Today is Chris Hemsworth 40th birthday, and the celebrations began with a morning surf in Byron Bay.

Joined by his brother Liam, 33, and surfer mate Owen Wright, the Australian superstar shared a laugh with his companions in the carpark before heading down to the beach.

The Marvel star’s friend Owen appeared to gift him with a copy of his autobiography to make the special occasion.

The boys then stripped down and changed into their wetsuits to head into the surf for a workout.

The Thor star sported some scruff on his face and a sun-kissed tan as he fiddled with his surfboard in the carpark.

Chris showed off his fit physique as he carried his surfboard under his sculpted arm down to the water.

He strolled the beachside with his wetsuit half off, baring his thick biceps and toned abs.

Not to be outdone, brother Liam also bared his chest as he changed into his surfing gear.

The Hemsworths and their friend enjoyed an invigorating surf to help make the start of Chris’ fortieth year a memorable one.

The A-lister stays in phenomenal shape by sticking to a strict workout regime and maintaining a high-calorie diet.

Hemsworth kicks it into high gear before a film, as his longtime stunt double, Bobby Holland Hanton, 37, recently attested to his intense physical preparation prior to taking on a role.

Chris pushed Bobby to the limit on the last film in the Thor franchise, giving his stunt double just eight weeks to bulk up for Thor: Love and Thunder.

In a recent interview with Ice36, Hanton described the grueling demands placed upon him, saying he told the star, ‘You’ve got to be kidding!’

Bobby had to pack on nearly 22 pounds of muscle and consume 4000 calories a day so he would transform into a convincing Thor.

‘I was eating up to 10 meals a day, two of those would be protein shakes,’ Bobby shared with Ice 36.

‘We [he and Chris] were training twice a day and I never thought in my life that I would be sick of food and not wanting to eat food, because I love food.’

But the film industry veteran, who has worked with the Aussie-born superstar for 15 years, says the training regime was a real test.

‘I hated it. In the end, I was trying to give away food that I was supposed to eat because I just didn’t want to eat it, it would almost make you feel sick because you were never, ever hungry’ he said.

Speaking about his preparation for Thor: Love & Thunder, Hemsworth said in the Marvel documentary Assembled that ‘it was just exhausting.’

Calling his transformation ‘particularly hard,’ he added, ‘I don’t know, maybe I’m getting old, but things just started to hurt more.’

In an interview with USA Today to promote the film last year, Chris revealed his lifestyle during Covid lockdown: ‘It was train, eat, train, eat. Nothing else to do. Then I turned up for the film bigger than I’ve ever been.’

But his wife Elsa Pataky wasn’t into the extra muscle, as Chris said she called it ‘too much,’ echoing the couple’s female friends: ‘There are a lot of my male friends who are like, ‘Yeah!’ but a lot of female friends and family are like, “Yuck.”‘