How to do the Clamshell
- Lie on your side with knees bent, one hip directly above the other, head supported.
- Place a mini-band above your knees if you’re using one.
- Lift your top knee upward, rotating from your hip, keeping your feet joined.
- Stop before the hips roll, then lower the knee back down under control.
Full technique — 8 steps
- Lie on your side with hips and knees bent, one leg resting on the other, and head supported.
- Place a mini-band above your knees if using resistance, and keep your feet together.
- Set one hip directly above the other and keep your pelvis from rolling backward.
- Lightly tighten your stomach and hold a neutral lower back.
- Lift your top knee upward by rotating at the hip without separating your feet.
- Raise until your pelvis wants to move, then stop before the hips roll.
- Lower the knee back down under control to the start position.
- Complete all reps on one side, then switch sides.
Common mistakes
- Rolling the pelvis backward
- Letting the feet separate
- Opening higher with low back
- Turning it into a side plank
Form cues
- Lift knee, not foot
- Keep feet together
- Stop before hips roll
- Feel outer glute working
Substitutes by equipment
Same muscles, same movement — pick the version you have the gear for.
No equipment
- Fire Hydrant Same level
- Fire Hydrant Circles Same level
Dumbbells
Where to start and where to go next
Same muscles, same movement. Too hard for now — step down; once it gets easy — step up.
- This exercise Clamshell
- Harder Side Lying Hip Abduction
- Harder Prone Mini Band Hip Abduction
Quick answers
What muscles does the Clamshell work?
Primary: Hip abductors 8/10, Glutes 9/10.
When should I do the Clamshell in a workout?
Warm-up. Done at the start to get the body ready. ≈ 5 min with rest.
How many sets and reps of the Clamshell?
Muscle growth: 3–4 sets of 10–15 reps, rest 1 min, 3 reps in reserve. Endurance: 2–3 sets of 15–20 reps, rest 45 s, 3–4 reps in reserve.
What can I do instead of the Clamshell?
No equipment: Fire Hydrant, Fire Hydrant Circles. Dumbbells: Standing Dumbbell Hip Abduction.
What is a harder version of the Clamshell?
Side Lying Hip Abduction (15% of bodyweight), Prone Mini Band Hip Abduction (Beginner).
