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Popular Workouts That Can Wreck Your Body, According to Experts

Avoid these exercise no-nos to ensure your own personal safety, advise top trainers and doctors.

Before we explain why you shouldn't do some workout moves, there's one thing we need to get out of the way first: When you perform any sort of exercise, both your ability level as an athlete and proper form are paramount. "After all, there's really no such thing as workout moves that damage your body," says Eni Kadar, PT, DPT, Cert. DN, an orthopaedic physical therapist based in Florida. "Only bodies that are not ready for the forces applies to them or poor technique. Our bodies were made to move."

That being said, if you're an average athlete, there are a number of exercise moves that you'd be wise to avoid for the sake of your health and your safety. We're talking about way overdoing it with your cardio, adding unnecessary additions to your bike rides that expose you to injury, and doing some high-level weight lifts that, when performed less than perfectly, can actually crack parts of your vertabrae. (Yikes.)

We reached out to several top doctors, trainers, and other experts to learn the popular workout moves that have the potentially to really wreck your body. Below are their responses. So read on, and remember to practice proper form at every turn. And for some top-level fitness instruction you can use now, consider trying The 10-Minute Total-Body Workout That Will Transform Your Body Fast.

Straight Bar Curls

straight bar curl

If you let your arms hang loosely by your sides while performing this arm lift, you'll notice that your palms face inward. The problem with straight bar curls is that they lock your arms into an unnatural palms-up position. "In so doing, you're stressing your elbow joints, and that can lead to tendinitis," says David Pearson, Ph.D., a professor of exercise science at Ball State University. A safer alternative is to try E-Z Bar Curls, where the bar is angled to put your elbows in a more natural neutral position. And for more exercise advice, make sure you're aware of the One Major Side Effect of Going for a Single 1-Hour Walk, Says New Study.

Working out your upper body while cycling.

spin class

If you love a spinning class, chance are you've had more than one instructor who wants you to exercise your upper body while you're pedaling. Many experts disapprove. "Trying to workout your upper body while riding a stationary bike is hazardous and has little to no benefits," says Garret Seacat, C.S.C.S., a trainer and endurance coach. "When you are bobbing up and down on a bike doing push-ups or any kind of upper body workout while pedaling, you increase your chances of injuring your lower back dramatically."

Also, the effort you are putting into the pedals drops, which lowers your power output and makes the workout even less effective. "If you want that upper body workout, take the time after the ride to do some pushups on the ground while you are stretching and cooling down," he advises.

Posterior (behind-the-neck) pull downs

posterior pull downs

This exercise rotates your shoulders into a position that strains your rotator cuffs, paving the way for inflammation. "I've also seen guys pull the bar down so fast that they crack their spinous processes [little nubs on top of the vertebrae]," says Pearson. And for more news from the front lines of health and fitness, see how Drinking This 30 Minutes Before Exercise Torches Fat, Says New Study.


sit ups

Not only are sit-ups bad for your neck, but they're also one of the least-effective abdominal exercises you can do, according to a study at San Diego State University. "Repeated spine flexion, like in a sit up, has been shown to cause disc herniations over time and creates a lot of compression and shear force across our lumbar discs—over and over again," says Seth Hampton, PT, a physical therapist and spine specialist.


man doing dips outside

"I recommend staying away from the dip station if you do not know what you are doing," says Christina Widmark, a personal trainer, competitive powerlifter, and owner of Bare Fit USA. "Hyperextending your shoulders can lead to torn ligaments and permanent injury. Dips need total control—no swinging around."

Leg extensions

leg extensions

The four parts of your quadriceps are designed to work together as one, but a study in Medicine & Science in Sports & Exercise found that leg extensions activate the sections slightly independently of one another. Even a five-millisecond difference can cause uneven compression between the kneecap and thighbone, inflaming the tendon that connects the kneecap to the shinbone (a painful injury known as jumper's knee). It's safer to do squats, where you safely place the bar across your shoulders (not your neck) and keep your back straight, bending slightly at the hips through the squatting motion. Proper form is crucial with this exercise.

Running way too far.


"You may think that increasing your running time might lead to greater endurance, stronger muscles, improved heart health, and more confidence," says John Fawkes, an NSCA-certified personal trainer and Precision Nutrition-certified nutritional counselor. "While this may be true to some extent, studies show that running too far can cause negative effects to your cognitive health. One study conducted by Germany's University Hospital of Ulm found that running long distances shrinks the brain by 6%."

Fawkes notes that your brain consumes roughly 20% of your energy stores to function. "Push yourself on a long run—like ultra-marathoners do—and you'll deplete your brain." For more science news, learn What Walking for Just 20 Minutes a Day Does to Your Body, According to Science.

Dumbbell chest fly

dumbbell chest fly

"One of the most common (but still dangerous) exercises I see performed in the gym is the dumbbell chest fly," says Joshua Lafond, a certified NASM Personal Trainer. "First and foremost, it looks easy to perform, which can lead to an increased potential for injuries because people will begin performing the exercise without learning the proper technique first. Also, many people add too much weight and therefore fail to keep their elbows at a fixed angle which can overextend the shoulder joints. This hyperextension can be detrimental to a person's shoulder joints, which are one of the most sensitive in the body and can take months to heal if injured."

152 Minutes of HIIT in a Week

hiit workout

According to a new study just published in the journal Cell Metabolism, taking your interval training to the extreme can impact your metabolism. Study participants who performed a grueling 152 minutes hardcore HIIT experienced a drop in their mitochondrial function, the cellular process that burns calories. Not only that, but the exercisers' insulin resistance actually went up. "It's quite similar to the changes that you see in people that are starting to develop diabetes or insulin resistance," the study's lead author explained in an interview with The Scientist. And for more great exercise advice, make sure you're aware of the One Major Side Effect of Sitting on the Couch Too Much, Says New Study.

William Mayle
William Mayle is a UK-based writer who specializes in science, health, fitness, and other lifestyle topics. Read more about William
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