The bent-over reverse fly is an effective resistance exercise targeting the upper body muscles responsible for pulling movements. It involves hinging the torso forward and raising weights out to the sides through horizontal abduction. The primary goal is to strengthen the muscles on the back of the shoulder girdle and the upper back. Understanding the specific muscle groups engaged helps ensure proper form and maximizes the training effect.
Proper Execution of the Bent Over Reverse Fly
The movement begins from a standing position, holding a weight in each hand with a neutral grip, and involves bending the knees slightly. The torso then hinges forward at the hips, maintaining a flat back and a neutral spine, until the chest is positioned nearly parallel to the floor or at least at a 45-degree angle. This bent-over posture is fundamental, as it aligns the line of resistance to effectively target the posterior shoulder and upper back musculature.
The arms hang down below the shoulders with a slight, fixed bend at the elbow joint throughout the entire repetition. To initiate the lift, the dumbbells are raised out to the sides in a wide arc, moving away from the midline of the body. The movement is controlled, focusing on drawing the shoulder blades toward the spine as the weights reach shoulder height. The return phase is equally deliberate, slowly lowering the weights to the starting position without losing tension in the muscles.
The Primary Movers: Targeting the Upper Back and Shoulders
The primary muscle performing the lift is the posterior deltoid, located on the back of the shoulder. This muscle is responsible for horizontal abduction, moving the arm away from the torso in the horizontal plane. The hinged torso position optimally isolates and heavily recruits the posterior deltoid.
Working in concert with the posterior deltoids are the rhomboids (major and minor), situated beneath the trapezius. The rhomboids are the main drivers of scapular retraction, pulling the shoulder blades inward toward the spine. The middle and lower fibers of the trapezius muscle also contribute significantly to this retraction and upward rotation of the shoulder blade.
Secondary and Supporting Muscle Groups
Beyond the primary movers, several other muscles play a supportive role, stabilizing the body and the shoulder joint throughout the movement. The rotator cuff muscles, particularly the infraspinatus and teres minor, stabilize the head of the humerus within the shoulder socket. This maintains joint integrity as the arm performs the horizontal abduction motion.
The erector spinae, a group of muscles running along the spinal column, engages in a sustained isometric contraction to maintain the bent-over posture. This group works hard to prevent the torso from collapsing forward under the pull of gravity and the added weight. Deep core muscles, including the transverse abdominis, also brace the trunk, providing a stable foundation for the arms to move.
Modifying Form for Specific Muscle Emphasis
Minor adjustments to the execution can subtly shift the muscular focus. To emphasize the posterior deltoids and reduce reliance on the upper back, focus on moving the arms purely through the shoulder joint. This minimizes the conscious effort to squeeze the shoulder blades together, lessening the recruitment of the rhomboids and trapezius.
Adopting a slightly more upright torso angle, closer to 45 degrees, tends to increase the involvement of the upper trapezius fibers. Maintaining a strict, parallel torso position keeps the tension localized on the rear deltoids for horizontal abduction. Using a lighter weight and pausing at the top ensures a full range of motion and prevents the use of momentum.