From lifting too much weight to poor technique, an exercise performed incorrectly can mean you're not getting the benefits you're looking for, and can even cause pain and injury.
According to a poll of 942 fitness professionals by sports retailer Sweatband.com, top of the list is the bicep curl, followed by stomach crunches and the chest press.
Physiotherapist Nick Sinfield, a back pain specialist, describes the most common exercises done incorrectly and explains how to do them safely and efficiently.
"To maximise the benefits of these exercises, aim to perform them in a slow and controlled manner, going through the full range of motion and lifting within your comfort zone," says Sinfield.
Target: front of the upper arm
The most commonly reported error was people simply trying to lift too much weight, which engages the shoulders and reduces the effort on the biceps.
"If the weight is too heavy, you'll be working the shoulders and not properly targeting your biceps," says Sinfield. "Your shoulders will hunch forward instead of staying back as you lift the weight, which can cause injury."
He says leaning backwards when lifting too much weight puts a lot of pressure on the lower back, which can also lead to injury.
"To maximise the efficiency of the bicep curl, lift within your comfort zone, keep your back still and straight, and focus the effort on the biceps only. If you can't do the exercise with the correct technique, it means the weight may be too heavy."
How to do a bicep curl correctly:
- Stand tall with your shoulder blades back and down, and contract your abs.
- Keep your back, elbows and shoulders still.
- Curl your arms up until they're in front of your shoulders.
Common mistakes that reduce the effectiveness of a stomach crunch are tucking the chin into your chest, jerking up into a crunch, raising yourself too high off the floor, and not keeping your abs contracted throughout the exercise.
"All the work should come from the abs, not the neck," says Sinfield. "If done properly, you should not feel any strain in the neck."
While crunches improve posture, stabilise the core muscles and contribute to a healthy back, doing hundreds of them is probably a waste of time. "No matter how many crunches you do, you won't get a six-pack if your abs are hidden under layers of fat," says Sinfield.
How to do a crunch correctly:
- Curl up until your shoulders are about three inches off the floor.
- Don't tuck your neck into your chest as you rise – imagine a tennis ball between your chin and chest.
- Contract your abs throughout the exercise.
- Don't jerk your head off the floor.
Target: chest, shoulders and triceps
Failing to keep the shoulders back and down was the most frequently reported mistake with the chest press.
"To perform a chest press correctly and reduce your risk of shoulder injury, you should keep your shoulders back and down throughout the entire movement," says Sinfield.
The common mistake is to round the shoulders forward and upward as you press, which not only reduces the work on the chest, but also puts the shoulders in a vulnerable position.
Sinfield says there is also a tendency to recruit the legs and buttocks to help with the effort. "Don't contort your body in an effort to lift the weight – if you can't maintain proper form, you're lifting too much," he says.
How to do a chest press correctly:
- Keep your shoulders back and down.
- Contract your abs throughout the exercise and keep your neck relaxed.
- Maintain a natural arch in your lower back – don't let it arch too much.
- Don't lock your elbows when raising the weight.
Target: thighs, buttocks and lower back
Putting too much pressure on the lower back and not enough leg work were the most commonly observed mistakes with the squat lift.
"Don't round your back," says Sinfield. "Your spine needs to remain in a neutral position throughout the exercise. All the effort should come from the leg muscles."
To keep your back in the correct position, keep your back straight and contract your core muscles and buttocks. As you lower yourself, imagine sitting back on a chair, and do not let your knees lean over your toes.
"Practice correct technique using a weightlifting bar or squat rack without weights in front of a mirror," says Sinfield. "When you come to using weights, it's advisable to have someone experienced watch you."
How to do a squat lift correctly:
- Feet should be shoulder-width apart and slightly turned out.
- Keep your shoulders back and down, and your chest pushed out.
- Shoulders should remain directly above the hips.
- Lower yourself as if you were sitting back on a chair.
- Keep your weight on your heels, not the toes, throughout the movement.
- Don't let your knees lean over your toes as you lower yourself.
Target: back and bicep muscles
Pulling the bar down behind the neck was the most commonly reported issue with the lat pulldown.
"When people perform the lat pulldown behind the neck, they tend to bend their head forward as they bring down the bar, which puts strain on the neck and shoulders," says Sinfield. "It's safer to bring the bar down in front of your body."
To perform the lat pulldown correctly, lean a little bit back from your hips, bring the shoulder blades back and down, and pull the bar down towards your chest.
"Keep your spine in a neutral position and engage your core muscles throughout the exercise to protect your back," says Sinfield. "If you find you're arching your back as you pull down, it probably means you're lifting too much."
How to do a lat pulldown correctly:
- Keep your shoulders back and down.
- Lean a little bit back from your hips.
- Pull the bar down towards your chest.
- Contract your core muscles.
- Don't arch your back.
Target: stomach and back muscles
The plank is an effective exercise for developing your core strength around the spine, but bad form can hurt your shoulders and back.
"The common mistake here is sagging at the hips or raising the bottom too high," says Sinfield. Raised buttocks or collapsing back are a sign of a weak core. "Either way, you are reducing the effectiveness of the exercise," says Sinfield.
A collapsing back also puts too much pressure on your lower back, which can lead to back pain. "To get the best results, always maintain perfect form," says Sinfield. "If you lose form during the exercise, it means your muscles are tiring. Stop and have a rest. You can build up how long you do the plank gradually."
How to do the plank correctly:
- Keep your legs straight and hips raised to create a straight and rigid line from head to toe.
- Your shoulders should be directly above your elbows.
- Keep your abs contracted during the exercise.
- Don't allow your lower back to sink.
- Look down at the floor.
Bent over row
Target: back muscles and biceps
A hunched back was the most common error reported among people doing bent over rows.
"Having a curved spine when doing this exercise puts a lot of pressure on your back and can cause injury," says Sinfield. "You should maintain a neutral spine throughout the exercise."
To correct this mistake, pull in your core muscles, look ahead of you and keep the chest high. Pull the bar up towards the waist, not the chest. "Pinch your shoulder blades together as you pull the bar towards your waist," says Sinfield.
To get the full benefits from this move, pull the bar all the way up to the waist just above the belly button, keeping your elbows tucked in. Lower the bar by straightening the arms completely.
How to do a bent over row correctly:
- Bend forward at the waist, keeping your chest high.
- Bend your knees slightly and keep your back straight.
- Keep your shoulders back and down.
- Pull the bar towards your waist, just above the belly button.
Target: thighs and buttocks
Starting with your knees bent right into your chest was the most common mistake with the leg press.
"This starting position is often referred to as 'going too deep' and it puts a lot of pressure on your lower back," says Sinfield.
In the starting position, your legs should not be bent more than 90 degrees. When you straighten the legs, push through the heels, not the toes, to avoid straining the knees. Don't lock your knees when you straighten the legs.
"As you straighten your legs, maintain a neutral spine and keep your neck relaxed," says Sinfield. "Don't flatten your lower back against your support."
How to do a leg press correctly:
- Start with your knees bent at no more than 90 degrees.
- Straighten your legs by pushing through the heels, not the toes.
- Don't lock your knees at the top of the move.
- Maintain your lower back's natural curve – don't flatten your lower back against the support.
- Keep your neck relaxed and your head pressed against the support.
Target: abs, hip flexors
The most common mistake seen with leg lifts is allowing the lower back to arch too much. This strains the back and makes the move much less effective as an abdominal exercise.
"If you don't keep your back muscles and abs contracted, you're only working your hip flexors," says Sinfield. "If you're just starting out with this exercise, focus on doing a few while focusing on proper technique," he says. "You can increase the number of repetitions gradually."
To get the most out of this exercise, Sinfield advises lowering and lifting the legs slowly, while keeping the abs under constant contraction and without letting your heels touch the ground. "When you feel your lower back starting to arch, it's time to stop."
How to do leg lifts correctly:
- Don't flatten your lower back against the surface – maintain its natural curve.
- Keep your head and shoulders pressed against the floor.
- Your neck should be relaxed.
- Keep your abs contracted throughout the exercise.
Target: thighs and buttocks
Done properly, lunges are a great exercise to improve your core strength, but all too often people are risking injury because of poor technique.
One of the most commonly reported errors with lunges is stepping into the lunge and allowing the front knee to lean over the toes. "This puts a lot of stress on the knee," says Sinfield.
Other common mistakes include leaning the upper body forward or to one side instead of staying upright, and looking down, which can strain the neck.
"Using improper form not only has less benefit for the thighs and buttocks, but it can result in injury, especially to the knees and back," says Sinfield.
How to do a lunge correctly:
- Step forward with one leg, lowering your hips until both knees are bent at about 90 degrees.
- Don't let your front knee lean over the toes as you lunge.
- Keep your upper body upright at all times and look straight ahead.