The same way you'd feel annoyed if a stranger interrupted you while you were repping squats, or in between sets of reverse flys...
(Or at the least, you'd wonder, “why is this weirdo bothering me?”)
Girls at the gym don't want to be approached during their workouts!
As a general rule of thumb, it's generally wise to avoid approaching women on the gym floor entirely —
Even if your crush isn’t actively exercising, she may be in the zone, and unreceptive to interruptions.
Many women, myself included, don't feel attractive while they're working out.
Women often have headphones in, anyway, and headphones in = do not disturb whether you're at the gym or anywhere else.
☝ This isn't to say it's never OK to approach a girl on the gym floor.
For example, if she's working out right next to you, and you've already smiled at each other, by all means start a conversation!
It's just usually better to approach after your workouts, for example:
At the smoothie bar. Try paying her a genuine compliment like, "Did I see you crushing it over at the squat rack today?" and maybe you even continue the conversation over your drinks.
Exiting the gym. For example, maybe as you're walking to your cars, you say something like, "Hey, I'm Blaine. I just wanted to say hello because I see you here often. What's your name?"
To increase the likelihood she wants to talk with you...
Create a non-verbal connection while you're on the gym floor, by smiling and making eye contact, first!
Her response (i.e. does she smile back?) tells you everything you need to know about whether she’s receptive to chatting, plus it gives you an excuse to approach later — you can literally say, "Hey, we made eye contact earlier, and I wanted to introduce myself..."
Just remember not to stare.
If she notices you're continuously looking over at her during your workout, she'll probably feel uncomfortable.
2. Create friendly rapport before asking her out
Now that you've worked up the courage to approach your gym crush, and you're coincidentally walking out of the lobby at the same time...
❌📲 Don't ask for her number quite yet!
The gym is a special place for women.
The last thing a girl wants is to feel uncomfortable about visiting because she gets unwanted attention in the parking lot...
Instead of asking for her number, simply introduce yourself.
Have a friendly conversation, enthusiastically say, "I'll look forward to bumping into you again sometime!" and part ways.
You increase your likelihood of successfully sparking romance 100x by waiting to ask for her number until your second or third conversation because it shows you're socially intelligent:
You're aware the gym isn't a place girls expect (or want) to be hit on
You're not so desperate that you ask girls out before you've learned whether you have a connection
Once you've chatted in a friendly way once or twice, you ask her out by saying something like:
"You have great energy, and I love chatting with you — what would you think about grabbing a drink outside of the gym sometime?"
Still not sure how to just break the ice?
You don't need to say anything fancy. Here are two more strategies you can try:
If you made eye contact on the floor... Mention it! Just say something like “Hey, I think we made eye contact on the floor earlier, and I just wanted to say hello…”
If you attended a class together... Ask her what she thought of the workout. Say something like “What'd you think of that class? Those deadlifts kicked my ass...”
On this note...
Group fitness classes tend to be easier places to meet women than regular gyms, because usually there's some socializing baked in (e.g. meeting your neighbor before class).