Gabe Mirkin, M.D.
A study in the journal from the American College of Sports Medicine shows that the runners who are most likely to become injured have feet that hit the ground with the greatest force and roll the least after hitting the ground. If your feet hit the ground flat-footed, the shock could break your bones. Instead, people land on the outside bottom of their heels, then their feet roll inward from the outside bottom on the fifth toe side toward the big toe.
To protect your muscles and bones, your foot rolls inward from the fifth toe toward the big toe. To prevent injuries, shorten your stride and use firm inserts that fit underneath your feet and fill the space underneath your arch. To hold your feet on the insert, use running shoes that have a firm counter surrounding your heel that extends forward to your arch and a saddle that runs from the sole to your laces. To reduce foot s force, take shorter strides. Trying to take extend your stride slows your down by wasting energy.