Intermediate

Smith Machine Skull Crusher

The guided bar keeps the load on a straight track, so you can grind hard triceps sets and rack the bar instantly if you stall. That security lets you load skull crushers heavier than usual while all three heads share the work. It suits lifters who want to overload the extension pattern without a spotter.

Body part
Triceps
Type
Strength
Browse by movement
Elbow Extension
Muscles worked
Target
Triceps Brachii Long Head, Triceps Brachii Lateral Head, Triceps Brachii Medial Head

How to do it

  1. 1

    Position a flat bench inside the Smith machine so the bar lines up above your forehead.

  2. 2

    Lie back and take a shoulder-width overhand grip on the bar.

  3. 3

    Unhook the bar and press it to lockout with the upper arms angled slightly back.

  4. 4

    Bend the elbows to lower the bar along its track toward the top of your head.

  5. 5

    Extend the elbows to press back to lockout, then squeeze the triceps.

  6. 6

    Inhale as you lower and exhale as you press; twist the bar to rack it when done.

Tips

  • Set the bench position first so the fixed path drops just above your forehead, not onto your face.
  • Keep the elbows tracking forward rather than flaring out against the guided bar.
  • Because you can go heavy here, keep the reps controlled and the lockout honest.

Variations

Common mistakes

  • Leaving the safety stops at the bottom of the track when they could sit a hand's width above your head. Set them and a failed rep parks itself instead of landing on you.
  • Fighting the machine by trying to arc the bar back over your head. The track only travels up and down, so move the bench until that straight line falls where you want it, then hinge at the elbow only.
  • Spreading the hands wide because the fixed bar feels stable there. A wide grip pushes the elbows out and turns the bottom into a shoulder stretch rather than a triceps stretch, so keep the hands at shoulder width.
  • Adding plates because the machine feels safe and then halting the bar well short of your head. The extra load buys nothing if it costs you the bottom of the range.

Frequently asked

How should I program the Smith machine skull crusher?
This is the skull-crusher variation you can safely take heavier, so a top set of 6 to 8 followed by two back-off sets of 12 to 15 uses it well. Set the stops first, then push the top set close to failure. Rest two minutes after the heavy set and about a minute between the lighter ones. If your elbows are new to loaded extensions, leave the top set out for the first few weeks and run three sets of 10 to 12.
What can I do instead of a Smith machine skull crusher?
An EZ-bar skull crusher with a spotter is the direct equivalent, and dumbbells let you bail by setting the weights down beside you. If it is the safety you want without a partner, a lying cable extension with a rope from a low pulley cannot fall on you, since you let go at the end of the set and the stack drops. In a rack, an EZ bar with the safety pins set above your head gives you the same insurance the Smith stops do.
Why use a Smith machine for skull crushers?
Because the bar cannot go anywhere but up and down, you can load the extension pattern hard, train alone, and rack the bar the instant a rep stalls, which suits lifters chasing triceps size without a spotter. The trade is that fixed path: your arms have to accept the machine's line rather than the arc they would choose, and if that line irritates your elbows or shoulders, take the hint and use an EZ bar or dumbbells. It is also a poor first skull crusher, since the free-weight version teaches the path.

Related exercises

Other movements among FitRay's 2,000+ exercises that load the same target muscle — same equipment and level first.

All Triceps exercises