Step length reductions in advanced age: The role of ankle and hip kinetics
Step length reductions in advanced age: The role of ankle and hip kinetics
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DOI：
10.1093/gerona/51a.6.m303
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发表时间：
1996-11-01
影响因子：
5.1
通讯作者：
Ounpuu, S
中科院分区：
文献类型：
--
作者：
Judge, JO;Davis, RB;Ounpuu, S
背景衰老与步态速度的降低有关，这是由于步长缩短。本研究探讨了关节动力学和步长之间的关系。三维步态运动学和动力学进行了测量，在26个老年人（平均年龄79岁）和32个年轻的受试者（平均年龄26岁）在通常的步伐步态。步态措施，在最大速度在五个老年人。采用等速肌力计测量老年受试者的下肢力量。当校正腿长时，老年人在正常步态中的步长缩短了10%（分别为0.65 +/- .07，0.74 +/- .04/腿长，p <0.001）。老年人在站立后期踝关节跖屈减少（13 +/- 5度，17 +/- 5度，p = 0.02），踝关节跖屈肌功率降低（分别为2.9 +/- 0.9 W kg（-1），3.5 +/- 0.9 W kg（-1），p = 0.007）。踝关节力量与站立后期的跖屈肌力量相关（r = 0.49，p <0.001）。当根据步长校正步态动力学时，老年受试者在后期站立时的髋屈肌力量比年轻受试者高16%（估计效应：0.15 W kg（-1），p = 0.002）。老年受试者不能在最大速度下增加踝跖屈肌力量，但髋屈肌力量增加了72%（1.1 +/- 0.3 W kg（-1）至1.9 +/- 1.0 W kg（-1），p = 0.02）。年龄较大的受试者在步态的后期站立阶段具有较低的踝跖屈肌功率，并且似乎通过增加髋屈肌功率来补偿跖屈肌功率的减少。适当的踝跖屈肌训练可能对老年人保持步长很重要。
Background. Aging is associated with a reduction in gait velocity, which is due to a shortened step length. This study investigated the relationship between joint kinetics and step length.Methods. Three-dimensional gait kinematics and kinetics were measured during usual pace gait in 26 older subjects (average age 79) and in 32 young subjects (average age 26). Gait measures were obtained at maximal velocity in five older subjects. Lower extremity strength was measured in the older subjects on an isokinetic dynamometer.Results. Older persons had a 10% shorter step length during usual gait, when corrected for leg length (.65 +/- .07, .74 +/- .04/leg length, respectively, p < .001). Older persons had reduced ankle plantarflexion during late stance (13 +/- 5 degrees, 17 +/- 5 degrees, p = .02) and lower ankle plantarflexor power (2.9 +/- 0.9 W kg(-1), 3.5 +/- 0.9 W kg(-1), respectively, p = .007). Ankle strength was associated with plantarflexor power developed during late stance (r = .49, p < .001). When gait kinetics were corrected for step length, the older subjects developed 16% greater hip flexor power during late stance than younger subjects (estimate of effect: .15 W kg(-1), p = .002). Older subjects were unable to increase ankle plantarflexor power at maximal pace, but increased hip flexor power 72% (1.1 +/- 0.3 W kg(-1) to 1.9 +/- 1.0 W kg(-1), p = .02).Conclusions. Older subjects had lower ankle plantarflexor power during the late stance phase of gait and appeared to compensate for reductions in plantarflexor power by increasing hip flexor power. Appropriate training of ankle plantarflexor muscles may be important in maintaining step length in advanced age.