We’ve all seen the commercials of long-distance runners who seem to be gliding blissfully on cushions of air, their toned legs impervious to the constant pounding of their feet on unforgiving concrete and asphalt. Their secret? Special insoles in their shoes or orthotics that absorb the punishment so their bodies don’t have to.
But a new review of nearly two dozen studies and clinical trials found no evidence these shock-absorbing insoles — designed to soften the impact on feet — actually prevent injuries or stress fractures. Foot orthotics, intended to even out pressure on the foot, do provide some benefits.
Researchers at La Trobe University in Melbourne, Australia studied data from 11 clinical trials on foot orthotics and another seven studies of shock-absorbing insoles. In results published in the British Journal of Sports Medicine, their analysis showed that the shock-absorbing insoles didn’t reduce the risk of any type of injury, including tendon or muscle problems, knee pain or back troubles.
The silver lining for your sore feet? Foot orthotics were effective for preventing overall injuries and were associated with a 41 percent lower risk of stress fracture in the legs or feet. But they were not effective in preventing soft-tissue injuries.
The researchers noted the quality of the various trials varied greatly. They suggested more studies could help improve the accuracy of the manufacturers’ estimates of how much their products reduce the risk of trouble.
But until then, when it comes to believing claims about near-miracle insoles, runners should tread lightly.