Foot supination, a.k.a. underpronation, occurs when your weight rolls onto the outer edges of your feet as you land each foot strike on the run.
In a healthy stride, your foot should roll inward a bit (that’s known as pronation) so that your weight is on the ball of your foot. This way, you can push off the big toe. Runners who habitually supinate place extra stress on the outer side of the foot, which can trigger issues, such as ankle injuries.
Those with high foot arches are more likely to supinate, along with runners with muscle weakness in their calves or ankles. Finding the right running shoes can help you avoid any complications with foot supination, as can certain exercises.
To help you recognize if you have foot supination, we spoke with experts about the telltale signs. Plus, we have advice for alleviating any potentially harmful effects of this degree of pronation.
How to Know if You’re a Foot Supinator
1. Your shoes get worn out on one side
When someone who supinates runs, the outside edge of their foot hits the ground first, Steven Weinfeld, M.D., chief of foot and ankle surgery at The Mount Sinai Hospital in New York City tells Runner’s World. Because the foot does not sufficiently roll inward after landing, the force of impact remains concentrated on the outside of the foot. If your running shoes wear out quickly and unevenly with more breakdown on the outer side of the shoe, it’s likely you supinate.
In turn, this uneven wear of the shoe can make supination even worse because it decreases the shock absorption of your shoe when you land. Also, it reinforces a gait where the impact of landing isn’t distributed evenly.
To check if your shoes have uneven wear, place them on a flat surface. If they tilt outward, supination is likely in play.
2. Bone fractures and ankle sprains are common
Because supinators place more pressure on the outer part of their feet, stress fractures on the fourth and/or fifth metatarsal—the large bones in the middle of your foot connected to your fourth toe and pinky toe—may have you heading to the podiatrist more often than you’d like. That’s because those tiny toes are doing most of the work when you push off while running.
Supinators are also more likely to experience stress fractures on the fibula, which is the outside bone of your lower leg.
“A fibula fracture is not very common, but supinators may be more likely to stress this area,” Marci Goolsby, M.D., medical director of the Women’s Sports Medicine Center at Hospital for Special Surgery in New York City tells Runner’s World.
In addition to triggering stress fractures, this extra pressure caused by supination can also diminish ankle stability and increase the likelihood of rolling or spraining an ankle, Weinfeld says.
3. You’re stopped cold by shin splints
A supinated foot is less shock absorbent, Weinfeld says, and running on it repeatedly may, over time, cause lower leg pain commonly known as shin splints.
Shin splints occur below the knee either on the front outside part of the leg (anterior shin splints) or the inside of the leg (medial shin splints). Because supinators run with the majority of their weight on the outer part of their feet, they are more likely to experience anterior shin splints. If you regularly dealing with shin splints, there are a few ways to deal with them, including exercises.
4. Your calf and achilles are super tight
This one is a bit of a “chicken and egg,” dilemma, Goolsby says. People with tight Achilles tendons and calf muscles tend to be supinators because the extra stress placed on the outside of your foot can radiate upward and contract your other muscles. Conversely, tight Achilles tendons and calf muscles may cause (or worsen) supination.
If you feel chronically tight in one or both of these spots, you may be a supinator—or at risk for becoming one. Again, there are many ways to support your Achilles tendon and calves with exercise and recovery.
5. You have stabbing plantar fasciitis pain
Supination can create extra strain on the ligament connecting your heel and toes, known as the plantar fascia. The result? Plantar fasciitis, a painful condition characterized by a sharp stab or deep ache in the middle of the heel or along the arch of the foot.
Plantar fasciitis is a common ailment for runners and can be caused by factors other than supination. Still, it’s worth asking your doc if there is a connection.
How to Address Foot Supination
It’s hard for the average person to know that supination is the underlying cause of any of the aforementioned issues, Weinfeld says.
“It often takes a physical therapist, podiatrist, or other doctor to study the foot alignment and diagnose the issue,” he says. A doc or running shoe expert can watch you walk or run on the groud or a treadmill to check your gait.
“Flexible” supinated feet are more easy to correct, whereas supinated feet that are “rigid” are much harder to fix, Weinfeld says. The flexibility or rigidity of your supination may be genetic—or it may be a factor of your age.
“People can start out with flexible supination that, as they age and their bones become more arthritic, turns into rigid supination,” Weinfeld says.
Once your supination has been diagnosed, there are several things you can do to alleviate the condition and its related ailments:
1. Incorporate strength training
“Perhaps the number-one thing you can do to alleviate the negative effects of supination is strength train,” Goolsby says. “It’s important to be strong all the way through your kinetic chain.”
She recommends focusing on glute and hip-strengthening exercises that will bring greater stability to your ankle and feet, which are often the first areas stressed by supination.
2. Get the correct footwear
Replace your running shoes before they are significantly worn on the outer side, Weinfeld says. You may also consider visiting a specialty shoe store to get some advice. You’ll typically want to be in more cushioned or neutral shoes that allow your feet to pronate more. Many of the big brand names, like Hoka, Nike, Asics, and Saucony have supinator-friendly shoes to get you going.
Best Shoes for Supinators
Brooks Glycerin 20
Brooks’s Glycerin is its most cushioned trainer. The newest version has a DNA Loft v3 midsole which translates to a responsive ride.
Altra Via Olympus
The zero-drop Via Olympus is cushioned to the max. The shoe’s last has an accommodating fit for runners with wide feet.
Hoka Clifton 9
The Clifton 9—the lightest version of the trainer—is extremely versatile. Our testers logged easy runs and hard tempos in this chameleon.
Saucony Triumph 21
The Triumph 21 has a redesigned lacing system for a more secure fit. Upping the comfort factor is a plush heel collar and tongue.
3. Consider orthotics
In general, orthotics are trickier to build for underpronators versus overpronators. “But sometimes there is a role for inserts,” Goolsby says. “The insert would be less corrective, but would focus more on providing cushioning and a comfortable surface area for your foot.” You can buy supination-friendly orthotics at a specialty shoe store, but a doctor will likely recommend custom-built ones.
4. Adopt a stretching routine
Stretching before and after you run is something every person should do, but it’s especially important for supinators. Regularly stretching your calves, Achilles, shins, and ankles can help alleviate tension that may be causing or worsening your supination.
Jenny is a Boulder, Colorado-based health and fitness journalist. She’s been freelancing for Runner’s World since 2015 and especially loves to write human interest profiles, in-depth service pieces and stories that explore the intersection of exercise and mental health. Her work has also been published by SELF, Men’s Journal, and Condé Nast Traveler, among other outlets. When she’s not running or writing, Jenny enjoys coaching youth swimming, rereading Harry Potter, and buying too many houseplants.
