11 Exercises that Do More Harm Than Good

Now that you're building a healthy body with a steady gym routine, do yourself a favor: Don't waste time with ineffective or downright dangerous moves. We'll tell you which exercises to skip.

Seated hip abductor machine
You think you're working the outer thighs in hopes of blasting away those saddlebags. Unfortunately, the bad news here is twofold: When you're seated in this position, the abductor muscles of the outer thighs aren't actually doing the work. Instead, the piriformis muscle, a small deep hip muscle, is. And when this guy is worked too hard, it can get angry and pick on its neighbor, the sciatic nerve, possibly leading to painful sciatica.

Besides, you can't blast away fat on a specific body part - better known as spot reduction - by working just those particular muscles anyway. "This machine totally ingrains that myth," says Irene Lewis-McCormick, MS, CSCS, a personal trainer in Iowa. The only way to reduce trouble spots is by changing your diet and doing total-body exercises that peel away pounds from your entire frame.

Crunches
If your aim is to strengthen your core, listen up: You never again have to do an abdominal crunch. "This motion puts you in spinal flexion, and reinforces the bad slouching posture that people fight against all day when sitting in a chair," says McCormick. Furthermore, it emphasizes the incorrect notion of spot reduction. Remember, no amount of crunches will blast away belly fat. Focus on firming your body from head to toe.

Upright rows
The aim of this exercise, in which you hold dumbbells, a barbell, or resistance band in both hands and draw them up your body's midline toward the chin, is to work your shoulder muscles. The problem is, you may end up overworking them. "This movement has the potential to compress the nerves in the shoulder area, impinging the shoulder," says Sarah Machacek, NASM-CPT, a Virginia-based personal trainer with two decades of experience. In short, it's a prescription for a rotator cuff injury.

Related: Find More Time to Exercise!

Behind-the-neck lat pull-downs
"Any exercise that brings your spine out of alignment under load is potentially dangerous, and particularly when it's the neck, which is the most fragile section of the spinal column," says Andre Crayton, a personal trainer in Indiana with more than 20 years of experience. "By their very nature, behind-the-neck lat pull-downs require the user to thrust her head and neck forward and break spinal alignment, which can result in a muscle strain, pull, tear, or, even worse, a spinal disk herniation."

Seated leg extensions
This popular machine targets the quadricep muscles at the front of the thighs. However, using this equipment puts your knees in a very compromising position. "Lifting heavy weights in this manner, with all the resistance focused at your ankles, is not what the knee was designed to do," says Machacek. "If you have any kind of knee problem, or use too much resistance during this exercise, you can easily cause injury."

Dumbbell-loaded side bends
Here's another exercise in which what you're actually doing and what you think you're doing don't align. "Not only does it not work your ab muscles, this move places high levels of compression forces on the spine and the soft tissues that act as the spine's shock absorbers," says Michelle Olson, PhD, FACSM, CSCS, a personal trainer and professor of exercise science at Auburn University at Montgomery in Alabama. "It puts you at risk for rupturing a spinal disc."

Related: The Most Effective Exercises at the Gym

Back extensions, especially with added weight
While extension is generally a good thing when it comes to strengthening the core, hyperextension is another story. And with this apparatus, that lower-back overarching (as shown here) is all too possible. "If you have a natural exaggerated curve and extra abdominal fat, you're risking injury of the lower back," says McCormick says. Adding a weight plate ups the danger in the same way, throwing off your balance.

Double-leg raises
There are a number of ways this move, in which you suspend your body and bring the knees or straight legs up toward the chest, can be performed. Most often, it's done hanging from a bar - but it's not the core strengthener you think it is. "Most people overuse their hip flexors in this movement and let their hips fly up with their legs, instead of using their core muscles to keep their hips stable," says Kendra Fitzgerald, ACE-CPT, a personal trainer and yoga instructor in New York City. "This can lead to spasms in the hip flexors from overuse, and even herniated disks, as the weight of the legs creates undue pressure in the vertebrae and the spine flexes and bends with weight."

Tricep dips
Strengthening and toning the back of the arms is something every woman wants, especially since Michelle Obama exercised her right to bare arms. Though, this move, in which you're raising and lowering your body by the strength of your upper body, isn't the best way to accomplish it. "The shoulder is one of the most mobile, yet least stable, joints in the body," says Fitzgerald. "Adding weight - and full body weight at that! - to the joint as you're dipping is an anterior shoulder injury waiting to happen."

Related: 8 Popular Fitness Classes, Explained

Elliptical machine
"Have you ever tried actually walking, er, traveling in a way that is similar to the elliptical machine movement pattern? No? I didn't think so," says Crayton. "And there's a good reason why - it's not exactly natural." The best exercises set you up to be stronger and more efficient in your movements in real life. "Sure, the elliptical burns calories, and it can improve your heart health. But it will not actually improve your fitness level for anything other than using the elliptical machine," he explains. The only reason to use this equipment, Crayton says, is if you're injured and physically cannot walk, run, or climb stairs.

Standing chest fly
The action of opening and closing your arms in front of you works your chest, right? Wrong, if you do this one from a standing position. "Gravity is the enemy here," says McCormick. "You think you're working your chest, but because the weights are pulling down on your arms, you're really just stressing the shoulders' rotator cuffs."

-By Amy Roberts

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