Skull Crusher
Lying triceps extensions — named for the mistake, built on the control.
Setup
- Lying down, bar pressed over the chest.
- Elbows set slightly back toward your head — they stay there.
How To Do It
- Bend only the elbows, lowering to your forehead or just behind.
- Extend back to lockout without the elbows drifting.
Breathing
Inhale down, exhale up.
Common Mistakes
- Elbows flaring and drifting — the upper arm is a statue.
- Going too heavy — the name is a warning label.
Programming It
Three sets of 8-12.
Why This Exercise Works
Lowering to the forehead keeps the upper arm angled back slightly, which holds the long head of the triceps under stretch through the whole rep. That is what makes it more productive than a pushdown, and also what makes it hard on the elbows if you go heavy.
Where You Should Feel It
A stretch through the long head of the triceps as the bar lowers behind the forehead. Elbow ache is the common complaint and usually means the load is too heavy.
Where It Fits in a Program
Lying triceps extensions — named for the mistake, built on the control. It deserves the first slot and the longest rest periods you are willing to take.
Progressing and Regressing It
To progress the skull crusher: add a small increment, or lower behind the head for more stretch. To regress it: use an EZ-bar or dumbbells, and reduce the load.
Who It's For
Anyone building triceps with a barbell. Use an EZ-bar if the straight bar bothers your wrists, and never grind the last rep.
Equipment and Substitutions
What you need for this one: an EZ bar or dumbbells and a bench. If there is no bar free, the dumbbell and machine versions below are honest substitutes — the bar mainly buys you load, not a different stimulus.
Related Exercises
- Triceps Kickback — Triceps
- Dumbbell Skull Crusher — Triceps
- Seated French Press — Triceps
- Overhead Cable Triceps Extension — Triceps
- Band Triceps Pushdown — Triceps
- JM Press — Triceps
- Triceps Pushdown — Triceps
- Diamond Push-Up — Triceps, Chest
Common Questions
What muscles does the skull crusher work?
The skull crusher primarily trains the triceps.
How many sets and reps should I do?
Three sets of 8-12.
What are the most common skull crusher mistakes?
Most often: elbows flaring and drifting; going too heavy.
Do I need an EZ bar or dumbbells and a bench to do this?
This version uses an EZ bar or dumbbells and a bench, and it trains the triceps. Without a barbell, load the same pattern with dumbbells or a machine from the list below and accept a smaller top-end number.
Is this safe if I have an existing injury?
The skull crusher loads the knee, hip and lower back together, which means a problem in any one of them can surface here. If a rep reproduces the pain you already have, stop the set and get it looked at. Not medical advice.