The best way I can put it is, it should fit like a second set of skin. It will stretch a little yes. I'm 6'2" 220ish and wear a 58 Euro/48US. I wear a Knox Ageis Spine Protector and have no issues at all with the suit and it. You don't want baggy at all or it will flap in the wind and be a major disctraction. It should fit snug to your body, but not circulation restricting. And depending on which suits you were trying on, do research on the exact suit you would wear/are going to buy. I got a Astar Trigger suit, which goes a size big...so its a 56 for me. Just make sure you know what your getting and the sizes it goes.