Tibialis Posterior

Foot function anatomy and strengthening for athletes

The tibialis posterior, also commonly called the posterior tibialis, is a deep calf muscle whose tendon passes behind the inner ankle and attaches to several bones of the foot. It helps support the medial longitudinal arch, turns the foot inward, and assists with plantar flexion, the movement used to point the foot downward.[1,2]

For athletes, understanding this muscle helps connect foot anatomy with practical training. The aim is to develop a foot that can accept load and contribute to push-off, while recognizing when shin or inner-ankle pain needs assessment.

Anatomy of the Tibialis Posterior

Origin

Posterior tibial and fibular surfaces and the interosseous membrane.[1]

Insertion

The navicular is a major attachment. Tendon slips also attach to the cuneiforms and other midfoot structures, commonly including the bases of the second to fourth metatarsals. The precise attachment pattern varies between individuals.[1,8]

Primary Actions

Inversion, turning the sole inward; adduction, moving the forefoot inward; assistance with plantar flexion; and dynamic support of the medial longitudinal arch.[1]

Its broad insertion links tibialis posterior to several parts of the foot, explaining why its role extends beyond lifting a single point of the arch.[1,8]

Exercise 1 | Resisted inversion with slight plantar flexion

Purpose: Apply resistance to inward foot movement, with the foot pointed slightly downward. This targets a major action of tibialis posterior, although other muscles also contribute.[1,9]

1. Sit with your lower leg supported and your foot free to move.
2. Loop a resistance band around the forefoot and anchor it toward the outside of the exercising foot so that it pulls the foot outward.
3. Point the foot slightly downward, then move the forefoot inward against the band.
4. Keep the knee and hip still. Return slowly, without letting the band pull the foot outward suddenly.

Technique cues: Keep the toes relaxed, use a comfortable range, and avoid turning the whole leg. Begin with resistance that allows smooth movement. Progress the band resistance when you can maintain the same control throughout the set.

Related option: For a seated inward foot slide, keep the same band pulling the forefoot outward. Place the forefoot on a small towel on a smooth floor, keep the heel planted and knee still, and slide the forefoot inward against the band. This is an alternative loading option, not a separately proven superior exercise.[9,10]

Exercise 2 | Supported double-leg heel raise

Purpose: Train the calf and foot-support muscles together. Heel raises load tibialis posterior, but they do not isolate it.[9]

1. Stand on level ground with both feet in a comfortable position and hold a stable support lightly.
2. Rise onto the balls of the feet, maintaining pressure through the base of the big toe and the rest of the forefoot.
3. Lower smoothly and repeat without bouncing.

Technique cues: Avoid gripping the toes or shifting all your weight onto the outside edges of the feet. A small natural inward movement of the heel can occur; do not force the ankle into a rolled-out position. Start on the floor before considering the extra range available from a step.

Does toe position matter? In 14 healthy men, heel raises with the feet turned inward 30 degrees increased tibialis posterior activity compared with the other tested positions. This was an activation study, not proof of better treatment results. A comfortable neutral position remains a sensible starting choice; a forced toe-in stance is unnecessary.[11]

Exercise 3 | Assisted then loaded single-leg heel raise

Purpose: Increase the demand once double-leg heel raises are well controlled. Single-leg heel raises produced substantial tibialis posterior recruitment in laboratory studies.[9,10]

1. Stand on one leg beside a stable support, using enough hand assistance to maintain balance and movement quality.
2. Raise the heel through a comfortable range, then lower under control.
3. Keep the forefoot supported and maintain a consistent heel-rise height from one repetition to the next.

Progression: Reduce hand assistance, then add external resistance, such as a dumbbell or a loaded backpack, as appropriate. If a full single-leg rise is too difficult, rise with both feet and shift somewhat more weight to one side for the lowering phase. This is a loading modification, not evidence that eccentric-only exercise is always better.

A heel raise challenges several muscles, balance, and tolerance to load. Repetition count alone should not be used to diagnose tibialis posterior weakness or decide whether an athlete is ready to return to sport.

Exercise 4 | Short-foot control with standing integration

Purpose: Add whole-foot control to the strengthening program. This is a complementary exercise involving the intrinsic foot muscles; it is not selective tibialis posterior training.

1. Sit with the heel, base of the big toe, and base of the little toe resting on the floor.
2. Gently draw the ball of the foot toward the heel to create a small arch, without curling the toes or rolling onto the outer edge.
3. Relax, repeat, and then practise the same gentle control in standing or during a slow supported single-leg task.

A 2024 trial in people with flexible flatfoot found benefits in selected foot-posture and balance measures from a program combining tibialis posterior strengthening and short-foot exercises. Because the exercises were combined, the results do not identify the effect of either one alone, and they do not establish injury prevention.[12]

< Take-Home Message >

Tibialis posterior supports the arch and foot control. Train it with resisted inward foot movement and progressive heel raises, supported by whole-foot exercises. Build strength across the lower leg, and have persistent shin or inner-ankle pain assessed.