Skull crushers

The skull crusher is an elbow extension done lying down, with the upper arms held still and the weight lowered towards the head. It is the triceps exercise that loads the long head hardest, because the shoulder stays flexed while the elbow works.

How far back you take the bar decides how much of that long head you get. Lowering to the forehead is the short version. Lowering past the head, to the bench behind you, is where the stretch is.

Sets, reps and RIR

Single-joint work responds to reps and time under tension more than to heavy load.

RIR means reps in reserve: how many you could still have done when you racked it. RIR 2 is two short of failure.

How to do it

1. Lie on a flat bench with an EZ bar, hands about shoulder width on the angled part of the bar.
2. Press the bar up and then tip the upper arms slightly back, so they point towards the ceiling and a little over your head.
3. Bend at the elbow and lower the bar in an arc past your forehead, towards the bench behind you.
4. Keep the upper arms where they are. Only the forearm moves.
5. Stop when you feel the triceps stretched, then extend back to the start without locking out hard.

Common mistakes

Upper arms drifting back on every rep

That turns it into a pullover and gives the triceps a rest at the top. If they move, the weight is too heavy or the set is over.

Flaring the elbows out

Wide elbows shorten the range and put the strain on the joint rather than the muscle. Keep them roughly shoulder width, pointing forward.

Bouncing out of the bottom

The stretched position is the reason to do the exercise. Reaching it fast and leaving it fast skips the part that works.

Going too heavy on a straight bar

If your elbows hurt, the bar is usually the cause before the exercise is. An EZ bar or dumbbells let the forearm rotate into a position that does not pinch.

How it differs from the neighbouring variants

The overhead triceps extension takes the same long head further into the stretch, standing or seated, and most people handle less weight on it. The triceps pushdown works the same muscle with the shoulder down, which favours the lateral head and is much easier on the elbow.

The close-grip bench press and the JM press are the pressing versions: more total load, more triceps work per session, but the chest and front delt help, so the triceps stop being the limit.

What it suits

Skull crushers go after pressing, when the triceps are already warm. Eight to fifteen reps, one or two in reserve. If your elbows are sore, move to pushdowns for a few weeks rather than dropping triceps work altogether, and come back to this with dumbbells.

Muscles worked

Primary: Triceps.

Estimate your one-rep max

Epley's formula, from a set you have actually done. It is an estimate, and it drifts above eight reps, so keep the input between one and twelve.

What it is called elsewhere

• Norsk Skull crushers
• Svenska Skull crushers
• Dansk Skull crushers
• Deutsch Stirndrücken
• Español Press francés tumbado
• Italiano Skull crusher
• Português Tríceps testa (barra)
• Русский Французский жим лёжа
• Français Barre au front

Related arms exercises

• Biceps curl
• Hammer curl
• Concentration curl
• Incline dumbbell curl
• Overhead triceps extension
• Triceps kickbacks

athlate logs this exercise, keeps the numbers, and tells you what you lifted last time.