What is the difference between a JM press and a skull crusher?

In a skull crusher the upper arms stay fixed and only the elbows bend, lowering the bar toward the forehead. In the JM press the elbows also drift forward and the bar comes down toward the chin, so the movement sits between a skull crusher and a close-grip bench press.

How heavy should I go on the JM press?

Start well below your close-grip bench press weight and stop each set with a couple of reps left while you learn the bar path. Moderate sets of 6 to 12 reps suit most lifters, and heavier sets are best saved until the elbows are used to the lift.

Can I do the JM press with an EZ bar or in a Smith machine?

Yes. An EZ bar angles the hands slightly, which many lifters find easier on the wrists, and a Smith machine keeps the bar on a fixed track with built-in safety stops, though the path is straighter than with a free barbell.

Where does the JM press fit in a workout?

It works best after your main bench press or pressing work, as a triceps accessory while you are still fresh enough to control the bar. Many lifters use it in place of a skull crusher or close-grip bench press on a given day rather than doing all three.

Is the JM press good for beginners?

Not as a first triceps exercise. It is a technical lift that loads the elbows heavily, so beginners do better building a base with the Barbell Bench Press (Close Grip) and the Cable Triceps Pushdown (Straight Bar) first.

Barbell JM Press

What Is the Barbell JM Press?

Barbell JM Press is a compound exercise that primarily targets the triceps and also engages the chest and the front of the shoulders. It is an advanced-level movement that blends a close-grip bench press with a skull crusher. The bar starts over the shoulders like a press, then travels down and back toward the chin as the elbows bend and drift forward, so the elbows do far more of the work than the shoulders.

The lift is named after powerlifter JM Blakley, who developed it to keep training his triceps hard when his chest and shoulders were worn down from bench pressing. Powerlifters and competitive bench pressers still use it for that reason, as an accessory for the lockout, the top part of a press where the elbows straighten. It usually comes after the main bench press or pressing work in a session, in place of or alongside other triceps exercises.

Compared with a close-grip bench press, the JM press keeps the bar higher on the body and lets the elbows bend much further, which shifts the load away from the chest and onto the triceps. Compared with a skull crusher, the upper arms are allowed to move and the bar stays closer to the body, so the movement feels more like a press. Most lifters handle noticeably less weight than on their close-grip bench press. An EZ bar version eases the wrists, and the Dumbbell Tate Press is a dumbbell triceps press with a similar goal.

The JM press suits lifters who already bench press with solid technique and want stronger lockouts or bigger triceps. It is a technical lift that places a lot of stress on the elbows, so it is worth building a base first with the close-grip bench press, cable triceps pushdowns and a light lying triceps extension. Learn it with light weight and add load slowly, because tendons adapt to heavier training more slowly than muscle does.

Muscles Worked

MuscleActivation

Triceps Brachii (Lateral Head): Primary
Triceps Brachii (Medial Head): Primary
Triceps Brachii (Long Head): High
Deltoid: Medium
Pectoralis Major: Medium
Flexor Carpi Radialis: Low
Flexor Carpi Ulnaris: Low
Serratus Anterior: Low

Instructions

Lie on a flat bench with your eyes under the bar, feet flat on the floor and shoulder blades pulled back into the bench.
Grip the bar overhand with your hands a little narrower than shoulder width, about 15 to 18 inches apart.
Unrack the bar and hold it at arm's length over your shoulders, arms straight and wrists stacked over your forearms.
Bend your elbows and let them travel forward toward your feet, keeping your upper arms angled about 45 degrees out from your torso.
Lower the bar down and back toward your chin under control, keeping your wrists straight.
Stop when your forearms press firmly into your biceps, with the bar just above your chin.
Press the bar back up along the same path until your elbows are straight and the bar is over your shoulders again.
Keep your back on the bench and your feet planted for every rep, then rerack the bar after the last rep.

Common Mistakes

Turning it into a skull crusher
Locking the upper arms in place and lowering the bar to the forehead loses the JM press pattern and puts skull crusher stress on the elbows.
Turning it into a bench press
Letting the elbows drop beside the torso and the bar sink toward the chest shifts the work to the chest and shoulders.
Flaring the elbows wide
Elbows that point out to the sides turn the lift into a wide press and take tension off the triceps.
Gripping too narrow
Hands much closer than about 15 inches make the bar hard to balance and add strain to the wrists.
Adding weight too fast
Jumping in load before the elbow tendons have adapted invites elbow pain on this lift.
Letting the wrists fold back
Wrists that bend back under the bar strain the wrist joint and make the bar path harder to control.

Injuries

Barbell JM Press is a medium risk exercise when performed with proper technique. Most of the strain falls on the elbows, where the triceps tendon works hard as the elbows bend deeply under load, and on the wrists, which hold the bar over bent elbows. The bar also travels toward the chin and throat, so a missed rep comes down near the face and neck.

Start well below your close-grip bench press weight and add load in small steps, since the elbow tendons adapt more slowly than the triceps get stronger. Do one or two light warm-up sets before your working sets. Train inside a power rack with the safety arms set just below the lowest point of the bar path, or with a spotter, and keep the elbows pointing toward your feet rather than flaring out to the sides or dropping beside the torso.

If the elbows or wrists complain, switch to the Barbell Bench Press (Close Grip), the Smith Machine Bench Press (Close Grip) or the Cable Triceps Pushdown (Straight Bar) until they settle. Once the movement feels smooth, progress by adding weight gradually or by pausing briefly at the bottom of each rep.

Stop the set if you feel sharp pain at the back, inside or outside of the elbow, pain in the wrist, or pinching at the front of the shoulder. Elbow soreness that lingers into the next day is a sign to cut the load or take a break from the lift.

Overview

Primary Focus: Triceps
Equipment: Barbell and bench
Modality: Strength
Difficulty: Advanced

Alternative Exercises

Frequently Asked Questions

Q: What is the difference between a JM press and a skull crusher?: In a skull crusher the upper arms stay fixed and only the elbows bend, lowering the bar toward the forehead. In the JM press the elbows also drift forward and the bar comes down toward the chin, so the movement sits between a skull crusher and a close-grip bench press.
Q: How heavy should I go on the JM press?: Start well below your close-grip bench press weight and stop each set with a couple of reps left while you learn the bar path. Moderate sets of 6 to 12 reps suit most lifters, and heavier sets are best saved until the elbows are used to the lift.
Q: Can I do the JM press with an EZ bar or in a Smith machine?: Yes. An EZ bar angles the hands slightly, which many lifters find easier on the wrists, and a Smith machine keeps the bar on a fixed track with built-in safety stops, though the path is straighter than with a free barbell.
Q: Where does the JM press fit in a workout?: It works best after your main bench press or pressing work, as a triceps accessory while you are still fresh enough to control the bar. Many lifters use it in place of a skull crusher or close-grip bench press on a given day rather than doing all three.
Q: Is the JM press good for beginners?: Not as a first triceps exercise. It is a technical lift that loads the elbows heavily, so beginners do better building a base with the Barbell Bench Press (Close Grip) and the Cable Triceps Pushdown (Straight Bar) first.