Protected only by a helmet and a speed suit, American Kyle Wester broke the speed record for skateboarding when he reached 89.41 mph (143.89 kph) ) down a hill at an undisclosed Colorado location on video.

The astounding feat was accomplished in late August but the YouTube video of the amazing run was released Thursday 8 September with the result pending an update by the Guinness World Record organisation. The previous record was 81.17 mph (130.63 kph).

Wester, a 29-year-old professional skateboarder, said he decided to go for a world-record run after a strong trial and good feeling about his latest speed suit and tuck.

The run was made down an empty, sloping mountain road. The Denver native was timed by a crew in the middle of the ride.

"Once I drop in, all my anxieties fade away," he told Transworld Skateboarding. "I become relaxed and focus on keeping my body as still as possible and keeping my tuck tight. You must have complete confidence in your equipment. Catastrophic failure is not an option."

And he's hardly done yet. He plans to break the three-digit miles-per-hour mark, saying: "This is just the beginning," Wester told GrindTV. "I'm hoping in my lifetime I'll be able to get to 100 mph (161 kph) unassisted just by kicking into a hill."

Downhill dream

Wester said breaking the downhill skateboard speed record has been a dream of his for over a decade, but the attempt happened by chance. He was training for an upcoming downhill race in Quebec City, Canada, when he came upon the secret spot and noticed the conditions were perfect.

"It was an 80-degree (26.6C) day, with 35% humidity and the wind blowing in our favor," said Wester. "So I went for it. I did it all in one day. On my third run I beat the existing record by 8.24 mph (13.26 kph). You learn to stay as still and as tight as possible while riding. You learn the right lines to take on a hill. Other than that, it's quite simple."

He admits he grapples with anxiety before starting such a high-risk ride.

"But once I'm moving, it's all about staying as calm, focused and prepared as possible," he told Grind. "Because at that speed, the margin for error is extremely low, and crashing can have horrific consequences."

In 2014, Wester shattered his helmet in a crash, leaving him with a concussion so severe he missed an entire year of competition. Still, he says, there's "nothing in the world" like skateboarding at incredibly high speeds.

"Once you're skating," Wester said, "and you're going that fast standing on a plank of wood and four wheels, you feel free."