If she is working hard on the treadmill or pumping some iron, don’t stop her from completing her routine. The fact that she is meeting a man should be a bonus, not a distraction from the main reason she came to the gym: to workout.
She doesn’t want to huff and puff just to talk to you (especially if she’s attracted to you. You’ve got to give her a chance to make a good impression on you too).
It might be tempting to take that yoga class with all the cute girls in it, but beware of getting the “creepy guy” vibe. Women are aware of the fact that you are a man and will be checking them out for the duration of the class. If you are not genuinely interested in aerobics or dance or yoga solely for the sake of doing those exercises and not picking up women, then don’t take those classes.
Stick to your routine. Focus on your gym goals more than your pick up goals.
Don’t look at her body if you want her to take you seriously. She could sleep with any of the guys at the gym, so don’t make her feel objectified. She wants to know that you are interested in her for more than her looks, so if you just compliment her beauty, she will be flattered, but she won’t think you’re truly interested and she won’t date you.
Don’t drip sweat when you’re talking to her. Furthermore, use deodorant. Enough said.
Unless she is wearing headphones, open with something indirect and gym related. Talk about how the music in gym is never really the best for working out or how there is always some guy grunting like he is in the movie 300. If she is taking it easy on a treadmill or a bike, say something like “Race you to the finish line.”
If you see a cute girl at the gym in the morning, the middle of the day, or the early afternoon, there are good chances that she has something to do after such as work or school. If you see her in the late afternoon or the evening, she will not be in as much of a rush to finish her workout and therefore, will have more time to talk to you.
There is a great book called Daytime Dating by Jeremy Soul (an essential read if one wishes to get serious about improving his dating life). What Soul suggests is that, when you meet a woman, you should have a normal conversation with her where the two of you get to know a little about each other in a fun and lightly flirtatious way. Find out if she’s the type of woman that you like. You know she’s athletic (or trying to be). Is she a good cook? Is she educated? Does she have a sense of humor? Does she have things going on in her life? Does she have ambitions? If she doesn’t meet your standards, you’ve saved yourself the trouble of dating someone with whom you are not compatible.
If she is the type of girl you are looking for, great. Ask for her number and see if she would like to get coffee or a cup of tea. If she’s artsy, ask her to check out an art gallery or museum with you. Don’t do dinner or a movie on the first date.