The swimming hero helps spotlight the annual fundraiser, which raises money for Cancer Research UK and Marie Curie.

People of all ages and abilities can take part in the sponsored event, which will take place at Slough Pools from May 6-8.

The pools include Langley Center and Recreation Center.

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Mr Foster said: “Swimming is a fantastic form of exercise, with a wide range of benefits for your physical and mental health and is accessible to people with varying abilities and needs.

“So whether you’re an avid swimmer who’s in the pool all the time, prefer to be in open water, or just dipped your toes for the first time, Swimathon is the perfect challenge for everyone.

“That’s why I’m asking everyone to get involved and feel the benefits of this fantastic sport while raising money for two major charities, Cancer Research UK and Marie Curie..”

Swimmers can choose distances ranging from 400m to 30.9km and can compete individually or as a team.

And anyone unable to make it to one of the organized sessions can register for MySwimathon, which runs from April 29 to May 15.

Elisa Mitchell, Cancer Research UK spokesperson for Slough, said: “It doesn’t matter if you’re not the fittest or the fastest, Swimathon is such a fun and simple way to encourage people to swim – while supporting causes that are close to the hearts of so many.

“One in two of us will get cancer, but we can all support the research that will beat it.

“From proving the link between smoking and cancer to laying the foundations for modern radiation therapy, our scientists have been at the forefront of cancer research for 120 years, and we’re not stopping now. .

“That’s why we urge swimmers to dive this spring, raise funds and help us continue to invest in science today to deliver the treatments of tomorrow. Together, we will defeat cancer.

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Marie Curie nurse Janet Lockheart and medical assistant Amy Chellew will take on the Swimathon this year, having originally planned to do so in 2020.

Ms Lockheart said: “We decided to do Swimathon to raise funds to support the wonderful Marie Curie team and the people we care for.

“We have seen with our own eyes the difference fundraising can make for families who need our support, so to be able to do this for them and those supported by Cancer Research UK is amazing.

“Swimming is a great way to get in shape and raise funds, so we’re really excited – we’ve been waiting two years to say we’ve completed Swimathon.”

Go to Swimathon to register.