Let’s talk about our feet today. That’s right, our feet. We runners think a lot about our feet, since the littlest aches and pains can turn a good run into a miserable, am-I-done-yet experience. Up to 80% of all runners experience some degree of injury each year, and a majority of the most common running injuries either affect the feet (plantar fasciitis, Achilles tendonitis) or are caused by problems with the feet (such as IT band syndrome or runner’s knee).
What is it about feet that can cause so much injury? Since feet provide the base for propulsion, landing, and shock absorption in running, anything wrong with the feet will affect the muscles and joints used in running and our overall biomechanics.
Common running knowledge upholds that overpronation and underpronation (supination) are some of the major causes of running injury. However, some research indicates that pronation and supination are not the direct causes of injury and that foot type ultimately does not matter. Whether that hypothesis is true or not, overpronation and underpronation are still something which all runners should know about, as it can matter when it comes to improving your running form, picking out the right shoes, and preventing future injury.
How you pronate your feet matters for two significant reasons: picking out the right shoes for you and understanding your risk of potential injury. These two are interconnected, of course, as running in the wrong pair of shoes can increase your chances of getting injured.
Overpronation vs. Underpronation
How do you know if you pronate or supinate? Look at your feet and how they land. If you land with most of your weight into the insides of your feet and your foot rolls in (so your ankle points out), you likely overpronate. If, like me, you land on the outside of your foot and point your ankle in, you underpronate (supinate). If you don’t do either, you are likely a genetic miracle with perfect feet.
Typically, overpronators tend to have a flatter arch, while supinators will likely have a high arch. How do you know if your feet are highly arched? Simply look at how your feet imprint on the bathroom rug or a towel when wet. If most of your foot shows up in your footprint, you have flat feet. If you see your toes, ball of your foot, and then just a small outside line connecting to your heel, you have high arches. If a bit of your foot does not appear in your footprint, you have a moderate arch. However, arch height is not a completely accurate indicator of overpronation or underpronation. Some people with high arches overpronate and vice versa. Arch rigidity also factors into pronation; the more rigid your arch, the more likely you are to supinate, while the less rigid your arch, the more likely you are to overpronate.
Some degree of pronation is normal and essential for shock absorption. With normal pronation, you push off evenly with your entire foot. Overpronation occurs when your foot rolls in more than it ideally should. The cause of this is often ankle instability, as overpronation puts a significant amount more stress on the inside of the ankle. Overpronation can lead to injury through poor shock absorption and improper running form, as well as putting you at risk for runner’s knee, shin splints, plantar fasciitis, and Achilles tendonitis.
Supination happens when your foot does not pronate enough. Supination thus concentrates most of the load onto a smaller portion of your feet and often supinators do not push off enough with their big toe (as you should be doing). If you supinate, you likely notice this in even your normal walking stride. I, for example, will actually stand on the outside of my feet with my arches and big toes off the ground (I’m constantly working on this). The uneven distribution to the outside of the feet puts supinators at a higher risk for IT band syndrome, plantar fasciitis, and Achilles tendonitis.
How to Fix Overpronation and Underpronation
First and foremost, as with anything in running, be careful not to to do too much too soon as that can lead to injury! Rather than immediately forcing your feet into a different position, focus on choosing comfortable shoes for your foot type and making small modifications to how you run to gradually improve your biomechanics, as I’ll discuss further below.
When it comes to running shoes, it is highly recommended to get a gait analysis, which many running stores offer for free. A running store employee will watch you run, determine your degree of pronation (along with any other gait issues) and recommend the best shoe for you. For many runners with mild overpronation, a good running shoe will correct this. Runners with severe overpronation may need a more cushioned stability shoe, while runners with underpronation will likely do better in a more neutral or lightweight shoe. Some overpronators do find that neutral shoes work for them; what feels most comfortable to you and keeps you injury-free matters most of all when it comes to running shoes. (Want to know more about pronation, injury, and running shoes? Watch this video from Dr. Jordan Metzl over at Runner’s World.)
If your overpronation or underpronation is significant enough to cause discomfort, injury, or poor running form, improving your running form and strengthening your feet and ankles will also help you prevent injury and run better. One of the easiest and most effective improvements you can make to your form is to take shorter and quicker steps as you run. This will prevent overstriding, which can exacerbate any biomechanical problems due to overpronation or supination. Strengthening your feet (especially your big toe) and your ankles through calf raises, barefoot yoga, single leg hops, and plantar and dorsal flexions with a resistance band will also alleviate any major problems from overpronation and underpronation.
And now, since you listened to me ramble about technical running science-y stuff for the second day in a row, here’s a picture of Charlie napping to make up for it.
Questions of the Day:
Do you overpronate or underpronate?
What running shoes work best for you?
Do you just want to take a nap like Charlie? —-> yes.
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