Dynamic stabilizer: Biceps Brachii (short head only)
Mechanics: Compound
Force: Push
Starting position
Lie supine (on your back) on a flat bench, spread your legs, and plant your feet flat on the floor for stability.
Dismount the barbell using a shoulder-width grip.
Execution
Keeping your elbows high, inhale as you lower the barbell in a straight line towards your upper chest/throat/chin, stopping when your forearms make contact with your biceps. (To maintain a secure grip on the barbell, you will have to flex your wrists a little as the barbell descends.)
Exhale as you press the barbell back up to the starting position.
Repeat for the prescribed number of repetitions.
Comments and tips
Keep your elbows high and approximately 45 degrees out to your sides. Keeping your elbows high will emphasize elbow extension over horizontal shoulder flexion and therefore emphasize the involvement of your triceps brachii while minimizing the involvement of your pectoralis major and anterior deltoid.
This exercise requires practice. Start light and increase weight as you master proper form.
After you master form, start to push the barbell upward more rapidly to develop greater triceps power.
The barbell JM press is a cross between a barbell skull crusher and a barbell bench press. It was invented by powerlifter JohnMark ‘JM’ Blakly. The name of the exercise wasn’t actually coined by Blakly but Louie Simmons and George Halbert of Westside Barbell, who named the exercise after Blakly when he first started training there. A bench press specialist, Blakly competed in powerlifting in the early ‘90s. He holds six world records, is a four-time world bench press champion, and was the eleventh man in history to bench press 700 pounds. The barbell JM press was one of the only triceps exercises Blakly would use, and he credits it for building all of his triceps strength for bench pressing. See the video for Blakly’s barbell JM press demonstration.
