The former Formula One driver, who lost his legs in a horrific race car crash in 2001, became a champion on the road again this week. He was competing in handcycling, a sport in which the bike is powered by the arms.
But it's not the feeling of winning the 45-year-old Italian will miss the most — it's those countless hours of hard work and meticulous planning that got him there.
"I'm certainly very, very happy but this moment also brings a little bit of sadness because this weekend is going to be the end of a great adventure I've been fortunate enough to live," Zanardi said outside the boisterous sponsor party to celebrate his first win.
While the party roared on in another room, he reflected on what it all would mean come Monday, when the games were over.
"You know, when you are in your 20s, you always believe that the race, that the championship is the only thing that matters," he said. "But then 20 years later, you say 'Ooohhh, I remember when I was there with my mechanics, with my engineer, talking about the car, going out for a pizza, going to the team and (fixing) my seat and (spending) time with them.
"So you realize what really (matters) was the effort that you put in daily in order to build something special. Because when the championship arrives, you cannot expect to meet happiness that day, otherwise you don't get there. It's the process."
That doesn't mean the driver, who admits he has "a little bit of a big head, hasn't loved every second of the actual games as well.
In one of the more enduring images of the 2012 London Paralympics, he slid out of his cycle after winning Wednesday's time trial, sat on the track and, with one hand, hoisted his bike in the air. It seemed weightless compared to the effort it took to get to that track in the first place.
The victories at Brands Hatch, the London track where he once raced cars, capped an amazing journey for the 45-year-old Italian. The two-time CART champion spun out of control while coming out of a pit stop at the American Memorial 500 on Sept. 15, 2001, veering onto the track and into the path of Canadian driver Alex Tagliani.
The reinforced carbon fiber cone of Tagliani's car sliced through Zanardi's steering well at nearly 200 mph. His legs disintegrated.
Zanardi recalled that at the darkest point of his rehabilitation, it meant a lot to hear someone using prosthetic legs tell him he would walk again. He's not out there claiming to be an inspiration, but he knows firsthand that people struggling to overcome a challenge take solace in seeing it overcome, rather than just being told it can be.
"So I would imagine that probably a lot of people watching me doing (this) — to some degree against all odds maybe — they are going to say, 'bloody hell if Zanardi did this, I can try. I can try,'" he told The Associated Press. "A good attempt always brings a result."
As part of his rehabilitation, Zanardi took up handcycling, which uses a vehicle powered by the arms that features two coasting rear wheels and one steerable front wheel.
He heard about the sport by chance. Zanardi and another athlete had both tried to pull into a disabled parking spot, setting off a dispute as to who should get it. He saw the other man's handbike on top of the car and got curious.
Two years later, he proved he had become the best in the world.
What's next for Zanardi is still unclear, but there's a good chance it will involve some kind of competition. He mentioned a desire to race at the Indianapolis 500, but it could be something else, too. If you have passion, he says, everything comes naturally.
"You cannot talk about dedication, sacrifice or stuff like that," he said. "You just do what you have to do because you love to do it."