Just doing some strength-training exercises means that you’ll get fit, lose weight, and be a better runner, right? Not exactly. By Annie Daly from Prevention

Not every move or machine at the gym is going to make you stronger or fitter. Some are not that helpful at all, no matter how many reps you do. Here are nine moves that simply waste your time, and nine moves you should do instead.

1/ Seated thigh machine (adductor or abductor machines)

Why it’s a waste: It seems like it will help you get rid of the fat on your inner and outer thighs, but it won’t. “Spot reducing” exercises don’t help you lose fat.

What to do instead: Lunges – forwards, backwards and sideways. These exercises tone and strengthen your whole body, including your thighs, says Greg Justice, an exercise physiologist. “Plus, they are functional, which means they train the body for activities performed in everyday life – something the thigh machine does not do.”

2/ Leg extension machine

Why it’s a waste: The stated goal of this machine is to strengthen your quads, but you actually end up just putting a lot of stress on your knees as you straighten your legs from the seated position.

What to do instead: A basic squat or lunge. “They strengthen the quads, hamstrings, and glutes, giving you more bang for your buck,” says Justice.

3/ Crunches

Why it’s a waste: They just aren’t that effective. Research has shown that the crunch is less effective at stimulating muscle fibre than exercises that require the spine to stabilise, like the plank.

What to do instead: Planks. “They activate more muscles in the core than crunches do,” says Travis Barnes, a certified personal trainer. Plus, he adds, they don’t strain your back as crunches can.

4/ Broomstick side bends or rotations

Why it’s a waste: While you may think you’re strengthening your core or burning fat, you’re not. “There’s really no resistance when you put a bar weight behind the neck and start twisting or bending. It’s much better to work against gravity,” says Justice.

What to do instead: A side plank, with or without movement. “Planks work against against gravity, consequently working your muscles more efficiently and effectively.”

5/ Seated chest presses

Why it’s a waste: You’re sitting down, which allows the stronger side of your body to compensate for the weaker side, which means you’ll develop imbalances.

What to do instead: Push-ups. It forces you to develop equal strength, or else you’ll collapse on both sides. Also, the push-up has a plank quality to it, and therefore it stimulates your core even more.

6/ Lying leg curl machine

Why it’s a waste: Lying down to exercise means that your core is not engaged, and you activate the least amount of muscle, says Barnes. “When in real life are you ever lying down curling your legs to your butt for any real purpose?” he says.

What to do instead: Single leg deadlift. “This exercise activates the backside of your body – which includes the lower back, glutes, hamstrings, and calves – while also activating the core with the challenge of instability,” Barnes says. But best of all, “this exercise gives us the strength we need for bending and the balance we need for real life single-leg activities, like climbing stairs, stepping on a curb, or lunging down to pick something up.

7/ Triceps kickbacks

Why it’s a waste: You won’t be able to lift weights that are heavy enough while keeping proper form, to get results. Usually, the upper arm starts to drop toward the floor and you lose the effectiveness.

What to do instead: Skull crushers, i.e. a barbell lying triceps extension. “It still works your triceps but you don’t lose your form,” explains Justice. “The skull crusher position allows your elbows to stay where they belong to get the most of the exercise.”

8/ Standing calf raise machine

Why it’s a waste: The machine loads all of the weight onto your shoulders, which pushes it onto your back before it ever reaches your calves.

What to do instead: Try sprinting. “It’s better than other forms of running running if you want to develop your calves. That’s because it activates more of those fast twitch muscle fibres responsible for strength and growth development, which leads to a more toned body overall,” says Barnes. If sprinting is not for you, try bodyweight calf raises, and if those are too easy, then try them on a single leg.

9/ Leg press machine

Why it’s a waste: People tend to add too much weight, which adds potential for injury. Plus, it’s not that effective: A study compared eight different exercises that target your glutes, and found that the leg press activated the fewest amount of muscles.

What to do instead: Dumbbell squats. You’re still targeting your legs, but it’s more stable and there’s less potential for injury, says Justice.

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