The Iliotibial Band has caused stress to runners and PTs since the beginning of time. One thing is for sure, once you have been plagued by ITB syndrome, you will forever be afraid of it. The mysterious ITB is only a fraction of muscle tissue and contains mostly tendon tissue.
Researchers are looking at this fact to learn more about this wacky structure and why it plague runners.
A study from Harvard University looked at how the ITB stores energy while running. A three-dimensional geometric system was used to measure the force-length properties of the ITB, TFL and glut max. The measurement points were placed at the hip and knee of 5 different legs and EMG studies were done at the same time to measure the glut max and TFL strain separately.
The glut max is responsible for the posterior force on the ITB while the TFL is responsible for the anterior force, basically proving the ITB is always working while running. The researchers found that force produced by both the glut max and TFL stretch the ITB, which causes energy storage in the muscle tendon units of the ITB. The posterior aspect of the ITB stores more energy due to the greater muscle force of the glut med. They also found at higher speeds, the ITB stores more energy.
Mobility in the glut max and the TFL is crucial to creating more energy, but keeping the ITB mobile is just as important. If the muscle-tendon junction of the ITB is too tight it will not be able to store energy from the attached muscles. Foam rolling and soft tissue massage are the best ways to keep the muscle tendon junction healthy and happy!
Eng, C., Arnold, A., Lieberman, D., Biewener, A. The capacity of the human iliotibial band to store elastic energy during running. Journal of Biomechanics. 48(2015) 3341-3348.
Kathleen Leninger, DPT