Muscle Group: Chest
These pack mass on quickly to the pectorals. The focus is almost entirely on the stretching portion of the exercise, which expands the fasciae and allows for a greater muscular growth. I also find that several times athletes rest at the top range of motion when performing flys. Essentially leaning the dumbbells on each other for support.
Partial Dumbbell Flys eliminate this and provide continuous tension on the pectorals. I will often rotate between traditional flys and partial flys. Changes like these amount to continuous growth. I may even switch as often as every week, or combine them both in a workout.
Lie back on a flat bench holding dumbbells at straight above You with your arms fully extended, your palms should face each other.
Now lower the dumbbells out and downward to either side using an arcing motion. Keep going till you feel a maximum stretch at the bottom. Bend your arms a bit as you perform this exercise so as not to stress out your elbows. Bring the dumbbells to a complete stop when your pecs are completely stretched out. Now raise the weights back up along using the same arcing motion as when You lowered them. The key here: Stop when you are about 8-12 inches from a peak contraction, then lower again. The emphasis should be on the stretch!