Exercise Profile
  • Target Muscle Group
  • Exercise TypeStrength
  • Equipment RequiredDumbbell
  • MechanicsIsolation
  • Force TypePush (Unilateral)
  • Experience LevelBeginner
  • Secondary Muscles
    Shoulders, Triceps
Target Muscle Group


Chest Muscle Anatomy Diagram

One Arm Dumbbell Fly Overview

The one arm dumbbell fly is a unilateral variation of the dumbbell fly. It is used by those who would like to focus on one side of their chest working at a time.

When performing the one arm dumbbell fly, it is important to start off with the weaker side of your chest. While the pec you’re not working will be recovering while performing the one arm dumbbell fly, it makes sense from a conditioning standpoint to work the weaker side first.

One Arm Dumbbell Fly Instructions

  1. Pick up the dumbbell off the floor using a neutral grip (palms facing in). Position the end of the dumbbell in your hip crease, and sit down on the bench.
  2. To get into position, lay back and keep the weight close to your chest. Once you are in position, take a deep breath, then press the dumbbell to lockout at the top.
  3. Slightly retract your shoulder blade, unlock your elbow, and slowly lower the dumbbell laterally while maintaining the angle at your elbow.
  4. Once the dumbbell reaches chest level, reverse the movement by squeezing your pec and bringing the dumbbells back to the starting position.
  5. Repeat for the desired number of repetitions on both sides.

One Arm Dumbbell Fly Tips

  1. Imagine you’re trying to hug a tree while completing the exercise.
  2. Don’t squeeze the dumbbell handles excessively tight as this can over recruit the forearms and biceps thereby reducing activation of the pecs.
  3. Place your free hand on your ribcage to monitor spinal positioning or on your pec to improve mind/muscle connection through proprioceptive touch.
  4. Always keep a slight bend in the elbows and never lower the weight to the point where you get any sort of pain and pressure at the front of the shoulder joint.
  5. If you’re feeling pain within the shoulder joint itself (specifically at the front), ensure your shoulder blades are slightly retracted and try to keep the shoulder girdle “packed”.
  6. Keep your feet flat on the floor, focus solely on keeping your elbows bent and activating your pecs.
  7. Ensure you maintain some tension in your abs and don’t allow your lower back to excessive arch.