鞍座高度对骑行时髌股关节力学特征影响的研究

Effects of Saddle Heights on Patellofemoral Joint Force and Stress during Cycling

目的:探讨不同鞍座高度对稳定骑行状态下髌股关节载荷的影响,为科学健身骑行提供理论参考。方法:20名受试者以随机的顺序完成(中等高度座高,Medium;自选高度座高,Preferred;较低高度座高,Low;较高高度座高,High)4种鞍座高度下的骑行,采用三维红外动作捕捉系统(200 Hz)、三维脚蹬测力台(1 000 Hz)同步采集受试者骑行状态下的右侧下肢髋、膝、踝关节运动学、踏板反作用力数据;使用三维分析软件(Visual 3D)、Matlab软件计算、分析连续10个踩踏周期的运动学、动力学指标。结果:采用较低的鞍座高度骑行时具有较大的股四头肌峰值肌力(P<0.05)、髌股关节峰值力(P<0.05),与较高的鞍座骑行相比具有较大的髌股关节峰值应力(P<0.05),同时髌股关节峰值力出现时膝关节屈曲角度更大(P<0.05);鞍座高度并没有影响髌股关节峰值应力出现时的膝关节角度(P>0.05)。结论:较低的鞍座高度骑行时,具有较大的股四头肌峰值肌力、髌股关节峰值力及髌股关节峰值应力,同时髌股关节峰值力出现时具有较大的膝关节角度。因此,从预防股髌关节疼痛综合症的观点出发,骑行时需对鞍座高度进行适当的调整,不建议采用较低的鞍座高度骑行。

Objective：Prior research indicates that overuse of forces and great angle movements at the knee joints during cycling may lead to a high risk of knee injury,including patellofemoral pain.The purpose of this study was to evaluate the effects of different saddle heights on patellofemoral joint force and stress during cycling.Methods：20 healthy subjects,serving as self-control,performed a cycling task with the saddle set at four different heights（Low,Medium,High,and Preferred）.Data across the four different saddle heights were collected by using 3 D Kinematics and pedal reaction force.The dependent variables were peak quadriceps,patellofemoral joint force,joint stress,and angle at knee joints.Results：Results from the MANOVA test showed an overall significant difference attributable to saddle height（P0.05）,indicated that,compared with High,Medium,and Preferred heights,performance at the Low saddle height showed greater peak quadriceps force,peak patellofemoral joint force,and peak patellofemoral joint stress（P0.05）.In addition,compared with High,Medium,and Preferred heights,the instant angle at the knee joint during the Low height performance was shown to be greatest at the peak of the patellofemoral joint force（P0.05）.No differences were observed,however,for the angle at the knee joint for the joint stress.Conclusion：Comparing to higher saddle positions during cycling,a low saddle height produced greater peak quadriceps force,patellofemoral joint force,patellofemoral joint stress,and greater knee angle shown at the peak of the patellofemoral joint force.These results suggest that cycling with a low saddle height may have a negative impact on patellofemoral joints.