"How do I tell if my shoulder pain from surfing is a rotator cuff tendinopathy...or something else?"

Rotator cuff tendinopathy usually causes a dull, aching pain on the front/side of the shoulder that worsens with repetitive overhead or paddling motions and causes weakness when lifting or rotating the arm. Immediate red flags (severe deformity, numbness, fever, constant/unchanging pain) suggest something else and need urgent care. A quick shoulder pain screen + a few strength and range of motion tests can help separate tendinopathy from instability, impingement, or a full rotator cuff tear.

Quick signs of rotator cuff tendinopathy

• Dull, activity-related pain with paddling or pop-ups

• Pain with reaching behind the back (internal rotation) or to the side (abduction)

• Night pain, difficulty sleeping on that side

Immediate actions

• Modify activity (reduce paddling volume, shorten sessions or reduce frequency of sessions)

• Depending on severity, consider a short course of relative rest, anti-inflammatory supporting and anti-oxidant rich foods (Vitamin C can be effective in reducing cuff related pain) and gentle shoulder and ribcage mobility exercise

Simple self-tests

• Painful arc test: shoulder pain raising arm to the side between 60–120° (90 deg is perpendicular to the ground)

• External rotation resisted test: pain/weakness with resisted external rotation of the arm (rotating outward away from the body)

• Drop arm test: unable to keep arm up against gravity (if positive — consider more urgent assessment)

• Apley ER/IR tests: reach one arm behind the head (down the back) and the other behind the back, attempting to bring fingers as close together as possible. (If you discover a limitation in one movement, it can guide you toward selecting better exercise interventions)

Typical Rehab Overview (phases)

1. Pain control & mobility — ribcage/thoracic spine, scapular mobility, maximize shoulder ROM.

2. Restore load tolerance — progressive rotator cuff strengthening (isometric loading → concentric-eccentric loading → higher velocity loading (plyometrics)).

3. Sport-specific durability — paddling endurance, pop-up power development, shoulder strength and endurance in overhead position.

General Return-to-surf Criteria

• Ensure full shoulder flexion range of motion

• Pain-free paddling or swimming for 30 min at moderate effort

• Pain-free single-arm push/pull tests with load 80% of contralateral side

• Full trunk extension and hip extension mobility to reduce shoulder overload

Prevention tips

• Address weak points during dry training to ensure full preparedness for long sessions

• Build gradual paddling volume before trips

• Progress to heavy isometric and eccentric loading of the rotator cuff/shoulder (to tolerance) to ensure robust and healthy tendons