Tibialis Posterior Exercises: Support Your Arch and Fix Flat Feet

Hidden deep in your lower leg lies one of the most important muscles for foot health—the tibialis posterior. This often-overlooked muscle is the primary dynamic support for your arch. When it weakens, flat feet, overpronation, and posterior tibial tendon dysfunction follow. Strengthening it can transform your foot function.

Understanding the Tibialis Posterior

The tibialis posterior is the deepest muscle of the posterior lower leg. It runs from the tibia and fibula, passes behind the medial malleolus (inner ankle bone), and fans out to insert on multiple bones of the midfoot.

Location: Deep to the gastrocnemius and soleus (calf muscles), running down the back of the lower leg.

Primary functions:

• Plantarflexion (pointing foot down)
• Foot inversion (turning sole inward)
• Primary dynamic stabilizer of the medial arch
• Controls pronation during gait
• Essential for push-off phase of walking/running

Why it's so important:

• Main muscle supporting your arch
• Prevents excessive pronation (flat foot)
• Critical for single-leg stability
• Essential for running and jumping
• Weakness leads to significant dysfunction

Conditions linked to tibialis posterior dysfunction:

• Adult-acquired flat foot (fallen arches)
• Posterior tibial tendon dysfunction (PTTD)
• Overpronation
• Medial ankle pain
• Shin splints (medial type)
• Plantar fasciitis (related)

Signs of Tibialis Posterior Weakness

Visual Signs

• Flat arches when standing
• "Too many toes" sign (when viewed from behind, multiple toes visible on outer edge)
• Heel tilts inward (valgus)
• Arch collapses during single-leg stance

Functional Signs

• Difficulty rising onto single-leg tiptoe
• Pain along inner ankle or arch
• Fatigue with prolonged standing
• Difficulty with balance on one leg
• Foot rolls inward during running

Single-Heel Rise Test

1. Stand on one leg
2. Rise onto tiptoes
3. Watch the heel—it should move inward (inverting)
4. If heel stays straight or tilts outward, tibialis posterior weakness likely
5. Test both sides, compare

Beginner Exercises

Seated Foot Inversion with Band

The foundational exercise:

1. Sit with legs extended
2. Loop band around forefoot
3. Anchor band to something on outer side
4. Turn sole of foot inward against resistance
5. Control return
6. 15-20 repetitions each foot

Towel Scrunch (Short Foot)

1. Sit with foot flat on towel
2. Scrunch towel toward you using your toes
3. Focus on raising the arch, not just curling toes
4. Release and repeat
5. 15-20 repetitions each foot

Short Foot (Arch Lift)

1. Stand or sit with foot flat on ground
2. Without curling toes, "shorten" your foot by raising the arch
3. Toes stay flat, heel stays down, arch lifts
4. Hold 5 seconds
5. 15-20 repetitions each foot

Key: This is a subtle movement—the foot shortens maybe 1 cm. Focus on the arch, not the toes.

Seated Calf Raise with Inversion

1. Sit on chair, feet flat on floor
2. Raise heels (calf raise)
3. At the top, turn heels outward (inverting foot)
4. Lower with control
5. 15-20 repetitions

Standing Arch Lift

1. Stand barefoot
2. Lift arch without curling toes (short foot exercise)
3. Hold 5 seconds
4. 15-20 repetitions each foot

Intermediate Exercises

Single-Leg Balance with Arch Control

1. Stand on one leg
2. Maintain arch height (don't let it collapse)
3. Hold 30-60 seconds
4. Progress to eyes closed

Heel Raises with Inversion Focus

1. Stand on edge of step
2. Rise onto tiptoes
3. At top, focus on keeping weight on big toe side
4. This engages tibialis posterior
5. 15 repetitions

Single-Leg Heel Raise

1. Stand on one leg
2. Rise onto tiptoes
3. Watch that heel inverts (turns inward) at top
4. Lower with control
5. 12-15 repetitions each leg

Band Inversion (Standing)

1. Stand with band around forefeet
2. Step to widen stance, creating tension
3. Practice turning soles inward against band
4. 15 repetitions

Resisted Ankle Inversion in Plantarflexion

1. Sit with ankle in pointed position
2. Band resistance on inner foot
3. Turn sole inward (inversion)
4. This specifically targets tibialis posterior
5. 15 repetitions each foot

Step-Down with Arch Control

1. Stand on step
2. Slowly lower opposite foot toward floor
3. Don't let standing arch collapse
4. Control the movement
5. 12 repetitions each leg

Advanced Exercises

Single-Leg Heel Raise (Eccentric)

1. Rise onto tiptoes using both legs
2. Shift weight to one leg
3. Lower slowly (4-5 seconds) on single leg
4. Repeat
5. 10-12 repetitions each leg

Single-Leg Jump Landing

1. Small hop onto one leg
2. Land with controlled arch (no collapse)
3. Stick the landing
4. 10 landings each leg

Walking Lunges with Arch Focus

1. Perform walking lunges
2. Focus on maintaining arch of front foot
3. Don't let foot collapse inward
4. 10 lunges each leg

Lateral Hop with Controlled Landing

1. Hop sideways onto one leg
2. Land with stable arch and ankle
3. Stick landing before next hop
4. 10 hops each direction

Stair Running with Arch Focus

1. Run up stairs
2. Focus on pushing off through big toe
3. Maintain arch engagement
4. Sport-specific tibialis posterior work

Bulgarian Split Squat with Arch Control

1. Rear foot elevated
2. Front foot performing the work
3. Maintain arch of front foot throughout
4. 10 repetitions each leg

Stretching and Mobility

While strengthening is primary, address any tightness:

Calf Stretch (Soleus Focus)

1. Wall stretch with knee bent
2. Feel stretch lower in calf
3. Hold 30 seconds each side

Tibialis Posterior Stretch

1. Sit with one leg crossed over other
2. Hold foot and gently evert (turn sole outward)
3. Feel stretch along inner lower leg
4. Hold 30 seconds each side

Self-Massage

1. Use lacrosse ball or thumbs
2. Work along inner shin, behind tibia
3. Also massage inner arch of foot
4. 1-2 minutes each leg

Sample Programs

Flat Foot Rehabilitation (Weeks 1-4)

Daily:

1. Short foot exercise: 3 × 15 each foot
2. Seated band inversion: 3 × 15 each foot
3. Towel scrunches: 2 × 15 each foot
4. Single-leg balance: 3 × 30 seconds each

Building Strength (Weeks 5-8)

Daily or every other day:

1. Short foot: 3 × 15 each foot
2. Single-leg heel raise: 3 × 12 each leg
3. Band inversion: 3 × 15 each foot
4. Step-down with arch control: 2 × 12 each
5. Single-leg balance: 2 × 45 seconds each

Advanced Function (Weeks 9+)

3-4x per week:

1. Single-leg eccentric heel raise: 3 × 10 each
2. Single-leg jump landing: 3 × 10 each
3. Lateral hop with landing control: 2 × 10 each
4. Bulgarian split squat: 2 × 10 each
5. Walking lunges with arch focus: 2 × 10 each

Runner's Maintenance

2-3x per week:

1. Short foot: 2 × 15 each foot
2. Single-leg heel raise: 2 × 15 each
3. Single-leg balance: 2 × 45 seconds each
4. Stair running focus: 1-2 minutes

Working with Other Foot Muscles

Tibialis posterior doesn't work alone:

Intrinsic foot muscles: Strengthen with towel scrunches, short foot exercises.

Peroneal muscles: Balance inversion (tibialis posterior) with eversion (peroneals).

Calf complex: Work together for plantarflexion.

Complete foot/ankle session:

1. Short foot exercise: 2 × 15 each
2. Tibialis posterior (band inversion): 2 × 15 each
3. Peroneal work (band eversion): 2 × 15 each
4. Calf raises: 2 × 15
5. Single-leg balance: 2 × 30 seconds each

Common Mistakes

Curling Toes Instead of Lifting Arch

In short foot exercise, the arch should lift while toes stay relaxed. Toe curling is cheating.

Allowing Arch Collapse During Exercises

If your arch collapses during single-leg work, the exercise is too hard. Regress and build strength first.

Neglecting Single-Leg Work

Bilateral exercises don't challenge the tibialis posterior like single-leg work does. Progress to single-leg.

Ignoring Pain

Medial ankle or arch pain during exercise means something's wrong. Modify or rest.

Not Being Consistent

Arch strength takes time to build. Daily short foot practice and regular strengthening yield results over weeks.

When to Seek Help

See a professional if:

• Pain along inner ankle that worsens
• Visible deformity of foot/arch
• Difficulty walking due to pain
• Rapid progression of flat foot
• Swelling along inner ankle
• No improvement after 6-8 weeks of exercise
• Pain at rest or at night

Note: Posterior tibial tendon dysfunction (PTTD) is progressive. Early intervention is important.

The Bottom Line

Your tibialis posterior is the key to arch support—and it's probably weaker than it should be. Strengthening it can prevent overpronation, improve running mechanics, and address flat foot problems.

The keys:

1. Master the short foot exercise - This is the foundation
2. Progress to single-leg work - Real function requires single-leg strength
3. Focus on inversion - This is the tibialis posterior's primary action
4. Watch your arch during all leg exercises - Don't let it collapse
5. Be patient - Arch strength takes weeks to months to build
6. Address early - PTTD is progressive; don't wait
7. Integrate with foot/ankle training - Multiple muscles work together

If you have flat feet, overpronation, or medial ankle pain, tibialis posterior strengthening isn't optional—it's essential. Start with short foot exercises and band inversion today.