underdeveloped glutes. Don’t fall into that trap. Understand that the gluteus maximus is responsible
for several joint actions. Concentric contractions (muscle fibers shorten) extend the hip, laterally
rotate the hip, abduct the hip (move leg away from center of body), and posteriorly (toward front)
tilt the pelvis. The gluteus maximus functions isometrically (with little shortening of muscle) and
eccentrically (muscle lengthens during contraction) to prevent or absorb hip flexion and to produce
internal hip rotation, hip adduction (brings leg toward center of body), and anterior (backward)
pelvic tilt. The gluteus medius and gluteus minimus are responsible for hip abduction in addition to
hip rotation, either internal or external depending on the muscle fibers and level of hip flexion.