triceps intermediateAI Tracked

Skull Crusher

Skull crushers (lying tricep extensions) are one of the best exercises for building tricep mass. Unlike pushdowns which emphasize the lateral head, skull crushers hit the long head of the triceps — the biggest head, and the one that gives your arms the most size. The name sounds scary, but with proper form, it's a perfectly safe and incredibly effective arm builder.

How to Do Skull Crusher: Step by Step

  1. Lie on a flat bench holding an EZ bar or straight bar with a narrow grip
  2. Start with arms extended straight up, perpendicular to the floor
  3. Lower the bar toward your forehead by bending only at the elbows
  4. Keep your upper arms angled slightly back (toward your head, not straight up)
  5. Extend back to the starting position by straightening your elbows

Common Mistakes to Avoid

  • Elbows flaring out wide — keep them shoulder-width throughout
  • Upper arms moving — only your forearms should move, upper arms stay fixed
  • Lowering the bar to your nose/chin — aim for the forehead or just above for full range

Muscles Worked

triceps
Equipment barbell, bench
Tracking Count reps

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