Effect of Different Speeding Strategy on Functional Compensation Mechanism and Lower Extremity Joint Kinetics during Walking in Healthy Older Women

Objective: To investigate the differentiation of functional compensation and the changes of lower extremity joint kinetics under three different speeding strategies during walking in healthy older women. Methods: The QTM and KISTLER were used to collect gait parameters from 27 healthy older women who performed normal and fast speed walking trials in a motion analysis laboratory. Subjects were classified into three groups based on different speeding strategies: 1) increase of cadence(G1, n=10); 2)increase of stride length(G2, n=8); 3) increase of stride length and cadence(G3, n=9). The peak joint moments, power and work during gait cycle were processed and analyzed. Results: There was no significant different in the joint loading of three groups in normal walking with similar speed, stride length and cadence(P<0.05). In addition, ankle and hip joint played a dominant role in the positive work ability(40%), and the energy was mainly absorbed by the knee joint(56%). From normal to fast walking, the peak value of lower extremity joint moment, power and work in ankle and knee joint were increased in varying degrees in G2 and G3 groups. In particular, the peak value of ankle joint moment, power and positive work were significantly increased in G2(P<0.05 or P<0.01), while the peak value of hip joint moment and power and positive work in the support phase of gait cycle in G1 group were increased significantly(P<0.01). Conclusion: Speeding strategy can change the lower extremity joint loading. The older women who increased their stride length or both stride length and cadence needs higher function in ankle and knee joint during fast speed walking. In addition, the one who increased stride cadence was more depended on the hip joint, which was due to the insufficient of ankle joint function and then the trend of functional compensation to the distal segment.