Exercises

Pec deck / Butterfly

Bring the padded machine arms together in front of your chest with your back supported.

Front view of the open pec deck position with upper arms to the sides and upright forearms against the pads.

Machine · Forearm pads

Source: ACE · Pec Deck: Exercise Technique (PDF)

Step by step

  1. Adjust the seat so your upper arms are around shoulder height; plant both feet.
  2. Keep your back against the pad and forearms on the rests, elbows bent about 90 degrees.
  3. Bring the pads together slowly in front of your chest.
  4. Reopen with control, without pulling your arms far behind your torso.

Common mistakes

  • Lifting your upper back to finish the movement.
  • Letting the machine pull your shoulders far backward.

Anatomy and technique: the references below. Region boundaries and movement diagrams are schematic. Exercise images are AI-generated illustrations.