At the age of 50, many athletes are ready to make a switch, say, from racquetball to rowing, or basketball to bowling — or kick-boxing to kite-flying with the kids. Something a little easier on the body. It's not usually a time to gear up for greater physical challenges.

But Jeff Kozlovich, 50, of Hawai'i Kai, is not most people. Not by a long shot. He has committed to 2,817 miles of adventure during his 50th year.

What will those adventures be? You name it: paddling, swimming, biking, hiking, running, sailing — anything — as long as it's outdoors.

WHY 2,817 MILES?

Kozlovich came up with the number because he is inspired by Katie Spotz, a 21-year-old who rowed 2,817 miles solo across the Atlantic Ocean to raise money for the Blue Planet Run Foundation (www.blueplanetrun.com). She raised nearly $90,000 for the organization, which seeks to provide safe drinking water for people around the world.

"I was inspired by her, and when she finished I thought, 'I'd like to do something like that,' but I have a job and a family with three kids and I can't be taking off like that, but I felt bad and wished I could," Kozlovich said.

Instead, he will log the miles closer to home, with a goal of raising $25,000.

"I don't know yet how I am going to accumulate those miles, but I will figure it out," Kozlovich said with characteristic conviction.

Kozlovich has a busy life, with a wife, Beth Ann, who works for Hawai'i Public Radio, three sons, ages 17, 20 and 23, and two jobs: city lifeguard and personal fitness trainer.

LATE TO LIFEGUARDING

How Kozlovich came to become a lifeguard is another interesting story. While many lifeguards are about ready to retire at age 45, that's when Koz-lovich first became one.

For years Kozlovich was in business. "I know there are other things that make more money, but, well, basically I was doing it for money — but there was so much stress and I wasn't happy, and I didn't like the way I felt, so I decided to rearrange my life. I belong outside," he said.

At 44, Kozlovich started to show up for the tryouts for lifeguard. "My take was: 'I've had a lifetime of physical fitness, and I know I can do this,' " he said. "Ocean Safety's take on it was that they like the balance of people who are more mature and have more experiences and are a little calmer, so they were fine with it, as long as I could do the physical fitness part."

He has been a lifeguard for six years.

"I absolutely love it," he said.

Kozlovich compared the work of a lifeguard to that of a professional athlete — but with added responsibility.

"People who are professional basketball players could have a bad day and lose a game; we have a bad day and someone could lose their life," he said. "People are counting on me to be physically fit. I have to be my best every day.

"As a lifeguard no one gets a break just because they're older."

ENDURANCE ATHLETE

Kozlovich can't remember a time when he wasn't athletic. He played football, basketball and baseball in high school. He began surfing at age 11 or 12.

"To this day it's an important part of my life," he said. "I like doing so many different things but if the surf is good I go surfing."

He also has done about 100 triathlons over the years.

Kozovich is perhaps best known as a paddler, having completed the grueling Moloka'i paddle board race.

Last year, as a fundraiser for the American Lung Association's Hawai'i Chapter, Kozlovich ran from Magic Island up over the Pali and down to Kailua Beach Park, where he got on his paddleboard and paddled back to Ala Moana Beach Park.

Less than a year ago, at age 49, his devotion to fitness took another turn. Kozlovich decided to become a certified personal fitness trainer.

While many trainers work from gyms and health clubs, he insists on taking his clients into the great outdoors. Whether it's climbing the Koko Head stairs, stand-up paddling at Ala Moana Beach Park, a run around Diamond Head or pull-ups in Kapi'olani Park, his clients' workouts take advantage of what O'ahu has to offer.

FUELING HIS BODY

Like many serious athletes, Kozlovich views food as fuel.

"I eat real food," he said. "If it has to have a nutrition label, I don't eat it. I stick to that at least 95 percent of the time. I eat eggs or fruit salad for breakfast. I do eat lean meat, as well as nuts, berries, grains, the whole thing. As close to a natural food diet as I can."

He eats a healthy breakfast and small meals throughout the day: "a lot of almonds and blueberries, as well as whole grain pastas, brown rice and vegetables."

Eating a large meal in the middle of the day would not be the best thing for him while working, he said.

When discussing his nutrition, Kozlovich said, "It's more what I don't eat, packaged foods, snack foods. I don't believe in supplements. They never did anything for me.

"Food is more than just the vitamins that are in it. It's better to focus on eating healthy food than eating junk food and trying to make up for it with supplements."