The long-distance runner is famously lonely. The long-distance swimmer is not only lonely but often afraid.

Sometimes it's just the swimmer and a vast ocean. No competitors in sight. No comforting landmarks or safe harbors. No noise. Nothing but the waves to disrupt the solace, the fear.

When Fran Crippen introduced him to open-water swimming a few years ago, Arthur Frayler "freaked out." As they swam alone in the Atlantic Ocean off Florida, the youngster wouldn't let his mentor get more than a few feet away.

"It can be real scary," said Dick Shoulberg, who coached both Crippen and Frayler at Germantown Academy. "There's no black line. It's just you and the ocean, the lake, the river. It takes a certain mentality to compete."

With Crippen, a world-class open-water competitor, as his instructor and inspiration, Frayler eventually took to swimming's equivalent of the marathon. Then, in October 2010, during a 10K race in 86-degree water off the United Arab Emirates, Crippen drowned.

Though the 26-year-old's death devastated Frayler, it also motivated him. Crippen, who would have been one of the favorites in the London Olympics this summer, has remained a living presence for the GA senior. He still hears Crippen's voice. And for more than two hours on Friday, as Frayler vies for an Olympic berth in the 2012 Open Water National Championships in Fort Myers, Fla., it will propel him.

"Without a doubt, he'll be behind me, motivating me, pushing me," Frayler said this week from Florida. "It's always important to focus on your race, because there's so much going on. But for me, it's important to keep Fran in the back of my head. He was like a brother to me."

So close was their relationship that in 2011, when Frayler tied Crippen's 500-meter record for GA's pool, he initially refused to challenge it again. But Shoulberg convinced him that's not what the late swimmer would have wanted. Frayler's resistance and Crippen's record soon disappeared.

A towheaded Staten Island native, Frayler, 18, has a real shot in Friday's 10K event at Miromar Lake.

"He's a contender," Shoulberg said. "At the Pan-Am Games last summer, after winning gold in the 1,500, he came back and nearly won the open-water [finishing second, just 0.03 of a second behind the victorious Canadian]."

Frayler's secret, Shoulberg said, is his passion for practice. He works out two hours each morning before school, trains three more hours in the afternoon, and then stays an extra hour after practice. On weekends, he increases the workload.

"I'm at that pool [GA's natatorium] more than I'm home," he said.

A diver originally, Frayler went to GA in fourth grade to work with Shoulberg and the world-class program he had built there.

"When he arrived, he wasn't real fast, but he was on a steady track," Shoulberg said. "What pushed him over the top was the training. He absolutely loves to train."

In 2008, Crippen, a GA graduate, introduced him to open-water swimming. Frayler's life and focus changed forever.

"He fell in love with the sport," Shoulberg said. "Fran really helped him and pushed him."

Then one day in the fall of 2010, Frayler and three friends were en route to practice when they got word that Shoulberg had canceled the session.

"That never happens," Frayler said. "I knew something was wrong."

Not long afterward, he got another call, letting him know that Crippen had drowned.

"I can't describe how I felt," he said. "I was in shock. It just didn't fit. I couldn't understand it. I mean, he was a swimmer. How could he drown?"

He soon became better acquainted with the grueling sport's dangers. In addition to the mental and physical discipline it demands, competitors have to be concerned with the elements and, most important, their bodies.

Last year, Shoulberg would not allow Frayler to compete in a 25K race in China because officials there insisted the race would go on no matter how high the temperature rose.

"My kid is not going to swim in those conditions," Shoulberg said.

At each event there are two or three in-water feeding stations, boats positioned at specific locations where swimmers can get a bottle of Gatorade or a power bar. Workers aren't allowed to come into contact with the competitors, so the nourishment is served via a long pole.

"You tread water, get a drink, and then toss the bottle," Frayler said. "You need it. In a two-hour race, your body uses a lot of fuel."

It's almost as important to stay mentally sharp. If a swimmer breaks away from the pack early, you've got to determine whether it's wiser to go with him or wait for the inevitable slowdown.

"You can never expect everything that can happen in open water," Frayler said. "You have to decide when to feed, when to follow, when to stay back."

Those two hours also leave plenty of time for reflection. And that's when Frayler communes with his late friend and teacher. This time, with a spot on the U.S. team that will compete in London at stake, that conversation should be intense.

"The Olympics has been a dream of mine," Frayler said. "Fran knew that. He will be right there talking to me, urging me to do my best."

Contact Frank Fitzpatrick at 215-854-5068 or ffitzpatrick@phillynews.com. Follow @philafitz on Twitter. Read his blog, Giving 'Em Fitz, at www.philly.com/fitz