Flat feet, high arches, over pronation, supination, and heel striking, as runners we hear many recommendations on what type of shoe we need based upon our foot type, but what does the research say?
Thirty-five to fifty-six percent of runners are injured each year. The type of shoe you run in, has little impact on the frequency of injuries. That’s right my fellow runners, how often you are injured doesn’t have much if anything to do with the type of shoes you run in.
A research study done in North Carolina with 700 runners, all of which had been running for more than ten years, and who ran approximately 20 miles a week showed no difference in injury rate regardless of wearing stability shoes, motion control shoes, or cushion shoes, Gross (2011). There was also no difference in injury rate based upon heel, mid-foot, and forefoot strikers.
Everyone thinks that running injuries are caused by impact forces and pronation issues. Pronation is looked at as being a problem because the extra rotation of the foot causes more rotation in the ankle, muscles and tendons. There have been a few studies, which show that there is no difference in injury rate for marathon runners who over pronate Wen et al. (1997), Wen et al. (1998), and Nigg et al. (2000).
There have been studies on whether or not motion control shoes actually stop pronation as well. The resounding answer is No they do not change the way the foot and lower leg muscles and tendons move Stacoff (2001), Bulter (2007), and Dixon (2007).
All right so pronation isn’t the culprit we thought it was, what about impact forces? The running community has long believed that the greater the force when you hit the ground the more likely you are to suffer from injuries because of the increased stress to the foot and leg.
Studies on whether or not cushioned shoes actually reduce internal and external impact forces show that there is little to no reduction in the forces, Nigg (2000).
Another study, Nigg (1997), showed that there is not a difference in chronic injuries rate between high impact runners and low impact runners. Nor does the type of surface you run on make a difference in injury rate. To make this even more confounding, impact forces increase bone density!
Why doesn’t impact forces have an impact on frequency of injury? Because your body adapts to the surface it is coming into contact with Nigg (2000) and O’Flynn (1996). The idea is that when you impact the ground, your foot sends a signal to your brain saying how hard the surface is and your body adjusts using your leg joints (which act like a spring: hip, knee, and ankle). There is also research showing that choosing your shoes based upon your arch height does not reduce injuries either Knapik (2009)
When you have a cushioned shoe, your body just takes the extra cushion into account and remains more stiff through your leg. Regardless of the amount of cushion under your foot, you impact the ground with the same force because of the sensory feedback from foot to brain.
IF shoes don’t help prevent injuries, what does? Training properly by increasing miles slowly, no more than 10% a week. Misalignment of joints, think about seeing a chiropractor. Tight soft tissues, use your foam roller.
Okay, so which shoes should I buy? The ones that feel the most comfortable. Try on different types of shoes and go for a run around the block or on the treadmill for a quarter mile. If they feel good, buy them.