If you're dealing with Achilles tendon pain, you've probably been told to "load it up" - do your calf raises, build strength, and the pain will follow. It's solid advice, but new research is showing the relationship between strength and pain is more complicated than we once thought. Here's what we now know, and what it means for your recovery.
Achilles Pain? Why "No Pain, No Gain" Isn't the Whole Story
Getting stronger doesn't always mean feeling better
For years, the assumption in tendon rehab has been simple: if your calf and Achilles get stronger, your pain should go down too. Recent research has actually put this to the test and the results are surprising.
A 2023 review found no clear link between changes in tendon pain and changes in Calf/Achilles strength or structure during rehab.
In other words, pain and strength can improve on completely separate timelines. One 12-week study comparing different loading programmes found that a heavy, high-load approach produced the biggest gains in tendon strength and stiffness — but patients getting that treatment didn't report any less pain than patients doing a much gentler, lower-load programme. Everyone's pain improved by roughly the same amount, regardless of how much stronger their tendon actually got.
Another study looked at how much force went through the Achilles during common rehab exercises, from gentle heel raises through to running and hopping, and compared that to how much pain people reported. For about half of the people studied, there was little to no connection between how hard they were loading the tendon and how much pain they felt.
What this means for you: if your pain isn't dropping as fast as you'd like, it doesn't necessarily mean your tendon isn't getting stronger or that your rehab isn't working. Pain and tissue health are two different things we need to track separately.
Why does pain behave this way?
Tendon pain isn't purely a "damage" signal. Your nervous system's sensitivity, your beliefs about the injury, fear of movement, and even general health factors can all turn the pain "volume" up or down independently of what's actually happening in the tendon tissue. This is why two people with an identical-looking Achilles on a scan can have completely different pain experiences.
This is also why we see different types of presentations in the clinic:
- Activity-driven: Often younger, active people who've simply overloaded a healthy tendon by doing too much, too soon. The fix here is usually a short deload followed by a gradual rebuild in capacity.
- Fear and sensitivity-driven: People whose nervous system has become overly protective, often after a scare about "damaging" the tendon further. Here, the priority is rebuilding confidence and gradually proving to the body that load is safe - not just pushing harder on exercises.
- Tendon health-driven: Sometimes there are underlying metabolic or hormonal factors (more common with age, but sometimes seen in younger athletes too) that mean the tendon itself needs extra support - through diet, general health, and medical input alongside physio, rather than simply loading it harder.
This is exactly why a one-size-fits-all exercise sheet often falls short, and why a proper assessment matters.
So what actually works? A staged loading approach
The most consistent theme across the research is that progressive tendon loading done in the right order, at the right intensity is what drives real change. Here's the general shape of an evidence-based programme:
1. Start with isometrics (holding, not moving). Early on, holding a contraction (like a sustained calf raise hold) at a shorter, less-stretched tendon position is usually the safest and most comfortable place to start. Aim for holds of around 20–30 seconds, repeated 6–12 times, at a solid but tolerable intensity.
2. Gradually lengthen the range. As things settle, we progress the exercise so the tendon is working from a more stretched position. This is more challenging but drives better adaptation, provided it's introduced gradually.
3. Add isotonic strengthening (movement through range). Think progressing from a double-leg calf raise, to single-leg, to loaded single-leg raises, building the muscle-tendon unit's day-to-day capacity.
4. Introduce plyometrics (bouncing/springy loading) earlier than you'd think. Contrary to the old idea of "save the bouncy stuff for the very end," gentle plyometric preparation can often begin alongside isometric and strength work, rather than being left until the last stage of rehab.
5. Keep a "holding" exercise in your programme the whole way through. Even once you're doing more dynamic strength work or jumping-based exercises, it's worth keeping a simple isometric hold in the mix, especially at that more stretched tendon position, right through to the end of your rehab.
The takeaway
Achilles tendon rehab isn't just about grinding through calf raises and waiting for the pain to disappear. Progress in strength and progress in pain can happen at different speeds, and that's normal. What matters most is a properly staged, individualised loading programme, built around an assessment of what's actually driving your particular presentation.
If you're dealing with ongoing Achilles pain and want a plan that's built around your specific tendon, your activity levels, and what's realistically driving your symptoms, get in touch with the team at Bureta, we'll assess you properly rather than handing you a generic sheet of exercises!