Effects on electromyography activity and range of motion in lower limb from a novel hip flexor training machine under light and heavy resistance / 医用生物力学

ABSTRACT

Objective To investigate the effect of a novel hip flexor training machine on muscle activation and range of motion (ROM) in lower limb under the condition of different resistances. Methods Six volunteers performed consecutive rightly hip flexion and extension for 30 times under light or heavy resistance randomly on the training machine, and the muscle activity and ROM in lower limb during the movement were measured at the same time. Results The muscle activation of rectus abdominal, hip flexor muscles, gluteus maximum, rectus femoris and biceps femoris under heavy resistance was significantly higher than that under light resistance (P<0.05); the muscle activation of rectus abdominis, hip flexor muscles and rectus femoris at during the last 3 times were significantly higher than that at of the first 3 times under heavy resistance (P<0.05); under light resistance, only the muscle activation of erector spinae and rectus femoris during the last 3 times were significantly higher than that of the first 3 times. The ROM and angle of hip extension under heavy resistance were significantly smaller than those under light resistance. Conclusions Under the rational ROM of hip joint, this new hip flexor training machine can stimulate the hip flexion and extension muscles and other co-contraction muscles to accomplish the movement, especially under the condition of heavy resistance.