"One patient was breaking in a pair of toning sneakers, and less than 45 minutes after putting them on felt her ankle turn and a bone break," said Aritzur.
Surgeons say they are not surprised. Toning shoes are intentionally designed to create instability. They could be difficult for elderly people or anyone with balance issues.
Even younger people are complaining about problems with shoes like Skechers Shape-Ups. The instructions tell people to wear the shoes for short periods of time at first to allow the body time to adjust.
Consumer Reports says the health benefits of toning shoes are uncertain but the risk of injury is very real.
New injury statistics from the Consumer Product Safety Commission show that even younger people in good physical shape have had problems, some of them serious.