Clamshell
A side-lying exercise opening the top knee while keeping the feet together. It targets the gluteus medius and hip external rotators.
Primary muscles
- Gluteus Medius
Secondary muscles
- Hip Abductors
- Glutes (Gluteus Maximus)
- Sets
- 2–3
- Reps
- 15–20 per side
- Rest
- 30–45s
How to perform
Main muscles working (thicker lines)
Starting position
Lie on your side with hips and knees bent about 45 degrees, feet together and head supported on your lower arm. Optionally add a mini band above the knees.
Keep your feet together and hips stacked.
Lift your top knee as far as you can without rolling your pelvis back.
Pause at the top.
Lower slowly and repeat, then switch sides.
Breathing: Exhale as you open, inhale as you close.
Coaching tips
Feet stay together
Hips stacked
Small, controlled range
Common mistakes
Rolling the pelvis backward
Lifting the feet apart
Rushing reps
Safety notes
Keep the range small enough that your pelvis doesn't rotate.
This information is general fitness guidance, not medical advice. Stop if you feel pain and consult a qualified professional.