Has everyone seen the alternative looking Vibram Five-fingers? It’s a shoe designed to mimic barefoot running while protecting your feet from lacerations and infections caused by under-foot debris. These shoes have gained popularity since the surge of barefoot running. So why are people choosing to run barefoot, when the technology of running footwear is so advanced these days, that they pretty much run for you?
The argument seems to be that barefoot running softens the impact on the joints and enhances muscular coordination and balance, thereby minimizing running injuries. The typical gait cycle during running or walking involves heel strike, midfoot contact, and push-off from the balls of the foot, or forefoot. With barefoot running and without the cushioning of a well constructed running shoe, heel strike is uncomfortable, so a midfoot or forefoot strike is adopted.
During a forefoot strike, less of the body comes to a dead stop at the moment of impact, so there is less force involved in the collision. In addition, the structure of the foot and lower leg is very efficient at absorbing the shock of landing and turning the energy of the fall into forward motion, through the springing action of the foot’s natural arch. This dissipates the force of the foot landing over a longer period of time and slows the rate that ground forces travel up to the rest of the body (knee, hip, pelvis, spine, and head). Landing on the fore or mid foot, however, requires an eccentric or lengthening load on the calf muscles and the Achilles tendon to keep the heel from slapping down on the ground. A heel strike is basically a collision between the heel and the ground without the benefit of the mid and fore foot structures minimizing and slowing the shock. This shock wave is a potential source of injury, but few scientific studies have yet been published to conclusively determine if transitioning to a barefoot style of running would stave off injury.
So does this mean we should all abandon our shoes? Probably not. Shoes are comfortable, and running shoes in particular do absorb a substantial amount of ground force during the gait cycle. A good compromise would be to try running barefoot-style in running shoes as part of your training program, although this is easier to do with shoes that lack a built-up heel. But there may be some benefit to runners in spending some time barefoot to strengthen the muscles and running-related tissues, and to re-awaken our neural balance mechanisms.