More than 600 athletes are expected to compete in Toronto this week for the opportunity of representing Canada on an international level.

“I'd say I’m excited,” said olympian Penny Oleksiak, who spoke with CTV News Toronto while training at the Pan Am Sports Centre Pool. “I’m pitting all my nervous energy into excitement, so I’m trying my best to stay positive.”

The 16-year-old is one of many Olympic champions hoping to be chosen as part of the six teams representing Canada in prominent swimming competitions, such as the FINA World Championships and the Pan American Games.

A total of 627 athletes from 157 clubs across the country will compete in the Canadian Swimming Trials.

“Who will be on these other teams is putting themselves in a position to make the national team even stronger in 2020 because of the opportunity that’s available to them in 2019,” said Swimming Canada High Performance director John Atkinson in a statement.

“An example of that is Kylie Masse, who won a gold medal at the World University Games in 2015, went on to the trials in 2016, made the team and was an Olympic medalist at the end of Rio. Penny Oleksiak and Taylor Ruck went to the World Junior Championships in 2015 and both went on to win medals at the Olympics.”

Masse, 23, told CTV News Toronto she is hoping to represent team Canada again this year in the world competition.

"It was a dream come true to qualify for Olympic team, actually at this pool, in 2016 and then to have gone on to the Olympics and to have won a bronze medal I couldn't have imagined it," she said.

Being able to qualify for the Olympic Games in Tokyo in 2020 is the ultimate goal for many of the athletes competing in the trials and is the reason many of them train about 25 hours a week.

“I think just to do well and be happy with myself and instead of trying to make everybody else happy, actually making myself happy with everything that I’m doing and how I’m swimming,” Oleksiak said.

The trials are scheduled to take place in Toronto between April 3 and 7.

With files from CTV News Toronto's Janice Golding