A recent study of the Harvard Cross Country team examines how and why runners sustain ankle and foot injuries.
The study, published in Medicine & Science in Sports & Exercise, analyzed four years worth of statistics about Harvard runners. Researchers found a correlation between how a person runs and the likelihood of their getting injured.
Most runners initially strike the ground with the heel of their foot, rather than the ball. This is due, in part, to the cushioned running shoes that we use. However, some hypothesize that running on the balls of your feet is more natural, as some evidence suggests that early hunter gatherers ran this way.
The study did not find that running on the balls of your feet was a guaranteed way to prevent running injuries. But, it did find that those who run on their heels are more likely to sustain ankle & foot injuries for some reason.
69 percent of the runners in the study were heel runners. The other 31 were ball runners. The heel runners were twice as likely to injure themselves enough to miss two or more days of training.
Dr. Silverman Comments
“The running injuries in this study are all due to overuse,” says Minneapolis Orthopedic Surgeon, Dr. Lance Silverman. “An overuse injury occurs when tissue breakdown exceeds tissue build up. Tissues such as bones, ligaments, and tendons break down when the muscles that protect them are fatigued.”
When running, a person places 3-4 times their body weight on each foot that strikes the ground. The foot, leg, and core muscles absorb the impact of each step (this is known as Ground Reaction Force). When muscles tire, they expose the tissues to supra-physiologic stress. This leads to stress fractures, chronic ligament sprains, and tendon strains.
Running in shoes is distinctly different from running barefoot. The heel counter (back of the shoe), the arch, and the cushioned bottom of the heel limit the stress imparted to the foot. In fact, shoes and arch supports actually weaken the foot muscles.
“The answer to preventing injury lies in cross-training and shoe wear,” says Dr. Silverman. “Finding shoes that support less, training foot support muscles more, and using non-impact exercise to vary the training schedule will prevent injury.”
Related Sources:
NYTimes.com
