Smart Workout Diary

Dumbbell Decline One-Arm Fly

The dumbbell decline one-arm fly is a unilateral chest isolation exercise performed lying on a decline bench. It primarily targets the lower chest while the shoulders and arm muscles stabilize the weight. It can help develop chest muscle control, symmetry, and hypertrophy when performed with a controlled range of motion.

Demonstration

Dumbbell Decline One-Arm Fly — demonstration 1
Dumbbell Decline One-Arm Fly — demonstration 2

Instructions

  1. Set up on a secure decline bench with your feet anchored. Hold one dumbbell above the working-side chest with a neutral wrist and a softly bent elbow; keep the other hand on the bench or a secure handle for support.
  2. Brace your core, retract your shoulder blade gently, and keep your chest lifted without excessively arching your lower back.
  3. Lower the dumbbell in a wide arc toward the side of your chest. Maintain the slight elbow bend and stop when you feel a comfortable chest stretch and can keep the shoulder stable.
  4. Raise the dumbbell along the same arc until it is above your chest, squeezing the chest without forcefully locking the elbow. Complete the repetitions, then change sides.
Muscle Group
Lower Chest
Type
Strength
Mechanics
Isolation
Equipment
Dumbbell, Bench
Difficulty
Intermediate

Technique tips

  1. Use a light load. The long lever makes this exercise demanding on the shoulder despite using one dumbbell.
  2. Keep the elbow angle consistent. Bending and straightening the elbow turns the movement into more of a press.
  3. Control the bottom position. Do not force depth or let the dumbbell pull the shoulder forward.
  4. Breathe steadily. Inhale as the dumbbell lowers and exhale as you bring it back over the chest.
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