How to do it
How do you do the Banded Clamshell?
- Loop a band just above your knees and lie on your side.
- Bend your hips and knees, stacking your legs and heels.
- Keep your heels together and lift your top knee.
- Pause, then lower it slowly against the band.
- Finish your set, then switch sides.
Cues
- Keep your hips stacked, don't roll back.
- Heels stay glued together.
- Slow and steady, no swinging.
Common mistakes
- Rolling your pelvis back to lift higher.
- Letting your feet come apart.
- Rushing the reps with momentum.
Form in detail
What does good form look like?
Starting position
Lie on the left side on a mat, so the right (top) leg works. Hips bent about 45°, knees bent about 90°, legs stacked, knees together, heels together and in line with the buttocks. Hips and shoulders stacked straight up and down, the pelvis square to the floor and not rolled back. Head rests on the stretched-out bottom arm; the top hand rests on the floor in front of the chest (or on the top hip). Brace the stomach so the back stays in its natural curve. The camera faces the front of the body, so the band and both knees stay in view. The app tells users to switch sides.
The movement
Keeping the heels touching, turn the top thigh outwards to lift the right knee up and away from the left knee against the band, like a clam opening. Only the top thigh moves: the pelvis does not roll back, the trunk does not crunch and the feet stay together. Stop when the knee has opened as far as it can go without the pelvis rolling, hold briefly, then lower the knee slowly until it is just above the bottom knee, band still taut.
End position
Open: top thigh about 40° from the bottom thigh, knees about 25–30 cm apart, heels together, pelvis still stacked.
Tempo
1 s open, 1 s hold, 2 s close, no rest with the knees together.
Form in numbers
What are the angles and distances?
| Measure | Target | Good range | Sources |
|---|---|---|---|
| Band position | just above the knees | lower third of the thighs | [1][2] |
| Hip flexion | 45° | 30–60° | [3][4] |
| Knee flexion | 90° | 80–100° | [2] |
| Heels | together, in line with the buttocks | touching throughout | [1][2] |
| Pelvis | stacked, neutral (not reclined) | under 10° roll back | [1][3] |
| Trunk | still, no crunch | — | [1] |
| Head | resting on the bottom arm | neck in line with the spine | [1] |
The targets our 3D demo was built to, from the references below. Bodies differ, so treat the ranges as a guide for your own build.
For coaches
Use this demo in your clients’ programs
The Banded Clamshell is in Trainaq’s exercise library. Add it to a workout, and your client sees this demo in the free Trainaq app above the sets they log.
Sources
Sources
- NASM, The Banded Clamshell: A Simple Move for Stronger Glutes (Heather Cherry)
- Willcox and Burden 2013, J Orthop Sports Phys Ther 43(5):325–331, The influence of varying hip angle and pelvis position on muscle recruitment patterns of the hip abductor muscles during the clam exercise
- Distefano et al. 2009, J Orthop Sports Phys Ther 39(7):532–540, Gluteal muscle activation during common therapeutic exercises
