Amanda Holden showcased her age-defying physique on Instagram today as she enjoys time at a Juice Master Retreat in Portugal to help maintain her enviable shape.

The 46-year-old showed off the fruits of her labour as she clung onto the end of European summer, taking a dip in a chilly lake. She wore a stylish brown bikini by designer brand Heidi Klein with an oversized straw hat and sunglasses to protect her youthful complexion.

Holden, who has been a vegetarian since she was 13, stunned her 587K followers with her svelte and toned figure that could easily belong to a woman half her age. She captioned the snap: "First toe in. "#chilly#Swimming this #lake this morning @juicemasterretreats #friends #retreat#juice #health #exercise".

Her fans were gobsmacked by her appearance, with one person commenting: "Still have fabulous figure" as another put: "Wow looking beautiful "

A third added: "Les Dennis must be crying right about now bc the survey says: "HOT!"....anything else and 'I'll give you the money me'self"'.

The TV personality may have given away the secret to her eternally youthful appearance by sharing a snap of a very green smoothie as she lapped up the sunshine with pals.

Holden – who is a judge on ITV's Britain's Got Talent – married family entertainer Dennis in June 1995, but the pair split after her affair with Bob the Builder voice actor Neil Morrissey was exposed.

She married record producer Chris Hughes at Babington House in 2006 and the pair have two children together.

Enjoying the #sunshine #friendship and #cleanse of both #body but much more importantly #mind on this amazing trip @juicemasterretreats #portugal 🍏😘❤️ @officialnicstep @theangelagriffin

A post shared by Amanda Holden (@noholdenback) on

The secrets to Holden's amazing figure throughout her career was revealed last year, when it was claimed she abides by the Viking Method. Holden was working out with Icelandic personal trainer Svava Sigbertsdottir, founder of the hardcore discipline, who she credited her strong and lean figure to.

Holden trains and eats like the Scandinavian warriors when she's practising the very special lifestyle, and goes through endless rounds of squat thrusts, boxing, bunny hops, jumps and crawls during the gruelling workouts.

Her trainer previously said: "We focus on core power exercises and have made her core very strong.

"Amanda is an absolute firecracker. She doesn't shy away from any exercise, no matter how exhausting it is. She never gives up, that is her secret."