In that case, I’d go ahead and tell her. It will be a lot more embarrassing when she has to tell an employee that she broke the machine. (She probably should also turn down her music if she can’t hear the “racket,” but that would fall under the category of unwanted advice. ;))
Unless I knew the OP was working for the gym, this is how I’d feel. Plus, the delivery is very important. If some random guy came up to me and said, “You could be doing that better,” I’d probably ignore him completely. On the other hand, if someone said, “Hey, have you tried it this way?” I’d be more willing to listen.
I understand the OP’s pain. I die a little inside everytime I watch someone clutching a treadmill for dear life while going far too fast or dangling off the bars of a stairmaster. However, knowing how I’d respond to some random person talking to me about my form, I wouldn’t say anything unless it was clearly obvious that an injury was imminent.
I would take equal offense at your suggestions as I would at a man’s … and I would assume you were interested in me. Can you show me how to work this machine…? 
My experience has been that maybe two out of three people that have offered me advice are enthusiastic newcomers who are just repeating something that they heard the other day from someone else. They get a blank stare.
No, I wouldn’t be offended, assuming you were polite and clearly trying to help me out and not hit on me, or just show off how much you knew 
Female and in pretty good shape, I also like to read up on workouts a lot (ie, what works and what doesn’t).
Though if you told me to lift lighter weights with more reps just because I’m a woman, I’d probably just stare at you.
If it’s something that’s possibly damaging to the machine, yes, I would absolutely want to be told. I’d rather be told nicely than have the staff rolling their eyes at me for ruining the equipment. Pls introduce yourself as an instructor at that gym.
A free tip? If it’s something really obvious and makes the whole exercise a waste, then yes, otherwise … maybe. Depends on what kind of mood I’m in. Again, let me know you are an instructor.
Female, I could stand to go to the gym more.
Really? I’ve been using gyms for years, and I’ve never found this to be a problem. Most people don’t even notice what other people are doing, and even if they do, very rarely say anything. I’ve only had one person mention something to me, and she was a trainer at the gym I was using (and yes, I was using the machine wrong, or at least inefficiently).
I’ve had a couple of people give me totally bogus info at the gym. I resent it.
OTOH, if you’re on staff, then that’s different.
I would never say anything unless I thought the person was going to hurt him/herself, and even then, I’d probably try to find a staff member.
If I see somebody doing something really weird, I will assume they have a personal trainer, but are following the PT’s instructions correctly. My trainer had me doing a couple of things differently on the equipment, and people did make suggestions about “doing it right.”
It wouldn’t matter to me what sex you are but I wouldn’t be bothered if you were in uniform and approached me. Thats what gym employ fitness staff for. But if you were working out yourself I might be a little bothered. Or interested in the fact that the gym staff on duty hadn’t bothered or noticed.
Im female, young, and work out every day and run 20km a day.
That’s not too absurd. I can and do break 230 without having the machine in any real danger, but the reason is that I keep the resistance high enough to not throw off the machine’s balance (think of pedaling a bike really fast in low gear vs a high gear).
I’m a safety supervisor, so I make my living by telling professionals that what they’re doing their jobs all wrong. I so have a certain amount of empathy for both the sender and the reciever of advice on technique and such.
While I’m not completely over my head in a gym, I’ll readily admit that I’m, no expert. Therefore, if someone has some advice to offer on how to better use a piece of equipment, I’ll listen to what they have to say. On the other hand, I do know enough about fitness from my years of coaching to know when something I’m doing is correct for my specific goals and so I reserve the right to ignore the advice if it doesn’t apply.
Boy-person, a few days shy of 40, need to drop a few pounds and I’m working half-assedly at it.
230? Really? Are you sure you’re not looking at Watts? That’s almost 4 rotations per second!
I’ve been offered friendly advice a few times and I appreciate the help.
(I’m not a gym goer now - maybe I’d be annoyed if I were hotflashing)
I’m on the fence, because if you’re not a dick about it and you have a valid point, maybe I’d be cool with it.
On the other hand, I can’t even agree with the “unless you work for the gym” viewpoint, because I had a membership at a shit-tastic gym where the days were divided (you’d alternate days, men only and then women only). I’d go to my women only days, with only women trainers who would give the shittiest advice ever!
They still insisted that women only should ever do a brazillion reps with a super low weight. Here I’d be at the seated row, doing my reps at 40 or 60 lbs (and quite able to do at least 8-12) and some worker would just walk right up and say, “Oh NO, honey! That’s toooooo heavy! You don’t want to bulk up! You need to stay at 20 lbs, max!”
Uh, yeah. That’s a waste of my fucking time, you dumb shit. I don’t have the testosterone necessary to “bulk up” (nor am I a lifetime hardcore, say, speedskater). A lot of GUYS don’t have the testosterone necessary to bulk up without juicing. So shut the FUCK UP and LEAVE ME ALONE.
I wouldn’t be offended. I would hope that you wouldn’t be offended if I mention that I have been lifting longer than you have been using the potty by yourself.
I don’t damage the machines (I use mostly free weights), but I lift the way I do for a reason.
The personal trainers at my gym are mostly soliciting business. I don’t need 'em. Thanks anyway. If they start getting snotty, I ask how many different kind of muscle fibers there are. If they say two, fast- and slow-twitch, I tell them to look it up.
Regards,
Shodan
Don’t take this the wrong way, but where does it say anything different in that link?
Right from the first paragraph: ‘There are two broad types of voluntary muscle fibers: slow twitch and fast twitch.’
Are you referring to the sub-types of fast-twitch?
If someone gives me a suggestion on form or use of a piece of equipment, I will take it into consideration, and I hope they aren’t offended if I don’t take it.
If they make some comment about the amount of weight/reps I’m using, they can shove it.
There are only two kinds of muscles - those that can, and those that can’t. 
Yeah, this is it for me too. I’ve offered advice at gyms very occasionally, and only when I see someone doing something potentially damaging. And I guess that even has a sliding scale.
If I saw someone doing a deadlift and lifting with their knees locked using their back, I would probably try to interrupt them in the middle of a set and let them know that it looked like they were going to injure themselves. I’d offer to show them how to do it more safely. If I saw something like a squat where the person was locking their knees, unless it was someone doing a lot of weight (and actually maybe not even then) I might mention that I noticed they were locking their knees and if they were aware of it. Were it someone doing not much weight compared to their body size, I probably wouldn’t mention it at all.
Something aerobic or situp forms or something? Forget it. I don’t want to get involved. Maybe if the person looked really REALLY lost I’d see if they wanted “a tip.”
Note that I am not a professional or certified, but I had to do various lifting for college wrestling, and our wrestling coach was also the certified strength and conditioning trainer for the school. I had to learn to do them correctly, and I can recognize when they are being done incorrectly. Not every lift, mind you, but most of the ones that target large muscle groups we had to do as part of practice.
If you work for the gym, you might have more cause to bring up machine damage, and possibly couch it in terms of fitness. I’d leave pure fitness issues alone though.
Yes, that’s correct. I also ask if I can change fat into muscle. If they say yes, I tell them thanks, but I don’t need their services.
Regards,
Shodan
If the woman was in danger of harming themselves or breaking the equipment, I’d tell the staff. Surely they should be somewhat monitoring the clients to make sure they’re not breaking things. If you are staff, and it’s part of your responsibility to oversee things, then I’d tell her, using the authority of your position. If it’s just a case of “you could maximize your workout”, I’d keep my mouth shut unless my advice was asked for, unless “roving trainer” is your job description.
StG