Skull Crusher
Muscles worked
Instructions
- 1Using a close grip, lift the EZ bar and hold it with your elbows in as you lie on the bench. Your arms should be perpendicular to the floor. This will be your starting position.
- 2Keeping the upper arms stationary, lower the bar by allowing the elbows to flex. Inhale as you perform this portion of the movement. Pause once the bar is directly above the forehead.
- 3Lift the bar back to the starting position by extending the elbow and exhaling.
- 4Repeat.
table_chartRecommended sets and reps
These ranges vary depending on your training goal — adjust the load accordingly.
| Goal | Sets | Reps | Rest |
|---|---|---|---|
| Strength | 3–4 | 6–8 | 2–3 min |
| Hypertrophy | 3–4 | 10–15 | 60 s |
| Endurance | 2–3 | 15–20 | 30–45 s |
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About Skull Crusher
The skull crusher, or lying triceps extension, is performed on a bench, the bar (ideally an EZ bar) lowered toward the forehead or slightly behind the head. Elbows fixed and pointing at the ceiling, you move only the forearms, which intensely targets all three heads of the triceps. Lowering the bar behind the head increases the long-head stretch. It is one of the best mass builders for the back of the arm, but also one of the toughest on the elbows: warm them up, pick a reasonable load and keep a slow, controlled descent.
check_circleBenefits
- check_circleHeavily loads all three heads of the triceps
- check_circleAllows heavier loading than single-arm extensions
- check_circleLowering behind the head increases the long-head stretch
- check_circleAn isolation movement that still allows relatively heavy loading
- check_circleAdapts to a straight bar, EZ bar, or dumbbells depending on comfort
lightbulbExecution tips
- lightbulbKeep the elbows fixed and pointing toward the ceiling
- lightbulbLower the bar to the forehead or behind the head, without flaring
- lightbulbUse an EZ bar if your wrists are sensitive
- lightbulbControl the descent and never bounce at the bottom
- lightbulbHave a spotter or safety pins ready if you're loading up heavy on this movement
warningCommon mistakes
- warningLetting the elbows flare out to the sides
- warningMoving the shoulders and turning it into a pull-over
- warningLowering too fast and risking hitting your forehead
- warningBending the wrists backward under the load
- warningChoosing too short a range of motion out of fear of hitting the forehead
tuneVariations and alternatives
- tuneLying dumbbell triceps extension — more natural path, unilateral work possible
- tuneJM press — a skull crusher/close-grip bench hybrid, heavier loading
- tuneRope overhead triceps extension — a standing variation, less risk
- tuneIncline bench triceps extension — a different resistance angle
person_checkWho it's for and level
The skull crusher suits intermediate to advanced lifters looking for one of the best triceps mass builders. Its relatively heavy loading and proximity to the face make it less suited as a very first triceps exercise for a complete beginner, who will benefit from mastering the cable extension first.
shieldSafety and precautions
Keep the elbows fixed and pointing toward the ceiling throughout the movement, and choose a reasonable load you fully control, since the bar passes close to your face. Get a spot on heavy loads and warm up the elbows well before starting.
calendar_monthWhere to place it in your program
Place the skull crusher at the start or middle of a triceps session, after a light warm-up, for 3 to 4 sets of 8 to 12 reps. A controlled load and descent matter more than the weight lifted.
helpFrequently asked questions
Should I lower the bar to the forehead or behind the head?
Lowering behind the head keeps constant tension and stretches the long head more; to the forehead the contraction is shorter but still effective.
Do skull crushers hurt the elbows?
With an EZ bar, controlled loads and stable elbows, discomfort is rare; avoid bouncing and overloading the movement.
EZ bar or straight bar for skull crushers?
The EZ bar is preferable: its semi-neutral grip reduces twisting stress on the wrists and elbows. The straight bar is possible but harder to tolerate over time.
Can dumbbells be used instead of a bar?
Yes, the dumbbell version allows a more natural path and unilateral work if needed.
How many reps should I aim for?
Between 8 and 12 reps per set for a good balance between strength and volume.
Do I need a spotter for this exercise?
Recommended on heavy loads, since the bar passing close to the face makes a spot reassuring.
Is this suitable for beginners?
With a very light load and well-mastered technique, yes, but it's better to first learn the cable extension.
What's the difference between the skull crusher and the JM press?
The JM press is a hybrid between the skull crusher and close-grip bench press, allowing even heavier loading.
Should I warm up the elbow before this exercise?
Yes, a light empty-bar set or one with minimal load prepares the joint well before loading up.
Can this be done on the floor without a bench?
Yes, but range of motion is reduced since the floor limits how far the bar can travel behind the head.
Can this exercise be done with a standard Olympic bar?
Yes, a standard Olympic bar works just as well as an EZ bar, provided you accept a more demanding grip on the wrists.
How many sets are recommended per session?
3 to 4 sets are enough, alongside a heavy compound movement like the close-grip bench press.
Does this pair well in a superset with a biceps curl?
Yes, it's a classic and effective combination for pairing triceps and biceps at the end of an arm session.
Is it normal for the elbows to click slightly during this exercise?
A mild click without pain is usually harmless, but any sharp pain or persistent clicking should prompt reducing the load or consulting a professional.
Can bands replace plates for progressive resistance?
Yes, adding floor-anchored bands changes the resistance curve, making it heavier near the top of the movement.
Can this be done with a partial range of motion if the elbow feels uncomfortable?
Yes temporarily, reducing the descent to about two-thirds of the full range until the joint feels better.
Should the elbow be fully locked out at the top?
Yes, without forcing it, to properly contract the triceps before lowering under control again.
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