Morcelli Mary Hellen, LaRoche Dain Patrick, Crozara Luciano Fernandes, Marques Nise Ribeiro, Hallal Camilla Zamfolini, Gonçalves Mauro, Navega Marcelo Tavella
1 São Paulo State University.
2 University of New Hampshire.
J Appl Biomech. 2018 Aug 1;34(4):270-277. doi: 10.1123/jab.2016-0354. Epub 2018 Jun 30.
The aim was to compare torque and rate of torque development of lower limb muscles between older women with functional and slow gait speeds to determine which muscle group is the best predictor of functional gait speed, and to establish strength thresholds needed for functional walking speed. Torque and rate of torque development of hip, knee, and ankle muscles were measured in older women who were divided in 2 groups according to gait speed: slow gait speed (<1.22 m·s) and functional gait speed (≥1.22 m·s). For each muscle group, 3 maximal isometric contractions were performed, and peak torque and rate of torque development were recorded. Older women with slow gait speed had lower peak torque than older women with functional gait speed for hip extension (28%), knee flexion (15%), knee extension (14%), and plantar flexion (16%) (all Ps < .05). Older women with slow gait speed had lower peak rate of torque development for hip flexion (29%), hip extension (37%), knee flexion (34%), knee extension (33%), and plantar flexion (19%) (all Ps < .05). Knee extension peak rate of torque development and hip extension peak torque were the better predictors of functional gait speed with thresholds of 2.96 N·m·s·kg and 1.26 N·m·kg, respectively.
目的是比较步态功能和速度缓慢的老年女性下肢肌肉的扭矩和扭矩发展速率，以确定哪组肌肉是功能步态速度的最佳预测指标，并确定功能性步行速度所需的力量阈值。根据步态速度将老年女性分为两组：步态速度缓慢（<1.22 m·s）和步态功能正常（≥1.22 m·s），测量她们髋部、膝盖和脚踝肌肉的扭矩和扭矩发展速率。对每组肌肉进行3次最大等长收缩，并记录峰值扭矩和扭矩发展速率。步态速度缓慢的老年女性在髋部伸展（28%）、膝盖弯曲（15%）、膝盖伸展（14%）和足底弯曲（16%）时的峰值扭矩低于步态功能正常的老年女性（所有P值<0.05）。步态速度缓慢的老年女性在髋部弯曲（29%）、髋部伸展（37%）、膝盖弯曲（34%）、膝盖伸展（33%）和足底弯曲（19%）时的峰值扭矩发展速率较低（所有P值<0.05）。膝盖伸展扭矩发展峰值速率和髋部伸展峰值扭矩分别以2.96 N·m·s·kg和1.26 N·m·kg为阈值，是功能步态速度的更好预测指标。
