One common cause for irritation in the iliotibial (IT) band is a weak glute medius.
A new study had 12 women run on a treadmill for 30 minutes while measuring the activation of their glute medius muscle. Those subjects who had a history of an irritated IT band demonstrated lower levels of glute medius activation.
This study further elucidates Shirley Sahrmann’s concept of “synergistic dominance”. When the glute medius muscle becomes weak, the nearby muscles must work harder to compensate. In this case, one of the nearest muscles to the glute medius is the TFL, which attaches to the IT band. When the TFL is working too hard to make up for a weak glute medius, it is no surprise that the IT band becomes painful.
This study illustrates that for runners, exercises to strengthen the glute medius can be immensely beneficial.
Foch, E., Westbrooks, J. W., & Milner, C. E. (2017). Hip Neuromechanics In Women With And Without Previous Iliotibial Band Syndrome During A 30-minute Run: 3495 Board# 3 June 3 9. Medicine & Science in Sports & Exercise, 49(5S), 995.