Swimming 100 lengths would be enough to test the stamina of everyone, but it promises to be extra difficult for Horncastle teenager Eleanor English.
She has had to battle serious leg problems all her life and has been on crutches for the last eight months after the latest in a long-line of operations.
Effectively, the Queen Elizabeth’s Grammar School student is learning to walk again.
Despite that, she will attempt a 2.5km swim at Horncastle Pool on Saturday May 30.
And the remarkable teen has plenty of incentives to succeed.
Eleanor is looking to raise funds to take part in the 2016 World Challenge when she is planning to visit Asia to take part in a number of community and educational projects.
She had to postpone her swim in March when she had to have one of the screws replaced in her legs.
Despite still having to use crutches, her consultant has said she can now start swimming and she will attempt to cover her very own marathon.
The fundraiser is slightly different as 50 per cent of the funds will go towards the Rainforest Ward and Safari Day Unit at Lincoln Hospital.
Eleanor says she wants to recognise the support the hospital has given her and other youngsters.
She said: “Every time I have stayed at the hospital, the nurses have looked after me wonderfully.
“For that reason, I want to give something back to support the wards.”
The money will go towards providing toys, puzzles and other entertainment while children are in hospital.
Eleanor - who has undergone numerous operations - has been on crutches for the last eight months.
Anyone, or any business, that would like to sponsor Eleanor can contact her on 01507 522159 or donate via gofundme.com/eleanorswimming
*Turn to page 15 for more on the QEGS’ students gearing up for their dream trip.