your ankle contains a shock absorber and propulsion engine needed to sustain the pressure caused by lifting and doing high impact activities like running. That is why when you run barefoot, you have less chance of a foot injury. When your sole makes contact with the ground, it automatically communicates with your ankle on how much shock absorption to give it and where to place your foot. If your sole, however is blocked from making contact, the ankle does not know how to read that message. That is why when you land on an uneven surface with your shoe, you will sometimes cause a sprain in your ankle. On the other hand, when you step on an uneven surface barefoot, your ankle immediately picks up the signals sent by the neurons of your foot and there is less of a chance of spraining it.