Gluteus Maximus

legsMusculus gluteus maximus

The gluteus maximus is the largest muscle in the body and the main extensor of the hip. It is what drives you upward out of a squat and forward into a sprint.

Gluteus Maximus highlighted on an anatomical figure, from behind.
Where it sits, from behind.

The gluteus maximus is a thick, coarse-fibred sheet covering the back of the pelvis. It arises across a wide area — the back of the hip bone, the sacrum, the coccyx and the strong ligament running between sacrum and sitting bone — and runs down and outward at about forty-five degrees.

Most of it does not attach to the thigh bone at all. About three quarters of the fibres end in the iliotibial tract, the thick band of fascia running down the outside of the thigh to the knee; only the deeper lower quarter reaches the femur directly. That arrangement lets it influence the knee as well as the hip.

Its main action is hip extension, and it is at its most useful in the parts of that range where the hip is bent. Standing up from a deep squat, climbing a steep stair, running uphill and sprinting all recruit it heavily. Ordinary walking on level ground barely does, which is why it is possible to have an underdeveloped gluteus maximus while walking several miles a day.

It also turns the thigh outward, and its upper and lower fibres pull in opposite directions across the hip — the upper part helping to abduct and the lower part to adduct — so it is not a single-direction muscle even within itself.

Training notes

Two loading positions matter and most programs only have one. Squats, lunges and split squats load it with the hip deeply flexed; hip thrusts, glute bridges and back extensions load it at or near full extension. Someone who only squats has trained the first and left the second.

Range beats load for it. A squat that stops at parallel skips the range where the glutes take over from the quads, so depth is the first variable to fix before weight.

External rotation is part of what it does, which is why cues to screw the feet into the floor during a squat have a real mechanical basis — they recruit the glutes in a second direction at the same time.

Single-leg work is disproportionately valuable, because it demands hip extension and pelvic stability simultaneously, which is how the muscle actually works when walking and running.

Anatomy

Origin
  • Posterior gluteal line of the ilium and the rough bone behind it
  • Posterior surface of the lower sacrum and the side of the coccyx
  • Sacrotuberous ligament
  • Thoracolumbar fascia
Insertion
  • Iliotibial tract, taking about three quarters of the fibres
  • Gluteal tuberosity of the femur, taking the deeper lower quarter
Actions
  • Extends the hip, driving the thigh backward
  • Externally rotates the thigh
  • Abducts the thigh through its upper fibres and adducts it through its lower fibres
  • Steadies the pelvis and the extended knee through the iliotibial tract
Innervation
Inferior gluteal nerve (L5–S2)

Exercises

Antagonists

Synergists