Skull Crusher
Also known as: lying triceps extension, skullcrusher, french press exercise
Lying back with a bar lowered toward your forehead, the skull crusher is the heaviest pure elbow-extension exercise most lifters will do. Because the upper arms sit vertical or angled back overhead, the long head of the triceps works from a stretched position while all three heads move real load. It has built big arms for decades — the only price is respecting the elbows with smart bar choice and tempo.
How to do the skull crusher, step by step
- Lie on a flat bench holding an EZ-bar or barbell over your chest with a shoulder-width or slightly narrower grip.
- Angle your upper arms back toward your head about 10–20 degrees past vertical and hold them there.
- Bend only at the elbows, lowering the bar toward your forehead or just behind your head.
- Descend for two to three seconds until you feel a full stretch in the triceps.
- Reverse by extending the elbows, driving the bar back up along the same path.
- Finish each rep with straight arms, upper arms still angled back, and keep the shoulders quiet throughout.
Form cues that fix most reps
Lowering the bar behind your head rather than to your forehead keeps tension on the long head and pressure off the elbows.
An EZ-bar or dumbbells beat a straight bar here for most people's wrists and elbows.
Keep the upper arms frozen at their backward angle — if they pump back and forth, you're pressing, not extending.
Common mistakes (and the fix)
Skull Crusher sets and reps
Match the rep range to your goal, not the other way around. These are the standard evidence-based ranges:
| Goal | Sets × Reps | Rest |
|---|---|---|
| Strength | 3–5 × 3–6 | 2–3 min |
| Muscle growth | 3–4 × 8–12 | 60–90 sec |
| Endurance | 2–3 × 15–20 | 30–60 sec |
How our free programs prescribe it
Push · volume3 × 10–12Power + Hypertrophy U/L
Upper · power2 × 6–10Body-Part 5-day
Arms3 × 10–12
Skull Crusher FAQ
What muscles does the skull crusher work?
All three heads of the triceps, with the long head emphasized because the upper arms are held vertical or slightly overhead, stretching it across the shoulder. Nothing else contributes meaningfully when the upper arms stay still.
Are skull crushers bad for my elbows?
They have that reputation mostly from being done heavy, fast, and bounced. Use an EZ-bar or dumbbells, lower on a two-to-three-second count, keep a rep or two in reserve, and most lifters train them pain-free. If they still ache, overhead cable extensions load the same head with a smoother resistance curve.
How many sets and reps should I do?
Three sets of 8–12 reps, done after your pressing but before high-rep pump work. Progressing by half-steps of weight or an extra rep per week protects the elbows while still moving the lift forward.
More triceps exercises
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