Pilates Ball Sit Up
The pilates ball sit up is a medicine ball core exercise targeting the abdominal muscles. Performing the sit-up on an unstable ball surface increases core activation and also develops balance and spinal stabilizer engagement.
How to do it
- Sit on a pilates or stability ball with feet flat on the floor, hip-width apart.
- Walk your feet forward and lean back until your lower back is supported by the ball.
- Place your hands behind your head with elbows pointed out.
- Engage your core and curl your upper body off the ball into a crunch or full sit-up.
- Slowly lower back to the starting position.
- Repeat for the desired number of repetitions.
Form cues
- Keep your feet flat on the floor
- Support your lower back firmly on the ball
- Exhale as you lift your upper body
- Keep your elbows wide and open
Breathing: Exhale as you curl up toward the ceiling, and inhale slowly as you lower yourself back to the starting position.
Common mistakes
- Pulling on your neck with your hands, which can cause strain instead of working the abs.
- Using momentum to bounce up, which reduces the active effort from your core muscles.
- Placing feet too close together, which compromises your balance on the ball.
Muscles worked
Primary: abs. Secondary: hip flexors, obliques, lower back.
Suggested sets & reps
Get fitter
3 sets × 10–12 reps, rest 60 s
Lose weight
3 sets × 12–15 reps, rest 45–60 s
Build muscle
3 sets × 8–12 reps, rest 60–90 s
Easier, harder & alternatives
Make it easier
Make it harder
Alternatives
Take care if…
- If you feel lower back discomfort, reduce your range of motion or consult a professional.
General educational guidance, not medical advice. Stop on sharp pain and check with a qualified professional if unsure.
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Start free →Frequently asked questions
What size stability ball should I use?
Choose a ball size where your knees form a comfortable 90-degree angle when you sit on it with your feet flat.
Why do I feel this in my hip flexors?
If your feet are not planted firmly or you lift too quickly, your hip flexors may take over. Slow down and focus on curling through your spine.
How often can I do this exercise?
2 to 3 times per week is plenty for recovery and core strengthening.