Posterior Tibialis Tendonitis in Runners and Hybrid Athletes: What You Need to Know

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If you’ve ever had nagging pain along the inside of your ankle or arch that flares up the more you run, chances are you’ve met the posterior tibialis tendon. For runners and hybrid athletes, posterior tibialis tendonitis (PTT for short) can be one of those injuries that sneaks up on you, lingers, and keeps you guessing: Is it shin splints? Is it plantar fasciitis? Why does my arch hate me so much?

The good news is that once you understand how this injury happens and why it sticks around, you can tackle it head-on. So let’s break it down.

What is the Posterior Tibialis Tendon, Anyway?

The posterior tibialis muscle sits deep in your lower leg, right behind your shin bone (tibia) and towards the inner calf. Its tendon runs down behind the inside of your ankle bone (the medial malleolus) and attaches into the navicular and other small bones of your arch.

Main job description:

• Supports the arch of your foot (like a suspension cable).

• Helps you invert the foot (roll the sole inward).

• Stabilizes your foot when you push off during running, jumping, or heavy lifting.

Without it, your arch collapses, your mechanics get sloppy, and running turns into a painful mess.

How Posterior Tibialis Tendonitis Happens

Posterior tibialis tendonitis is an overload injury. Translation: the tendon gets asked to do more than it can handle, and it gets irritated.

Here are the most common ways that happens for runners and hybrid athletes:

1. Too much, too soon.
   The main reason most injuries happen. You ramp up mileage, stack too many running days in a row, or start hammering intervals without enough base. The tendon just isn’t conditioned to handle the extra load.

2. Poor biomechanics.
   Overpronation (rolling the foot inward too much) makes the posterior tibialis work overtime to hold your arch up. Over time, that tendon says, “Yeah, I’m out.” Normal pronation, however, is okay.

3. Weakness upstream.
   Weak hips and glutes = poor control of your leg = more stress dumped into your foot and ankle. It’s like asking the tendon to clean up everyone else’s mess.

4. Hybrid athlete problems.
   Think sled pushes, lunges, wall balls, and burpees in fatigued states. Add in running volume, and your posterior tibialis becomes the unsung hero that never gets recovery credit. Which is why fueling, low intensity days, and recovery strategies are so key.

5. Footwear.
   Minimal shoes with no support or old shoes past their lifespan can push the tendon over the edge, especially if you’re already prone to arch collapse.

Why Runners and Hybrid Athletes Get It

Runners get it because of the repetitive stress of mileage. Hybrid athletes get it because they’re layering high-impact running with heavy lifting, jumping, and lateral movements. It’s a double whammy.

HYROX example: Run 1,000 meters → sled push → run 1,000 meters → burpee broad jumps. Each transition asks your foot and ankle to stabilize differently. If the posterior tibialis isn’t conditioned, it becomes a bottleneck for your performance.

What It Feels Like

Symptoms of posterior tibialis tendonitis include:

• Pain or tenderness along the inside of the ankle and arch.

• Swelling around the inside ankle bone.

• Pain when pushing off the ground, especially during running or jumping.

• Difficulty balancing on one leg (because the tendon helps stabilize your arch).

• Symptoms worse after long runs, speed work, or hybrid workouts with a lot of foot loading.

It’s easy to confuse with:

• Medial shin splints (pain higher up the shin, not down into the arch, and worse with standing and walking versus rest).

• Plantar fasciitis (pain at the heel/arch bottom, not up along the tendon).

• Calf strain (pain in the muscle belly, not ankle/arch).

The key giveaway: pain and tenderness specifically along the course of the tendon, behind the ankle bone and into the arch.

Why It Sticks Around

Posterior tibialis tendonitis is notorious for being stubborn, especially for a tendon injury. Here’s why:

• We never stop using it. You literally need the tendon every time you walk, stand, or balance. Resting it completely is nearly impossible.

• We don’t train it directly. Most programs skip foot and ankle strength. Weak tendon + heavy mileage = repeat injury cycle.

• It’s often ignored early. Athletes chalk it up to “sore arches” or “shin splints” and keep training until it blows up.

How to Fix It (Without Losing Your Mind)

Here’s the good news: posterior tibialis tendonitis responds well to the right plan. The bad news? It takes patience.

1. Relative Rest, Not Couch Rest

You don’t need to stop moving. But you do need to scale back running and training that directly aggravates the tendon. Swap in biking, rowing, or swimming for aerobic work. Keep lifting, but avoid heavy lunges, jumps, or sleds that flare up symptoms.

2. Strengthen the Posterior Tibialis

The tendon needs load to adapt—just not overload. Some go-to exercises:

• Tibialis raises against a band (foot inversion with resistance; start here, but don't stay here).

• Single-leg calf raises with focus on arch control.

• Short foot exercise (arch lifts while standing, squatting, and lunges).
  Progress these slowly, with higher reps and time under tension.

3. Train the Whole Kinetic Chain

Remember: weak hips and glutes dump stress into the foot. Add in:

• Single-leg RDLs.

• Hip thrusts.

• Lateral and curtsey lunges

• Plyometrics, bounds, and jumps to restore springyness to the tendon. Yes, springyness.

4. Smart Return-to-Running Program

Just like with Achilles tendonitis, you need a progressive return:

• Start with walk/jog intervals.

• Progress to steady runs.

• Layer in tempo runs and threshold work.

• Save speed intervals for last, once the tendon is solid.

5. Strength Training is Your Friend

Heavy lifting makes tendons more resilient. Studies show that tendons adapt positively to heavy, slow resistance training (Journal of Orthopaedic & Sports Physical Therapy, 2018). Key word here is "heavy." Think:

• Heavy calf raises.

• Trap bar deadlifts.

• Split squats.

6. Recovery Tools That Actually Work

• Sleep: Tendon repair is driven by collagen turnover, which ramps up during deep sleep.

• Nutrition: Protein + vitamin C supports tendon healing.

• Stress management: High cortisol slows collagen repair (another reason why your circle matters).

• Hydration.

Why Hybrid Athletes Should Care

Hybrid athletes need to balance both volume from running and load from lifting. Posterior tibialis tendonitis doesn’t just hurt your long runs—it makes sled pushes, lunges, and even wall balls miserable.

If you ignore it, your arch can collapse over time, leading to bigger issues like flatfoot deformity or chronic ankle instability. Translation: no more races, no more chasing PRs.

But if you rehab it properly, you’ll come back with stronger arches, better balance, and more efficient running mechanics. That means faster splits, heavier lifts, and fewer injuries down the line.

Final Thoughts

Posterior tibialis tendonitis is a classic “under the radar” injury that can derail runners and hybrid athletes if left unchecked. It happens when the tendon gets overloaded, often because of weak links higher up the chain or because we ask it to handle too much, too soon.

The fix isn’t complicated, but it does require patience: scale back, strengthen the tendon, train your hips and glutes, and then progress back to running smartly. Add in heavy strength work and recovery basics, and you’ll not only beat the injury—you’ll come back stronger than before.

So if your arch is nagging and your ankle feels tender, don’t ignore it. Listen to your body, respect the tendon, and put in the boring work. Your future self—crossing the finish line pain-free—will thank you. If this is an injury you're struggling with, then click here to schedule your free call and we'll get you out of pain.