Thirty-four swimmers preparing to swim from New Brunswick to P.E.I. to raise funds for critically ill children this weekend say that their biggest challenge will be mental.

Kirk MacLeod is one of the participants in the Big Swim, a 14-kilometre swim in support of Cystic Fibrosis Canada and Camp Brigadoon.

After nine months of chemotherapy and nine surgeries, including one just this week, cancer survivor MacLeod needed something to work towards.

"I was pretty defeated in a lot of ways, and had lost focus. I was wondering, ‘What am I going to do with my life now? How am I going to get back on track?’ And the Big Swim really came out of nowhere and gave me that focus," he said.

Youngest female to make crossing

In the last eight weeks, MacLeod has worked on his swimming with a coach. Now he and 33 others say they're ready.

One of the participants,15-year-old Jessica Plummer, aims to become the youngest female ever to make the crossing.

"To be the youngest female ever to do it, that's something you can take with you and you can tell people, and they're like, ‘Oh that's really cool’ and it's something that's individual to you," she said.

Wetsuits and kayak support boats will help, but participant Suzanne Ferrier said in the end, crossing the strait is a mental game.

"When you're swimming for five hours straight and you’re in the water, you don't really see anything. Your face is in the water. It's a lot of time to spend with yourself, just thinking," she said.

Ferrier said thoughts about what the $100,000 raised can do for the children at Camp Brigadoon is a good motivator.

"I’ll remind myself we’re doing this for the children. It may be tough for me right now, but they have this every day," she said.

Help for kids

Camp Brigadoon gives children and youth living with chronic illness a support network where they can meet other children facing similar health challenges. It provides them a chance to have fun, instead of thinking about their illness.

If there's one thing MacLeod said he's learned from cancer, it's that our time is limited.

"I think for everyone doing The Big Swim this weekend, we are getting the most out of life," he said.

The Big Swim takes place on Sunday. The swimmers will leave early in the morning from the New Brunswick side of the strait and swim alongside the Confederation Bridge. With any luck, four to six hours later, they'll reach P.E.I.