Your posterior tibial tendon is in your lower leg, underneath your shin muscles. The tendon runs from slightly above your ankle to the inner arch of your foot. Overuse, like the repetitive movements of running or playing sports, can cause the posterior tibial tendon to become strained or ruptured. Tight calf muscles can also cause pain in your ankle from an injured tendon. Stretching exercises for your lower legs can stretch the posterior tibial tendon and help prevent discomfort.
Perform ankle-flexing exercises to stretch a weak tendon. Tie one end of a resistance band around a chair, and the other end around the ball of your foot. Flex your ankle so that your toes are pointing toward the ceiling; you should feel the band trying to pull you toes away from your body as you flex. Keep your knee still so that you're moving only your ankle to perform the stretch.
Stretch your calves to loosen up the muscles and to stretch your tendon. Stand facing a wall with your toes also pointing toward the wall. Take a step forward with one leg in order to stretch out your back leg. Push your hands against the wall, bending your front knee but keeping your back leg as straight as possible. Hold the stretch for up to 30 seconds, if you can.
Participate in heel-walking exercises. Lift up your toes and balance on your heels, pointing your toes out to the sides. This position of your foot causes your ankles to flex, which stretches the posterior tibial tendon. Work up to heel-walking for two minutes at a time to strengthen your lower legs.
Stretch your arches with toe scrunches. Curl up your toes as if you were going to pick something up off the floor with your toes. You can actually pick up marbles or other small items if the action helps you perform the stretch correctly.