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  7. Dumbbell Fly

Exercise guide

Dumbbell Fly

  • Intermediate
  • Isolation
  • Rep-based
  • Chest
  • Shoulders

The dumbbell fly is a premier isolation exercise for developing the pectorals by emphasizing horizontal adduction of the shoulder. It provides a deep stretch at the bottom of the movement, which is highly effective for stimulating muscle growth and improving chest width.

Reviewed by the Crucible team · Updated June 2026

Watch the Dumbbell Fly demonstrationGuided video and your full workout live in the Crucible app.

Muscles worked

Primary

  • Pectorals

Secondary

  • Serratus anterior
  • Triceps

Equipment

  • Dumbbell

Setup

  1. Sit on the edge of a flat bench with a dumbbell in each hand resting on your thighs.
  2. Lie back on the bench while bringing the weights to your chest, then extend your arms directly above your shoulders.
  3. Maintain a slight bend in your elbows and turn your palms to face each other in a neutral grip.
  4. Plant your feet firmly on the floor and retract your shoulder blades, pinning them into the bench.

How to do it

  1. Inhale and slowly lower the dumbbells in a wide arc out to your sides until your elbows are roughly level with the bench.
  2. Keep the slight bend in your elbows constant throughout the descent to ensure the tension remains on the chest rather than the joints.
  3. Exhale and use your chest muscles to reverse the movement, bringing the weights back to the starting position in the same wide arc.
  4. Stop the weights just before they touch at the top to maintain constant tension on the pectorals.

Form checklist

  • Keep a slight, fixed bend in the elbows; do not allow the movement to turn into a bench press.
  • Maintain retracted shoulder blades throughout the set to protect the anterior deltoids.
  • Avoid lowering the weights too far past the level of your torso to prevent excessive shoulder strain.
  • Ensure your feet stay flat on the ground to provide a stable base for the movement.

Pro tips

  • Imagine you are hugging a large tree or a barrel to maintain the correct circular arc and maximize pectoral engagement.
  • Focus on 'squeezing' your biceps against the sides of your chest at the top of the movement to achieve a peak contraction.

Make it harder

  • Incorporate a 2-second pause at the bottom of the movement to increase time under tension during the maximum stretch phase.
  • Slow down the eccentric (lowering) phase to a 4-second count to further challenge the muscle fibers.

Frequently asked

What muscles does the dumbbell fly work?
The dumbbell fly primarily targets the pectorals, and also works the serratus anterior and triceps as secondary muscles.
What equipment do you need for the dumbbell fly?
The dumbbell fly uses dumbbell.
Is the dumbbell fly good for beginners?
The dumbbell fly is rated intermediate. Build a base with simpler variations first, then progress to it with light load and strict form.

Related exercises

  • Air Punches MarchBeginner · calves, pectorals, and quadriceps
  • Alternate Front Kick In Place With Arm CirclesBeginner · abs, calves, deltoids, and pectorals
  • Archer Push-UpAdvanced · pectorals
  • Arm CrossoverIntermediate · deltoids and pectorals

Train this with a plan, not guesswork

Crucible builds the dumbbell fly into a precise program around your body, equipment, location, and time.

Download on the App Store