This study examined an effectiveness of a postural instruction in order to cause to pelvic anterior inclination on a jumping exercise. The word of the postural instruction was “expand your chest and look forward”. Fifteen male track and field athletes (undergraduates and graduates) performed standing long jump (SLJ) at the maximum. The performance with a postural instruction was compared with one without it.
The pelvic anterior inclination in the initial posture of SLJ with a postural instruction was significantly higher than one without it. The muscle-tendon complex length at the lowest position of C.G. of gluteus maximus of SLJ with a postural instruction was significantly longer than one without it. And muscle activities of gluteus maximus of SLJ with a postural instruction at the eccentric and the concentric phases were lower than one without it.
Therefore the postural instruction in order to cause to pelvic anterior inclination on the SLJ seemed to cause the gluteus maximus stretched at the eccentric phase and exerted an effective force output at the concentric phase.
