Running is a great way to get exercise, if your ankles and knees will tolerate it:
Recently, I ran across a case of a young female patient with knee pain, with edema around the iliotibial band:
Although the edema is closely associated with the ITB, the preponderance of edema is superficial to the ITB, rather than deep to it, as would be expected for ITB friction syndrome.
This seemed a bit odd, so I picked up the phone and called the patient. She informed me that she had received a cortisone shot in this location about 3 hours prior to the MRI, and had a bruise in that location. A little clinical history can go a long way...
Thus, if you see edema concentrated in a focal area in the superficial soft tissues, without a history of trauma or infection, consider the possibilty of iatrogenic mischief. This is also true for other joints, such as the shoulder.
Vic David MD