The 6 Biggest Mistakes Trainers See You Making at the Gym

Tips from trainers

Ever wish you could eavesdrop on the personal training session taking place across the weight room and snag some inside “gym-formation”? Then listen up: We asked five top-tier fitness experts what mistakes they see many of us making. It turns out, the adjustments they recommend are surprisingly easy. Adapt these simple improvements for a cranked-up calorie burn (no extra gym hours necessary) and pain-free workout—you’ll see results fast.

You lean on the machine too much

Nope, not figuratively. If you’re literally resting on the handles while you pedal up a dust storm, your lower body isn’t working as hard as it could be—and that means fewer calories torched, says Michele Olson, PhD, professor of exercise physiology at Auburn University in Alabama. Plus, you won’t effectively engage your glutes and core.

Worse, you could be setting yourself up for injury, because the muscles and joints in your shoulders and neck are forced to support much more weight than usual. “When you lean on the machine, you’re transferring about 30% of your body weight to your arms, shoulders, and neck,” says Olson. “If you weigh 145 pounds, that’s nearly 50 pounds.” Touch bike or treadmill rails with your fingertips for balance, and actively pump your arms if you’re on an elliptical.

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You’re breathing all wrong

“Most people’s breaths are too shallow, at rest and during a workout,” says Beth Jordan, a personal trainer and spokesperson for the American Council of Exercise (ACE). Deep breathing recruits more of the oxygen your muscles need to function efficiently while exercising. With shallow breathing, you’ll notice that your chest rises and falls; deep breathing moves your belly. The timing matters, too: Breathe out on the exertion part of the movement. The exhalation helps push, pull, or rotate the body. “People have a tendency to hold their breath at strenuous points,” notes Jordan. “This limits oxygen delivery to the brain and can cause dizziness or a spike in blood pressure.”

On a run? Exhale as your foot strikes the ground, not before. Your diaphragm relaxes when you breathe out, so your core isn’t as stable, says Jordan—and you don’t want to land at your body’s least stable moment. Change up which foot hits the ground as you exhale. Otherwise, “it’s like wearing a heavy backpack all the time on your left shoulder instead of equally across both shoulders,” explains Jordan.

You shouldn’t “HIIT” it hard every day

HIIT (high-intensity interval training) melts lots of calories in a short amount of time. But like most wondrous things in life (Louboutin heels, ice cream), it’s better in moderation. HIIT requires powerful effort—think 8 or 9 on the exertion scale—leaving your muscles stressed afterward. Do HIIT days back-to-back and your muscles will remain in a broken-down state (and more susceptible to a longer-term injury). “Your muscles repair and strengthen during the hours after the workout,” says Cris Dobrosielski, a spokesperson for ACE. “You should wait about 48 hours before doing another HIIT session.”

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You’re only working your mirror muscles

Don’t neglect muscles like the erectors, which help lengthen the torso, and the rhomboids and external rotators of the shoulder. “Skip these and it’s only a matter of time before you get a back or shoulder injury,” warns Dobrosielski. Do “pulling” moves (like bent-over rows) at least as often as you do “pushing” ones (think chest presses), which target your front.

Also, add back extensions to your routine: Lie face facedown, arms by sides and slightly off the ground, palms up. Raise your trunk a few inches and rotate your palms to face down; pause, then slowly lower. Do two sets of 15 reps.

That cardio rut is bad for your body

Spin may be your true love, but you should have mini affairs with other heart-pounding workouts. “Most of the cardio we do is only forward and backward,” explains Fantigrassi. “When muscles on one side of a joint are strong and the opposing muscles are weak, it can destabilize the join”—and lead to injury.

The fix: Combine cardio workouts that put your body in different plans of motion; for example, jog for 10 minutes, row for 10 minutes, and then do a few minutes of plyometrics, like jump lunges. Mix it up and your joints will thank you.

You should baby your hip flexors

Sitting for long hours tightens your hip flexors (the muscles above your thighs that let your legs bend toward your body). The tension is a precursor to posture problems and an achy back, says Mike Fantigrassi, director of professional services at the National Academy of Sports Medicine.

Loosen your hips using this kneeling hip stretch: Kneel on left leg, with right leg bent at 90 degrees in front of you; place right hand on right hip and raise left arm (A). Contract glutes and shift forward, then rotate hips to the left until you feel a stretch in the front of pelvis (B). Hold for 30 seconds, then switch sides.

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There’s a reason why you’re not losing weight

Your boot-camp class won’t change the number on the scale if you’re committing these errors outside of your sweat sessions:

You think about burn only in the gym: “You get strong in the gym—but you get lean in life,” says celebrity trainer Harley Pasternak, who encourages his clients to wear pedometers and log more than 10,000 steps per day.

You aren’t food-focused: A recent study in Current Biology suggests there’s a limit to how many calories we burn through physical activity; after torching more than a moderate amount, our bodies make it hard to let precious energy go. The fix is in the kitchen: “To drop 1 to 2 pounds a week, cut about 2,000 calories weekly through diet and exercise,” says Jordan.

You’re not as active as you think: One study out of York University in Toronto found that even when people were told what “vigorous” exertion should feel like, they still underestimated how much effort a physical activity actually required. A heart-rate monitor can help give you a more realistic idea of your effort and burn.

This article originally appeared on Health.com