Activation of back and lower limb muscles during squat exercises with different trunk flexion.
[Purpose] The purpose of this study was to investigate the activation of back and lower limb muscles in subjects who were performing a squat exercise at different angles of trunk flexion. [Subjects and Methods] Twenty healthy subjects (age 21.1± 1.8 years, height 168.7 ± 8.2 cm, weight 66.1 ± 12.3 kg) volunteered. The activation of the erector spinae muscle, rectus femoris muscle, gluteus maximus muscle and biceps femoris muscle was observed while the subjects performed squat exercises with a trunk flexion of 0°, 15°, and 30°. [Results] The erector spinae muscle, gluteus maximus muscle, and biceps femoris muscle were activated more during the squat exercise with the trunk flexion at 30° than the exercise with the trunk flexion at 0°. The rectus femoris muscle showed a tendency to decrease as the truck flexion increased. [Conclusion] Squat exercise be executed while maintaining an erect trunk posture if one wishes to strengthen the quadriceps muscle while reducing the load on the lower back.
Department of Physical Therapy, Dong-Eui Institute of Technology, Republic of Korea.
Tae-Sik
TS
Lee
Department of Physical Therapy, Dong-Eui Institute of Technology, Republic of Korea.
Min-Young
MY
Song
Department of Physical Therapy, Dong-Eui Institute of Technology, Republic of Korea.
Yu-Jeong
YJ
Kwon
Muscle activity; Squat exercise; Trunk flexion