Ball Crunch (on stability ball)
The Ball Crunch (on stability ball) primarily works the Rectus Abdominis, with secondary activation of the External Obliques. It is a bodyweight isolation exercise at intermediate difficulty.
The Ball Crunch (on stability ball) is an intermediate isolation exercise requiring no equipment, following a flexion movement pattern. It primarily targets the Rectus Abdominis, with secondary engagement of the External Obliques. This is a bilateral pulling movement, engaging both sides of the body simultaneously.
A bodyweight isolation pull exercise targeting the Rectus Abdominis.
| Equipment | Bodyweight |
|---|---|
| Difficulty | Intermediate |
| Type | Isolation |
| Movement | Flexion |
| Force | Pull |
| Laterality | Bilateral |
| Primary | Rectus Abdominis |
| Secondary | External Obliques |
Muscles Worked
The Rectus Abdominis is the primary mover, taking on the bulk of the workload throughout the full range of motion. The External Obliques assists as a secondary mover, contributing to force production without bearing the primary load.
Primary Muscles
- Primary Muscle Rectus Abdominis (core)
Secondary Muscles
- Secondary Muscle External Obliques (core)
How to Perform
Preparation
- Sit on exercise ball.
- Walk forward on ball and lie back on ball with shoulders and head hanging off and knees and hips bent.
- Gently hyperextend back on contour of ball.
- Place hands behind neck or beside head.
Execution
- Flex waist to raise upper torso.
- Return to original position.
- Repeat.
Comments
- Certain individuals may need to keep their neck in neutral position with space between their chin and sternum.
- Some individuals may experience low back discomfort if hips are not bent so they must use smallerball sizeor lower their hip position on ball.
- SeeSpot Reduction Myth.
Tips & Common Mistakes
- Control the eccentric phase — the lowering portion drives significant muscle development.
- Avoid momentum; focus on feeling the target muscle work through the full range.
- Full range at both ends maximizes stretch at the bottom and contraction at the top.
Programming Suggestions
Adapt your sets and reps to your training goal.
| Strength | 3–4 sets × 6–8 reps at 75–85% 1RM with 90–120 seconds rest. |
|---|---|
| Hypertrophy | 3–4 sets × 10–15 reps at 60–75% 1RM with 60–90 seconds rest. |
| Endurance | 2–3 sets × 15–25 reps at 40–60% 1RM with 30–45 seconds rest. |
Alternative Exercises
These exercises target the same primary muscles (Rectus Abdominis) and can be substituted based on your equipment or variation preferences.
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