AFL WAG Alex Pike, 44, sizzles in a bikini during Melbourne's heatwave

AFL WAG Alex Pike revealed earlier this month she had signed with Melbourne modelling agency Brooklyn MGMT.

And the mother of three, 44, proudly showed off her bikini body on Friday as she enjoyed some downtime over the Christmas holidays.

Alex, who is dating former Collingwood coach Nathan Buckley, drew attention to her athletic figure by posing on a day bed in a skimpy yellow two-piece.

The cosmetic nurse basked in the sun as she placed one hand over her face and held a mug of coffee in the other.

She captioned the post, 'Coffee time,' and noted the temperature was 34°C.

Alex seems to be spending the festive period lazing by the pool, as she'd posted a similar photo of herself lounging around in a patterned bikini on Wednesday.

It comes after the Herald Sun reported Alex had signed with model management titan Brooklyn Edwards - and was already in high demand for jobs.

'My main motivator in business is to show my sons my strength and tenacity, and that hard work is needed to reach your goals,' she said on December 13.

At the time, Ms Edwards confirmed she'd reached out to Alex on Instagram after she was inspired by her positive outlook and business success.

'I reached out to Alex on Instagram - she works, is a mum and manages to do it all,' Ms Edwards said.

'Years ago, 44 was not an age that was appealing [to clients], but I've already had quite a lot of inquiries about her and her profile is growing.'

Alex, who owns two successful cosmetic clinics in Melbourne and Albury, worked as a professional model in her twenties before retraining as a nurse.

She is her own best advertisement thanks to her age-defying appearance, which she has achieved with judicious use of Botox and filler over the years.

Alex also keeps in shape with regular exercise, and walks 10 kilometres per day without fail.

'I'm 44 and I want to get into the best shape of my life. Nothing feels as good as being healthy,' she once said.

The brunette recently told the Ageless by Rescu podcast she plans to live for at least another 76 years.

'I want to live to 120 and that is my goal,' she told host Bahar Etminan last month.

Her tips for extending her life include drinking green juice daily to 'get her body into an alkaline state', guided meditation - and staring at the sun.