The Controversial New Fitness Goal You Shouldn't Be Aiming For

First it was the 'thigh gap', celebrating women whose legs don't touch at the top. Next came the 'bikini bridge', where your hips stick out when you're lying on your back, causing a gap beneath your bikini briefs. More recently, we had the 'collarbone challenge', where women demonstrate how many coins they can balance on the bones of their neck. But this summer's new unrealistic fitness craze? The so-called "ab crack".

As seen on Emily Ratajkowski, Stella Maxwell and Bella Hadid, it is typified by the line running down the middle of the abdominals and is seen as the newest way to show off how toned your stomach is on Instagram. But is this latest trend attainable? Or even healthy?

"Anatomically speaking it's the linear alba - the connective tissue holding the abdominals together and protecting your organs and your back. For there to be a huge split down the middle would suggest some kind of bio-mechanical dysfunction," explains Bodyism's James Duigan. "In most cases, it is probably down to genetics so it's not something you can emulate -  it's either there or its not."

Instead, those on the quest for good abs should focus on strengthening their core through high intensity interval training, including exercises that encourage you to stabilise your middle. Read our five ab exercises that are better than crunches here, too.

From: Harper's BAZAAR UK