Exercise guide
Dumbbell Side Lying Internal Rotation On A Bench
- Beginner
- Isolation
- Rep-based
- Back
- Shoulders
- Upper arms
This isolation exercise specifically targets the subscapularis and pectoralis major, strengthening the internal rotators of the shoulder to improve joint stability and prevent injury.
Reviewed by the Crucible team · Updated June 2026
Muscles worked
Setup
- Lie on your side on a flat bench, supporting your head with your top hand or a small pillow.
- Hold a light dumbbell in the hand of your bottom arm (the arm closest to the bench).
- Bend your bottom elbow to 90 degrees and tuck it firmly into your side, allowing your forearm to hang off the edge of the bench.
- Stack your hips and shoulders vertically to ensure a stable base.
How to do it
- Start with your forearm hanging down toward the floor, maintaining the 90-degree bend in your elbow.
- Exhale as you rotate your forearm upward toward your torso, pulling the dumbbell toward your stomach while keeping the elbow pinned to your side.
- Inhale as you slowly lower the dumbbell back to the starting position using a controlled 3-second eccentric tempo.
- Complete the set on one side before flipping over to work the opposite arm.
Form checklist
- Keep the working elbow glued to your ribs throughout the entire movement.
- Maintain a consistent 90-degree angle at the elbow joint.
- Avoid rotating your torso or hips to help lift the weight.
- Ensure the movement occurs only at the shoulder joint, not the wrist.
Pro tips
- Place a small rolled-up towel between your elbow and your side; if the towel falls, your elbow has drifted too far from your body.
- Focus on the 'mind-muscle connection' by visualizing the humerus (upper arm bone) rotating within the shoulder socket rather than just moving the hand.
Make it harder
- Add a 2-second isometric squeeze at the top of the movement when the dumbbell is closest to your torso.
- Slow the eccentric (lowering) phase to 5 seconds to increase time under tension for the rotator cuff.
Frequently asked
- What muscles does the dumbbell side lying internal rotation on a bench work?
- The dumbbell side lying internal rotation on a bench primarily targets the pectorals and rotator cuff, and also works the biceps and deltoids as secondary muscles.
- What equipment do you need for the dumbbell side lying internal rotation on a bench?
- The dumbbell side lying internal rotation on a bench uses dumbbell.
- Is the dumbbell side lying internal rotation on a bench good for beginners?
- Yes. The dumbbell side lying internal rotation on a bench is a beginner-friendly movement and a strong foundation to build on.