ArmsEZ bar or dumbbells + benchIntermediateTriceps (long head)
Skull Crusher
The skull crusher (lying tricep extension) is the primary tricep mass builder. It trains the long head — the largest portion of the tricep — through a stretched range of motion that pushdowns and dips can't reach.
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Form Guide
Step-by-step: Skull Crusher
1Lie on a flat bench. Hold an EZ bar or dumbbells over your chest, arms extended.
2Keep your upper arms vertical and stationary. Only the forearms move.
3Lower the bar to your forehead (or behind it for slightly more stretch).
4Do not let your elbows flare out wide — keep them roughly shoulder-width.
5Press back to full extension, contracting the tricep hard.
Common Mistakes
What most people get wrong
Elbows flaring: reduces tricep load and stresses the shoulder.
Upper arms moving: if your upper arms rock back and forth, you're benching with bent arms.
Bar dropping toward the neck vs the forehead: both acceptable but consistent form matters.
Programming
How to program the Skull Crusher
3 sets of 8–12 reps. Always include both an overhead extension (skull crusher or overhead extension) AND a pushdown variation for complete tricep development — each trains a different head dominantly.