Dumbbell flyes or Chest Presses Which one is best?
I'd stick with dumbbell flyes instead of cable flyes - it'll help break down the fibres more efficiently. And another note on flyes: don't bring the dumbbells too close together because your pectorals literally shut off and you're only working the deltoids. My friend who is a chiropractor and I came up with this idea and tested it repeatedly. So, as soon as you feel the tension in your pecs dissipate you know you've gone to close together during the concentric phase; rather, find the sweet spot and go back down eccentrically and power up explosively.
No. For
flat chest presses with the dumbbells you'll want full ROM. You do want
to "spiral" the shoulders back and in to activate latissimus dorsi to
aid in the lift, thereby allowing more weight to be used.