年齡老化在下肢爆發力的生物力學分析

Biomechanical Analysis of Lower Limb Muscle Power in Elderly Individuals

鄭一中(I-Chung Cheng) ； 蔚順華(Shun-Hwa Wei) ； 劉復康(Fu-Kong Lieu) ； 蔡佩真(Pei-Chen Tsai)

《台灣復健醫學雜誌》 42卷3期 (2014/09) Pp. 147-152

https://doi.org/10.6315/2014.42(3)02

摘要

研究背景：過去幾十年來，台灣的老年人口快速增加，老化會導致下肢功能退化而阻礙高齡者執行日常生活工作的能力，降低生活品質，也會使得跌倒發生率提升，進而造成死亡。過去的實驗多把重心放在跌倒和下肢肌肉力量（muscle strength）的關聯，較少以生物力學觀點來探討老年人下肢力學爆發力的特色。客觀的量化評量高齡者坐到站能力有助於了解高齡者有無發生跌倒之危險性。研究目的：以坐到站此種功能性動作來探討健康族群高齡者、跌倒族群高齡者及健康年輕人在下肢肌肉產生力量及功能性動作速度之間的差異。實驗方法：徵召健康族群高齡者（17位）、跌倒族群高齡者（10位）以及健康年輕人（15位）進行評估，利用特製化單軸測力板上搭配訊號處理與類比轉換系統，來評估坐到站的力學參數以及時間參數。再使用單因子變異數檢定（One-way ANOVA）以及事後檢定（post hoc）比較各組之間的差異。顯著差異值p＜0.05。結果：評估參數顯示高齡者的力學參數（最大垂直地面反作用力、承重反應值、站立期的下肢標準化肌肉爆發力、站立期的波峰－波谷差值）數值皆較年輕族群低，而時間參數（總動作時間、反應期時間、穩定期時間）數值則較年輕族群長。結論：高齡族群與年輕族群相比，下肢爆發力小，動作執行策略緩慢，導致執行功能性活動時速度較慢，力量較小。而利用實驗的數值可客觀呈現健康族群高齡者、跌倒族群高齡者及健康年輕人在力學及時間參數之間的差異。

關鍵字

高齡者 ； 功能性動作 ； 肌肉爆發力 ； 測力板 ； 坐到站

並列摘要

Background: The aging process may contribute to a decrease in lower extremity function in elderly individuals, which in turn often causes a functional decrease in activities of daily living, loss in quality of life, and increase in risk of accidental falls. In the last few decades, numerous studies in elderly individuals have reported the relation between a high incidence of accidental falls and inadequate muscle strength. Unfortunately, few studies have provided insight about their individual muscle performance, such as the explosive muscle power, from a biomechanical prospective. Quantitative analysis of the sit- to- stand (STS) ability is a useful method in evaluating falling risk in elderly individuals. Purpose: To compare explosive muscle power in lower limbs during an STS test among elderly individuals who had an accidental fall in the past year, elderly individuals who did not have a fall, and young adults. Methods: Forty-two subjects volunteering to participate in this study were placed into one of the following groups: healthy elderly individuals without any falls (n=17), elderly individuals who had an accidental fall (n=10), and young adults (n=15). A single- axis force plate, data acquisition system and LabVIEW software were used to evaluate the biomechanical parameters in each group. One-way ANOVA and Scheffe multiple comparisons were used to measure the kinetic and time parameters of STS ability. The statistical significance was set at p＜0.05. Results: Values of kinetic parameters (maximum vertical ground reaction force, loading response, normalized explosive power, and rising peak- to- peak amplitude) of the healthy and accidental fall groups of elderly individuals were lower than that of the young adult group. Values of time parameters (total time, reaction time, stabilization time) of the healthy and accidental fall groups of elderly individuals were longer than that of the young adult group. Conclusion: This study presents differences in the kinetics parameters between three groups from a biomechanical prospective. Deterioration of strength and explosive power in the lower extremities might lead to a higher incidence of accidental falls in elderly individuals.

並列關鍵字

elderly individual ； functional movement ； explosive muscle power ； force plate ； sit-to-stand