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Fitness forums and comments sections are fit to burst with opinions about the “correct” way to perform an exercise. But is it more than just a matter of personal preference?

In October 2018, physiotherapist and world record-holding powerlifter Stefi Cohen posted an image on Instagram that was always going to prove controversial: that of a man deadlifting with a rounded back.

A post shared by Dr. Stefi Cohen, DPT (@steficohen)

“People get worried when they see someone deadlift with a rounded back,” she wrote – but wrongly so, in Cohen’s opinion. In the post, she meticulously breaks down the complex biomechanics at play before concluding: “I like to think that there’s no bad movement, but rather the unpreparedness for it.” In other words, it’s your strength in a given position that makes it good or bad, not the position itself. (Her post garnered more than 1,200 comments.)

Is good form really just a matter of individual preference?

This idea – that there is no singular, universally “correct” way to perform an exercise – is divisive. On the one hand, there are 50-minute YouTube videos dissecting the minutiae of squat positioning; on the other, lifters who casually throw their weight behind scrappy curls and presses, seemingly without consequence. But is good form really just a matter of individual preference?

“The bigger lifts – deadlift, squat and bench press – tend to be controversial,” says Tarek Shuhaibar, a strength and conditioning coach of nine years, with a keen interest in biomechanics.

Shuhaibar uses the barbell bench press as an example: many people say the bar has to touch your chest for the rep to count. “But your structure plays a role. For instance, if you have a large sternum and short arms, touching the bar to your chest may shift more force onto your anterior deltoids and less onto your pecs,” he explains. “This will make it harder to produce force at the bottom and take the load away from the muscle you’re likely looking to train.”

Shuhaibar is referring to a principle called “anthropometry”, which is the scientific study of the proportions of the human body. “Range of motion, based on our unique structure and mobility, will vary from person to person, and will contribute to the way our lifts look,” he says. “For instance, if I’ve got long legs and short torso, my squat might look different to yours.”

Men with very long legs, to give another example, often struggle with deadlifts, and might benefit from switching to a hex bar. By contrast, the aforementioned Stefi Cohen, who is 5ft tall and deadlifts 4.4 times her bodyweight, favours an unconventional sumo stance, shifting more focus to her quads.

This poses the question: when most moves have so many accepted variations, can you ever tell if a stranger – on Instagram or in the gym – is performing a move “correctly” without context?

Josh Senior is a qualified PT and CrossFit competitor. In 2010, a 35ft fall resulted in him sustaining life-altering injuries, along with the amputation of his foot and ankle. Senior also has a kink in his lumbar spine, which means he can’t adhere to one of the most commonly cited training instructions: “maintain a neutral spine”.

A post shared by Jason and Lauren Pak (@jasonandlaurenpak)

“I’ve had people come over to me while I’ve been doing barbell work and we’ve had a good conversation about why my set up might not look the same as theirs.” But, he says, he’s also had interactions with “some very arrogant people”, intent on discouraging him from performing his workouts in a manner they deemed to be flawed.

Senior’s situation might be particular to him, but he believes there are lessons for all lifters here: “Develop good habits and work on your mobility,” he says – but don’t let excessive fear prevent you from trying unfamiliar movements: “Our bodies are designed to move in a multitude of directions and handle different forces. There is a lot to be said for making sure your body is strong unconventional positions, because real life will throw you into those positions.” After all, he points out, picking up a wriggling five-year-old kid is more challenging than cleaning a 50kg barbell.

While it’s true that best form is influenced by a multitude of factors – individual strengths and weaknesses, body shape and size, the muscle groups being targeted – there is also a benefit to having simplified, agreed-upon guides for performing certain exercises, particularly for beginners. Shuhaibar likens it to learning a new language: “The further you’re able to standardise it, the quicker you pick it up.”

Memorising simple cues when first mastering a new movement will provide you with a foundation on which you can build as you become more experienced, playing with new variations.

Taofique Folarin, a PT and fitness instructor of 10 years, points out that any idea of the “correct” way to execute a move should always be grounded in two core principles: “to maximise effectiveness and to minimise injury risk”. He likens training with poor form to riding a bike up a hill in a high gear: “You may eventually get to the top, but it will be harder and less energy efficient.”

If your only goal is to burn calories, this loss of energy-efficiency might not matter so much – again, so long as you’re not at risk of hurting yourself.

When coaching clients, Folarin likes to emphasise the “why” behind the form tips, not just the “how”. “Why should the move be executed in this certain way, why is it more suitable for your body or your goals – then it becomes education through movement.”

"Form correction on social media can quickly turn into a game of one-upmanship"

But while advising clients is a trainer’s job, form correction on social media – and in the gym IRL – can quickly turn into a game of one-upmanship. If you’re genuinely worried that a person is at risk of hurting themselves due to the way in which they are performing a given exercise, Folarin advises trying to relate to them, rather than lecture them. “If I see someone executing a move that I also used to do incorrectly, I can offer advice through [sharing] my own experience. It’s about empowering the individual to make an informed choice. Respect is key.”

Hendrick Famutimi, a PT and former GB powerlifter, can see an upside to the increased debate around what “proper form” looks like. With posture and positioning now more of a social-media talking point, “a lot more people are trying to wise up by watching video tutorials posted by professional coaches and athletes,” he says. Although he advises choosing your tutor carefully: “Bro-science will always be around. The moment you have abs, you can say the sky is pink and people will believe you because they want abs, too. Just because you work out, doesn’t necessarily mean that you understand the biomechanics of a squat.”

Ultimately, the best results can be found in the middle ground between rigid dogma and wild experimentation. Move mindfully. Pay attention to aches and niggles. Don’t let your ego compromise your safety. Consult a professional if you find yourself in doubt. And the cardinal rule: don’t bother arguing with strangers on the internet.