Exercise Guide
How to do dumbbell lying triceps extension
Master the setup, range of motion, and tempo for safer, more effective reps.
Overview
The Dumbbell Lying Triceps Extension is a classic isolation exercise. Unlike a press, which uses your chest and shoulders, this move forces the triceps to do all the heavy lifting.
By using dumbbells instead of a barbell, you allow your wrists to move more naturally and ensure that your stronger arm isn't doing all the work. It’s a must-have for anyone looking to fill out their sleeves or improve their lockout strength for bench pressing.
Why Use It
- Directly targets all three heads of the triceps for maximum arm growth.
- Easier on the wrists than the barbell version thanks to the neutral grip.
- Identifies and fixes strength imbalances between your arms.
When to Use It
Perform this after your main pressing movements (like Bench Press or Overhead Press) when your triceps are already warm but not completely exhausted.
Stats
Instructions for Proper Form
Setup
- The Position: Lie flat on your back on a bench. Plant your feet firmly on the ground.
- The Grip: Hold the dumbbells directly above your shoulders with your palms facing each other.
Execution
- The Bend: Keeping your upper arms perfectly still, bend your elbows to lower the dumbbells toward your temples.
- The Stretch: Stop when the dumbbells are just past your ears. You should feel a deep stretch in the back of your arms.
- The Extension: Use your triceps to straighten your arms back to the starting position. Squeeze your triceps hard at the top.
Pro-Tip
Imagine your upper arms are glued in place. The only thing that should move is your forearm. If your elbows move back and forth, you're using your shoulders, not your triceps!
Common Mistakes
- Flaring Elbows: Letting your elbows point out to the sides puts stress on the joints and takes work off the triceps. Keep them tucked!
- Moving the Upper Arm: If your upper arm moves toward your face, you're turning this into a pullover. Keep those arms vertical.
- Going Too Heavy: This is an isolation move. If you have to swing the weights, they are too heavy.
Mistakes by Level
Beginner
- Letting the dumbbells drift apart or clank together.
- Moving too fast and losing control of the weights near the face.
Intermediate
- Allowing the elbows to flare out as the set gets harder.
- Not reaching a full range of motion at the bottom.
Advanced
- Using 'body English' to finish the last few reps.
- Losing the 'squeeze' at the top of the movement.
Mechanics
Use these setup and execution anchors to keep the rep organized, repeatable, and easier to progress.
Movement Pattern
Isolation
Body Position
Other
Load Style
Bilateral
Muscles Worked
Primary
- Triceps
Secondary
None emphasized.
Stabilizers
- Shoulders
- Forearms
- Core
Setup Requirements
- Lie flat on a bench with your feet pressed firmly into the floor for stability.
- Hold a dumbbell in each hand directly over your chest with your arms straight.
- Turn your palms to face each other (neutral grip).
- Lock your shoulder blades down into the bench.
Form Checklist
- Are my elbows pointing forward rather than flaring out to the sides?
- Is my upper arm staying vertical and still?
- Am I moving only at the elbow joint?
- Are the weights moving in a controlled arc?
Range of Motion
Lower the dumbbells by bending only at the elbows until they are near your ears or temples, then extend back to the start.
Breathing Pattern
Inhale as you lower the weights toward your head; exhale as you straighten your arms back up.
Tempo Guidance
Focus on a slow, controlled 3-second lowering phase to feel the stretch in the triceps.
Caution Notes
- If you have elbow pain, try lowering the weights slightly further behind your head rather than toward your forehead.
Programming
Treat these guidelines as practical programming defaults, then scale load, volume, and frequency to match the rest of the training week.
Best For
- Isolating the triceps for muscle growth.
- Improving lockout strength for big presses.
- Adding variety to arm training.
Goal Tags
Rep Ranges
- 10-15 reps for the best muscle-building stimulus.
- 8-12 reps if you are focusing on strength.
- 15-20 reps for a finishing 'pump' at the end of a workout.
Set Guidance
3-4 sets is usually plenty for this isolation move.
Rest Guidance
60-90 seconds. You want your triceps to be recovered enough to maintain good form.
Frequency
Can be performed 2-3 times per week, ideally on 'Push' or 'Arm' days.
Pairings
- Pair with Bicep Curls for a classic 'Antagonist' arm superset.
- Pair with Pushups to completely fatigue the triceps.
Audience Notes
- Beginners should start light to ensure the elbows stay tucked.
- Advanced lifters can perform these on a slight incline or decline to change the angle of the stretch.
Substitution Targets
- EZ-Bar Skull Crushers if you prefer a single bar.
- Cable Overhead Extensions if you want constant tension.
Variations
Use progressions to increase difficulty when you master the movement, and regressions if you struggle with proper form or face mobility limitations.
Regressions
Single Dumbbell Extension
Holding one dumbbell with both hands is more stable and easier to control.
Best for: Beginners learning the elbow path.
Progressions
Decline Dumbbell Extension
Lying on a decline bench increases the range of motion and the stretch on the triceps.
Best for: Advanced lifters looking for more growth.
FAQ
Common Questions
Why are they called Skull Crushers?
Because if you lose control of the weight, it's headed straight for your forehead! Always use a weight you can control and consider a spotter if going heavy.
My elbows hurt when I do these. What should I do?
Try lowering the weights slightly 'behind' your head rather than to your forehead. This often takes the pressure off the elbow joint.
Alternatives
Start with the closest related options, then browse fallback alternatives that keep the same primary training focus.