Studying Anatomy and Biomechanics in my free time, along with and working in a running specialty store and having a degree in Kinesiology, my mind is constantly wondering about hot running topics. With the huge boom in running over the past couple of decades, shoe companies have been trying to construct shoes for not only the masses but also the individual runner. While this is a great thing, it has only turned into a marketing strategy.
A lot of us runners (myself included) have gone into a running speciality store in the past decade and have been told something close to "You're an Overpronator, we need to have you in a support shoe" as if the employee was diagnosing us with some fatal disease and that our running goals were doomed unless we purchased one of these magical "support shoes" or "motion control shoes" to help our pronation problem.
This is all fine and dandy, except there are 2 problems:
1- PRONATION IS NOT A PROBLEM
Pronation can simply be defined as the inward rolling (eversion) of the foot during foot landing. It just so happens, pronation is a good thing! Pronation causes your foot to "unlock", making it less rigid, and serves as a natural shock absorber by spreading out the force. As your foot is loaded, it's natural for your arch to drop, aiding in the pronation process. If your foot is very rigid and doesn't pronate, you may have been called a "Supinator" at your local running store. If you're a supinator and your foot isn't pronating, this does increase the risk of stress fractures and shin splints since you're not dissipating all the shock and impact from running, and it's traveling up your leg. One quick fix is to lightly massage the bottom of your foot for a couple of minutes before you head out the door to go run. You can do this by rolling it on a small ball, or convince someone that it will help decrease the chance of getting a stress fracture and BOOM! You get a free massage! Now back to Pronation...
Shoe companies see this inward motion of the foot and associate it with higher injury rates, saying that overpronating causes rotation of your lower leg, which puts stress on your joints leading to more injuries. As mentioned earlier, they then try to prevent the injuries by selling you a support shoe. The unique thing about support shoes is they consist of different density materials on the inside of the shoe by your arch, which supposedly limits pronation, which they claim will limit injury. The truth is, there is no correlation with the degree of pronation and injury rates. One study Nigg et al. (2000) showed that foot and ankle movement did not predict injuries in a large group of runners. This leads us to our second problem:
2- SUPPORT SHOES DON'T DO WHAT THEY CLAIM
The main selling point of support and motion control shoes is that they have denser foam on the medial side of the shoe which will prevent you from pronating and will keep you properly aligned, lowering injury rates. But if these runners that are classified as overpronators are now running in a support shoe, why are 65% of runners still getting injured every year? That's the same amount of runners who were getting injured decades ago before support shoes even existed. Also, when looking at a runner's gait cycle, it's been observed that the point of maximum pronation occurs after mid-stance, once the heel has left the ground. This means that the medial posting that is supposed to give us support and prevent the foot from pronating isn't even in contact with the ground anymore. So what good is that support mechanism even doing when it's flying through the air? Not much...
One study showed that motion control and support shoes did not reduce peak eversion (pronation) levels, and they didn't change the concentration of pressure (Dixon, 2007).
So, shoes do not stop your feet from pronating, and they don't control the position of your foot because that job belongs to your muscles.
Every runner knows that running on soft surfaces is much better for your bones and joints, rather than harder surfaces. The other benefit of these types of surfaces is it introduces more variability to your feet so they can become stronger. When you're running on grass and trails, you're practicing different foot and ankle stabilization patterns that will strengthen those muscles that don't get worked as much when running on hard flat surfaces. Don't fall into the common trap thinking that the shoe will stabilize your arch when in reality your muscles will! So give them a good workout and run on different surfaces.
SO WHAT FREAKING SHOES SHOULD I RUN IN??????
I'm not saying support shoes should be avoided at all costs. I'm just saying the idea that a shoe can prevent injury is flawed. In the running specialty store I work in, we have gotten away from using the word pronation because it's a word that has struck fear into millions of runners. New studies suggest that the shoe that will be the least likely to cause injuries for you is the shoe that is the most comfortable. After all this reading I know it's a very vanilla answer to say "Just go with what feels comfortable", but it is the best answer science has given us at this current moment. So instead of obsessing over getting in the scientifically right shoe for you based on what someone is saying, try out several shoes and find the shoe that works best for you, regardless if it's neutral, support, or motion control. The old theory that a runner who has more inward motion (pronation) needs to be in a support shoe while other runners who have a more rigid foot (supination) needs to be in a neutral/cushioned shoe is outdated. The person at the running shoe store is likely very knowledgeable and can certainly help guide you to the path of some shoes that might work better for you, but your body is a very intelligent organism, so listen to it, not the "shoe expert" who is trying to sell a pair of shoes.
So, shoes do not stop your feet from pronating, Injury rates among runners have stayed the same since the introduction of support shoes, and shoes don't control the position of your foot because that job belongs to your muscles. To find the shoe that works for you, be open minded and try out a couple of different shoes over the months until you find what feels the most comfortable and stop blaming the shoes for causing your injury because it is more likely caused by a training error or muscular imbalance.