As you walk, your foot is constantly changing shape, and it needs the shoe you’re wearing to do the same.
When walking barefoot, even more muscles are active: first the heel takes the body’s weight, then the load moves in a curve toward the base of the little toe and from there toward the big toe. As the heel lifts, the foot bends at the ball of the foot during push-off.
Roomy, flexible shoes with a thin sole allow your feet to bend naturally in all directions.
