One Arm Rear Delt Dumbbell Row

The one-arm rear delt dumbbell row is a unilateral back exercise performed by rowing a dumbbell from a bent-over, three-point stance to target the posterior deltoid and mid-back musculature. Training one side at a time exposes and corrects strength imbalances between limbs while improving scapular control. Because the elbow flares out and back rather than tucking to the ribs, the movement biases the rear delts and rhomboids more than a standard lat-focused row. It's commonly used to build posture-supporting upper-back strength and to prepare the shoulders for pressing work.

Muscles Targeted

• Primary: Posterior deltoid (rear delt), rhomboids
• Secondary: Middle trapezius, latissimus dorsi
• Tertiary: Biceps brachii, forearm flexors, core stabilizers

Starting Position

Place one hand and the same-side knee on a flat bench so your torso is roughly parallel to the floor with a neutral spine. Stand on the opposite side with that foot planted firmly on the ground, holding a dumbbell in the free hand with the arm hanging straight down from the shoulder. Let the shoulder blade protract slightly at the bottom so the arm reaches its full length before you begin.

Execution Steps

1. Brace your core and lock the bench-side arm to keep your torso stable in a flat, horizontal position.
2. Initiate the pull by drawing the working shoulder blade back and down before bending the elbow.
3. Row the dumbbell up and slightly out toward your hip, leading with the elbow rather than the hand.
4. Squeeze at the top, bringing the elbow just past your torso and pausing briefly for maximum rear delt contraction.
5. Lower under control back to full arm extension, allowing the shoulder blade to protract again.
6. Complete all reps on one side before switching hands and repeating on the opposite side.

Form Cues

• Lead with the elbow, flaring it out and back at roughly 30-45 degrees from the torso to bias the rear delt over the lats.
• Move the shoulder blade through its full range - retract at the top, protract fully at the bottom.
• Keep hips and shoulders square to the floor; don't rotate the torso to help lift the weight.
• Row to a moderate height near the hip or lower ribs, not straight up to the chest.
• Keep your neck neutral, eyes toward the floor, rather than craning forward to look ahead.

Common Mistakes

• Using too much weight and rotating the torso to move it: this substitutes momentum for muscle work. Reduce the load and keep the shoulders square.
• Tucking the elbow tight to the body: this shifts emphasis toward the lats and biceps instead of the rear delt. Keep the elbow flared out.
• Rounding the lower back: a rounded spine reduces stability and stresses the low back. Keep the back flat and core braced throughout.
• Yanking the weight up explosively: jerking the dumbbell reduces time under tension and control. Row with a deliberate 1-2 second concentric.
• Shrugging the shoulder instead of retracting the shoulder blade: this overworks the traps and understimulates the rear delt. Retract the scapula before bending the elbow.

Variations

• Bent-over dumbbell reverse fly: removes the elbow-driven pull for a straighter-arm movement that further isolates the rear delt.
• Cable face pull: provides constant tension plus an external rotation component for the rear delt and rotator cuff.
• Chest-supported rear delt row: eliminates lower-back stabilization demands by supporting the torso on an incline bench.
• Resistance band pull-apart: a light, joint-friendly option for warm-ups or high-rep finishing work.
• Two-arm bent-over row, wide grip: trains both sides simultaneously with a similar rear-delt emphasis.

Tips for Progression

• Increase weight in small 2.5-5 pound increments once you can complete 12-15 controlled reps per side.
• Add a 1-2 second pause at the top of each rep to increase time under tension without adding load.
• Progress from bench-supported to standing bent-over rows to add greater core stability demand.
• Build total weekly volume by adding a set before increasing the weight.

Training Notes

Program the one-arm rear delt dumbbell row 2-3 times per week as an accessory movement after primary back or shoulder compound lifts. Work in the 10-15 rep range with a light-to-moderate dumbbell, resting 45-60 seconds between sides. It pairs well with pressing days as a shoulder-health movement or with pulling days as a rear-delt and posture finisher.