Jessica Alba reveals she wore a double corset for THREE months after giving birth, expert warns 'not best practice' for new mums

Jessica Alba boasts one of the most enviable bikini bodies in Tinseltown, but it seems her toned physique isn't the work of another celebrity diet.

The mother-of-two has opened up about how she got back her toned tummy after childbirth, revealing she wore two girdles after the arrival of second daughter Haven, in 2011.

In a new interview, the 31-year-old said she wore a 'double corset' after the birth - admitting it was "brutal."

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She told net-a-porter magazine: "It was brutal. It's not for everyone. I wore a double corset day and night for three months."

But while Jessica said it was tough experience, she's glad she went through with it.

"It was sweaty, but worth it," she added.

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The actress turned entrepreneur's comments have today sparked a debate over the effects wearing restrictive clothing clothing can have on the body after the trauma of childbirth.

Alison Edwards, Senior Lecturer in Midwifery at Birmingham City University, said Jessica's method of getting back into shape isn't 'best practice' for new mums.

She told us: "Her motive is probably because she's a celebrity and wants a trim figure.

"[But] it's not something that is good practice. Thinking logically, your stomach muscles have to rebuild themselves after being stretched with a baby.

"Wearing a corset could stop muscles working for themselves."

Alison admitted it's not the first time she's heard of new mums wearing tight clothing to help get back into their pre-baby clothing.

"There's talk about doing it with leggings too," she said.

"Yes [like the corset] they will make you look good, but it won't do much for your muscle tone."

She explained that instead of relying on tight clothing to tone your tummy, it's actually more important to get your muscles working - albeit gently - to help regain that muscle tone.

"The best way to lose weight after having a baby, is to breastfeed," she explained.

"You lose 500 calories per feed. But whether you choose to breastfeed or not, having a baby will help you lose weight anyway as you're always on the go."

Of course, as Jessica Alba's comments prove, many mums don't want to feel they have to give up exercise altogether just because they're pregnant.

And Alison says that doesn't have to be the case, but expectant and new mums should simply opt for gentler forms of being active.

She explained: "After you give birth, you still have high levels of hormones in your body for about six to eight weeks.

"You have one called Relaxin and Progesterone, both of which actually relax muscle tone.

"So you can do mild exercise when you're expecting and while these hormones are still around in your body."

She continued: "You still need to get in the practice of exercising and actually, your body is designed to get itself fit after you give birth.

"You can put groundwork in when you're pregnant, being sensible with your diet etc.

"You body actually one needs about 200 extra calories a day and you should choose healthy foods."

Alison said the issue mums face nowadays is the concept they have to look like film stars after a baby.

But actually that isn't the case and she advises women are "real about it."

"You have enough to deal with recovering from birth," she insisted.

"Eat sensibly, breastfeed if it's your choice and do gentle exercise. Walking is just as good an exercise, especially when you're pushing a buggy - that's using your stomach muscles."

 Tell us what you think of Jessica Alba's corset comments over on Twitter, now.