If you’re counting on your insoles to save you from exercise-related injury, you might want to rethink your strategy. Despite all the marketing gimmicks, there’s actually no evidence to suggest that shock-absorbing aftermarket insoles actually do anything to reduce the incidence of foot and leg injuries.
A lot of negative things can happen to you if you’re a runner. You can incur muscle, bone and tendon damage, get stress fractures and also come down with various repetitive stress injuries.
A new meta-analysis of available studies on the subject was recently published in the British Journal of Sports Medicine. Its verdict on those expensive, sciencey-seeming insoles? Thumbs down.
The analysis did, however, have some good things to say about orthotics. However, the data isn’t strong enough to make a definitive statement one way or the other.
Most commonly, people who exercise regularly will get medial tibial stress syndrome, Achilles tendon dysfunction and plantar fasciitis, as well as knee pain. Foot orthotics, which are designed to manage pressure and correct gait, are much more effective in warding off injury than shock absorbing inserts. They are also effective in treating already-existing problems.
The meta-analysis pools the data of eleven clinical trials regarding foot orthotics and seven regarding shock-absorbing insoles. They found that foot orthotics reduce the general incidence of injury by 28%, and reduce the likelihood of stress fracture in the legs and feet by an impressive 41%. They were not, however, effective in preventing tendon and muscle injury, or knee or back pain.
Shock-absorbing insoles, by comparison, had no detectable effect on any injury metric. One of the studies examined even demonstrated that they increase risk of injury.
The study’s authors urge caution in taking their results at face value, though. They call for further research, claiming that the research methodologies of the studies they analyzed varied in acceptability.
There is also some concern about the data, considering that they were gathered largely from insole use in military personnel. People in the military have much more rigorous exercise regimens than pretty much any civilian, rendering the datasets somewhat specious. They also exercise in boots.
Until thorough research is conducted, it’s hard to say that shock-absorbing insoles are unequivocally not effective. But the early results do seem to suggest as much.