There’s a little fist-shaped muscle in the hip, right under the bony ridge of the pelvis, where your pants pocketsbegin. It’s called the tensor fascia lata. It hooks on to the iliotibial band, the long tendon that runs all the waydown the outside of the thigh, across the knee, to the lower leg. Small though it may be, this muscle helpsextend your knee, going to work during the last 15 percent of movement and then holding on to help keep yourknee extended. (If you tighten your knee and hold it front of you, you can feel how tight the muscle andtendon become. Simply run your fingers from the muscle just below the point of your hip down the outside ofyour leg to the knee.)
When you bend your knee, the tensor fascia lata helps flex it as well. But if your quads or hamstringsare weak, the tensor fascia lata is forced to bear too much of the load. Weak thigh muscles can lead toirritation of the tensor fascia lata, as well as to iliotibial band tendinitis (see “Iliotibial Band Tendinitis,” pp. 75-76).
+ What to do about it + Strengthen the thigh muscles, the quads especially, and stretch and strengthen the tensor fascia lata. Side-leg raises will strengthen the muscle; crossing your leg behind the other—the cross-leg stretch—will stretch it. (See pp. 92-93 in chapter 5, “The Knee,” for illustrations of exercises that stretchand strengthen this muscle.)