Once, when I was in my mid-twenties, I climbed Mount Fuji. Looking back on what turned out to be one of the longest days of my life, it was an ill-advised thing to do.
To be perfectly honest, it didn't even seem like a bright idea at the time. My mate Takeshi – who could reliably be described as "cheerfully optimistic" in even the bleakest of circumstances – was responsible for recommending the misadventure.
"I dunno. How hard is it?" I enquired after his suggestion that we climb Mount Fuji for fun. "Oh, I'm sure it will be fine," he chirpily replied. Famous last words.
A harrowing 15-hour, multi-tumble hike later ended in the pitch-black of a Shizuoka night and me vomiting profusely throughout the car ride home thanks to a rather jolly bout of altitude sickness.
I vowed then and there to never take another one of Takeshi's suggestions at face value, particularly after we'd just sunk an Asahi or three in one of the local izakayas dotted around Shizuoka Station.
Yet, having actually accomplished the feat, I'm glad I climbed Mount Fuji. In fact, many of my favourite sporting moments – if you can call me sliding face-first down Fujisan "sporting" – occurred in Japan.
Perhaps my favourite was watching the legendary Italian football club AC Milan destroy Argentine giants Boca Juniors 4-2 in the 2007 FIFA Club World Cup Final in front of just under 70,000 fans in Yokohama.
I'd blagged my way into the press box that night to watch an imperious Kaka deliver a one-man masterclass in attacking football. The Brazilian was named Man of the Match and the following day, FIFA's World Player of the Year.
I've watched a lot of football in Japan, principally following the fortunes of Shimizu S-Pulse – one of the J.League's most popular sides and the first professional team in Japan to have been created from scratch.
Their Nihondaira Stadium home, which overlooks the Pacific Ocean and offers panoramic views towards the omnipresent Mount Fuji, is undoubtedly one of the most picturesque in world football.
The walk up to Nihondaira is like an exotic cross between Luton Town and old-world Japan; neat terrace-like houses press up against a narrow residential street, before the winding road suddenly swerves to accommodate rows of cherry blossom trees leading up to the stadium forecourt.
Following Shimizu's fortunes on the road has proved no less exotic.
I've eaten deer on the bus ride up to watch Kashima Antlers, smuggled beer into Omiya Park, marvelled at the hordes of Urawa Reds fans inside Saitama Stadium and squeezed on to the terraces for a rare Yokohama F. Marinos home game at Mitsuzawa Stadium.
I'd thoroughly recommend heading to a football game to experience the real Japan, with its massed ranks of fans chanting in hypnotic unison, it's exotic game-day fare and the friendly atmosphere pervasive throughout.
Attending a J.League game is often as simple as showing up at the stadium on game day and buying a ticket, although for big matches it's advisable to find a Japanese speaker to help you pre-purchase one from a nearby convenience store.
You'll need no such help getting into the sumo, with the grand old sport one of Japan's most foreign-friendly activities. Not only can you download an English-language guide to getting into the sumo at Tokyo's legendary Ryogoku Kokugikan, you can even hire returnable headsets to listen to NHK's English-language commentary!
Ryogoku Kokugikan is a modern facility, having opened in 1985, but the on-site museum offers a fascinating glimpse into sumo's storied past, with the displays changing on average six times a year.
No visit to Japan would be complete without taking a trip out to the ballpark. While sumo might be Japan's most popular traditional sport, baseball has proved wildly popular ever since its introduction back in the 1870s.
Today, six teams each ply their trade in the Central League and Pacific League – the two professional leagues which concurrently make up Nippon Professional Baseball – with the winners of each league meeting every season in the Japan Series to decide the champions of the nation.
From the hallowed confines of Koshien to the spanking new surrounds of Mazda Stadium, Japanese ballparks are a mixed bunch, but wherever you catch a ball game, you're sure to enjoy yourself.
It's the same pretty much everywhere in Japan. You'd be hard-pressed to find a friendlier place to visit, meaning that when it comes to sport in Japan, you're bound to have a good time.