Sue Stockdale's North Pole adventures made her stand out in the Oxfordshire business community.

Sue Stockdale

But on Channel 4 on Saturday, April 17, Ms Stockdale will be seen really putting herself to the test, as she comes close to drowning in pursuit of the TV channel's SuperHuman title.

The SuperHuman programme, devised by academics to find Britain's most extraordinary man and woman, shows her in a simulated helicopter crash and going for two days without sleep.

The programme makers expected competitors to display fearlessness, extreme endurance and emotional intelligence.

And as the head of a company called Mission Possible, 37-year-old Ms Stockdale was well placed to deal with almost everything thrown at her, including oxygen deprivation and extreme G-forces.

But Ms Stockdale, from Faringdon, revealed that she came close to drowning during the simulated helicopter crash. She said: "We were taken to a place in Dorset, where RAF pilots are trained, and the idea was to test memory under extreme pressure.

"We had to escape from a capsule in a large swimming pool. I panicked and thought I was going to drown."

But she also had to steel herself for a 150ft bungee jump. She said: "That was to test our fearlessness. Unfortunately, I have a real fear of heights. As part of my job I teach relaxation techniques for business people, so I was really able to find out how well they worked. I really enjoyed taking part in the programme to test my own capabilities."

Ms Stockdale was selected to take part from 2,000 applicants. A successful business development consultant, she was the first woman to walk to the Magnetic North Pole. She has been on expeditions to Antarctica and Greenland, and represented Scotland in 3000m and cross-country events. She has also written a book called Kickstart Your Motivation.

The series producer, Barbara Lee, said: "The series is the ultimate test of physical and mental excellence. All of the contestants are extra- ordinary in their own rights - they came from varied backgrounds including a diver, former Marine and academics."

SuperHuman will be screened on Channel 4 on Saturday at 7pm.