Josh Levin’s journey to season eight of “American Ninja Warrior” began when he was just 4 years old at Great America. The young Sunnyvale native approached a rock climbing wall at the Santa Clara amusement park and took the first step up toward a lifelong passion for climbing.

“I’d always climb bookshelves and trees and lampposts,” Levin says of his younger years.

Levin, a 2012 graduate of Fremont High School, is a contestant on the NBC show that challenges athletes to compete in grueling obstacle course challenges.

On the June 1 episode held at Universal Studios Hollywood, Levin survived the qualifying round. Of 100 competitors, Levin was one of 30 to move onto the finals. The top 15 finishers of various city finals will move onto another round in Las Vegas. That episode will air July 11 and will reveal whether or not he moves forward to the national finals.

As a longtime fan of the show, Levin first became enthralled by the show’s concept when watching the original Japanese version of the show. He was attracted to both the amazing athletics on display as well as the mental component of the competitions.

“Watching it on the Japanese show, I was like, ‘That’s super fun.’ It’s very similar to climbing, where you aren’t rooting against someone. You’re working together to defeat these hard obstacles,” says Levin.

He applied to be on the American version of the show in January and was chosen from a pool of 75,000 applicants for one of the show’s 600 slots. As soon as he knew he was going on the show, Levin began training at a gym called APEX Movement NorCal in Concord that has an “American Ninja Warrior”-like obstacle course. There he was trained by a former contestant, Brian Kretsch, who gave him tips on how to succeed with both the mental and physical obstacles.

“One of the biggest things you don’t really get from just watching the show is that the biggest challenge is mental,” said Levin. “Not only do you have to compete in front of all these bright lights and cameras with millions watching, the episode is filmed outdoors at night as they can only film at night. You are expected to run at any minute without notice. They film from 4 p.m. to 5 in the morning and you have to be awake the whole night.”

Episodes were taped in April, and Josh is sworn to secrecy on how he performed. During the national finals round in Las Vegas, contestants will face a four-stage course modeled after the Mt. Midoriyama course in Japan. The winner takes home a grand prize of $1 million.

Levin says that the whole experience has been great, and he and his friends are planning to audition for a college edition of the show.

Climbing has been a major part of his life since that fateful climb at Great America. When he was 5 years old, a neighbor gave him a pass to Twisters Rock Climbing Gym in Mountain View. He admits his shy personality as a child made it hard for him to excel during group lessons, so his coach Stacey Collver offered to give him private lessons to boost his confidence.

Two years later he was climbing competitively and went on to win numerous climbing competitions. He also practiced mixed martial arts at Sunnyvale Martial Arts Academy and along with his mother, learned Chinese acrobatics and participated in trapeze training. While in high school, he was founder of the Fremont High School Climbing Appreciation Club. At 20 he competed at the Summer Youth Olympic Games in Nanjing, China in rock climbing.

He credits all of those experiences for his success on “American Ninja Warrior.”

Now, 22 and a senior at Northeastern University he decided to use his appearance on the show to pay tribute to Collver. In 2003 she was diagnosed with a rare lung disease Lymphangioleiomyomatosis, or LAN, which required her to have a double lung transplant in 2004.

“As someone you look up to as a coach you think they’re a superhero. To have that mentality and see that happen, it shattered my perception and it was tough for me. It made me realize life is short; you should do something you’re passionate about,” he says.

Collver is on the waiting list for her second lung transplant. On the television show, Levin wore a bright green bracelet to encourage people to become organ donors, a cause that he’s taken up in honor of Collver.

While on the show he spoke about the importance of signing up to be a donor and encouraged viewers to visit donatelife.net and register as organ donors.

As for anyone interested in replicating some of the athletic feats on the TV show, Levin suggests budding ninja warriors train hard and take up rock climbing.

“I recommend starting out with rock climbing for giving the best overall base of strength, coordination and problem solving to compete on something like this,” he says. “It’s challenging, but not impossible.”

Visit nbc.com/american-ninja-warrior. For more information about the nonprofit raising money for Stacey Collver, visit helphopelive.org/campaign/748.