WhatWorksWhat.
Triceps

Skull Crusher

Deep stretch on the back of the upper arm at the bottom; locks out hard.

Complexity · Lowhypertrophyintermediate+EZ barBench
  • Triceps
  • Triceps - Long-head triceps
  • Triceps - Outer triceps
  • Long-head triceps
  • Outer triceps
  • Inner triceps

PrimarySecondary

What it hits

Parts of the target muscle.

  • Long-head triceps

    Hit

    Crosses the shoulder - hit best with arms overhead.

  • Outer triceps

    Hit

    Lateral head - hit hardest with pronated pushdown.

  • Inner triceps

    Not hit

    Medial head workhorse - always involved, peaks at lockout.

The movement

Get it right, not roughly right.

Optimal form

0:16· FIT.nl

How to Do Lying Triceps Extension (Skull Crusher) | Proper Form Tutorial

Bottom (stretch)

Lockout

Lying on a bench, EZ-bar held over the chest with arms angled slightly back toward the head - not straight up. Lower the bar past the forehead by bending only at the elbow. Drive back up.

Common mistakes

  • Bar straight up over the face - kills the long-head stretch.
  • Flaring elbows out wide - elbow joint takes the hit.
  • Lowering to the chin and bouncing - top reason for elbow tendinitis.

Where you should feel it

Deep stretch on the back of the upper arm at the bottom; locks out hard.

Injury risk · 4/10

Progression

Step back, or step up.

Same movement family, different rung. Harder versions sit above, easier versions below — tap a rung to land there.

  1. You're hereSkull Crusher
  2. Step back toTriceps pushdownSame elbow extension, no overhead loading on the joint.
  3. Step back toOverhead triceps extensionSame long-head stretch with the elbow in a friendlier position.

Variations

Same movement, moved emphasis.

Ranked by how directly each variation still trains triceps. 80%+ means the target barely changes. Below 60%, the emphasis has meaningfully shifted — useful for variety, but less precise for the specific part. The label calls it at a glance.

  • Cable skull crusher

    Lying with the cable behind you.

    100% on target

    On target

    Constant tension.

  • Decline skull crusher

    Bench at slight decline, arms angle further back.

    100% on target

    On target

    Larger long-head stretch.

  • Dumbbell skull crusher

    Two dumbbells, neutral grip.

    95% on target

    On target

    Same target, minor adjustment.

Compare with another exercise

Cool-down

Worked it. Walk it back down.

A couple of minutes here pays back in soreness avoided tomorrow. Browse the full library.

  • Overhead Triceps Stretch

    Reach one arm overhead and bend the elbow so the hand drops behind the head. Use the other hand to gently press the elbow back. 30s per side.

    TricepsLats

  • Behind-the-back Triceps Stretch

    One arm reaches behind the back from above, the other behind from below. Try to clasp the hands - or use a towel between if you can't. 30s per side.

    Triceps