It is the contention of many that even with proper training and under optimum conditions anyone who chooses to run 26.2 miles, especially all at one time, must be crazy. If that is so, each year at the Honolulu Marathon we witness many varieties and levels of derangement.

There’s the common folly of undertraining. Granted, that’s usually more to do with ignorance than insanity. I met a couple of first-timers Thursday who maxed out at 15 miles a week and completing a 5K race in preparation for this. I wish them luck Sunday (and Monday), as they will need it.

Others handicap themselves with full awareness. Usually it has to do with some kind of costume.

Guys in banana attire — and other fruit suits, enough to make an underwear commercial. Women in wedding dresses. Men in wedding dresses. This year we will probably see more than the usual number of Star Wars characters.

Many marathons ago, I saw a guy running while wearing a beer can hat. Beer can hats were the rage in the ’70s, and if you remember them you may be asking what’s so crazy about that. Well, these cans actually had beer in them, and a tubular system transported the golden soda from the top of his head to his mouth.

My favorite is The Logos. No, Jerry West does not run the Honolulu Marathon. But on the second Sunday of December each year, about three or four guys bring the ancient Hawaiian warrior back to life. Their costumes are perfect, down to the footwear … none.

I can’t think of many things tougher than running barefoot for four or five hours, much of it on hot pavement. But I learned of a few Thursday at the marathon expo when the marathon’s social media director, Fredrik Bjurenvall, introduced me to Waikiki resident Jake Garvin.

Garvin describes himself as a scientific and technology security consultant for the government. I don’t know what exactly that means but it sounds scary, and although Garvin seems very friendly I know better than to ask for details — especially since he possesses the physique of an NFL linebacker and thorough knowledge of jujitsu and kung fu.

Did I mention he is 52? Multiply that by three and you get something close to the Cornell graduate’s IQ.

None of that is what makes Garvin special or crazy. And his fastest recent marathon doesn’t either; he “ran” it in about seven hours last year (which is actually quite an improvement over 10 1/2 hours in 2012).

“I’d be faster if I didn’t get stopped 250 times to take pictures,” he says. “I still beat several thousand people.”

Still, not impressive at all, and then you find out why his times are so slow, and why all those fellow marathoners want to take selfies with him. Garvin runs the course each year while carrying a huge log or cement block on his shoulder. In 2012, the log weighed nearly 100 pounds. In 2013, he decided to stop being such a wimp, and bolted some weights onto the log to get it over 100. Last year it was a cement block; a bit lighter, but more awkward to carry, if that’s possible.

“It dug into my shoulder a little, but no damage,” he says.

His only regret through all this was two years ago, when he soaked the log with the weights attached to it in water.

“Made it too heavy.”

So everybody, don’t forget that when you do this: Do not soak the log in water.

This year’s Bunyanesque feat will be unveiled Sunday at 5 a.m., somewhere among the thousands at the starting line.

Why does he do it? The answer is etched on the band on his left arm: “VEGAN.”

Garvin wants everyone to know he has eaten nothing but plants for more than 30 years, but still manages to maintain the physique of a professional bodybuilder half his age.

He adds that you can be a vegan and a great distance runner. Just look at Isabella Ochichi, a Kenyan police sargeant who is considered a strong contender to win Sunday after finishing third last year. No meat for her.

“And I have not been to a gym in 15 years,” Garvin says. “I exercise outdoor, I pick up boulders and rocks, a lot of pullups, maybe 300 or 400 a day. One day I did 3,000 pushups, to see if I could do it. Some crossfit guy was talking about doing 3,000 in a week. I said why wait? One day.”

But mostly it’s about what he eats, and doesn’t eat. He’s trying to set an example for others, trying to help them be healthier. Garvin is even more adamant after reports that bacon and other meat products can cause cancer.

“Walnuts are 24 percent protein, steak is 17 percent. Soy beans 40 percent. Vegans get more protein than meat-eaters,” Garvin says. “Cows don’t eat meat, how do they get protein?”

I don’t know. Remind me on Sunday to ask the guy in the steer costume who usually finishes in about six hours.

Reach Dave Reardon at dreardon@staradvertiser.com or 529-4783. His blog is at Hawaiiwarriorworld.com/quick-reads.