As a physical therapist who has treated runners for 13 years, THIS is what I tell my runners about running shoes (some of these may shock you)!
1. Heel To Toe Drop: This is the height difference in mm between the heel and the toe of the shoe. Most running shoes have a heel that is significantly higher than the toe, creating a high heel scenario. Studies have shown that elevated heels not only compromise foot proprioception (the brain’s ability to know where the foot is in space) but also disrupt the normal muscle firing patterns in runners. The optimal heel to drop to preserve foot biomechanics is 0. That’s right! A completely flat shoe is where it’s at!
2. Stack Height: This is the amount of shoe material that separates your foot from the road. Most modern shoes boast revolutionary materials to support and cushion the foot. In theory, this is a good thing. Unfortunately, all of this support and cushion does 2 things: 1. The support allows the muscles of your foot to turn off, instead relying on the shoe for support. Over time, this will weaken your foot muscles and increase your risk of injury. 2. The increased cushion will dull your foot proprioception, making it harder for your brain to fire the correct foot stabilizing muscles at the right time, again putting you at increased risk of injury. I usually recommend a stack height of 24 mm or less.
3. Toe Box: Your foot is a leaver that works to propel you forward as you run or walk. A wider foot means more leverage, therefore more stability. Most running shoes taper aggressively through the arch and toes. This constricts the foot and compromises proprioception. A wider toe box allows the toes to splay which
improves leverage and results in more control- which is exactly what we want! A good test to see if a shoe has an adequate toe box is to take out the insole, put it on the floor, and stand on it. If you see any part of your foot hanging off the insole, this is not a good fit for you. Bonus points if you find a foot shaped toe box as is found in Altras.
Of course there are exceptions to these rules, as all feet are different, but this framework should provide you with a place to start in your journey to find your favorite running shoe!
