The actor and mum recently embarked on an eight-week fitness challenge with boyfriend Adam Rigby – and the results speak for themselves!

Ada told Who she had noticed “a real shift” in her body following the program, which saw her lose five kilograms – a big change for her petite 1.55m frame.

“Life is really good at the moment. I’m feeling really happy.

“I’ve noticed a real shift in my body. My waist is smaller, my legs and arms have more shape and my booty has lifted – which was one of my goals.”

So proud of the results of my 8 week challenge – check out @whomagazine tomorrow for more pics and details. A ton of hard work, self-discipline around diet and alcohol and belief can get you amazing results regardless of how old you are! A huge thank you to @fitmejones for going above and beyond and Adam for supporting me along the way, and sorry for being grumpy when I was tired and craving carbs #8wkchallenge #whomagazine #obliques #abs #fitfabulous40 #womenshealth #fitness #womensports

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The fitness overhaul saw Ada and Adam train at least five times a week and follow the Keto diet – which meant cutting out fruit, alcohol and carbs and enjoying healthy fats, lean meat and veggies.

“ Do something today that your future will thank you for” ( even if u feel like throwing up after the session ) #8weekchallenge #fitness #fridaymotivation #hiit

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Ada told Who she had always exercised and eaten well. But following a stint of indulgence after her 40th birthday, she hired a personal trainer as she was feeling “tired, lethargic and not very motivated”:

“I wanted to be the best version of myself at 41 and put myself first for a little bit.

“I’m so proud of myself… I’ve got the best body I’ve ever had, but I’ve worked really hard and it wasn’t easy.”

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Ada never thought she’d be “completely happy again” after her son Harrison was stillborn in 2014, with her nine-year-marriage to Chrys Xipolitas ending two years later. She told the mag she was honouring Harrison’s life – as well as her five-year-old song Johnas – by living life to its fullest.

“I’ve made a decision to be happy. And I’m choosing to enjoy my life a lot more.”

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Images: Who Magazine | Ada Nicodemou/Instagram