Londoner Sam Holness will break new ground when he becomes the first openly autistic triathlete to compete at the Ironman World Championship in Hawaii.

The 29-year-old completed his first full Ironman of a 2.4-mile swim, 112-mile cycle and marathon at the European Championship in Frankfurt earlier this year having previously raced marathons and shorter distance triathlons.

Now he is targeting an 11-hour finish at arguably the sport’s most famous event, which takes place over the next three days in Kona.

“It’s the biggest race of my life,” Holness told the PA news agency. “It’s really exciting. I’ve trained so hard for this.”

Having started swimming aged three, Holness tried other sports including archery, judo and running before putting all his energy into triathlon, with a training schedule of 24 hours a week.

His coach is his father, Tony, who was determined to help Sam have a fulfilling life.

“Part of the autism trait is to do repetitive things,” said Tony. “As a boy he would make a long line of trains, for example.

Sam Holness (centre) with his parents Tony and Marilyn
Sam Holness (centre) with his parents Tony and Marilyn (Sportograf/handout)

“What we’ve done is adapt that repetitive behaviour. Being an athlete is about repeating the right thing over and over again until you perfect it.

“We quickly learned that, if he’s repeating things and learning, which is probably how most of us learn anyway, then we could channel that for him to have a really productive life. Adults in the UK with autism have a life expectancy of 54 years and we just wanted to get him healthier.”

It is very much a family affair, with Sam and Tony, along with Sam’s mother Marilyn, eager to show what is possible.

“My mum and dad inspire me,” said Sam. “They never give up on me, they always encourage me.”

Sam’s long-term goal is to become the first black professional triathlete with autism and encourage other people like him to believe the sport can be for them.

Tony has been heartened by the welcome Sam has received in triathlon, saying: “Although it’s not a very diverse sport, they’ve been extremely positive. We’ve met athletes with Down Syndrome, para athletes.

“There are a lot of men, not a lot of black and Asian athletes. We want to help grow the sport. We thought if we can get Sam to that sort of iconic status then others will join in.

“Everyone says, ‘I can’t be what I can’t see,’ but I don’t believe that. We’re actually saying we can be what we can’t see because there’s never been anyone like Sam before.

“We’re a very positive family. He’s our only son and this is his life. He’s enjoying it and we get to travel round the world and watch him.

“We never dreamed of this, we could not imagine it. Even for someone neurotypical you wouldn’t imagine this for your child. I say to everybody he’s my hero.

“As long as he’s healthy, we think he’s going to do great things. He’s already doing great things. We’re very proud of him.”