"Symptoms of this condition are pain on the outside of the knee. Runners may experience the pain during a certain time during a run, especially downhill.  And also with bending and straightening the knee.  With rest relieving the pain.  This can be caused by weak hip muscles, wrong foot positioning when walking or running, overuse or sudden changes in your exercise routine. 

Seek the advice of your physiotherapist if you experience these symptoms."

http://www.sportsinjuryclinic.net/sport-injuries/knee-pain/iliotibial-band-syndrome

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