Why Traction and Cushioning Matter in Every Step

Most slips and small aches in the knee and ankle come not from strength or fitness but from a shoe that does not suit the ground you walk on. Traction comes from rubber and its pattern. A fine, tight pattern suits smooth floors in gyms and malls because more of it touches the ground. A deep, widely spaced pattern suits dirt, gravel and sand because it digs in and sheds mud instead of clogging. Cushioning spreads the force of each landing over a longer moment, so the full shock never reaches the ankle and knee. Someone running on tarmac needs more cushioning at the heel; someone lifting weights needs less, and a firmer sole, because soft foam wobbles under load. Check the soles of your shoes every few months. If the pattern has worn smooth at the heel, or deep creases have appeared in the foam along the side, the shoe has done its job and it is time for a new pair.