Lie down on a decline bench and position both dumbbells right above your chest with your palms facing in and arms slightly bent. This is the starting position.
Lower the dumbbells down until your upper arms are parallel to the floor. Then, raise the dumbbells back up to the starting position and repeat movement for the prescribed number of repetitions.
DO
DON'T
Perform this exercise in a smooth and fluid motion
Don't lower the dumbbells too far down
SPECIAL NOTES & LEVEL of DIFFICULTY VARIATIONS
To increase the level of difficulty, increase the weight or slow down the movement.
This is one of the most relevant exercises for your inner chest area. It will give you the much-coveted superhero-look to your chest - or should we say chest plates! It's not a movement that is designed to pack on mass - it's an exercise that will give you a nice line right in the middle of your chest and will separate and outline your pecs very nicely.
Thus, keep your focus on executing the movement properly rather then going really heavy with the weight. It's a finesse movement and such movements rely on proper pace and execution to be effective.
This exercise is one that you should use when you're on a muscle definition or toning cycle. If your goal is building muscle mass onto your chest, you should do dumbbell presses instead of flys.