1. LEG-CURL MACHINE
Why it's useless: Your hamstrings perform two movements: knee flexion and hip extension. The leg curl machine works only knee flexion, which limits the benefits, says Muelrath.
What to do instead: Choose a machine or movement that works both hamstring functions at once, such as the fitness ball hip raise and curl.
To do: Lie on your back with legs straight, heels on the ball. Raise your hips by pressing your heels into the ball until your legs are straight. Keep your hips raised as you roll the ball in toward you by bending your knees. Continue rolling out and back towards you for 10 to 12 reps.
2. PULLEY MACHINE FOR SIDE BENDS
Why it's useless: Endless side crunches on this pulley machine do nothing for reducing "love handles," as many people believe.
What to do instead: Reducing excess fat around the midsection requires a good sound nutrition plan along with effective moves such as side planks.
To do: Lie on your side with your forearm on the mat under your shoulder, and stack your upper leg directly on top of the lower leg. Rise upward by straightening your body. Hold 20 to 60 seconds, then switch sides. Do three reps on each side.
3. BUTT BLASTER
Why it's useless: This donkey kick machine is an unnatural movement, says Tom Holland, MS, CSCS, a Connecticut based personal trainer and author of Beat the Gym. "The idea is to spot reduce the glutes, which isn't going to happen."
What to do instead: A better choice are squats, which use your own body weight. "Squats get the glutes as well as the hamstrings and are a much more productive exercise," says Holland
To do: Stand with feet slightly wider than shoulder-width apart, arms straight in front of you, parallel to the ground, or clasped behind your head. Keep head up as you bend at the knees and hips and lower into a squat position until thighs are parallel to the ground (or as low as you can without lifting your heels). Pause and slowly raise back up to starting position. Repeat for two to three sets of 12 to 15 reps.
More from Prevention: 4 Amazing Butt Moves
4. OVERHEAD SHOULDER PRESS
Why it's useless: The shoulder joint is easily prone to injury, especially in this unstable overhead move, says Muelrath.
What to do instead: Challenge shoulder muscles with less injury risk by doing lateral dumbbell raises.
To do: Grasp dumbbells and stand with palms together in front of thighs, elbows slightly bent. Raise arms up and out to the sides until elbows are at shoulder height; pause and return to starting position. Repeat 10 to 12 times.
5. ROMAN CHAIR SIT-UPS
Why it's useless: This move targets the hip flexors, which are not involved in abdominal development, says Muelrath. "It also creates a lot of stress on the spine."
What to do instead: Target abdominal muscles by working to stabilize your body position with planks.
To do: Lie facedown on the floor and prop yourself up on your forearms; extend your legs behind you until your body is parallel to the floor. Engage your core by drawing your stomach back and up towards your spine and hold; start with 10 seconds and work your way up to 60 seconds for two to three reps. (See the move in motion with this quick video demonstration.)
6. ROTARY TORSO
Why it's useless: The twisting motion of this machine is touted as a way to banish a "muffin top." "This machine doesn't activate the muscles in the correct way, and the potential for injury risk is high," says
What to do instead: Try a standing cable rotation using rubber exercise tubing.
To do: Stand in a slightly wider than shoulder-width stance and grasp the handles of the pulley or tubing with both hands, your side toward the tubing attachment point, arms straight in front of you. Tighten your abdominal muscles and rotate your upper torso as you pull the tubing away from its origin. Slowly return to starting position. Repeat 10 times, then switch sides.
7. SMITH MACHINE
Why it's useless: The Smith machine, a multi-purpose machine using a bar attached to a sliding sled, is used for upright rows. But pulling the bar up and under the chin in this way compresses nerves in the shoulder area and can lead to inflammation, says Muelrath.
What to do instead: Strengthen the same muscles without the injury risk with dumbbell front raises.
To do: Hold onto dumbbells and stand with arms straight, palms facing your thighs. Alternately raise one dumbbell to shoulder height; pause and lower. Repeat with other arm. Perform 10 to 12 reps each arm.
8. LEG EXTENSION MACHINE
Why it's useless: Sitting and extending legs out to a horizontal position is simply not functional, says
What to do instead: Choose an exercise that targets many leg muscles at once, such as lunges.
To do: Stand with dumbbells or your hands on your hips. Step forward with your left foot, landing on the heel then forefoot and lowering yourself towards the floor. Both knees should be bent at a 45-degree angle. Return to original position by extending your left knee and hip. Alternate sides for 10 to 15 reps each leg. (Sore knees? Try these gentle knee-saving exercises.)
9. INNER AND OUTER THIGH MACHINE
Why it's useless: This machine appears to work the inner and outer thigh muscles, but you won't get out of it what you want, says
What to do instead: Aside from losing weight to reduce body fat,
10. AB CRUNCH MACHINE
Why it's useless: The ab machine can be awkward at best, and injurious at worst, says
What to do instead: Planks offer a much more natural alternative to build strength, says
(Source: Yahoo Shine)