Estimated read time: 3–4 minutes
The Truth About Tendon Pain
If you’ve ever been told to “just stretch it out” when your Achilles, knee, or elbow started to ache — you’re not alone.
For years, that advice was the norm. But modern research is clear: tendons don’t respond to stretching the same way muscles do.
When you feel that stiff, achy, or burning sensation in a tendon, whether it’s your Achilles after a long run or your elbow after lifting — it’s rarely because it’s too tight. It’s because the tendon’s load capacity has been exceeded.
Understanding Tendon Physiology
Tendons are the strong connective tissues that anchor muscle to bone. Unlike muscles, they have limited blood flow and a slower adaptation rate. Their structure is mostly collagen fibers, arranged like a rope designed to transfer force.
When a tendon is overloaded — from too much, too soon, or without enough recovery — the collagen fibers begin to lose their organized pattern. This isn’t the same as a “tear,” but rather a disorganization that causes pain, stiffness, and weakness.
This condition is called tendinopathy.
Here’s what the latest research shows:
- Passive stretching does not stimulate tendon healing.
- Eccentric (lengthening) and isometric (static contraction) exercises, however, do.
These specific loading strategies tell your body to remodel and strengthen the tendon — essentially, to lay down stronger collagen fibers in a more organized way.
Why Stretching Alone Can Make It Worse
Stretching a painful tendon may temporarily relieve tightness, but it doesn’t build the structure back up.
In some cases, it can actually increase irritation, especially when done aggressively or too frequently.
Think of a tendon like a frayed rope — pulling harder on it doesn’t make it stronger; rebuilding the rope does.
The Science of Load Progression
The cornerstone of tendon rehab and performance is progressive loading — applying controlled stress to help the tendon adapt.
Here’s what that progression typically looks like:
- Isometric Holds (Pain Control Phase)
- Example: Mid-range calf raise hold for 30–45 seconds
- Purpose: Reduces pain by stimulating the nervous system and improving tendon tolerance
- Eccentric Loading (Remodeling Phase)
- Example: Slow 3–5 second lowering during a heel raise or decline squat
- Purpose: Promotes collagen realignment and increased load capacity
- Heavy Slow Resistance (Strength Phase)
- Example: Weighted calf raises or squats, 3×8 reps
- Purpose: Builds true tendon stiffness and long-term resilience
- Plyometric and Return-to-Sport Phase
- Example: Hops, skips, and running drills once baseline strength returns
- Purpose: Restores energy storage and release, mimicking sport demands
Pain Does Not Equal Damage
One of the most important mindset shifts for athletes and active individuals is this:
Pain is a signal, not a stop sign.
During the loading process, some mild discomfort (2–3/10) is actually expected and safe.
Research shows that as the tendon adapts, the same load produces less pain — a sign that capacity is improving.
Key Takeaways
✅ Stretching doesn’t rebuild tendon tissue — loading does.
✅ Controlled stress = healing stimulus.
✅ Mild discomfort during rehab is normal, not harmful.
✅ Progressive strength is your best long-term protection.
