Medicine Ball Crunch On Stability Ball

Muscles worked

Setup

1. Sit on the stability ball and walk your feet forward until the ball supports your lower back (lumbar spine).
2. Place your feet flat on the floor, hip-width apart, with knees bent at a 90-degree angle.
3. Hold the medicine ball firmly against your chest or slightly above your torso.

How to do it

1. Inhale and slowly lower your upper back over the curve of the ball to achieve a full stretch in the abdominals.
2. Exhale and contract your core to curl your shoulders toward your hips, lifting your upper back off the ball.
3. Pause at the peak of the contraction for one second, focusing on squeezing the abs.
4. Lower yourself back to the starting position with a controlled 2-second eccentric phase.

Form checklist

• Keep your chin tucked toward your chest to prevent neck strain.
• Ensure the ball remains stationary under your lower back throughout the set.
• Maintain a firm foot plant to prevent sliding or losing balance.
• Focus on curling the ribs toward the pelvis rather than pulling with your arms.

Pro tips

• For maximum muscle fiber recruitment, emphasize the stretch at the bottom by wrapping your spine around the ball's contour.
• Keep the medicine ball stationary relative to your torso to ensure the abs are doing the work, not your shoulders.

Make it harder

• Hold the medicine ball with arms fully extended overhead to increase the lever arm and resistance.
• Narrow your foot stance to a single point of contact to significantly increase the stability challenge.

Frequently asked

What muscles does the medicine ball crunch on stability ball work?

The medicine ball crunch on stability ball primarily targets the abs and obliques, and also works the erector spinae, glutes, and quadriceps as secondary muscles.

What equipment do you need for the medicine ball crunch on stability ball?

The medicine ball crunch on stability ball requires no equipment — just your body weight.

Is the medicine ball crunch on stability ball good for beginners?

The medicine ball crunch on stability ball is rated intermediate. Build a base with simpler variations first, then progress to it with light load and strict form.

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