"BEAST," the hat says. Because for the next two hours, that is what the Fairview police chief will become.
With his duffel bag slung over one shoulder and his wireless Apple AirPod headphones in his ears, Kahn makes his way from the treadmill to the weights at the Maywood gym off Route 17.
He slides his bag off his shoulder and turns up the volume on his phone. He picks up a pair of 100-pound dumbbells and locks eyes with his toughest critic in the room: himself.
"If I don't do something, I feel empty."
Kahn, 46, has become his own worst enemy. But he says it's for the better.
Despite being a lifelong athlete, Kahn wasn't serious about fitness or his health until recent years.
Growing up in Fairview and attending Cliffside Park High School, Kahn was the "chubby kid" on the baseball and wrestling teams, he said. He always took an interest in sports and fitness, but it took a major event and years of consistency to get him to where he is today.
In May 1999, when Kahn was a patrolman in the department and expecting his first child, he lost his mom to health problems at just 56 years old.
For more than a decade, Kahn continued ordinarily. He worked his way through the ranks at the police department and welcomed two more babies with his wife along the way.
It wasn't until 2010 that the reality of his mother's death set in.
"My mom never got to see any of my kids," said Kahn in between sets on Tuesday morning. "It got to a breaking point where I decided to make a lifestyle change."
Kahn has spent the better part of the last decade reinventing himself -- in the process becoming one of the most motivating members of Bergen County law enforcement.
Coming to the gym every day before work is non-negotiable. It's where he clears his mind and betters himself, finding new ways to grow and mold his body, all while motivating others.
Craig Behnke of Paramus has become one of Kahn's closest friends at the gym. The pair met years ago when HackensackUMC Fitness and Wellness Center first opened.
They train together almost every day, and Behnke says his workouts aren't the same without his partner.
"If I came by myself I'd just go through the motions," Behnke said as Kahn prepared the next exercise. "But he really pushes you, and he won't let you slack."
And he won't let your spirits get down, either. The pair laughed as hard as they worked for the entire morning, cracking jokes and improvising exercises as they went.
"We have a lot of fun -- you have to," said Kahn, who greeted almost everyone he knew that morning in the gym with a smile or a fist bump.
Finding new ways to shock the body and then sharing the wealth is what keeps Kahn motivated. He recently started a trend at the gym using resistance bands on different lifts, something he picked up on social media from New England Patriot James Harrison.
This week, Kahn is launching a new brand, Fit And Blue on Instagram and Facebook, taking his passion to the next level. He's staring with a new Instagram page, where he will continue to post exercises for all to see.
"You don't have to be an expert," he said. "You just have to have a working knowledge. If you try to become an expert in anything, you're just going to burn yourself out."
Open Kahn's refrigerator at work and it's clear his passion for fitness spans beyond the weights. It's stocked with individual cartons of protein drinks, BCAAs and healthy snacks. He even takes on occasional joking by the rank and file for keeping a single-serve blender in his office.
He hopes to lead by example at the police department as he does in the gym.
Just as the sun was beginning to rise Tuesday morning, Kahn scooped up his duffle bag and prepared his body for the last part of his workout. He always wonders if he's done enough.
"'Did I go heavy enough? Did I go long enough? Could I have done more?'"
Kahn walked upstairs to the second floor and began unraveling two hand wraps, carefully weaving the cloth in between his fingers and around his wrists.
Everything Kahn does in the gym is done carefully, thoughtfully, meditatively.
The chief raised his tattooed arms up to his chin and began rotating them rhythmically in a circle. With them, the speed bag hit the wall first faster and faster, and then slower and slower (SEE VIDEO ABOVE).
"You get a little older and a little wiser," he said, this time just a bit out of breath, "and you realize that health is more important than just getting big."
Email Martin Kahn at fitandblue@gmail.com or follow in on Instagram @fit_and_blue
Think you're the fittest police officer in Bergen or Passaic county? Know someone who is? Email clevine@dailyvoice.com to be featured in the new Daily Voice series, "Fit Cops."
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