JM Press

What the JM press actually trains

A JM press is a barbell exercise performed lying on a bench, in which you lower the bar towards your throat while the elbows travel forward and tuck under it, then press it back up.

It sits between a close grip bench press and a skull crusher, and it is not a compromise between them so much as a distinct movement. In a close grip bench the elbows stay relatively back and the chest and front delts share a great deal of the load. In a skull crusher the upper arms stay fixed and the elbows do all the work, but the load is limited by what your elbows will tolerate. The JM press lets the elbows travel forward as the bar descends, which shortens the effective lever and lets you use considerably more weight than a skull crusher while keeping the triceps as the main worker.

All three heads of the triceps brachii extend the elbow. Kholinne and colleagues found the heads contribute differently depending on arm position, and here the shoulder sits in a moderately flexed position at the bottom, so the long head is somewhat lengthened, more than in a pushdown and less than in a true overhead extension.

The chest and front delts still contribute, which is why this is classified as a compound rather than an isolation movement. That contribution is what allows the load, and the load is the whole reason to do it.

It is a powerlifting exercise by origin, used to build bench press lockout strength, and that remains its clearest use. For pure triceps size, an overhead extension is more targeted. For triceps size with heavy loading and a direct carryover to your bench, this is hard to beat.

Setting up and executing

Set a bench in a rack and lie back with your eyes roughly under the bar. Set the safety pins at a height that will catch a failed rep.

Take a grip just inside shoulder width. Narrower than that strains the wrists without buying you anything.

Unrack the bar and hold it over your shoulders with straight arms.

Lower the bar slowly towards your throat, letting the elbows travel forward and tuck under the bar as it descends. The forearms should stay close to vertical rather than angling back towards your head.

Stop a few centimetres from your neck and pause briefly with the elbows loaded.

Press the bar back up and slightly away, driving through the triceps, and finish with the arms straight over the shoulders.

The mistakes that cost you the most

Learning it heavy is the fault most likely to hurt you. The bar path is unfamiliar, the bottom position feels strange the first time, and the bar is travelling towards your throat. Spend a session with an empty bar until the movement is automatic before you load it.

Turning it into a close grip bench press is the most common drift. If the bar lands on your chest with the elbows back, you have swapped exercises and the chest is doing the work. The bar goes to the neck.

Turning it into a skull crusher is the opposite drift. If the elbows stay high and fixed while the bar travels past your head, you are doing a skull crusher with a suboptimal grip and you will not be able to use JM press loads.

Gripping too narrow is a habit imported from close grip benching. Anything much inside shoulder width forces the wrists into an awkward position at the tucked bottom, which Lehman's work on grip and forearm position suggests changes the demand without improving it.

And skipping the rack safeties is unnecessary risk on the one bench exercise where a failed rep travels towards your neck. Set the pins.

Sets, reps and rest by goal

This tolerates heavier loading than any other triceps focused movement.

For muscle gain, three sets of eight to twelve with two minutes rest. For strength, four sets of five to eight with three minutes. In a fat loss phase, three sets of ten to fifteen with ninety seconds.

Take the rest. This is a barbell press and it fatigues you systemically in a way that a pushdown does not.

Progress with small increments. Two and a half kilos total is a reasonable jump; the elbow position is unforgiving of load that arrives faster than your technique.

Schoenfeld and colleagues found a dose response between weekly hard sets and hypertrophy, and sets here count as both triceps and pressing volume, which is worth remembering when you total up your week.

Refalo and colleagues found stopping a rep or two short of failure produces comparable growth to going to failure. Apply that here more than usual. A failed JM press is a bar drifting towards your throat, and the last grinding rep is also the rep where the elbow position degrades.

If lockout strength on the bench is your goal, keep the reps at five to eight and treat it as a strength lift rather than a pump exercise.

Where it fits in your split

Early in a push or arm session, as the second pressing movement.

On push, pull and legs it belongs on push day after the main press. On a bro split it opens the triceps work on arm day. On an upper and lower split it serves as the triceps focused press in an upper session. On a full body programme it earns a slot when bench press lockout is your weak point.

Do it after your main press but before any isolation work. It is heavy enough to need a reasonably fresh nervous system and reasonably fresh elbows.

The complementary exercise is an overhead extension. Maeo and colleagues found substantially greater triceps growth from elbow extension trained with the arms overhead than with the arms at the sides, and while the JM press flexes the shoulder somewhat, it does not reach a true overhead position. A programme with a JM press and an overhead extension covers heavy loading and long head length between them.

Once or twice a week is enough. The elbows take real stress here and the movement is not one to accumulate endless volume on.

Variations worth knowing

The EZ bar JM press uses an angled bar, which lets the wrists sit more comfortably at the tucked bottom position and is the version most people should start with.

The close grip bench press keeps the elbows back and the bar on the chest, allowing much heavier loads with more chest involvement and less direct triceps work.

The skull crusher fixes the upper arms and lets the bar travel past the head, which lengthens the long head more but caps the load at what the elbows tolerate.

The dumbbell JM press uses independent hands, which lets the wrists rotate and suits shoulders that dislike a fixed bar.

The Smith machine version runs on a fixed path with safeties, which takes most of the nerves out of learning a movement that travels towards your neck.

And a board or pin press is the direct alternative if bench lockout is the only reason you are here, overloading the top of the range without the unfamiliar bar path.

What the evidence says

Kholinne and colleagues examined the distinct roles of the three heads of the triceps brachii during elbow extension and found their contributions vary with arm position, which is the basis for treating the moderately flexed shoulder position here as different from both a pushdown and an overhead extension.

Maeo and colleagues found triceps hypertrophy was substantially greater after training elbow extension in the overhead position than in the neutral arm position, which places the JM press somewhere in between and argues for pairing it with overhead work rather than relying on it alone.

Saeterbakken and colleagues compared bench press variations in trained athletes and found muscle activity and performance shift with the variation used, which supports treating the JM press as a genuinely distinct pressing movement rather than a close grip bench with a quirk.

Lehman examined grip width and forearm pronation and supination during the bench press and found grip position changes muscle contribution, supporting a grip just inside shoulder width rather than an extremely narrow one.

Pallarés and colleagues found full range training produced better strength and hypertrophy outcomes than partial range work, supporting a full descent to the neck rather than a shortened rep.

Schoenfeld and colleagues found a dose response between weekly hard sets and hypertrophy, and sets here count towards both triceps and pressing volume.

Refalo and colleagues found training close to failure is not necessary for growth, which is particularly welcome on a lift where failure means a bar above your throat.

Common questions

Is this dangerous?

It is a bar travelling towards your neck, so it deserves respect rather than fear. Set the rack safeties, learn the movement with an empty bar, and stop sets a rep or two short of failure. Done that way it is no riskier than any other barbell press.

How is it different from a close grip bench press?

In a close grip bench the elbows stay relatively back and the bar meets your chest, so the chest and front delts take a large share of the work. In a JM press the elbows travel forward and tuck under the bar as it descends towards your throat, which keeps the triceps as the primary worker. Both are useful; they are not interchangeable.

How is it different from a skull crusher?

A skull crusher fixes the upper arms so the elbows do all the work, which limits the load to what your elbows tolerate. The JM press lets the elbows travel, which shortens the lever and allows considerably more weight. The trade is that the chest and shoulders help a little.

Will it help my bench press?

That is what it was built for. Lockout on a bench press is a triceps problem for most lifters, and this loads elbow extension in a position close to the one you press from. Keep the reps at five to eight if that is your aim.

Should this be my only triceps exercise?

No. It loads heavily but the shoulder is only moderately flexed, so the long head is not trained at the length that produces the most growth. Pair it with an overhead extension and you have covered both heavy loading and long muscle length.