Cross-Body Crunch

Cross-Body Crunch is a strength – torso rotation toward the opposite knee exercise involving Rectus abdominis. Use these steps to learn the movement and work with your coach to choose a suitable level.

Last updated: 2026-10-31 · DynPerformance

Primary muscles: Rectus abdominis
Secondary muscles: Iliopsoas, Transversus abdominis
Exercise type: Strength – torso rotation toward the opposite knee

Exercise technique

Base
Lie on your back with knees bent and feet on the floor.
Hands
Place your hands behind your head without applying pressure.
Knee
Bring one knee toward the opposite shoulder.
Torso
Lift the opposite shoulder and curl your ribs diagonally.
Approach
Focus on bringing the shoulder and knee together rather than the elbow.
Return
Lower your shoulder and foot with control.
Sides
Continue alternating the other knee and shoulder.

Key technique points

Generate rotation through your rib cage.
Keep your supporting foot on the floor.
Curl without unnecessarily rotating your pelvis.
Do not pull your neck with your hands.
Use the same range on each side.
Exhale as you close.

Common mistakes

Moving only the elbow

Do not fold your arm toward the knee without lifting your shoulder.

Swinging the knee

Do not rely on leg speed to produce the crunch.

Pressing the head

Do not force your neck diagonally with your hand.

Lifting the supporting foot

Do not turn this opposite-knee variation into a bicycle movement.

Rolling the hips

Do not roll your whole pelvis sideways as the knee approaches.

Falling back

Do not drop your back to the floor without slowing it with your abdominals.

Frequently asked questions