Whether you run in soft, cushy shoes that feel like pillows tied to your feet or shoes with a harder, stiffer midsole, you're still at the same risk of injury, according to a new study published in the British Journal of Sports Medicine.

Researchers from the Sports Medicine Research Laboratory in Luxembourg hypothesized that runners training on a hard midsole had a higher risk of running-related injuries than runners logging miles in soft running shoes. 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 percent stiffer in the heel.

Five months later, researchers found that the runners who wore the cushioned shoes had just as many injuries as the group wearing the harder shoes. Soft, cushy shoes didn't even protect heavier runners, who are often told to buy shoes with extra cushioning.

"Midsole hardness of modern cushioned running shoes did not influence running-related injury risk," researchers wrote.

What were indicators of injury, according to the researcher's model, were the subject's body mass index, a history of injury, and perceived exertion rate. What seemed to protect runners from injury were a history of regular running and involvement in other sports on a weekly basis.