When Nathan Stein was a student at Mount Crescent Elementary in 2003 he had no choice but to find a sport that was easier on his knees.

At the time, he was a budding soccer and water polo star. That was until he learned he had a debilitating condition called osteochondritis dissecans.

It is a condition where the bone at the bottom of the femur, the condyle, is underdeveloped and breaks away.

The Maple Ridge Secondary graduate's knee was operated on a dozen times before he was classified - in 2009 - as an Sb9. That's a paralympic classification that means he is a swimmer with minimal weakness affecting his legs and some deformity in his feet or minor loss of a part of a limb.

By the end of that year, despite his ever-changing abilities, he was competing for his country at the International Paralympic Commitee world championships in Rio de Janeiro and broke the record by three seconds in the 100-metre breast stroke.

Fast forward nearly a decade later and the young athlete now has a silver medal from the 2012 London Games.

The Paralympic hardware hangs around his neck near his 'No Surrender' tattoo inked over his heart.

When 20-year-old Nathan Stein questions his strength or when things get tough, the tattoo over his heart reminds him of how far he has come in such a short time.

For Nathan, the London Paralympics was an "amazing experience."

"Every moment is just so surreal, from finishing my race and getting to step on the podium," Nathan explained.

"It is just extra incentive to try to get better, gives me more confidence in myself. It was my first Paralympics, and I can only get better," he added.

The 6-foot-3-inch-tall athlete's journey is only on the starting blocks and he has already won the silver Paralympic hardware for 50-metre freestyle in 2012 and won the bronze medal at the 2011 Para Pan Pacific Championships. He also holds records in the 50-metre freestyle, 50-metre butterfly, and all breaststroke records in his category.

It wasn't always easy to forget about the other sports he excelled in.

His mother Heather Stein said that they learned that he was still trying to play soccer and other sports, even after being warned not to.

"Not a huge surprise," said Heather.

"There was a lot of pain in his leg and in his heart," she said.

To this day when Heather sees Nathan's surgeon the doctor mentions how shocked he was when he opened up Nathan's leg and the bone wasn't there. "He says he will never forget the look on his assistants face when they saw the space," said Heather, who recalls the first time the surgeon came to watch Nathan coach swimming.

"It was at a summer swimming provincial championship and Nathan was running down the pool deck with a stopwatch in his hand timing his swimmer while she won the 100-metre breaststroke from lane 8," Mom recalled. "While Nathan was running he caught sight of his doctor out of the corner of his eye and slowed to a walk."