Stability Ball Oblique Crunch
The Stability Ball Oblique Crunch is a core isolation exercise performed sideways on an exercise ball to target the internal and external obliques. By utilizing an unstable surface, this movement increases core engagement and improves lateral spinal stability compared to floor-based variations.
Since core stability is heavily influenced by central nervous system fatigue, the AI analyzes your HRV and sleep quality to determine if you have the coordination required for this stability-focused movement. If you report lower back tightness or fatigue from previous heavy compound lifts, the app can instantly regress this to a floor-based alternative to protect your spine. Over time, it learns the specific rep ranges that trigger your best oblique activation without causing you to compensate with your hips.
Form Cues
- Brace your feet firmly against a wall or sturdy object for stability
- Position the ball directly under your waist and lower rib cage
- Crunch your top rib cage down toward your top hip bone
- Exhale sharply as you crunch up to maximize muscle contraction
- Control the descent slowly to resist gravity
- Don't pull on your head or neck with your hands
- Don't bounce off the ball to generate momentum
- Don't let your hips roll forward or backward during the set
- Don't rush the eccentric (lowering) phase of the movement
Common Mistakes
- Pulling on the neck
- Inconsistent hip alignment
- Using momentum to crunch up
- Placing the ball too high on the torso
- Limited range of motion
Muscles Worked
This exercise primarily isolates the internal and external obliques, which are crucial for rotational power, lateral flexion, and spinal stability. It also engages the deep transverse abdominis and rectus abdominis to maintain balance on the unstable ball, providing a comprehensive core workout.
Primary
Secondary
Get Personalized Coaching for Stability Ball Oblique Crunch
Don't guess your way through weights or workouts. Download Iridium for automatic, AI-powered coaching that adapts to your recovery and goals.