The clamshell is "ideal" for your gluteus maximus, Jason said. It also activates your gluteus medius, a muscle just underneath your gluteus maximus that extends slightly into your lower back, said Jillian Lorenz, NASM-certified personal trainer and co-founder of the Barre Code. You'll get stronger hip and pelvis stability, she explained, something that you might lack when sitting for long periods of time.
- Lie on your side with one leg stacked on top of the other in a position similar to the fetal position. Your knees should be bent at a 45-degree angle.
- Rest your head on your lower arm.
- Brace your abs or draw your belly button in toward your spine.
- Keeping your feet touching, raise the knee of your top stacked leg as high as you can. Be sure not to shift your hips or pelvis. Your lower leg should remain in contact with the floor.
- Pause for a one count, then return your upper leg to the starting position (on top of the other leg).
- Then roll over so you are on your other side. Repeat the above steps for the opposite side.