Yuki Kawauchi, who became the first Japanese in 31 years to win the prestigious Boston Marathon Monday, said in a post-race press conference it was the miserable weather conditions that gave him an edge.

Kawauchi said he has always been comfortable running in the cold and knew before the men's race on the notoriously hilly course that he would be able to make a strong bid should conditions turn.

And he got his wish.

The cold, wet and windy day which saw the Boston Red Sox Game at Fenway Park rained out allowed Kawauchi to overhaul Kenyan defending champion Geoffrey Kirui in the final two miles to win in 2 hours, 15 minutes, 58 seconds -- the slowest winning time since 1976.

"I'm good at cold weather races. I ran here (at the Marshfield Marathon, 30 miles from Boston) in January and knew I had a chance. If it weren't for these conditions I wouldn't be sitting here."

Kawauchi is a true athletics iron man, having run 12 full-distance marathons and 13 half marathons last year. The Saitama native was competing in his 81st career marathon in Boston, but this was just his first major crown.

Before Monday, he was best known for owning the world record for the most sub-2-hour, 20-minute marathons -- he has racked up 78 in his running career.

(Kawauchi settles for ninth at the world athletics championships in London in 2017)

When asked why he competes so much, the 31-year-old Saitama Prefectural Government worker said he loves to race, travel the world and uses the challenge to stay motivated and disciplined.

"If I trained by myself I wouldn't be able to put in the same quality, so I put pressure on myself by running races."

The Boston Globe called Kawauchi "an amateur from Kuki, Japan" and a "self-coached iron man." Reuters said Kawauchi is "known as the citizen runner because he also has a full-time job," while the Associated Press noted he is the first Asian runner to win the race since 2001.

Kawauchi said he kept Toshihiko Seko, the last Japanese to win the Boston Marathon, in mind over the 42.195-kilometer race between the suburban town of Hopkinton, Massachusetts, and Copley Square in Boston.

"I was born the year (1987) when Seko-san won. I couldn't help but feel the hands of fate in this. I was thinking he must have enjoyed the same scenery I did as he ran," Kawauchi said.

Kawauchi said life is not just a downhill slide from youth, and he feels like he has just proven to the next generation that one can perform at peak level beyond their so-called prime.

"People were talking about my performance decline after reaching 30, but now that I've won the Boston Marathon, others might feel they can do it too. I hope I've given them that drive."