| ObjectiveTo quantify the coordination patterns and coordination variability of the lower limbs;To detect the synergistic effect in inter-joint coordination;To analyze the influence of gait speeds on the changes of the coordination pattern of the lower limbs.MethodsSeventeen healthy male college students were selected as the research objects.The subjects were asked to walk at three speeds of slow,medium and fast,respectively.A 7-lens Motion infrared camera(200Hz)was used to collect the kinematic signals during the walking process of the subjects.At each speed,calculated the continuous relative phase(MACRP),the phase deviation(DP)and the variance variability(V‖)parallel to the uncontrolled manifold(UCM)space,the variance variability(V⊥)in the space orthogonal to the UCM space and their synergy S of the intra-limb(hip-knee,kneeankle)coupling and the inter-limb(hip-hip,knee-knee,ankle-ankle)coupling according to the processed angle and angular velocity.A two-factor repeated measurement analysis of variance was used to compare the effects of different gait phases(the first double support phase,single support phase,second double support phase,swing phase)and different gait speeds(fast,medium,and slow)on them.Results1.There were significant differences in the duration of the asynchronous action phase at the three gait speeds(p<0.01).2.The MACRP results showed that there was an interaction between each gait phase and gait speed in the coordination mode of joint coupling except for ankle-ankle coupling.In the hip-knee coupling,the coordination pattern became more out-of-phase with the time of the gait cycle.The in-phase pattern was the strongest in the single support phase during slow walking(p<0.01).Knee-ankle coupling had little difference in the support period.The swing phase was more out-of-phase,and the out-of-phase pattern was strongest in the second double support phase during fast walking(p<0.01).In the hip-hip coupling,the coordinated development was in-phase to out-of-phase to in-phase to out-of-phase.The coordination mode in the single stance phase and swing phase during slow walking were more in-phase than the fast and slow speeds(p<0.01).In the knee-knee coupling,the coordination pattern was not much different throughout the gait cycle.During fast walking,it was more out-of-phase at all stages than the medium and slow speeds(p<0.01),The ankle-ankle coupling coordination development was out-of-phase to in-phase to out-of-phase to in-phase and there was no significant difference between speeds.3.The DP results showed that there was an interaction between each gait phase and gait speed in the coordination variability of joint coupling except for knee-kneecoupling.In the hip-knee coupling,the variability gradually increased in each stage of the support phase,and decreased during the swing phase.The variability in the first double support phase and the swing phase in the slow speed was significantly higher than that in the fast and medium speed(p<0.01).The development of knee-ankle coupling variability showed a tendency to first decrease,then increase and then decrease.The variability at slow speed during the single support phase and swing phase was significantly higher than that during the fast and medium speeds(p<0.01).In the hip-hip coupling,the variability showed a tendency to first increase,then decrease,and then increase.During the entire support period,the slow speed was higher than that of the fast and medium speeds(p<0.01).The variability of knee-knee coupling and ankle-ankle coupling decreased first,then increased,and then decreased.In the ankle-ankle coupling,the slow speed during the single support phase and the swing phase was significantly higher than that during the fast and medium speeds(p<0.01).4.In the UCM analysis,there was an interaction between each gait phase and gait speed in the synergistic effect of joint coupling except for knee-knee coupling.In the hip-knee coupling,the synergistic effect gradually increased during the gait cycle,and the degree of synergy was greatest during the swing phase.There was no significant difference in the influence of gait speed on the synergistic effect in each stage.Knee-ankle coupling was except in the second double support Except for the significant synergistic effect(p<0.01),there was no synergistic effect in the other three stages or the synergistic effect was not significant,and the synergistic effect was the lowest in the first double support phase at slow speed.In the hip-hip coupling,there had a synergistic effect in all stages of gait,and there was no significant difference between gait speed.Knee-knee coupling also had a synergistic effect in all stages of gait,and the synergistic effect of slow speed was higher than that of fast and medium speed(p<0.01).The ankle-ankle coupling only had a significant synergistic effect(p<0.01)during the two dual support periods,and there was no significant difference between the speeds.Conclusion and Suggestion1.The coordination pattern of lower extremity joints during walking is that the proximal joints(hip-knee,hip-hip and knee-knee coupling)are more in-phase in the dual support period,more out-of-phase in the single support period and swing period,and there is a synergistic effect during the entire cycle.But the remote joints(kneeankle and ankle-ankle coupling)are more out-of-phase in the dual support period,more in-phase in the single support period,and only have a synergistic effect in the dual support period.2.During the double support period,the coordination pattern between the remote joints was more volatile than that between the proximal joints.3.The coordination pattern between the joints during fast walking is more out-ofphase,and there is greater coordination variability between the joints during slow walking.4.Because of the greater coordination variability,slow walking is not necessarily more stable than fast walking,but the potential risk of cumulative injury is lower.People who are accustomed to fast walking can slow down their pace appropriately. |
PDF Full Text Request