Pec Deck Rear Delt Fly Guide: Form and Benefits

Master the pec deck rear delt fly with our expert guide to shoulder isolation, proper machine setup, and common mistakes for better posture.

How to Perform

  1. Adjust the seat height so the handles are aligned with your shoulder joints while seated.
  2. Face the machine and sit with your chest firmly against the vertical pad and your feet flat on the floor.
  3. Grasp the handles with a neutral or overhand grip, maintaining a slight bend in your elbows without locking them.
  4. Exhale as you pull the handles back in a wide arc until your arms are in line with your torso.
  5. Squeeze your shoulder blades together at the peak of the movement for one second.
  6. Inhale as you slowly return the handles to the starting position, maintaining tension on the muscles.
  7. Stop the weight stack just before it touches down to ensure constant resistance throughout the set.

Common Mistakes

  • Using momentum or swinging the torso to move the weight.
  • Shrugging the shoulders toward the ears during the fly.
  • Bending the elbows excessively and turning the move into a row.
  • Overextending the arms past the plane of the back.

Muscles Worked

Primary movers

  • Rear Deltoid

Stabilizers

  • Trapezius
  • Rhomboids
  • Infraspinatus

Related Guides

Rear Deltoid · Strength