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JM Press
Arms

JM Press

TricepsBarbell
beginner · compound · strength

Also works: Chest · Shoulders

Half skull crusher, half close-grip bench: the bar drops towards the throat like an extension, then the upper arms rotate forward mid-rep so you finish with a press. Named after powerlifter JM Blakley, it loads the triceps at the exact joint angle where most benches stall.

How to

Own the movement

Set up first, then execute. Every cue below is something you can check on your next set.

Before the first rep

  • Lie on a flat bench and take a grip roughly shoulder-width, not narrower. A hand-touching grip wrecks the wrists here.
  • Unrack and set the bar directly above your upper chest, not above your shoulders — the whole lift lives in that plane.
  • Tuck your elbows so the upper arms sit close to your ribs before the first rep.
  • Plant your feet and keep a light arch; the bench setup is the same as any press even though the path is not.
  • Start light enough that you can practise the roll-back empty — this is a coordination lift before it is a strength lift.

Every rep

01
Lower the bar towards your throat by bending only the elbows, exactly as you would start a skull crusher.
02
At about halfway down, let the upper arms drift forward towards your feet until they are roughly perpendicular to your torso, keeping the elbow angle unchanged.
03
The bar should end up close to your chin or upper chest with the forearms near vertical — it feels like the bar is rolling back an inch, not dropping.
04
Press straight up out of that position using the triceps, driving the elbows to a full lock.
05
Keep the whole rep smooth and continuous. If the descent and the roll-back happen as two separate events, slow down and lighten the bar.

Breathing & tempo — Inhale and hold through the descent and the roll-back, exhale as you drive to lockout. Two to three seconds down, immediate and fast on the press.

Before you load it

  • Bench in a rack with the safety pins set just above your chest. A failed JM press ends with the bar over your throat, not your chest.
  • Stop the set at the first rep where your elbows feel sharp rather than worked. This position stresses the elbow tendons harder than most triceps work.
Programming

Sets, reps & load

Where to start, and what to change when it stops being hard.

Strength
4-5 sets of 5-6
Hypertrophy
3-4 sets of 8-12
Endurance
2-3 sets of 15

Learn the path with the empty 20 kg bar for a full session before loading it. Then start at roughly 40-50% of your close-grip bench for sets of 8. A good working marker is around 60% of your close-grip bench for a strict set of 6. Add 2.5 kg only when the mid-rep transition stays continuous — jerky reps mean the weight has outrun the skill.

Fix your form

What goes wrong

The errors that show up most often, and the cue that fixes each one.

Turning it into an ordinary close-grip bench press by never bending the elbows first.

Start every rep by moving only the forearms, bar towards the throat. The upper arm should not travel at all for the first half of the descent.

Gripping the bar with the hands touching to make it feel more like a triceps lift.

Use a grip about shoulder-width, index fingers roughly on the smooth ring. The narrowness comes from tucking the elbows, not from the hands.

Loading it like a close-grip bench because the top half feels similar.

Start around 40-50% of your close-grip bench and only add weight once the roll-back stays smooth for every rep of every set.

Letting the bar drift back over the shoulders at lockout.

Finish each rep with the bar over the upper chest, not the face or the collarbone. Have someone watch the bar path from the side for one set.

Running it heavy in the same week as heavy skull crushers.

Pick one elbow-flexed triceps lift per week and let the other be a pushdown or a bodyweight press. Elbow tendons recover slower than the muscle does.

The case for it

Why bother

A skull crusher loads the triceps with the shoulder fixed; a close-grip bench loads them with the shoulder moving. The JM press splits the difference inside one rep — the elbow flexes to roughly 90 degrees under a load close to bench weight, and the mid-rep roll-back keeps the forearm from ever getting the mechanical relief that a pure extension offers at the bottom.

That matters because the sticking point on a heavy bench sits a few centimetres off the chest, where the triceps take over from the pecs. This trains that handoff with a bar you can actually load, which is why it survives in powerlifting gyms while prettier triceps work does not.

Where it fits

Second movement on a bench day, straight after your main press, 3-4 sets of 6-10. One session a week is plenty. Do not pair it with heavy skull crushers in the same week — both hammer the same elbow tissue and the elbows, not the triceps, decide how much of this you can absorb.

Questions

Asked and answered

How is this different from a skull crusher?

A skull crusher keeps the upper arm still for the whole rep and lets the bar travel behind your head. The JM press deliberately moves the upper arm forward halfway down, so the bar finishes near your chin over your chest and you press it up rather than extending it back. The result is more load, less shoulder stretch, and a stronger overlap with your bench sticking point.

Why does it feel awkward the first few sessions?

Because it is one motion made of two, and your nervous system wants to pick one. Spend a whole session with the empty bar doing sets of 10, watching from the side in a mirror. The transition becomes automatic in two or three sessions and the lift stops feeling strange.

Will it hurt my elbows?

It can if you run it heavy year-round. The position holds the triceps loaded through a deep elbow bend, which is exactly the stress that irritates the tendon at the back of the elbow. Keep it to one session a week, keep reps at 6 or above, and stop the moment the sensation goes sharp rather than fatiguing.

Should I do this or close-grip bench for a bigger bench?

Close-grip bench first if you only do one, because it carries more total load and is closer to the competition lift. Add the JM press when your bench dies a few centimetres off the chest rather than at the top — that specific failure is the one it addresses.

Enough theory.
Go log a set.