Department of Physical Therapy, University of Delaware, United States.
J Sci Med Sport. 2010 Jan;13(1):161-6. doi: 10.1016/j.jsams.2009.01.001. Epub 2009 Apr 1.
Isokinetic fatigue protocols have been used to determine the relative importance of lower extremity musculature to the maintenance of balance. However, these protocols are not representative of physical activity, thus the recommendations based on these findings may be inappropriate. Therefore, purpose of this investigation was to use a completely within subjects design to examine the effects of a functional ankle and hip fatigue protocol on postural control during single leg stance. All testing was completed in a health and wellness facility where 18 healthy recreationally active university students (nine female, nine male: 21.2+/-1.96 years, 72.2+/-17.8 kg, 170.4+/-10.12 cm) volunteered to participate. Testing consisted of functionally fatiguing the ankle plantar flexors and dorsiflexors as well as the hip flexors and extensors. Postural control was assessed with two pre- and post-fatigue 20s trials during single leg stance. Three measures of dynamic balance: the overall, medial/lateral, and anterior/posterior stability index were calculated using the Biodex Stability System at stability level 4. Three separate 2-way repeated measure ANOVAs indicated that fatigue of both the ankle (plantar flexors, dorsiflexors) and hip (flexors, extensors) musculature led to postural control impairments for the medial-lateral stability index (p<0.01), and anterior-posterior stability index (p<0.01). However, only ankle fatigue resulted in deficits in the overall stability index were (p<0.01). Furthermore, neither fatigue protocol impaired single leg stance postural control more than the other (p>0.05). Our results contradict previous isokinetic fatigue protocol findings, which indicate that proximal musculature fatigue results in greater postural control deficits.
等速疲劳协议已被用于确定下肢肌肉对平衡维持的相对重要性。然而，这些协议并不代表身体活动，因此基于这些发现的建议可能是不恰当的。因此，本研究的目的是使用完全在个体内的设计来检查功能性踝关节和髋关节疲劳方案对单腿站立时姿势控制的影响。所有测试均在健康和保健设施中完成，18 名健康、有规律运动的大学生（9 名女性，9 名男性：21.2+/-1.96 岁，72.2+/-17.8kg，170.4+/-10.12cm）自愿参加。测试包括功能性地疲劳踝关节跖屈肌和背屈肌以及髋关节屈肌和伸肌。姿势控制在单腿站立时通过两个疲劳前和疲劳后 20 秒试验进行评估。使用 Biodex 稳定性系统在稳定性水平 4 下计算动态平衡的三个指标：整体、内侧/外侧和前/后稳定性指数。三个单独的 2 因素重复测量方差分析表明，踝关节（跖屈肌、背屈肌）和髋关节（屈肌、伸肌）肌肉的疲劳导致内侧/外侧稳定性指数（p<0.01）和前/后稳定性指数（p<0.01）的姿势控制受损。然而，只有踝关节疲劳导致整体稳定性指数出现缺陷（p<0.01）。此外，两种疲劳方案都没有导致单腿站立姿势控制的损伤比另一种更大（p>0.05）。我们的结果与以前的等速疲劳协议结果相矛盾，该结果表明，近端肌肉疲劳导致更大的姿势控制缺陷。
