Why Does My Shoulder Hurt When I Swim? Causes and Solutions

Swimming is supposed to be gentle on the joints, but shoulder pain is extremely common among swimmers. The repetitive overhead motion combined with the unique demands of pulling through water creates specific challenges for the shoulder.

Common Causes of Shoulder Pain When Swimming

Swimmer's Shoulder (Impingement)

The rotator cuff tendons get pinched during the repetitive overhead motion of swimming strokes.

What it feels like:

• Pain at front or top of shoulder
• Worse during the catch and pull phase
• Aching after swimming
• Pain when sleeping on that side

What causes it:

• High training volume
• Poor stroke technique
• Weak rotator cuff
• Tight chest and lats
• Poor scapular control

Rotator Cuff Tendinitis

The rotator cuff muscles become inflamed from the repetitive demands of swimming.

What it feels like:

• Deep shoulder ache
• Weakness with certain movements
• Pain that builds during practice
• Stiffness in the morning

What causes it:

• Overuse and high yardage
• Insufficient recovery
• Muscle imbalances
• Poor technique

Shoulder Instability

The repetitive overhead motion can stretch ligaments, leading to excessive shoulder movement.

What it feels like:

• Feeling of looseness or slipping
• Pain in certain positions
• Apprehension with arm position
• May have "dead arm" episodes

What causes it:

• Repetitive stretching of capsule
• High volume training
• Hypermobility
• Previous injuries

Labral Issues

The labrum cartilage can fray or tear from repetitive swimming stress.

What it feels like:

• Deep shoulder pain
• Catching or clicking
• Pain with specific movements
• Gradual worsening

What causes it:

• Repetitive overhead motion
• Impingement over time
• Instability
• Forceful pulling

Muscle Imbalances

Swimming develops some muscles while neglecting others, creating imbalances.

What it feels like:

• Rounded shoulder posture
• Tight chest and lats
• Weak external rotators
• Pain with non-swimming activities too

What causes it:

• Swimming as primary exercise
• Not addressing imbalances
• High volume internal rotation (pulling)
• Neglecting external rotators

How to Fix Shoulder Pain from Swimming

1. Address Stroke Technique

Poor technique multiplies shoulder stress with every stroke.

Common technique errors:

• Hand entry crossing midline: Increases impingement
• Thumb-first entry: Internally rotates shoulder
• Dropped elbow during catch: Stresses anterior shoulder
• Over-rotation: Creates instability
• Head position too high: Forces compensations

Get a stroke analysis from a qualified coach if pain persists.

2. Strengthen the Rotator Cuff

Strong rotator cuff muscles protect the shoulder during swimming.

Key exercises:

• External rotation with band: Elbow at side, rotate out. 3 sets of 15.
• Side-lying external rotation: Light weight, rotate upward. 3 sets of 12.
• 90/90 external rotation: Arm at 90 degrees, rotate. 3 sets of 12.
• Prone Y-T-W: Face down, lift arms in positions. 3 sets of 10 each.

3. Build Scapular Stability

Proper shoulder blade control is essential for healthy swimming.

Key exercises:

• Scapular push-ups: Push-up position, protract and retract. 3 sets of 15.
• Face pulls: Pull band to face, squeeze at end. 3 sets of 15.
• Rows with squeeze: Emphasize scapular retraction. 3 sets of 15.
• Wall slides: Back to wall, slide arms up and down. 3 sets of 12.

4. Stretch Tight Muscles

Swimming tightens the chest, lats, and internal rotators.

Key stretches:

• Doorway pec stretch: Arm at various heights on frame. Hold 30 seconds each.
• Lat stretch: Arm overhead, lean away. Hold 30 seconds each side.
• Sleeper stretch: Side-lying, push forearm down. Hold 30 seconds each side.
• Cross-body stretch: Pull arm across chest. Hold 30 seconds each side.

5. Manage Training Load

Volume is often the root cause.

Strategies:

• Reduce yardage when pain flares
• Include rest days
• Vary strokes (mix in backstroke, kick sets)
• Don't increase volume more than 10% per week
• Include dryland training days

6. Warm Up Properly

Cold shoulders are vulnerable shoulders.

Pre-swim routine:

• Arm circles and swings
• Band external rotation
• Scapular exercises
• Easy swimming before main set
• Avoid diving in cold

When to See a Doctor

Seek professional evaluation if:

• Pain is severe or worsening
• You have significant weakness
• Shoulder feels unstable
• Symptoms persist despite 3-4 weeks of modifications
• Pain affects daily activities
• You have numbness or tingling

Prevention Strategies

Build habits:

1. Strengthen rotator cuff year-round
2. Stretch chest and lats daily
3. Include technique work in practice
4. Progress training gradually
5. Cross-train with dryland exercises
6. Don't ignore early warning signs

The Bottom Line

Shoulder pain from swimming usually stems from impingement, rotator cuff overuse, or muscle imbalances—all made worse by high volume and poor technique. The fix combines addressing technique, strengthening the rotator cuff and scapular stabilizers, stretching tight muscles, and managing training load.

Start by reducing volume and analyzing technique—these address the most common causes. Add the strengthening and stretching work for long-term shoulder health. Most swimmer's shoulder improves within 4-6 weeks of proper management.

If pain persists or you have instability, see a sports medicine specialist familiar with swimming injuries.