Shoulders
Traps, Middle Back
Attach dual handles to a sled connected by a rope or chain and load the sled with a light weight.
Stand facing the sled and back up until there is tension in the line. Hold the handles at arm's length at about waist level.
Bend your knees slightly, keep your chest and head up, and maintain a straight back. This is your starting position.
Without bending your elbows, pull the handles upward and apart, performing a reverse fly with some external rotation. Ensure your palms face forward during the movement.
Return to the starting position by controlling the movement, and take a couple of steps back to maintain tension in the line.