Blasting music through your headphones, stalking your go-to elliptical machine while you warm up, spritzing perfume post workout… you may not know it, but one of your gym habits could be totally throwing off someone else's workout game.

Here, personal trainers, gym owners, and regular exercisers sound off on 10 of the most common gym gripes. (Get a flat belly in just 10 minutes a day—seriously, this works!—with our reader-tested exercise plan!)

You don't wipe down the machines.

By far the biggest pet peeve, this one isn't just gross, "it's a health hazard," says Jessica Mehta, a yoga teacher from Hillsboro, Oregon. "I've been diagnosed with cellulitis, and my doctor said it was 'probably from gym equipment.' Bring a towel, use the sanitizers, and clean up after yourself." Whether there's visible sweat or not, it's an important step to prevent the spread of germs.

And don't forget about mats or the floor, says Fernanda Gea, an avid CrossFitter and blogger at Lift Laugh Lipstick: "Many people remember to clean their equipment, but they forget to wipe up the puddle of sweat on the floor. We are all doing burpees and push-ups on that same surface, and it's just gross." (See what else crawling with germs with this list of the 10 germiest things at the gym.)

You offer unsolicited advice.

Even if you're trying to be helpful, it's best not to give tips to fellow gym-goers—after all, you don't know the details of their health or fitness levels. "If you are not my coach, don't correct my form," says Gea. "Getting corrected by people you barely know is just plain annoying, and possibly dangerous." (Check out these 7 biggest mistakes weight loss coaches see their clients make.)

Jeanette DePatie, a plus-size, certified fitness trainer from California, says that unwanted encouragement can be just as irritating, not to mention presumptuous. "I can't tell you how many times someone has walked up to me—or my students—and said something along the lines of 'Good for you! Keep at it and you'll lose that bulge in no time!'" she says. "First of all, the size and the shape of my body is none of your concern. Second of all, just because I'm a big girl doesn't mean it's any more laudable that I'm exercising than any one else."

You arrive late to classes.

Not only are you disrupting the other people in Zumba or kickboxing, you're also doing yourself a huge disservice. "When students are late, the instructor doesn't get a chance to check in with them about preexisting injuries and can't provide the modifications that will keep them safe during their practice," says Scarlett Redmond, a CrossFit mobility coach in Los Angeles and yoga advisor for Clothing Shop Online. "They also miss the warm-up, which is an essential primer for any physical activity. You can't jump into pigeon pose without doing a few gentle hip openers first!"

You get in their personal space.

If you see someone with earbuds in, she probably doesn't want to discuss the finale of The Bachelorette with you. And most people prefer to be a machine or two away from others if it's not a particularly busy day in the gym. "It's a bit annoying when there are multiple open treadmills or machines and a person jumps on the one right next to me," says Kyle Kranz, a certified running coach from Rapid City, South Dakota.

And as antsy as you are to do your assisted tricep dips, avoid hovering while you wait. "If the machine is occupied, there is no vacancy! It can be so annoying to have someone standing there waiting for you to finish your reps," says Erica Latrice of New Bern, North Carolina. "I try to put on my serious 'gym face' to make them go away."

You take gym selfies.

Having pride in your appearance and progress is healthy, but limit your camera time if you want to keep your neighbor from rolling her eyes in your direction. "I fail to see how not working out, posing for 15 minutes, and taking 100+ photos just to capture a perfect selfie of you 'working out' is actually benefiting your health," says Lindsay Paulson, a former gym employee who blogs at Run Like A Girl. (Skip the selfie and stay focused with these 4 moves to slim your hips and thighs.)

You don't put things back where you found them.

"There is nothing worse than going to the squat rack and there's a barbell with five plates on each side waiting there for me," says Luke Thornton, fitness expert and trainer for Discount Supplements. "It's simple gym etiquette to put your weights away, whether they are dumbbells or weight plates."

Annoyance aside, leaving heavy plates on could keep another person from using the machine at all. "You might be strong, but the next person might not be and can't move those 45-pound plates," reminds Virginia Kinkel, owner of Bodymass Gym in Arlington, Virginia. "If you can lift it, you can put it away." Same goes for medicine balls, jump ropes, and other workout equipment. Putting these items back in their designated storage areas helps other people find them when they need to use them.

You sing or chat loudly on your phone.

"While we all appreciate a great tune and motivational music, hearing someone next to you singing is not quite the same," says Shaun Zetlin, a personal trainer in New York City. So save the Taylor Swift solos for at home or in the car.

The same rule applies to cell phone chatter—keep it to a minimum, and lower your volume as much as possible. "It's hard enough for most of us to get in the exercise zone, so please don't make it more difficult!" Redmond says.

You hog machines.

Resting or texting your BFF from the rowing machine is a no-no if there are other people who may want to use that piece of equipment next. "It's fine to take a quick break between sets while lifting. It's not fine to sit on a bench and talk on your phone for several minutes," Paulson says. "I guarantee someone else wants to use it."

Even worse? Gaming from the bench: "There's one guy at my current gym who takes his tablet along and plays FarmVille or Candy Crush between sets," saysKevin Graham, a frequent gym-goer in Chiang Mai, Thailand.

You wear perfume.

Yes, wearing deodorant and maintaining good personal hygiene keeps you from smelling up the gym, but stay away from strongly scented products. "Many people are scent-sensitive and don't need to be drowned in perfume while they're trying to breathe, especially at a gym," says Meghan Kennihan, a certified personal trainer and running coach from Western Springs, Illinois.

You compete with the person next to you.

"I'm just a mom trying to stay in shape," says April Jimenez, a regular exerciser from Medford, New York. "But once in a while the person next to me wants to outdo me. He or she gets on the treadmill, checks my speed and then puts his or hers on 10, and doesn't break a sweat or breathe heavily." While it's true that a little healthy competition can motivate you, it's probably not a good idea to race the unsuspecting runner next to you. Save it for your next 5K instead. (Don’t waste your time—these 9 proven ways to lose stubborn belly fat really do work.)

This article originally appeared on Prevention.com.