HOLLYWOOD actors Jake Gyllenhaal and Josh Brolin spent time at the University of Portsmouth to prepare for their roles in the disaster film Everest.
Ahead of the release of the movie today, it has been revealed that the A-listers used the extreme environments laboratories at the university back in December 2013.
It can be quite shocking for people preparing to enter an extreme environment to realise how debilitating it can be and how important it is to prepareProfessor Mike Tipton
The stars, their fellow actors, director Baltasar Kormákur and film researchers spent time in simulated high-altitude freezing conditions to find out how their bodies and ability to think would be changed in extreme cold and at high altitude.
They worked with world-leading expert on survival in extreme environments, Professor Mike Tipton and his team.
The film crew visited ahead of filming in Italy, Iceland and Nepal.
The film comes out in British cinemas today.
Everest is based on the book Into Thin Air: A Personal Account of the Mt Everest Disaster, which recounts a real-life tragedy in 1996 when climbers fought for survival after a storm. Much of it was filmed on location at Everest Base Camp.
Prof Tipton said: ‘At extreme cold, the body slows down considerably as does the ability to think rationally or to string a coherent sentence together.
‘It can be quite shocking for people preparing to enter an extreme environment to realise how debilitating it can be and how important it is to prepare.
‘Preparation helps partly by acclimatising people, and partly by ensuring they expect people might behave out of character.’
The crew’s preparation included spending time in the cold chamber, set to -20C and to 5,000m altitude to mimic the temperature and oxygen levels at Everest Base Camp.
The crew had a talk on the body’s reaction to cold and altitude from Prof Tipton, and after quizzed him on the limits of human survival, and how cold affects the ability to think, breathe and speak.
The researchers are regularly approached by journalists and film-makers.
Team GB open water swimmers visited the labs ahead of the Beijing Olympics to test themselves in the exact climate and water temperature they would face in China in a bid to help them shave off fractions of a second on their times.