Fans quickly flocked to the photo.
"Someone grab a fire extinguisher because you look hot," one wrote.
Another added, "This is insane."
"Holy crap your bod is awesome. Lots of hard work there, well done you," a third captioned.
Other comments included “body goals” and simply “wow”.
The 25-year-old who won last year’s season of The Block with partner Josh Barker, has gained attention working as a model. Most recently, Elyse landed the role as the face of Aussie swimwear label Seafolly.
“I think it [Seafolly] has put me on another level,” Knowles told Sunday Confidential.
“It has made my brand even bigger and better than it was.
“Seafolly is such an iconic Australian swimwear brand that is recognised globally, so it is so nice to have my name recognised alongside these other faces of Seafolly.”