Davina McCall joked about showing off her “underboob” as she stunned her fans with her incredibly lean physique in a new picture.

The TV star and fitness enthusiast revealed her rippling abs and toned legs while wearing a bikini in a photo posted on Instagram.

The 50-year-old had previously given her 750,000 followers an insight into the preparation for her forthcoming new fitness DVD in a behind-the-scenes video, and showed the fruits of her labour in the snap, proving that she is her own best advertisement.

Along with the image, she wrote: “Cozzie and trainers and a smidgen of underboob (I’m all give)…

“I was a brownie, it was there that I learned ‘be prepared'”

McCall will drop her latest exercise release, Toned In 10, on Boxing Day.

The TV star received a mixed response on social media for her appearance.

Many praised her while others said they were concerned she had lost weight and toned up in the incorrect way.

The former Big Brother host, who celebrated her 50th birthday in October, recently announced that she is splitting from her husband of 17 years, Matthew Robertson.

McCall has two daughters, Holly and Tilly, and a son, Chester, with ex-Pet Rescue presenter Robertson, whom she wed in June 2000.