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It keeps him on his toes.
A Long Island ballroom-dance instructor doesn’t know the meaning of de-feet — running six marathons barefoot, including four in New York City.
“I do get, periodically, a little shard of glass or something in my foot, and what I say is that that’s what the bib pins are for,” quipped 57-year-old shoeless sensation John Mazzei of Lindenhurst to The Post.
“I could perform minor surgery on my feet now.”
Mazzei is used to getting looks, including during training, stomping on jagged roadside pebbles and other debris while running on the island’s bustling streets.
“I actually one time got pulled over by a police officer while I was running barefoot training for the [NYC] marathon,” the quirky runner recalled.
“I guess they thought I robbed somebody, but I said, ‘Actually, I was doing an 8-minute mile.’ ”
Mazzei won’t be running this year’s Big Apple 26.2-miler — but only because he’s working to qualify for the Boston Marathon.
He has already heard it from marathon-route onlookers and folks in honking cars over the years, such as one Big Apple race fan who recognized him and yelled, “Barefoot John!” from a fire escape as he ran along.
“People say, ‘Hey! You forgot your shoes! And I’ve come up with the line back – ‘I just forgot to tie them and ran right out of them,’ ” he said.
Before going barefoot in the park while trotting through Manhattan for the New York races, Mazzei would run the conventional way — with socks and shoes.
He first got into running around 43.
But after just three months, his sneakers were ironically causing more pain on his knees than being barefoot ever has.
So he stepped away from running for a few years. It was only after reading Christopher McDougall’s “Born to Run,” which focuses on the sports science behind barefoot running, that Mazzei gave it another crack — sans shoes and socks.
“I think because I’m a dancer, I love teaching technique,” said Mazzei, who “hasn’t had any issues” with his knees since.
“I love the concentration, studying the technique of barefoot running.”
His new journey began with baby steps outside his house that turned into a 5K and even greater distances, which conditioned his feet for the more gargantuan tasks to come.
“The hardest thing to run on is gravel,” Mazzei said. “I’ve done trail running and trail half marathons and that stuff barefoot.”
Foot damage on regular pavement has been mainly incidental, but Mazzei brutally remembers suffering blood blisters on the balls of his feet while running on a track during one scorching day.
“That laid me up for a month or so,” he said.
Mazzei opted for his first New York City marathon in the early 2010s to honor his uncle, Thomas Stone, who was diagnosed with ALS. He nailed it in 3 hours and 48 minutes.
“When I’m doing the New York City Marathon, running in the center of the road is a lot cleaner anyway,” Mazzei said. “Still, you get into certain parts of the city that are rougher than others.”
Queens was “the gnarliest” thanks to jaggedly filled potholes, but “I’m not feeling anything adverse on my feet or anything,” he said.
“I just keep going,” added Mazzei, who has also run the Long Island Marathon.
Mazzei took his years of progress all in stride and even opted for an impromptu marathon in upstate Goshen – just because he felt like it.
“They were surprised I signed up that day. ‘Oh, you’re signing up for a marathon today?’ Did you know you were going to do this marathon? I said I didn’t really,” he recalled.
The legend of Mazzei has even grown in the top heats of the running world.
Meb Keflezighi, the 2009 New York city Marathon winner, once signed his foot for good luck along with the message, “Run to win” at an expo.
“I’d say the people you meet definitely are the most rewarding part,” Mazzei said.
“I do get those looks like I’m crazy or whatever. But it works for me.”
