Smith machine JM press
Exercise details
- Target muscle: Triceps Brachii
- Synergists: Sternal (Lower) Pectoralis Major, Clavicular (Upper) Pectoralis Major, Anterior Deltoid
- Dynamic stabilizer: Biceps Brachii (short head only)
- Mechanics: Compound
- Force: Push
Starting position
- Place a flat bench under the bar of the Smith machine so that after you lie down the bar will be able to descend to your upper chest/throat/chin region.
- To prevent the bar from being able to injure your person by dropping too low, secure the safety pins of the Smith machine.
- Lie on your back (supine) on the bench and grasp the bar using a pronated (overhand) shoulder-width grip.
- Spread your legs and plant your feet flat on the floor for stability.
- Unlatch the bar from the rail by rotating it.
Execution
- Keeping your elbows high and approximately 45 degrees out to your sides, inhale as you carefully lower the bar towards your upper chest/throat/chin, stopping when your forearms make contact with your biceps.
- Exhale as you press the bar back up to the starting position.
- Repeat for the prescribed number of repetitions.
- After you have finished, rotate the bar to latch it back on to the rail.
Comments and tips
- Keeping your elbows high will emphasize elbow extension over horizontal shoulder flexion, thus ensuring greater involvement of your triceps brachii than your pectoralis major and anterior deltoid.
- The Smith machine JM press requires practice. Start light and increase the amount of weight that you use gradually as you master proper form.
- Don’t forget to use the safety pins.
- This exercise is also known as the Smith machine Blakly press.
- See also the barbell JM press.
Smith machine JM press videos
Here’s JM Blakly, the inventor of the JM press, explaining the history and proper form of the exercise.
