Bosu Ball Cable Crunch With Side Bends

Bosu Ball Cable Crunch With Side Bends is a strength – cable-resisted trunk flexion 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: Internal and external obliques, Iliopsoas
Exercise type: Strength – cable-resisted trunk flexion

Exercise technique

Setup
Place a Bosu between two low pulleys.
Position
Support your lower back on the dome and plant your feet wide.
Grip
Grasp both cables and direct your extended arms between your knees.
Curl
Maintain arm angle and curl your ribs toward your pelvis.
Open
Slowly return your back onto the Bosu.
Transition
If control remains, hold your upper body raised and move your arms to your sides.
Side reach
Reach alternately toward your heels, then release the cables under control.

Key technique points

Keep the Bosu base from sliding.
Use a wide foot base.
Keep your arms long during cable crunches.
Transition to side reaches only while balance holds.
Do not sacrifice lower-back control for exhaustion.
Match both pulley loads.

Common mistakes

Pulling with the arms

Do not gather the cables with your elbows instead of curling your abdomen.

Sliding off the Bosu

Do not move your hips too low and lose lower-back support.

Opening too far back

Do not seek uncontrolled lumbar extension over the dome.

Rushing the transition

Do not begin side heel reaches before establishing balance.

Unequal loads

Do not let the cables pull your torso differently.

Swinging quickly

Do not sustain the side bend through torso momentum.

Frequently asked questions