Tendinopathy: Eccentric Training and Injection Options Explained

If you’ve been dealing with persistent tendon pain-whether it’s your knee, heel, or shoulder-you’re not alone. Tendinopathy affects about 30% of all sports medicine patients, and it doesn’t just hit athletes. Office workers, parents, and retirees all get it. The good news? You don’t need surgery or endless injections to fix it. The best evidence points to two powerful tools: eccentric training and smart injection choices.

What Exactly Is Tendinopathy?

Tendinopathy isn’t just inflammation. That’s the old idea. Today, we know it’s a degenerative breakdown of tendon tissue-think frayed ropes, not swollen ones. Pain comes from nerve growth and chemical changes in the tendon, not swelling. You’ll feel it when you jump, run, or even stand up after sitting. It lingers for months, sometimes years, if you don’t treat it right.

The two most common sites? The Achilles (back of the ankle) and patellar (front of the knee). These tendons take the most load. Runners, basketball players, and dancers get hit hard. But so do people who stand all day or suddenly start walking more.

Eccentric Training: The Gold Standard

Eccentric training means slowly lowering your weight under control. Think of lowering yourself into a squat, or lowering your heel from a raised position. It’s not about lifting fast-it’s about controlling the descent.

In 1998, Dr. Hakan Alfredson showed that doing 180 heel drops a day for 12 weeks helped 80% of people with Achilles tendinopathy get back to running. Since then, dozens of studies have confirmed it works for other tendons too.

For Achilles tendinopathy: Stand on a step, rise up on both feet, then lower down slowly on just the painful foot. Do 3 sets of 15 reps, twice a day. Keep your knee straight to target the calf muscle (gastrocnemius), then bend your knee slightly to hit the deeper soleus muscle. Rest 60-90 seconds between sets. You’ll feel pain-around 4-6 out of 10. That’s normal. If it hits 8 or higher, or lasts more than 24 hours, you’re pushing too hard.

For patellar tendinopathy: Use a 25-degree decline board. Do single-leg squats, lowering slowly over 3-5 seconds. Three sets of 15 reps, daily. The decline board increases the load on the tendon just enough to trigger healing without tearing it.

Studies show this kind of training increases tendon stiffness by 15-20% and realigns collagen fibers. Ultrasound scans after 8-12 weeks show the tendon thickens and looks healthier. VISA scores-a measure of pain and function-improve by 40-65% in most people.

Heavy Slow Resistance: A Strong Alternative

You don’t have to do Alfredson’s protocol to get results. Heavy slow resistance (HSR) training works just as well-and many people stick with it longer because it hurts less at first.

HSR means lifting a weight that’s about 70% of your max, slowly. For example: leg press or seated calf raise. Lift in 3 seconds, lower in 3 seconds. Three sets of 15 reps, three times a week.

A 2015 study comparing HSR to eccentric training for Achilles tendinopathy found both groups improved by 60-65% after 12 weeks. But HSR had an 87% adherence rate. Eccentric training? Only 72%. Why? Because HSR doesn’t start with extreme pain. It builds up gradually.

If you’re new to exercise or hate the idea of doing 180 heel drops a day, HSR is your friend. It’s easier to fit into a routine. And it works.

Isometric Exercises: Quick Pain Relief

Eccentric training takes weeks to fix the tendon. But what if you need to play a game tomorrow? Or walk your dog without wincing?

Isometric exercises-holding a muscle still under tension-give fast relief. For the knee, sit with your leg straight, push your knee down into a rolled towel for 45 seconds. Repeat five times. For the ankle, stand with both feet flat, press your heels down hard into the floor for 45 seconds. Do this before activity.

Rio et al.’s 2015 study showed isometrics cut pain by 50% within 45 minutes. Eccentric training? Only 20%. That’s why many physical therapists now do isometrics first, then eccentric later in the day.

Injection Options: What Actually Works?

Injections are tempting. Quick fix. But they’re not magic.

Corticosteroid injections: These reduce pain fast-30-50% improvement in 2-4 weeks. Great for getting through a big event. But here’s the catch: 65% of people need another treatment within six months. The tendon keeps breaking down. Studies show people who get steroid shots are more likely to rupture their tendon later. Don’t use them unless you’re desperate.

Platelet-rich plasma (PRP): This sounds fancy. You get your own blood spun down, then injected into the tendon. Sounds natural, right? But a 2020 review found PRP only beats placebo by 15-20% at six months. That’s not enough to justify the cost (often $500-$1,000 per shot). Most insurance won’t cover it.

Other injections: Dry needling, sclerosing agents, or bone marrow aspirate? No strong evidence. Some help a few people. But no consistent results. Don’t waste your money unless you’ve tried exercise first.

Bottom line: Injections are a band-aid. Eccentric or HSR training is the cure.

Why Some People Don’t Get Better

About 30% of people don’t respond to eccentric training. Why?

One big reason: they don’t do it long enough. You need 12 weeks minimum. Most people quit after 4-6 weeks because they don’t see results. But ultrasound changes take time. Pain reduction starts around week 6. Structural healing shows up at week 10-12.

Another reason: bad form. Doing decline squats with your knee caving in? Or letting your heel wobble during heel drops? That shifts load away from the tendon. A 2023 study found self-managed patients made mistakes 40% more often than those working with a therapist.

Third reason: they ignore load management. You can’t do 180 heel drops and then go for a 10K run the same day. You need to reduce high-impact activity while you rebuild. Gradual return is key.

How to Stay on Track

Success comes down to consistency.

- Use an app like Tendon Rehab (version 3.2, 2023). It tracks reps, gives video demos, and reminds you. Users with apps had 85% adherence. Paper logs? Only 65%.

- Work with a physical therapist for the first two sessions. They’ll check your form, adjust your pain tolerance, and help you scale up. People who did this had a 92% success rate. Those who went solo? 68%.

- Track your pain. Use a 1-10 scale. Acceptable pain during exercise? 2-5. Pain that lasts more than 24 hours? Stop and back off.

- Don’t compare yourself to others. Your tendon heals at your pace. Some people feel better in 8 weeks. Others need 16. That’s normal.

What’s Next for Tendinopathy Treatment?

The field is moving toward precision rehab. Instead of one-size-fits-all protocols, doctors are starting to test tendon stiffness, pain response, and even biomarkers to tailor treatment.

A 2022 study showed that adjusting load based on individual tendon tolerance improved outcomes by 25%. That’s huge.

Researchers are also testing new drugs that target tendon cells directly. Phase II trials for a peptide called TAP-421 start in early 2024. But that’s years away from being available.

For now, the best tools are simple: load the tendon correctly, be patient, and avoid shortcuts.

Real People, Real Results

On Reddit, one runner wrote: “I did the heel drops for 14 weeks. Week 1-3 were hell. Week 6, I could walk without limping. Week 12, I ran 5K. Two years later, no pain. Worth every second.”

Another said: “I got a steroid shot. Felt great for a month. Then back to square one. I wish I’d just done the squats.”

The data backs them up. In a 2021 survey of 452 runners with Achilles tendinopathy, 82% who completed eccentric training returned to their previous activity level. Only 58% of those who got injections did.

Final Takeaway

Tendinopathy isn’t a death sentence. It’s a slow healing process that rewards patience and consistency. Eccentric training and heavy slow resistance are proven, effective, and cheap. Injections? Use them sparingly, if at all.

Start with isometrics for quick pain relief. Then build into eccentric or HSR training. Do it daily. Track your pain. Get form checked. Stick with it for 12 weeks. Most people who do this get back to doing what they love-without surgery, without shots, without giving up.

If you’ve been told to rest and wait, you’ve been given the wrong advice. Tendons heal with load-not rest. Time to load them right.