Last week, I went to my usual morning Spin class, and a new instructor I’d never seen before was subbing in. Next to me was a newbie rider. The instructor helped her set up her bike and gave her the rundown on hand positioning. We warmed up, then launched into our first all-out sprint—with the teacher yelling, “Push it, push it, push it! Come on! Just 40 more seconds! Don’t slow down now!” My neighbor made a strange sound. I glanced over just in time to see her eyes roll back in her head and her body start to go Jell-O. She hit the brake and got off the bike before totally keeling over, breathless, pushed a bit too far by the pushy instructor.

“I think teachers take for granted that their riders have the same fitness level and musculature that they do, so there’s this disconnect where they think, oh sure, everyone can run up in third position at extremely high speed and be totally fine,” says Adam Wasserman, a master instructor at Flywheel in New York City. That’s one instance when you absolutely can—and should!—ignore what the teacher is telling you. Here are 12 other bogus cues you might hear, from all sorts of group fitness disciplines.

CrossFit & Bootcamp

“Give me 15 reps!”

There’s nothing inherently wrong with that number. It’s just that it’s totally arbitrary, according to exercise physiologist and fitness instructor Pete McCall, a spokesperson for the American Council on Exercise. “If you’re trying to improve your fitness, you have to work to fatigue,” he says—and the number of reps you need to accomplish that is pretty personal. “For some people in the class, that might be 10 reps, for others it may be 17. Ideally, instructors will give you a rep range to aim for. Otherwise, you may be doing too much, or not enough.”

“Go heavy or go home.”

If you’re used to swinging a 40-pound kettlebell around, then by all means, power to you! But don’t let an instructor push you (and they sometimes do) into heavy lifting if you usually go a lot lighter. Your form will suffer, and it may well lead to injury—or at the very least, miserable muscles the next day. “Your body needs about 6 to 8 weeks to get strong enough to bump up the amount of weight you use,” McCall says. “So don’t rush it.” At the same time, many people—especially women—underestimate the amount of weight they can lift out of fear they will get “bulky.” (It’s not gonna happen.) If you’re really confused, pull the instructor aside before class and ask for a recommendation based on your experience.

“Pain is weakness leaving the body.”

You hear this a lot in high-intensity classes like CrossFit—I mean, this phrase is on t-shirts! But it’s not a mantra we want to hold onto,” McCall says. “Pain is a sign of something going wrong.” It’s fine to push yourself to the point of feeling uncomfortable—that is how progress is often made. But actual pain? No. Just no.

Indoor Cycling

“Use your forearm to measure your seat distance.”

EDITOR’S PICK{{displayTitle}}Back in the day, this cue was given to help a rider know how far back to move their seat from the handlebars so their knees would be properly aligned. “It’s an old relic of an idea, and it couldn’t be more wrong,” Wasserman says. “It will place the seat too far back.” The right how-to: The seat should be at a distance where your front kneecap is directly over the ball of your foot when you’re in the saddle and the pedals are even.

“Move to the beat of the music.”

That’s instructor-speak for: Pick up the pace! “But if the speed is too excessive for you—particularly if you’re riding out of the saddle—ignore it,” Wasserman insists. “Find what feels like the right amount of work for you and stick to that tempo.”

“Reach your hands out to 3rd position.”

“You hear this lingo all the time, and it’s really misleading because it makes you move your hands before your butt comes out of the saddle,” Wasserman says. “As soon as you start to reach forward, you’re not able to engage your core, which can compromise your lower back as well as throw off your balance.” The real key, he says, is to lock down your abs, then lift your hips first, before reaching for 3rd in one swift motion.

Pilates & Yoga

“Inhale to X, and exhale to Y.”

Both Pilates and yoga are super focused on the breath—almost to a fault, according to Kristin McGee, a celebrity yoga and Pilates instructor in New York City. “Sometimes people get so caught up with the inhales and exhales that they hold their breath because they don’t know what to do,” she says. “So I often tell people: Just breathe. It doesn’t matter how you do it. As long as you’re breathing, you’re doing OK!”

“Keep a neutral spine.”

Honestly, how many times have you heard Pilates instructors say this? (Meaning: Keep a slight arch in your back, versus imprinting your spine on the mat.) “But in the beginning, many people don’t have the core strength to maintain a neutral spine, and it strains their lower back,” McGee notes. And if you have existing low-back issues—regardless of your fitness level—a more flat-back approach is probably better for you, she says. “If a teacher keeps harping on it, I’d blow it off and just keep doing whatever feels right to you.” If you explain your condition and they won’t let it go, it’s not the right studio or instructor for you.

“Don’t break for water until class is done.”

It’s taboo among some yoga instructors, particularly Bikram teachers. “I have gotten dirty looks for stopping to take a drink of water,” McGee says. We’ve even heard of this happening in indoor cycling classes as well. “But if you’re perspiring in a 120-degree room and aren’t allowed to have water—seriously?!—there’s something wrong with that.” And people feel so intimidated that they don’t stop, which of course, could lead to a dangerous situation. Drink up, no matter what. If you don’t want to deal with the side-eye, step out of class for a moment while you rehydrate.

Bodyweight Training

“Don’t let your knee go past your toes.”

This one is commonly called out during lunging or squatting, but unless you have knee problems, this isn’t a problem. And depending on the actual length of your bones, going into a nice, deep lunge or squat may necessitate it. “If you look at most Olympic lifters, their knees are jutting way out past their toes,” McCall notes. A better cue, he says, is to think about sinking into your hips: “The first movement should be your hips going back and down, not your knees shifting forward.”

“Lift your shoulder blades off the ground.”

A classic crunch cue, right? But here’s the thing: “It makes you engage your shoulders and neck, rather than your abs,” McCall says. He recommends thinking about bringing your ribcage toward your pelvis—and placing your hands on the bottom of your ribs, so you can really feel your abs contracting.

Barre

“Tuck your pelvis under.”

EDITOR’S PICK{{displayTitle}}“This is an alignment cue you hear a lot, and instructors often exaggerate the form when they demonstrate it and really C-curve their pelvis forward. But they don’t really mean slam your hips forward. It’s more about getting you to not arch your back and maintain more of a straight spine,” says Kara Liotta, head of Flybarre at New York City’s Flywheel. Ballerina stance (long, tall, impeccable posture) is what you’re going for.

“Lock out your arms.”

This one’s just a total misnomer. “The instructor isn’t asking you to really lock out your arms or your knees—what they actually mean is straighten them,” Liotta says. Here’s the problem: For hypermobile people whose bodies can bend beyond this point, locking out your joints will place too much strain on them. If you’re super flexy, the next time you’re instructed to do this, just mentally translate those words as “straight” and know that that might mean micro-bending your elbows or knees to protect your joints.