While Casey went for a black swimsuit, pulling her brunette hair back into a ponytail, her companion opted for colourful striped swimmers for the occasion.
Both Casey and her pal sported unique tattoos – with Casey showing off a snake in the shape of a musical symbol on her thigh.
Her friend, meanwhile, appeared to have a dream catcher tattooed on his left shoulder.
Casey has recently been taking to Instagram to keep fans up to date with her new exercise routing.
The star has been training with fitness expert and celebrity trainer Jono Castano.
“Today was a good session!” Casey shared on Jan. 7.
“I may have had to Uber to the gym with a raging hangover on the account that my Sunday Seshh Cocktails ran a little over time...But, I set an alarm got up and got myself to the Gym and held myself accountable! Thanks @jonocastanoacero For the laughs and the push.”
And Casy was back at the gym on Jan. 17.
“You're an Amazing PT!” she told her trainer.
“We did it and we will keep doing it! You push at the right moments, even when threatened with old mate broom stick (or 10 burpee') Just makes me push harder!!”