Your pillowy, comfy running shoes could be putting you at an increased risk for injury, according to new research from Ithaca College. When you consistently wear padded running shoes, the researchers found the larger or "extrinsic" muscles in your feet do all the work of sending sensory messages to the motor systems in your body. Meanwhile, the "intrinsic," or little muscles in your feet are ignored. Over time, in other words, you're training them to do nothing. What results is that you rely more heavily on those extrinsic muscles, and they in turn get overworked and tend to break down faster, which can lead to ankle sprain, shin splints, plantar fasciitis, and even back pain.
"The less cushion you have in terms of a shoe, the more you're able to sense what's going on between the foot and the ground," says Ithaca professor Patrick McKeon. In other words, it should help your feet process the absorption and propulsion demands as you run.
McKeon likens the concept to our understanding of how strong abdominal core muscles create a sort of girdle of support for the spine that improves posture and lessens your risk for back injuries, because no abdominal muscle group is tasked with doing the work of another. Similarly, with extra foot muscles (the intrinsic ones) working for you, your risk for injury is lower.
Targeting those intrinsic muscles requires exercise in bare feet. But does this mean you should shun your shoes and run barefoot? Not at all. "I'm by no means advocating we should throw our shoes away," says McKeon. He offers an example to illustrate the dangers of throwing oneself into the barefoot running trend: A guy who wears a weight belt at work but never exercises without one has a good chance of injuring himself if he suddenly goes to the gym and starts lifting heavy weights, he says.
People got injured not because barefoot running is a bad idea, but because they leapt headlong into it without the careful progression needed to help the foot adapt to the new demands of shoeless running, which McKeon says is crucial before attempting it.
"Going barefoot around the house is a good start to get a person used to integrating sensory information from the foot," he says, although it won't be super-effective in building up what McKeon calls the "foot core" muscles. That's why he recommends a couple of easy exercises to work your foot (see below). The message McKeon and his colleagues most want to get across: "We need to think about how we can strengthen the foot to meet its demands, regardless of what type of shoe you're wearing."
The Foot Core Workout
- Stand barefoot and put a quarter under the ball of each foot, then do a heel raise. If you have a weak foot core, you'll roll out to your pinky toes; this tells you that you don't have good control of your foot core muscles.
- Raise heels slightly, enough to feel the pressure shift to the quarters or the ball of each foot.
- Raise heels as high as you can go without rolling out, and hold for 10 seconds at a time. Start with 3–5 sets of 10 reps of 10-second holds.