Dumbbell Fly
Master the dumbbell fly with a controlled arc to stretch and strengthen the pectorals safely
Watch animated demo (GIF)How to perform
- Lie flat on a bench holding a dumbbell in each hand with your palms facing each other.
- Start with your arms extended straight above your chest and a soft, fixed bend in your elbows.
- Inhale and lower the weights out to the sides in a wide arc until you feel a stretch across your chest.
- Pause for a moment in the stretched position, then reverse the arc and bring the dumbbells back together as you exhale.
- Keep the bend in your elbows constant throughout, and repeat for the desired number of reps.
Muscles worked
The dumbbell fly is an isolation movement for the chest, built around hugging the arms together against resistance. The front shoulders help stabilize the path of the weights, but the pectorals do nearly all of the work.
- Pectorals — stretch and contract to draw the arms together
- Anterior deltoids — stabilize the shoulders through the arc
- Coracobrachialis — assists the chest in pulling the upper arms inward
Make it easier
Use lighter dumbbells and shorten the arc so you only lower the weights to chest level. Cable or band flies done standing give you more control over the resistance curve.
Make it harder
Slow the lowering phase to a 3–4 second count and pause at the stretch, or perform the fly on an incline to shift work to the upper chest. A drop set, finishing with lighter weights, adds volume without breaking form.
Common mistakes
Mistake: Using too much weight. Fix: reduce the load so you can control the entire arc without dropping the dumbbells. Mistake: Bending and straightening the elbows mid-rep. Fix: lock in a slight bend and keep it fixed for the whole set. Mistake: Letting the shoulders roll forward. Fix: keep your shoulder blades pinned to the bench and your chest lifted.
FAQ
Should I use heavy dumbbells for the fly?
No, the fly is a stretch-focused isolation movement, so control matters more than load. Choose a weight that lets you complete the arc without letting the dumbbells drop below chest level.
Why keep a slight bend in the elbows during the fly?
A fixed, slightly bent elbow turns the arms into levers and keeps the load on the chest instead of the shoulder joint. Straightening or bending the elbows mid-rep turns the fly into a press.