Ricard G, Currier D P
Phys Ther. 1977 Sep;57(9):1013-5. doi: 10.1093/ptj/57.9.1013.
Twenty normal women were tested for maximal isometric contraction of the right knee extensor muscles. The knee was positioned in 60 degrees of extension and the hip at 120 degrees of extension, with and without a backrest. The purpose of the study was to determine whether the use of a backrest resulted in greater force than when not using a backrest when the angle of back inclination was held constant and the support was varied. The results indicated that the addition of a backrest, when the body assumes an optimal position, enables the knee extensors to generate greater force then when no backrest is used. A backrest adds to the comfort and support of the subject performing resistive knee exercise and should be incorporated into the design of knee exercise units.
对20名正常女性的右膝伸肌进行最大等长收缩测试。膝关节处于伸展60度、髋关节处于伸展120度的位置，测试时有的有靠背，有的没有靠背。本研究的目的是确定在背部倾斜角度保持不变且支撑不同的情况下，使用靠背是否比不使用靠背时产生更大的力量。结果表明，当身体处于最佳位置时，增加靠背能使膝伸肌比不使用靠背时产生更大的力量。靠背增加了进行抗阻膝关节运动的受试者的舒适度和支撑性，应纳入膝关节运动器械的设计中。
