10 Exercises You Can Skip — and What to Do Instead, According to Trainers

Take a look around your gym: You'll probably see some fellow gym-goers hammering out these exercises, but that doesn't necessarily mean you should, too. These common gym exercises can be ineffective (aka there are faster ways to get the results you're after) or sometimes even put you at risk for injury. Long story short, these exercises and machines aren't doing your body any favors. Learn what trainers say you should be doing instead.

Smith Machine Squats

Squatting on a Smith machine might look like a safe alternative to the squat rack. The reality isn't so clear. When you lower into a squat using a Smith machine, your back stays straight and almost perfectly perpendicular to the ground, which compresses and stresses the vertebrae, says Lou Schuler, C.S.C.S., co-author of The New Rules of Lifting Supercharged. Also, since using the Smith machine requires leaning back into the bar, you overly stress your knees, never fully contract your glutes or hamstrings, and don't train your core.

Try instead: Weighted Squats

Save yourself the risk and learn how to do a barbell squat without the machine. Both bodyweight and weighted squats (e.g., goblet, barbell, and dumbbell variations) train your entire lower body functionally, effectively, and without overstressing your joints, Schuler says. Plus, since you're not relying on the stability of a machine, these exercises also work your core.

Machine Leg Extensions

How often do you just sit around and kick out your legs? Probably not often — if ever. So why do so in the gym? "There's no functional benefit to leg extensions," says strength coach and personal trainer Mike Donavanik, C.S.C.S., C.P.T. (Functional exercises use your body's natural movement in ways that apply to real-world motions.) Plus, your knees aren't designed to carry weight from that angle, which could cause injury. While your injury risk is low if you have otherwise healthy knees, why take the risk if the exercise isn't even functional to begin with?

Try instead: Squats, Deadlifts, Step-Ups, and Lunges

All of these moves are great for training the quads. Not to mention, they simultaneously strengthen your glutes, hamstrings, and smaller stabilizing muscles. Since these are all functional exercises, tapping your body's natural movement patterns, your knees are designed to take their weight, he says.

Ab Machines

Sure, ab machines are a lot more comfortable than arms-behind-the-head sit-ups, but they can make it awkward to activate your core muscles correctly, says Jessica Fox, founder of Alchemy Nutrition & Wellness, and a certified Starting Strength coach, formerly at CrossFit South Brooklyn.

Try Instead: Planks

Most people can just do full sit-ups. Even better? Drop into a plank: It's more effective for toning your abdominals than an assisted crunch (or any machine), and is typically safe for people who can't do sit-ups because of neck pain. (Up your ab game with this powered-up plank workout that HIITs your core hard.)

Behind-the-Head Lat Pull-Downs

When performing lat pulldowns, the bar should always stay in front of your body. As in, always. "Otherwise it's a shoulder injury waiting to happen," says women's strength expert Holly Perkins, C.S.C.S. Pulling the bar down and behind your head and neck places extreme stress and strain on the front of the shoulder joint.

Try instead: Wide-Grip Lat Pull-Downs (in front)

Pulldowns are still your traps' main move — just focus on aiming the bar toward your collarbone. You don't need to bring the bar all the way to your chest, but you should move in that direction, Perkins says.

The Elliptical

There's nothing "wrong" with the elliptical — in fact, there is a slew of benefits for beginners and those recovering from an injury, but this common cardio machine leaves a lot of room for user error. Since you move through a relatively small range of motion, it's so easy to slack on form and muscle activation on the elliptical, says Christian Fox, a certified Starting Strength coach formerly at CrossFit South Brooklyn. (Read more: Which Is Better: The Treadmill, Elliptical, or Bike?)

Try instead: Rowing Machine

The rowing machine is a better choice to get your heart rate up. "Rowing incorporates a lot of muscle mass into the movement, and with a little technique can provide a wallop of a workout," Christian Fox says. Skeptical? Attempt a 250-meter sprint at max effort, and you'll never want to step on the elliptical again. (Not sure where to start? Here's how to use a rowing machine for a better cardio workout.)

Abductor/Adductor Machines

Like many machines in the gym, these target one specific area of the body — which is simply an inefficient way to work out when there are so many moves that will work multiple muscles at once, Jessica Fox says.

Try instead: Squats

Skip the machines and drop down into a squat. A proper squat recruits more muscles (including the ad/abductors) and is a functional movement, meaning it'll better prepare your muscles for real-life challenges, like walking up the stairs and picking things up. (Want more multi-muscle moves? Check out these functional fitness exercises.)

Triceps Dips

It's meant to train your triceps, but it can easily end up overloading the small muscles that make up your shoulder's rotator cuff. "It's a risk to lift your body weight when your upper arms are behind your torso," Schuler says. Damage those muscles and even everyday tasks — like washing your hair — can become painful.

Try instead: Cable Pushdowns, Triceps Push-Ups, and Close-Grip Bench Presses

Define your triceps while keeping your arms in front of your body with any of these moves, Schuler suggests.

Superman

"The amount of force and compression that gets placed on the vertebrae of the low back is unreal," Donavanik says. "Yes, you're working your spinal erectors and many stabilizing muscles throughout the back and core, but you're placing a ton of force and stress on a very sensitive and specific area in the body."

Try instead: Bird-Dog

Get on all fours with the bird-dog exercise, advises Donavanik. The yoga staple strengthens the same muscles while placing less force on the spine. Good mornings, deadlifts, and floor bridges are also great alternatives, he says.

Very Light Dumbbells

Light weights have their place in barre or spin class, but if you're lifting too light you could be missing out on some serious sculpting. (BTW, here are five reasons why lifting heavy weights won't make you bulk up.) Yes, you will want to start out light if you've never lifted. But over time you must lift progressively heavier weights to gain strength and definition, Jessica Fox explains.

Try instead: 5+ pounds

How heavy should you go? Depending on the exercise, the weights should be heavy enough that the last two reps of each set are significantly challenging. (Need more convincing? Read these 11 major health and fitness benefits of lifting weights.)

Anything That Hurts

There's something to be said for pushing through muscle fatigue and discomfort. But when discomfort turns into pain, the opposite is true. "Pain is your body's way of saying, 'Stop! If you keep doing this, I'm going to tear, break, or strain,'" Perkins says. What's the difference, exactly? While discomfort feels like a dull or burning ache in the muscles, acute pain tends to be sharp and sudden, and most often strikes near a joint, she says.

Try instead: There's an alternative move for every exercise out there whether you're modifying for an injury, for pregnancy, or just because you want to break out of a workout rut. Be sure to ask your trainer for a move that works for you.