JM Press (Smith Machine)

The Smith Machine JM Press is a hybrid compound exercise combining a close-grip bench press and a tricep extension to build mass and strength. By using the Smith machine, it provides a fixed path that allows for heavy loading while isolating the triceps brachii.

How Iridium Programs This

Iridium categorizes this as a high-stability movement that allows for significant loading without taxing stabilizer muscles, making it a viable option even when your 7-day history shows recent heavy pressing. To manage the intense mechanical stress placed on the elbow joint, Iridium strictly monitors your total triceps work against your Maximum Recoverable Volume.

Form Cues

Do
  • Set the bar path to align with your upper chest or neck area
  • Grip the bar slightly narrower than shoulder-width
  • Tuck your elbows in and drive them forward as you lower the weight
  • Lower the bar under control until your forearms contact your biceps
  • Drive the weight back up by extending your elbows forcefully
Don't
  • Don't let your elbows flare out to the sides
  • Don't lower the bar toward your stomach or lower chest
  • Don't bounce the bar off your body at the bottom
  • Don't allow your wrists to roll backward excessively

Common Mistakes

  • Flaring elbows outward
  • Using a grip that is too wide
  • Lowering the bar too low on the torso
  • Uncontrolled descent
  • Lifting too heavy too soon

Muscles Worked

This exercise is a powerhouse for the triceps, targeting all three heads with a specific emphasis on the lateral and medial heads due to the pressing mechanic. It also heavily recruits the forearms for stability and minimizes chest involvement, forcing the triceps to move the load.

Primary

Triceps Long HeadTriceps Medial Head

Secondary

Triceps Lateral HeadForearms

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