Adlerton Anna-Karin, Moritz Ulrich, Moe-Nilssen Rolf
Institute for Musculoskeletal Diseases, Department of Physical Therapy, Lund University, Lund, Sweden.
Physiother Res Int. 2003;8(4):187-99. doi: 10.1002/pri.289.
The control of balance is vital in many sporting activities as well as in activities of daily life. In order to treat deficiencies properly valid and reliable methods are needed to evaluate different aspects of stability. Muscle fatigue has been proposed to cause a change in postural control strategy, and the use of different tools and variables might therefore elucidate these changes. The aims of the present study were: to investigate if forceplate and accelerometer measurements about postural control during one-legged stance indicate changes in postural control strategy after fatiguing exercise; and to investigate the correlation between forceplate and accelerometer measurements obtained before and after fatiguing exercise.
The study used an experimental design. Twenty-three healthy women (mean age 26.8 years; range 20-34 years) were studied. Forceplate and accelerometer data were obtained simultaneously and consisted of measures of centre of pressure movements and horizontal trunk acceleration in medio-lateral and antero-posterior directions. The calf muscles of the right leg were fatigued by repeated heel rises.
The average amplitude of centre of pressure movements and trunk acceleration increased, whereas the average velocity of centre of pressure movements decreased during fatigue. These changes indicate a change of movement strategy. Moderate correlation between trunk acceleration and centre of pressure movements was seen, confirming the link between the variables, but indicating that different aspects of the ability to control balance were measured.
Calf muscle fatigue has a short-lasting effect on body balance, with measurements indicating a change in postural control strategy. Different tools and variables are needed to identify different balance control strategies. The procedures used in the present study may be modified to identify subjects with inadequate capacity to choose between balance control strategies; they are also applicable in clinical settings outside a laboratory environment.
平衡控制在许多体育活动以及日常生活活动中至关重要。为了妥善治疗平衡方面的缺陷，需要有效且可靠的方法来评估稳定性的不同方面。有人提出肌肉疲劳会导致姿势控制策略发生变化，因此使用不同的工具和变量可能会阐明这些变化。本研究的目的是：研究测力板和加速度计在单腿站立期间对姿势控制的测量是否表明疲劳运动后姿势控制策略发生了变化；以及研究疲劳运动前后获得的测力板和加速度计测量值之间的相关性。
本研究采用实验设计。对23名健康女性（平均年龄26.8岁；范围20 - 34岁）进行了研究。同时获取了测力板和加速度计数据，这些数据包括压力中心运动以及躯干在内外侧和前后方向的水平加速度的测量值。通过反复踮脚跟使右腿小腿肌肉疲劳。
在疲劳过程中，压力中心运动的平均幅度和躯干加速度增加，而压力中心运动的平均速度降低。这些变化表明运动策略发生了改变。观察到躯干加速度与压力中心运动之间存在中度相关性，证实了这些变量之间的联系，但表明测量的是控制平衡能力的不同方面。
小腿肌肉疲劳对身体平衡有短期影响，测量结果表明姿势控制策略发生了变化。需要不同的工具和变量来识别不同的平衡控制策略。本研究中使用的程序可以进行修改，以识别在平衡控制策略之间选择能力不足的受试者；它们也适用于实验室环境之外的临床环境。
