I've done it, here's the deal: just say hi. Its that simple, ask them how're they're doing. sometimes they feel like pieces of meat and are tired of constantly getting hit on. if you don't hit on them and just seem nice, they'll looking at you differently because you're not hitting on them. But, they might try to blow you off still. this is the point where you will quickly find out if they're a bitch or just wary of dudes. If they blow you off, call them on it. say," wow... just saying hello, don't flatter yourself," raise your eyes and walk away. you're in command. they're the jerk at this point. A friendly hot gym chick or low self esteem hot gym chick does not like the idea of being disliked by anyone and will either say something back to you right then or will say something to you later. If this happens, seem a bit aloof, yet receptive to her talking to you. If the bitch blows you off completely and never says anything later... shes a complete bitch and you don't want anything to do with her. She's either taken, a daddy's girl with too much money, dumb as rocks or a complete bitch. But now you've got to make that bitch feel inferior. wait for another attractive girl to be right next to her and talk to her instead of the bitch. Don't go too far out of your league though.