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Balance Trainer Crunch
A core exercise on an unstable surface like a BOSU trainer that targets the rectus abdominis and obliques to build stability and strength; enhances balance and coordination for functional training.
About Exercise
Equipment
Balance Trainer
Difficulty
2/5 • Intermediate
Primary Muscle Groups
Abs
Secondary Muscles
Hip Flexors, Lower Back
Popularity Score
6
Goals
Training Style
Setup Requirements
Requires Rack
No
Requires Bench
No
Requires Spotter
No
Space Needed
Small
Noise Level
Low
Muscle Breakdown
View Muscle MapAbs
10/10Rectus Abdominis, Transverse Abdominis
Obliques
7/10External Obliques, Internal Obliques
Hip Flexors
5/10Iliopsoas
Lower Back
3/10Erector Spinae
Programming
Typical Rep Range
10-25 reps
Rest Between Sets
30-60 seconds
How to Perform
Sit on the balance trainer with feet flat on the ground, knees bent at 90 degrees. Walk feet forward until lower back is supported, shoulders relaxed, and head aligned with spine.
- Engage core by drawing navel toward spine.
- Exhale and curl upper body toward knees, lifting shoulder blades off the trainer.
- Hold briefly at the top, squeezing abs.
- Inhale and slowly lower upper body to start position.
- Maintain control and avoid momentum.
Coaching Tips
Form Cues
- Curl from abs, not neck.
- Keep chin off chest.
- Drive from hips.
- Stay balanced on trainer.
- Ribs toward hips.
Breathing
Exhale during the upward crunch; inhale as you lower. Brace core throughout.
Tempo
2-1-2
Range of Motion
Lift until shoulder blades clear the trainer; lower until mid-back contacts without arching.
Safety
Safety Notes
- Consult professional for back issues.
- Use stable, inflated trainer.
- Avoid if acute injury.
- Maintain spinal alignment.
- Perform slowly to prevent strain.
Spotting
Not required; self-supported bodyweight exercise.
Common Mistakes
- Pulling on neck with hands.
- Using momentum to swing up.
- Excessive lower back arch.
- Head jutting forward.
- Feet lifting off ground.
When to Avoid
- Acute back pain
- Neck injuries
- Recent abdominal surgery
Flexibility Needed
- Shoulder flexion
- Hip flexion
- Ankle stability
Build Up First
- Basic crunch form
- Core engagement awareness
Also known as
BOSU Crunch, Stability Ball Crunch, Unstable Surface Crunch, Balance Ball Abdominal Crunch, BOSU Abdominal Crunch
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