Side Lying External Rotation
- Músculo objetivo
- —
- Equipamiento
- Body weight
- Parte del cuerpo
- Shoulders
- Tipo
- Strength
Side Lying External Rotation is a bodyweight rotator cuff exercise performed lying on your side, rotating your forearm upward against gravity with the elbow bent at 90°. It targets the infraspinatus and teres minor, building external rotation strength and improving shoulder joint stability and long-term health.
Cómo hacer el Side Lying External Rotation
- 1Lie on your side on a firm surface with your legs stacked and your head resting on your lower arm or a pillow.
- 2Bend your top elbow to 90° and press it firmly against your waist so the forearm points straight ahead, parallel to the floor.
- 3Keep your elbow pinned to your side throughout the movement — this is your fixed anchor point.
- 4Slowly rotate your forearm upward toward the ceiling, pivoting at the elbow, until your forearm is vertical or slightly past vertical.
- 5Pause briefly at the top, squeezing the back of the shoulder.
- 6Lower your forearm back to the starting position in a slow, controlled manner — do not let it drop.
- 7Complete all reps on this side, then roll over and repeat on the opposite side.
Consejos de técnica
- Keep the elbow pinned firmly to your waist at all times — if it lifts away, the rotator cuff disengages and larger muscles take over.
- Use a slow, deliberate tempo: aim for 2 seconds up and 3 seconds down to maximize time under tension on the rotator cuff.
- Avoid rolling your torso backward as the arm rises — if you need to rotate your body to complete the rep, reduce the range of motion.
- Work through a full, pain-free arc; stopping short limits the training stimulus on the infraspinatus and teres minor.
- If the floor limits your range at the bottom, place a small folded towel under your elbow to allow the forearm to hang slightly below parallel at the start.
Errores comunes
- Letting the elbow drift away from the body: this shifts the load off the rotator cuff onto the deltoid and reduces the exercise's therapeutic and strengthening value.
- Using momentum or swinging the arm: a fast, uncontrolled rotation bypasses the small rotator cuff muscles entirely and increases the risk of impingement.
- Rolling the torso backward to gain range: torso rotation is compensation, not shoulder external rotation — it means you have exceeded your current mobility.
- Stopping the forearm before it reaches vertical: shortening the range keeps the rotator cuff in a less-challenging portion of the movement and slows progress.
- Holding the breath: the rotator cuff requires stable intra-thoracic pressure; exhale on the way up and inhale on the controlled descent.
Preguntas frecuentes
What muscles does the Side Lying External Rotation work?
The exercise primarily trains the infraspinatus and teres minor, two of the four rotator cuff muscles responsible for externally rotating the humerus. The posterior deltoid assists as a synergist. The rotator cuff as a whole also works isometrically to center the humeral head in the socket throughout the movement.
Is the Side Lying External Rotation good for shoulder pain or impingement?
Strengthening the external rotators is a cornerstone of shoulder impingement rehabilitation, as weakness in these muscles allows the humeral head to migrate upward and compress the subacromial space. That said, you should perform this exercise pain-free and within a comfortable range. If you have an existing shoulder injury, confirm with a physiotherapist that this movement is appropriate for your stage of recovery before starting.
How many reps and sets should I do?
For shoulder health and injury prevention, 2–3 sets of 12–20 reps per side with a slow, controlled tempo is a common starting point. Because there is no added resistance in the bodyweight version, higher rep ranges and strict form matter more than low rep counts. Progress by slowing the eccentric phase further or adding isometric holds at the top before eventually considering a light resistance band or small weight.
What is the difference between internal and external shoulder rotation?
Internal rotation moves the forearm downward and across the body (think tucking your hand behind your back), driven primarily by the subscapularis, pectoralis major, and latissimus dorsi. External rotation moves the forearm upward and away from the body, driven by the infraspinatus and teres minor. Most people are internally dominant due to posture and daily activities, making external rotation training important for muscular balance and joint health.
How do I progress the Side Lying External Rotation once bodyweight becomes too easy?
Once you can complete 3 sets of 20 reps per side with strict form and a 3-second eccentric, you can increase difficulty by adding a long isometric hold at the top of each rep, slowing the eccentric to 4–5 seconds, or transitioning to a version performed with a light resistance band looped around the wrist. A standing cable or band external rotation at 90° of abduction is a further progression for advanced shoulder strength work.
