What are the most common symptoms of tendon injuries?

1. Pain

- Usually localized to the tendon area

- Worsens with activity or loading (e.g., jumping, lifting)

- May present as a dull ache or sharp pain depending on severity

- Sometimes worse in the morning or after periods of rest

2. Stiffness

- Common in the morning or after inactivity

- Improves with gentle movement or warm-up

3. Decreased Strength or Performance

- Difficulty generating force (e.g., weak push-off, slower sprint)

- Fatigue or muscle inhibition around the tendon area

Where do tendon injuries commonly occur?

Most tendon injuries occur at the interface between tendon and muscle — typically the myotendinous junction (MTJ) or the enthesis (where tendon meets bone).

But why these areas?

● Uneven Load Distribution

Tendons aren’t uniform. Their structure varies along their length — proximal portions are more compliant, while distal parts are stiffer. This means certain areas experience more strain during activity.

● High Mechanical Demand Zones

The MTJ is where muscle contraction turns into tendon tension. It’s also where energy storage and shock absorption happen — often under high-speed or high-load conditions (e.g., sprinting, jumping).

● Stress Concentration at Transitions

These junction zones are structural transition points, which can lead to stress concentration — especially when combined with fatigue, overload, or poor movement patterns.

What are the key components of tendon rehabilitation?

Tendon injuries can occur when an underprepared tissue is exposed to unaccustomed load. So the solution isn't rest — it's progressive, strategic loading that considers:

1. Timing – Start loading early, within tolerance.

2. Type – Use isometrics early, then progress to isotonic and eccentric/concentric strength.

3. Target – Address the region of injury, not just the whole tendon.

4. Progression – Move from simple to complex, isolated to integrated.

How do we start loading tendons?

Tendons respond positively to mechanical loading — it stimulates collagen synthesis, increases tendon stiffness, and improves tensile strength.

● Early Loading Promotes Recovery

In muscle-tendon injuries, introducing load as early as day 2 has been shown to improve return-to-play timelines. It encourages healing without compromising tissue integrity — as long as the load is appropriate.

● Isometrics Offer a Low-Threat Starting Point

Low-jerk isometrics (isometric contractions that avoid rapid force spikes) can help reduce pain and protect the healing tendon in early stages.

● Heavy Slow Resistance Builds Long-Term Capacity

Over time, transitioning to heavy slow resistance (HSR) training — e.g., 3–4 sets of 6–8 reps — improves tendon structure and function. And when combined with isometrics, this approach has an additive effect on tendon strength.

What is the end goal?

As physios, the goal isn’t just to manage pain — it’s to restore function, build resilience, and guide the tendon back to handling load confidently. And that starts with listening to the symptoms and understanding what they’re telling us.

Tendons don’t need rest — they need the right kind of loading, at the right time.

Source:

From the lecture ‘Isometric Training for Tendon Rehabilitation' by Dr. Keith Baar