All of the athletes who run into the water Saturday for the Peaks-to-Portland Swim have something that motivates them. For many there are physical goals to attain, but a few have something else on their minds.

Westbrook resident Pat Gallant Charette began swimming in the event only after her brother, Robbie Gallant, suffered a fatal heart attack nearly eight years ago at age 34. Rob won the Peaks to Portland twice in the early 1980s and Pat, along with other family members, decided to honor his memory by completing the swim.

At first, Charette needed significant training to prepare for the 2.4 mile race.

“It took a year of swimming at Davan Pool,” says Charette, adding that by the 2004 Peaks she was in much better condition. “Last year I was feeling really strong, and last summer I swam across Big Sebago.”

Charette, 54, has been joined in the YMCA-sponsored event in previous years by her brothers Paul, Tom and David, as well as her son Tom. This year her son will cross the channel in a kayak, as will Charette’s daughter Sarah, while her brother Tom joins his sister in the swim.

Gorham’s Lisa Peterson will be participating in the Peaks for the first time this year, though she has thought about it before.

“I’ve always been a swimmer,” the 33-year-old says, “and this is something I’ve always wanted to do in my life.”

Peterson, who completed her first full triathlon last year, does have one small reservation about treading water in Casco Bay.

“The biggest challenge is getting over the things that could be swimming beneath me.”

Thom Bell’s friend John Fitzgerald talked him into signing up for the event several years ago. Now Bell, who is 47 and lives in Westbrook, says that the Peaks has become a “real personal thing” for him.

“It keeps me in touch with the swimming community,” he says. “One year when I didn’t do it I volunteered.”

Bell will swim the course for the fourth time this year, while for Cathy Kilburn, also of Westbrook, this will be swim number five.

“It’s part of my overall training,” says Kilburn, 39, a triathlete. “I don’t train extra for it.”

The bay, she says, is “cold and full of seaweed,” yet she loves the challenge.

“Running out of the water you feel great. It’s really satisfying.”

The 160 swimmers will depart from Peaks Island at 8:30 a.m. Saturday, with the leaders reaching Portland’s East End at about 9:10. More than 125 kayakers will also join in the event, which benefits the Cumberland County YMCA.