceeding 0.36, were excluded from further analysis. Of the remaining exercises, four were categorized as statistically different loads, as determined by a posthoc test of one-way analysis of variance of joint compression force. These included jumping off a 10 cm platform, stepping down from a 20 cm platform with the knees in the extended position, stepping down from a 20 cm platform with the knees in a relaxed position, and heel dropping at 80 cycles per minute with the knees in a relaxed position. The joint compression forces during these exercises were 2.32 ± .81, 1.81 ± .59, 1.45 ± .59, and 1.00 ± .27 times as much as the subject's body weight, respectively.
过去针对老年女性预防骨质疏松症的骨骼重塑干预研究，虽然骨骼重塑取决于特定部位所施加的力，但往往对运动强度缺乏足够描述。如果没有对运动强度和目标部位进行充分描述，就无法确定运动在增加骨密度方面的有效性。我们对下肢进行了动力学和运动学分析，以便根据股骨近端所施加的压缩力对运动进行分类，从而为老年女性制定运动处方指南。30名年龄在18至24岁之间的健康女性参与了这项研究。在几种冲击负荷条件下，借助运动分析设备测量了股骨近端的关节压缩力。针对从低强度到高强度的22种运动方式，包括跳下、下台阶、垂直跳跃以及踮脚后落下，估算了股骨近端的关节压缩力。有些运动似乎不适合用于运动干预，因为这些运动的变异性很高。大多数系数超过0.36的跳跃运动被排除在进一步分析之外。在其余运动中，根据关节压缩力的单因素方差分析事后检验，有4种运动被归类为具有统计学差异的负荷。这些运动包括从10厘米高的平台跳下、伸直膝盖从20厘米高的平台下台阶、放松膝盖从20厘米高的平台下台阶以及膝盖放松状态下每分钟80次的踮脚落下。这些运动过程中的关节压缩力分别是受试者体重的2.32±0.81倍、1.81±0.59倍、1.45±0.59倍和1.00±0.27倍。
