Plantar fasciitis is a type of injury that affects a long ligament in the bottom of your foot, causing pain in your heel, Kuizinas says. It happens when the ligament gets overworked because of weak foot muscles, poor foot movements or injury. To help with this condition, Kuizinas recommends sandals that are wide at the toes and foot-shaped, as well as have a flexible sole, straps that hold your feet securely, and moderate cushioning. To prevent injury when transitioning from winter shoes to summer and spring sandals, Kuizinas recommends simple foot exercises: Short foot. Short foot is a technique where you contract the bottom of your foot by reducing the arch's height. Place the ball of your foot on the ground and lift your toes. Then, gently press your toes back down while keeping them flat on the ground. Rolling. To perform this exercise, you’ll need a small, firm ball like a tennis ball. Place the ball just in front of your heel and roll it back and forth along your arch using your body weight. Use as much pressure as you can handle comfortably, Kuizians explains. This technique helps to release tight muscles on the soles of your feet and improves your tissue tolerance. Calf raises. According to Kuizians, calf raises are a great exercise for strengthening the foot and ankle muscles. “Perform them slowly, taking three seconds to lower yourself down, and make sure to keep the entire ball of your foot on the ground as you move up and down,” she says.