Gracilis

legsMusculus gracilis

The gracilis is the long thin strap running down the inside of your thigh past the knee. It is the only adductor that crosses the knee, so it bends the knee as well as pulling the leg in.

Gracilis is a long, flat, narrow muscle on the innermost edge of the thigh, running from the pubic bone all the way down past the knee to the inside of the shin. It is the most superficial and most medial of the adductors and the only one you can trace along the whole inner edge of the thigh.

Crossing the knee is what makes it different from the rest of the group. It adducts the thigh like the others, and it also flexes the knee and turns the lower leg inward when the knee is bent — actions it shares with the inner hamstrings rather than with the adductors.

It attaches as part of the pes anserinus, the three-tendon convergence below the inside of the knee that it shares with the sartorius and the semitendinosus. Three muscles from three different regions and three different nerves arrive at the same small patch of bone.

Its name means slender, which describes it accurately. It is thin enough that it is frequently harvested as graft tissue in reconstructive surgery without significant functional loss — a practical measure of how much of the adductor group's work it actually does.

Training notes

It is loaded by adduction work like the rest of the group, and additionally by knee flexion — so leg curls train it, which is not true of any other adductor.

Wide-stance squats, sumo deadlifts and lateral lunges all load it in adduction, and it is stretched at long lengths in a Cossack squat.

Because it crosses two joints, movements that adduct the hip while the knee is straight put it at its longest, which is the position it is most often trained in and most often stretched in.

Anatomy

Origin
  • Body and inferior ramus of the pubis
Insertion
  • Upper medial surface of the tibia, as part of the pes anserinus
Actions
  • Adducts the thigh
  • Flexes the knee
  • Internally rotates the lower leg when the knee is bent
Innervation
Obturator nerve (L2–L3)

Exercises

Antagonists

Synergists