Millie Mackintosh is so small you could probably roll her up and put her in a cardboard tube, much like the That That posters you used to buy at Woolworths. But that hasn't stopped her from getting on it at the gym this January. So on it, in fact, that we feel knackered just scrolling through her Instagram pics.
The former Made In Chelsea star, who married Professor Green last summer, has been busy since leaving the Reality show. Busy getting herself into even better shape, that is.
She posted a video of herself doing "the plank of death" - a gruelling workout involving getting in and out of the plank as quickly as possible while a personal trainer yells at you.
She's also been uploading photos of her post-exercise body, including close-ups of her thigh gap, which tbh we thought was just an internet thing like Throwback Thursday or Kim Kardashian.
Despite her tiny frame, Millie has insisted in the past that she doesn't suffer from an eating disorder - and even used to be bullied in school for being slim.
"I was bullied to the point where I wouldn't go to school," she told Fabulous magazine last year.
"I was skinny, had glasses and wore braces to realign my jaw. I had full-on yellow hair after a home hair dye job and had really bad acne all over my forehead."
But there's no denying Millie's working hard to tone up, as she's been tweeting about her exercise regime since Christmas.
Check out the pictures of Millie's body transformation in the gallery below.