Shortly after Rick Hansen survived a vehicle accident that left him paralyzed, the then 15-year-old decided he wouldn't let his disability hold him back.

Fast forward 50 years, Hansen is a household name across Canada and the world for championing accessibility rights and competing on the world stage.

But learning to live with his physical disability was not always easy, Hansen told CTV National News' Sandie Rinaldo.

"When you're in a situation like that, you're overwhelmed, you're in shock, you're in disbelief, and you have this big, dark canvas of despair," Hansen said. "The first thing that you need in those early days is some level of…'It's got to get better.'"

This year, Hansen marked the 50-year anniversary of the life-altering accident that left him paralyzed from the waist down.

At 15 years old, Hansen and his friend Don Alder hitched a ride in the back of a truck after a fishing trip on June 27, 1973. The pair were headed back home to Williams Lake, B.C. when the truck swerved around a corner, and they were thrown from the vehicle.

"We weren't going all that fast, and then literally we started just fishtailing," Hansen said.

Alder was able to jump from the truck bed before Hansen became trapped inside as it rolled into the ditch.

a young Rick Hansen

"I must have lost consciousness for a minute or two and then I woke up and I thought, Oh, I'm alive… I was just thinking for sure that this would be the end," Hansen said.

When he came to, he was sitting against a toolbox on the side of the road and realized his legs weren't working.

"I was pretty angry at the driver…I couldn't believe that he had done that," Hansen said. "I was just struggling…Deep down inside it was this sense of 'I'm in trouble…real trouble.'"

Despite the hardships he would endure — four months in the hospital and three months in rehabilitation — Hansen decided to change his mindset.

"I started to think, 'There's got to be something that I can focus on.' And it was rubber bands. (I) tied them to the side of the bed and started working my arms," he said.

Hansen wanted to sit upright before his 16th birthday in August, a goal he achieved and which gave him the motivation to keep going.

"When I first came back after my accident to Williams Lake, I started learning about what life was possible," Hansen said.

After encouragement from his volleyball coach, he started playing accessible sports, launching his athletic career.

Between 1979 and 1985, Hansen won 19 wheelchair marathons, three world titles and 15 medals — six at the Paralympic Games and nine at the Parapan American Games.

And through it all, he never lost focus on how he could uplift others who are disabled and raise money for spinal injury research.

"Success in life isn't about whether I can walk around and use my legs," Hansen said. "It's about my heart. It's about passion."

To hear Rick Hansen's full story, watch a special episode of CTV's W5 on Dec. 2 at 7 p.m. EST.

Rick Hansen