Clamshell

Which muscles does it train?

Equipment needed

How to perform it

Isolation work is usually trained in a higher rep range: 2 to 4 sets of 10 to 15 reps with 45 to 90 seconds of rest, performed under control.

Execution and technique cues

• Lie on your side with hips and knees bent to approximately 45 degrees, feet stacked, and spine in a neutral position.
• Rest your head on the lower arm and place the upper hand lightly on the hip to monitor and prevent pelvic rotation during the movement.
• Raise the top knee as high as possible without rotating the pelvis, rotating only at the hip joint and not through the lumbar spine.
• Hold the top position briefly, then lower the knee under control and prevent the hip from tipping forward between reps.

Common mistakes

• The pelvis rocks backward as the knee lifts, reducing gluteus medius activation and turning the movement into lumbar rotation.
• Using an excessive range of motion that is achieved through lumbar compensation rather than genuine hip abduction mobility.
• Placing a resistance band too far up the thigh, shortening the lever arm and reducing the training stimulus on the gluteus medius.

Frequently asked questions

Should I use a resistance band for the Clamshell?

Yes, a band placed just above the knees increases abduction resistance and improves neuromuscular activation of the gluteus medius. Start without a band to learn the movement pattern first.

How many reps are appropriate for the Clamshell?

Higher rep ranges of 15 to 25 per side are common because it is a low-load isolation exercise. Controlled execution without pelvic compensation matters more than hitting a specific rep count.

Related exercises