Beyond Load and Function: What Tendon Pain Is Really Telling Us

Defining Function in Tendon Rehab

Professor Jill Cook writes,

"There are clear [relationships] between structure, pain and function, and a number of reviews have focused on this complex relationship in tendons."

That quote sets the stage. Yet in practice, we often reduce the assessment of “function” to a single-joint test like a calf raise — judged as either competent or not. Perhaps we measure capacity with reps, or use hop tests to assess storage and release. But are we truly evaluating function in the way it’s defined?

Function in this context refers to the ability of the muscle to repeatedly generate appropriate force that enables the tendon to store and release energy for athletic movement.

That definition is far richer than most test protocols reflect. It demands control, repetition, energy storage, and appropriate force generation — integrated within athletic movement, not just isolated performance.

Tendon Pain: More Than Just a Functional Issue

Cook also clarifies:

"Tendon pain is partly related to function, with tendinopathy decreasing muscle strength and motor control, which in turn reduces function."

So if tendon pain is only partly related to function, the clinical question becomes: What else is it related to?

To answer that, we must revisit the broader risk factors for Achilles-area pain — not just loading patterns or test outputs, but contributions from:

• Underlying systemic health

• Movement dysfunction and asymmetries

• Previous injuries or persistent compensations

• Environmental and training loads

Reassessing the Role of Load in Tendon Rehab

Rehab models often emphasize progression:

• Isometric →

• Eccentric →

• Slow Heavy Load →

• Energy Storage →

• Sport Specificity

But even within these models, a deeper layer of movement assessment is needed. Tom Goom, in his guide on Tendinopathy - functional rehab, highlights the need to:

• Improve load capacity across the kinetic chain

• Identify movement dysfunctions contributing to tendon load

This aligns directly with Cook's framing. Tendon pain often sits at the intersection of structure, pain sensitivity, motor control, and functional misadaptation.

Integrating Movement-Based Reasoning

We need to go beyond kinesiological capacity testing and ask:

• Can the athlete coordinate force and absorb it across multiple joints?

• Do they possess the motor control required to handle elastic recoil?

• Is their system tolerant of rapid transitions between contraction types?

When “function” is redefined through this broader lens, our testing and our treatment must adapt accordingly. SFMA, DNS, and similar systems become essential—not for their novelty, but for their capacity to map dysfunction upstream of the tendon.

Conclusion: Let’s Widen the Lens

Tendon pain is not just a loading issue. Nor is it just a strength issue. It’s a systems issue — one that demands we evaluate more than the painful part.

As clinicians, we must respect the tendon, respect the complexity of “function,” and respect the role of movement in both provoking and resolving pain.

Fix the pattern. Understand the context. Then load it intelligently.

References:

1. Cook, J. L., Rio, E., Purdam, C. R., & Docking, S. I. (2016). Revisiting the continuum model of tendon pathology. British Journal of Sports Medicine, 50(19), 1187–1191.

2. Goom, T. (n.d.). Tendinopathy – functional rehab. Running-Physio.com.

3. van der Vlist, A. C., et al. (2019). Clinical risk factors for Achilles tendinopathy: a systematic review. British Journal of Sports Medicine, 53(21), 1352–1361.

4. Wainner, R. S., et al. (2007). Regional interdependence: A musculoskeletal examination model whose time has come. Journal of Orthopaedic & Sports Physical Therapy, 37(11), 658–670.