What It Is: These smartphone-compatible running socks are embedded with tiny pressure sensors and promise to help you improve your running form.
Why We Like It: In the wake of the minimalism running movement, most runners want to believe that they have a forefoot strike (landing on the ground with the ball of their foot first), when the reality is the overwhelming majority of us are heel strikers. While the science still isn’t clear on whether one footstrike is better at preventing injury than another, most folks generally believe that landing closer to your center of mass results in less stress (and risk for injury), and can help you run faster. But how does one know if they’re doing so?
The new Sensoria Smart Sock uses three small fabric sensors stitched into the sole of each sock (one under the heel and two under the ball) to transmit pressure when you stand to a cuff that you wear around your ankle. You don’t feel the sensors at all, but you can see that they’re working when you pair the device to your smartphone — each lights up with greater intensity as you apply more weight. When you run, the device tracks how frequently you’re landing on each sensor, as well as counts the number of steps you take and how long your foot remains on the ground (ground contact time, measured in milliseconds, can help indicate whether you’re over-striding). The app also does basic GPS distance logging and can show your pace. At the end of a workout, it shows you the percentage of your most frequent landing — it said we landed on the ball of our foot 88 percent of the time during a nine-mile run.
Nitpick: The sensors seemed to have a hard time discerning footstike accurately when we landed “midfoot” — making contact with heel and ball nearly instantaneously. Through many high-speed videos and photos, we know that we consistently land heel first, even if just briefly, but the app told us we mostly landed on the ball of our foot. When we forced a landing toward either extreme, however, the sensors more reliably picked up our footstrike. In any case, we found the cuff quite uncomfortable after just five or six miles; it rubs our tibialis anterior tendon — the tendon along the front of the ankle that stiffens when you lift your toes. We took the cuff off mid-run and discovered a sore red spot afterward.