Crunch
Auto DetectedBodyweight exercise that targets the rectus abdominis to build core strength and stability; performed lying on the floor with knees bent, emphasizing controlled spinal flexion.
About Exercise
Equipment
Difficulty
1/5 • Beginner
Primary Muscle Groups
Abs
Secondary Muscles
Obliques, Abs
Popularity Score
10
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
Obliques
5/10External Obliques, Internal Obliques
Abs
4/10Transverse Abdominis
Programming
Typical Rep Range
10-25 reps
Rest Between Sets
30-60 seconds
How to Perform
Lie on your back on the floor or mat with knees bent, feet flat hip-width apart, and hands crossed over your chest.
- Engage core by drawing belly button to spine.
- Exhale and curl upper back off floor, lifting shoulders toward knees.
- Pause briefly at top, squeezing abs.
- Inhale and slowly lower upper back to floor.
- Maintain lower back contact with ground throughout.
Coaching Tips
Form Cues
- Curl ribs toward hips.
- Keep neck neutral.
- Drive with abs, not momentum.
- Maintain tension in core.
Breathing
Exhale during the lift to contract abs; inhale as you lower.
Tempo
3-1-1
Range of Motion
Curl until shoulder blades lift off floor; lower until upper back touches down, keeping lower back pressed flat.
Safety
Safety Notes
- Avoid if acute back or neck pain exists.
- Stop if lower back lifts off floor.
- Consult professional for pre-existing conditions.
Spotting
Not required; self-supported bodyweight exercise.
Common Mistakes
- Pulling on neck.
- Arching lower back.
- Using momentum for lift.
- Tucking chin too far.
When to Avoid
- Acute neck strain
- Lower back injury
- Herniated disc
Flexibility Needed
- Basic spinal flexion
- Shoulder mobility for hand position
Build Up First
- Core engagement awareness
Also known as
Ab Crunch, Standard Crunch, Floor Crunch
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