The video, posted by athlete Calen Chan, 19, shows him running down the Skyladder Parkour course at Tianman Mountain in China. "It has an average incline of 45 degrees, and is 999 steps long (about 3 football fields)!" he explains in the YouTube description of his video.
A little over three minutes long, the video shows Calen jumping and running through the course. Chances are, you'll be panting just by watching him.
"Obviously this was difficult, and I physically couldn't sprint down the entire path of deadly drops without slowing down, but I did my best," he says on YouTube, adding that he's the only person to do this with a camera in his mouth.
"Great stamina and speed," says one commenter. "I was there two weeks ago when they were building this. Your film doesn't show how steep the steps actually are. Total respect in taking on the course," says another. Click for more trending news