Exercise guide
Dumbbell Straight Arm Crunch
- Intermediate
- Isolation
- Rep-based
- Waist
This exercise targets the upper rectus abdominis by adding a vertical load, increasing resistance throughout the crunching motion while stabilizing the core. It effectively isolates the abdominal wall by removing momentum and keeping the weight directly over the center of gravity.
Reviewed by the Crucible Fit team · Updated June 2026
Muscles worked
Setup
- Lie flat on your back on a mat with your knees bent and feet flat on the floor, hip-width apart.
- Grasp a single dumbbell with both hands, holding it by the sides of the weight or with a secure palms-in grip.
- Extend your arms fully toward the ceiling, positioning the dumbbell directly over your chest.
How to do it
- Exhale and contract your abs to lift your head, neck, and shoulder blades off the floor, pushing the dumbbell straight up toward the ceiling.
- Keep your arms locked and perfectly vertical throughout the entire movement; do not swing the weight forward toward your knees.
- Inhale as you slowly lower your upper body back to the starting position with a controlled 2-second tempo, keeping the weight elevated.
Form checklist
- Keep your lower back pressed firmly into the floor throughout the entire rep.
- Ensure the dumbbell moves in a straight vertical line rather than an arc.
- Maintain a small gap between your chin and chest to avoid pulling with your neck.
- Keep your elbows locked to ensure the core, not the arms, is doing the work.
Pro tips
- Focus on 'sliding' your ribcage toward your pelvis rather than just lifting your head to maximize abdominal shortening.
- Pause for a full second at the peak of the contraction to emphasize the mind-muscle connection with the upper abs.
Make it harder
- Lift your feet off the floor into a 'tabletop' position (90-degree hip and knee angle) to increase stability demands.
- Perform the movement on a decline bench to significantly increase the range of motion and time under tension.
Frequently asked
- What muscles does the dumbbell straight arm crunch work?
- The dumbbell straight arm crunch primarily targets the abs and obliques, and also works the erector spinae as secondary muscles.
- What equipment do you need for the dumbbell straight arm crunch?
- The dumbbell straight arm crunch uses dumbbell.
- Is the dumbbell straight arm crunch good for beginners?
- The dumbbell straight arm crunch is rated intermediate. Build a base with simpler variations first, then progress to it with light load and strict form.