Posterior Tibialis Stretch
Seated with one leg out straight and a belt round the forefoot, you pull the outside edge of the foot toward you so the sole turns outward. That eversion reaches the tibialis posterior, the deep muscle behind the shin whose tendon slings under the arch and holds it up.
Own the movement
Set up first, then execute. Every cue below is something you can check on your next set.
Before the first rep
- Sit up straight with one leg extended and the other knee bent with the foot planted for support.
- Loop the belt, band or towel across the ball of the extended foot and take both ends in your hands.
- Lift the heel slightly clear of the floor so the ankle can rotate freely.
- Keep the extended knee straight and the kneecap pointing at the ceiling before you pull anything.
Every rep
Breathing & tempo — Breathe slowly and evenly through the hold, easing marginally further into eversion on each exhale. Never increase the pull while breathing in — that is when you overshoot.
How much, how often
Where to start, and what to change when it stops being hard.
No weight — the strap supplies the force and your arms dose it. Pull only to firm tension. Two or three holds of 15-20 seconds per side, most days of the week if the inner shin is a problem area. Progress by adding a little more toe-point to the position rather than by pulling harder on the belt.
What goes wrong
The errors that show up most often, and the cue that fixes each one.
Anchor the thigh by keeping the kneecap up. Watch the kneecap, not the foot — if it stays pointing at the ceiling the movement is happening at the ankle where you want it.
Let the toes point slightly away from you before you add the eversion. Dorsiflexion loads the gastrocnemius and soleus and shields the deeper tibialis posterior from the stretch entirely.
Stop and get it assessed. A tibialis posterior tendon that hurts behind the inner ankle and cannot manage a single-leg heel raise is a tendon problem that stretching makes worse, not better.
Add loaded work: single-leg heel raises to failure, three sets, four times a week, plus banded eversion. Arch support is a strength quality, and no amount of stretching supplies it.
Why bother
Tibialis posterior sits deeper than the calf, runs down behind the inner ankle bone and fans out under the arch of the foot. Its job is to invert the foot and stop the arch collapsing every time you take a step, so it is loaded thousands of times a run and it is a common source of pain along the inner border of the shin and behind the inner ankle.
Because it lies under the calf you cannot reach it with a wall calf stretch. Eversion — turning the sole away from the midline — is the only direction that lengthens it, and you need a strap to produce that pull while the muscle stays relaxed. What you get is a temporary increase in accessible eversion and some relief along the inner shin, not a cure for a tendon that has been overloaded for months.
Where it fits
After running or at the end of a lower-body session, grouped with your calf stretches. Two or three holds of 15-20 seconds per side. If you have inner shin pain, pair it with heavy heel raises done with a ball squeezed between the ankles — loading this tendon is what changes it; the stretch only makes the next few hours more comfortable.
If this one isn't it
No kit, too hard, or too easy — here's where to go instead.
Same job, different kit
Start here instead
When this gets easy
Asked and answered
How do I know I am actually stretching the right muscle?
You should feel it deep along the inner border of the shin, roughly a hand's width above the inner ankle bone, and sometimes behind the ankle bone itself. If the sensation is in the meat of the calf at the back, your ankle is flexed upward instead of pointed and you are stretching the gastrocnemius. Point the toes and try again.
Is this the same as stretching for shin splints?
It addresses the medial kind — the pain along the inner edge of the tibia that comes on during running. Tibialis posterior and soleus both attach along that border. It does nothing for pain on the outside of the shin, which is peroneal territory. And in both cases the durable fix is less running volume for a fortnight plus stronger calves, not more stretching.
Can I do this standing?
Not usefully. Standing on the outer edge of the foot loads the ankle in the position that sprains it, and you cannot relax the muscle you are trying to lengthen while it is holding you up. Sitting with a strap is the version worth doing — it is the only one where the muscle is off duty.
Do I need orthotics for a flat arch?
Not as a first move. An arch support props the foot up from underneath, which relieves symptoms quickly but leaves tibialis posterior no reason to get stronger. Spend three months on loaded work first — single-leg heel raises to failure four times a week, plus banded eversion — then reassess. Orthotics earn their place when the tendon is already failing, or as a temporary crutch while the strength work catches up. As a permanent first answer to a flat foot in someone who is not in pain, they are oversold.