Proprioception is defined as the perception or sensing of your limbs in space (orientation) during movement of the body. Specifically in running, proprioception allows your mind to learn, with each step, from the effect of each movement and then adjust your limbs accordingly for future movements. Proprioception comes from the Latin word proprius, meaning “one’s own” and perception. It’s proprioception that allows the brain to adjust the posture and gait to uneven ground, or limp when the blister on the big toe begins to hurt, The foot automatically senses information about ground contact with each and every step. With this data, your brain responds accordingly. That blister might force you to adjust your gait to a limp to alleviate the foot pain. It’s also why the tiniest pebble lodged inside a shoe or sock will cause discomfort until you stop, remove the shoe or sock, and get rid of the nuisance once and for all. As the foot’s nerve endings send important information—regarding its movement, tension, pressure—to the spinal cord and brain, it allows the whole body to respond to foot-sense.
But many types of ill-fitting running shoes, and those that are over-supported, too much cushioning, and rigid tread and heel, can put stress on the foot’s delicate structures, including muscles, bones, ligaments, joints, and even the skin. In addition, shoes that produce a noticeable height difference between the heel and front of the foot can be an unnatural stressor, especially on the knees. Going barefoot means that there is the same height front and back, or “zero drop,” but a shoe with a thicker heel causes the front of the foot to drop further down. Many conventional running shoes have a drop over 12 millimeters, or half-inch to an inch. Some have much more.
So don’t be seduced by the shock-absorbing material of the shoe’s sole. The thicker the tread, the harder it is for the brain and foot to properly communicate with the body. In other words, the soles of the feet can’t stay in “contact” with the ground. You want that earth-to-foot rapport. While an over-developed shoe bottom might be protecting your foot from rocks and tree roots if you are running on a trail, there’s still a lack of foot-sense, which, in turn, restricts proprioception This can throw off a stride and cause further biomechanical stress, because the brain is also less aware of where the foot is landing—and how to make minute adjustments. –by Dr. Phil Maffetone
by Dr. Phil Maffetone