The tibialis posterior muscle is the leg muscle that points the foot down and in, and it plays a key role in keeping the arch of your foot stable during walking and running. Problems with this muscle can present themselves as pain on the inside of the ankle, a collapsing arch or difficulty standing on your toes. Symptoms can mimic other conditions, though, and a proper exercise program should be developed by a doctor and physical therapist. A program may include stretching, strengthening and stability exercises.
Stretching a tight muscle can relieve symptoms of stiffness and allow the muscle to function more effectively. The tibialis posterior can be stretched by pulling the ankle and toes outward and upward. Because a fully stretched position can be awkward to achieve on your own, stretching the foot with a belt or enlisting the help of a second person can sometimes provide better results. Sometimes, stretching other muscles that have similar functions can help. Stretches targeting the calf muscles and big toe may help parts of the tibialis posterior.
Range of Motion
If the tibialis posterior is weak or painful, active range-of-motion exercises may be recommended even before you start any resistive strengthening exercises. Moving the muscle through its range is vital to prevent stiffness in the ankle and foot. Performing a full range of motion involves starting with the foot and toes pointed downward and inward, and ending with the foot and toes pointed upward and outward. If a certain part of the range of motion is painful, physical therapists typically recommend avoiding that movement and focusing on movement you can make without pain.
Elastic bands or tubing are excellent ways to target the tibialis posterior. A cuff weight placed around the midfoot can also provide resistance. Pointing the toes and foot down and in, against the resistance of a band, will work to contract the tibialis posterior, building strength in that way. Slowly allowing the band to pull your foot and toes back up and out builds strength in a different way -- the lengthening of the muscle. Research indicates tendinitis can be effectively treated by using lengthening exercises. Band thickness, the number of repetitions and the amount of weight can be advanced over time to build strength.
Weight-bearing exercises are valuable because they parallel the movements of real life and because we spend so much time on our feet. Most exercise programs working on this muscle also include a weight-bearing component. Walking on your toes, performing heel raises or actively creating an arch with your foot while standing may all target the tibialis posterior.
Certain injuries to the tibialis posterior or seeming to relate to this muscle can actually worsen with exercise. Also, what seems to be a problem in the tibialis posterior muscle may actually be a result of a tight or weak muscle elsewhere in the body or a different injury entirely. If any exercise increases pain or elicits new symptoms, discontinue it and consult a doctor or physical therapist. A trained health-care professional will be able to assess your symptoms and determine which interventions might help.