Salma Hayek says she works her muscles 'all day long' without actually exercising.

Image: Salma Hayek — and her brand new fringe. (via Getty).

Usually when a celebrity shares their fitness regimen, it leaves the rest of us mere mortals feeling a little… intimidated. Like when the Victoria’s Secret angels post photos from their gruelling gym workouts, or when we learned Britney Spears walks backwards on a treadmill.

At the other end of the spectrum, you have celebrities like Salma Hayek who claim to stay in shape purely through the power of the mind and being aware of the body. Which is awfully convenient, because she simply doesn’t “have time” to work out.

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“Some people have the discipline to exercise in the morning, and I didn’t develop that,” the actress told People magazine recently. You might not find Hayek slogging it out on the treadmill at 6am, but the 48-year-old reckons her muscles are getting a constant workout, even when she’s at work. (Post continues after gallery.)

“I work with a woman in London who taught me how to hold my body in a way where the muscles are activated all day long. So even when you brush your teeth, you’re working the muscles,” the Frida star says.

“She taught me to tone [my muscles] without clenching them. You relax them and focus on the parts that need to be used, but never with tension.”

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If the concept of ‘activate muscles = Hollywood body’ strikes you as a little too good to be true, you’re not alone — personal trainer and health coach Blake Worrall-Thompson outright rejects Hayak’s claims.

"In terms of activating muscles, when it comes to your core there's an element of learning to engage and activate your inner core muscles, which is important to stabilise the body and also protect the back," he concedes.

"But as a fat-burning tool or as a way of getting in shape, it's just about as outrageous as anything I've heard."

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Although 'activating the muscles' will deliver some benefits for your posture — and certainly for women who are post-natal and wanting to strengthen their inner core and pelvic muscles — Worrall-Thompson says it's going to take a lot more than that to affect the overall look of your body.

"I'm all for people learning how to activate their deep core muscles as a way to help with your posture and a way to activate your abs... but it's not going to make the slightest bit of difference to your body composition or shape," he explains.

If, like Salma Hayek, you're aiming to tone up your muscles, there's a better way to go about it that doesn't even require a gym membership or a Hollywood trainer. Worrall-Thompson recommends addressing your nutrition first, as this plays a major role in how visible your muscles will be, then using particular workout techniques.

"There are also easy body weight exercises you can do — planks, bench dips, push ups, squats, lunges. You can incorporate those into a 20 minute body weight workout. Everyone can find 20 minutes, it's just a case of your priorities," Worrall-Thompson says.

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Hayek's muscle activation claim is one thing, but Worrall-Thompson is more troubled by her assertion that she simply didn't "develop" the ability to exercise in the morning, as if it's some kind of X-Men genetic strain. (Post continues after video.)

"When she's talking about not having the 'discipline' to train in the morning because she didn't 'develop' that — it's not a skill you were born with. It's just a lack of a priority for her when it comes to exercise," he says.

"She talks about working 16-hour days; I know a stack of people who work 16-hour days and still exercise, so I personally don't buy into that. I think it's unfortunately a bunch of excuses, but ones a lot of people relate to because they make the same ones."

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Although celebrities can be a source of interesting fitness ideas — First Lady Michelle Obama hula-hoops, for instance, while Lena Dunham digs acro-yoga — that doesn't mean we should be slavishly following their lead and expecting identical results. (Post continues after gallery.)

What works for one person's body might be completely incompatible with someone else's, and genes play a big role in how our bodies physically look.

There's a very good chance Salma Hayek would look like Salma Hayek regardless of her chosen fitness routine (or lack thereof), so her message could be confusing or even disheartening for someone whose body requires a more sustained exercise regimen.

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"At the end of the day a lot of [celebrities] have really good genes, and it's probably a point where the personal trainer who's looking after them is the person you need to speak to and get advice as to how and why it works, rather than someone like Salma," Worrall-Thompson says.

"For people to get on top of their health and fitness is hard enough without people making these claims, which gets confusing and stressful for everyone."

How do you stay fit?