Ab Coaster
Machine-guided kneeling crunch that targets rectus abdominis and obliques to build core strength and stability; commonly scaled by adding weight plates for progression.
About Exercise
Equipment
AB Coaster Machine
Difficulty
2/5 • Beginner
Primary Muscle Groups
Abs
Secondary Muscles
Hip Flexors
Popularity Score
5
Goals
Training Style
Setup Requirements
Requires Rack
No
Requires Bench
No
Requires Spotter
No
Space Needed
Medium
Noise Level
Low
Muscle Breakdown
View Muscle MapAbs
9/10Rectus Abdominis
Obliques
7/10External Obliques, Internal Obliques
Hip Flexors
4/10Iliopsoas
Programming
Typical Rep Range
10-20 reps
Rest Between Sets
30-60 seconds
How to Perform
Kneel on the padded seat of the Ab Coaster Machine with feet hooked behind if available. Place forearms on arm pads and grasp handles to stabilize upper body.
- Engage core by pulling belly button to spine.
- Exhale and contract abs to glide knees forward and upward toward chest.
- Squeeze abs at top of motion.
- Inhale and slowly lower knees back to start position.
- Maintain control without momentum.
Coaching Tips
Form Cues
- Drive with abs
- Keep upper body stable
- Squeeze at top
- Control the descent
- Avoid swinging
Breathing
Exhale during the upward contraction; inhale on the controlled return.
Tempo
2-1-2
Range of Motion
Start with knees extended at bottom of track; lift until knees approach chest without rounding lower back.
Safety
Safety Notes
- Consult physician for back or neck issues
- Ensure stable surface
- Keep limbs clear of moving parts
- Do not exceed weight limits
- Stop if pain occurs
Spotting
Not required; machine provides guided path and stability.
Common Mistakes
- Using momentum to lift
- Rounding lower back
- Pulling with arms
- Crashing seat at bottom
- Leaning forward
When to Avoid
- Acute lower back pain
- Neck injuries
- Hernias
Flexibility Needed
- Adequate hip flexion
- Shoulder stability for gripping
Build Up First
- Basic core engagement awareness
- Familiarity with kneeling posture
Also known as
Ab Coaster, Kneeling Ab Machine, Core Glider
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