SAS Australia’s James Magnussen shows off his muscular build in tiny Speedos as he hits the beach

SAS Australia’s James Magnussen shows off his muscular build in tiny Speedos as he hits the beach – after making his debut on the show

He is one of the 17 celebrities completing a series of gruelling challenges on Seven’s SAS Australia.

And on Thursday, James Magnussen, 29, showed off his muscular build in tiny bright Speedos as he enjoyed a day at the beach, just three days after the show’s premiere.

The former Australian swimmer and Olympic medallist flaunted his bulging biceps as he went for a swim at Sydney’s Bondi Beach.

Muscular build! SAS Australia’s James Magnussen (pictured) showed off his muscular build in tiny Speedos as he hit the beach on Thursday

He wore a fitness tracker around his wrist as he jumped into the water and soaked up the sun.

After going for a dip, James showed off his tattoos as he enjoyed a walk along the sand.

Meanwhile, James is one of 17 celebrities completing military-style challenges in a small town in rural NSW called Bobundara on SAS Australia.

The premiere episode saw the celebrity contestants being punished after Firass Dirani disrespected the Special Forces instructors.

Fancy a dip? The former Australian swimmer and Olympic medallist flaunted his bulging biceps

Surf's up: He was spotted enjoying a swim at Sydney's Bondi Beach

Looking good! The former Australian swimmer and Olympic medallist flaunted his bulging biceps as he enjoyed a swim at Sydney’s Bondi Beach

Splashing around: He wore a fitness tracker around his wrist as he jumped into the water

Splashing around: He wore a fitness tracker around his wrist as he jumped into the water

Unimpressed with the 37-year-old actor’s attitude, the instructors made all the stars submerge themselves in freezing cold water.

But an emotional Roxy Jacenko refused to get into the water, and instead told the staff that she wanted off the show. 

‘I can’t do it. I actually can’t… My leg’s killing me. I can’t do it,’ the 40-year-old publicist told the instructors as she handed over her armband.

Despite being asked if she was ‘100 per cent sure’, Roxy insisted she couldn’t do it, before breaking down in tears.

She only lasted six hours before deciding to quit because it was ‘too demanding’.

Soaking up the sun: After going for a swim, James showed off his tattoos as he enjoyed a walk along the sand

Soaking up the sun: After going for a swim, James showed off his tattoos as he enjoyed a walk along the sand

Fit: James is one of 17 celebrities currently completing gruelling challenges on SAS Australia

Ripped: The celebrities travelled to a small town in rural NSW called Bobundara

SAS Australia: James is one of 17 celebrities currently completing gruelling challenges in a small town in rural NSW called Bobundara 

The season premiere of the Channel Seven show scored an incredible ratings victory over Channel Nine’s The Block.

The show was the most watched entertainment program of the night, launching to 1.194 million viewers nationally.

SAS Australia was also number one in its 7.30pm time slot and trended on Twitter.

SAS Australia also pulled in 834,000 viewers in the five-city metro market, while The Block was watched by 783,000. 

Success: The season premiere of the Channel Seven show scored an incredible ratings victory over Nine's The Block

Success: The season premiere of the Channel Seven show scored an incredible ratings victory over Nine’s The Block

Ratings are in! The show was the most watched entertainment program of the night, launching to 1.194 million viewers nationally

Ratings are in! The show was the most watched entertainment program of the night, launching to 1.194 million viewers nationally

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