Research Ends Shoe Sole Debate

Still trying to decide if hard or soft soles on their shoes protect runners from injury? If so, give up because a new study published in the British Journal of Sports Medicine has found that the hardness of the sole makes no difference.

According to Stephen Kasica, writing for Outside, researchers at the Sports Medicine Research Laboratory in Luxembourg hypothesized that runners training on a hard midsole had a higher risk of running-related injuries than did runners running in soft shoes. To test their assumption they monitored 247 runners wearing 12mm-drop trainers from “a renowned sports equipment manufacturer.” Some subjects wore cushioned shoes, and others wore a midsole that was 15% stiffer in the heel.

When they examined the runners five months later, the researchers found that the runners who wore the cushioned shoes had just as many injuries as did the group wearing the harder shoes. They also found that soft shoes did not protect the heavier runners from injury.

“Midsole hardness of modern cushioned running shoes did not influence running-related injury risk, ” researchers wrote. More relevant to the prediction of injury was the runner’s body mass index, his or her history of injury, rate of exertion, history of regular running and involvement in other sports on a regular basis.