Q: I went to a good running store recently to buy new shoes, and after watching me run, the sales associate told me that I pronate. What is pronation?
A: In simple terms, perhaps over-simplified, pronation is the rolling in of your feet when the foot impacts the ground during running or walking. Pronation is really a complex three-dimensional motion of the joint located just below the ankle – the subtalar joint. This three-dimensional movement is what allows you to rotate your ankle in circles.
Pronation is a normal movement, just like flexion and extension of other joints. When talking about pronation, runners are usually referring to over-pronation or compensatory pronation. That is, your foot pronates more than normal and/or pronates to compensate for a position or motion of your leg. A good example of how limb position affects pronation is the compensation for knock-knees. The foot will pronate to compensate for the knock-kneed position of the legs and the amount of pronation will be greater than normal, or over-pronation.
Over-pronation can also be a normal amount of motion, but motion that happens for too long. By the time the foot is preparing for the push-off phase, the time when the heel lifts and you move onto your toes, pronation should have stopped and even reversed. Thus, if your foot is pronating into the push-off phase, you over-pronate.
Dr. Nick Brown
Dr. Brown is a postdoctoral researcher in the Department of Biomedical Engineering at The University of Texas.
