Head for Heights?
- 16/01/08 - Sir Edmund Hillary, conqueror of Everest, died at the ripe old age of 89 last week. But maybe he would have lived to 100 if it wasn't for all that racing up and down mountains. Chris Billings explains why climbing isn't a good work out - for the brain, at least.
Although hanging off the edge of a mountain isn’t everyone’s cup of tea, for some, it provides the ultimate challenge - and thrill. But be warned: even if you think you have a head for heights, your brain might beg to differ.
Spanish researchers concluded only last year that most high altitude climbers suffer some irreversible brain damage as a result of their adventures. Of 35 high altitude climbers studied, all but one showed some form of damage when their brains were scanned using MRI technology. Some of this damage is otherwise only seen by doctors when examining the brains of elderly patients. And according to the study, amateurs appear to be at a higher risk than professionals.
The brain is more susceptible to injury through lack of oxygen (hypoxia) than any other part of the body, and hypoxia has long been known to cause this type of damage. But how high do you have to go before the air starts to get really thin?At 7600 metres, the air only holds a third of the oxygen it does at sea level, but altitude sickness can strike as low as 2400 meters. The highest peak on Earth, Everest, stands 8850 metres tall by comparison. Bottled oxygen can assist, but climbers usually only supplement at the highest of elevations, otherwise forcing their bodies to adapt in stages. When hypoxia strikes, symptoms can range from headaches, fatigue, euphoria, nausea and shortness of breath, to more severe effects such as changes in consciousness, seizures, coma and death.
Everest is an obvious target for elite climbers, has done a lot of damage in the years since Hillary and his partner Tenzing Norgay became the first to make it to the top in 1953. The pair used supplemental oxygen, but in 1980, Reinhold Messner managed a solo climb without any additional aid.
More than 2000 people have now successfully climbed Everest and, astonishingly, over 100 of them have used no bottled oxygen. But of course, Everest is only the tip of the iceberg – or mountain, as it were. There are 14 elite peaks in the world over 8,000 metres, and with over 2000 climbers making their way to the top of these each year, its quite possible that the number suffering brain damage from their sport is actually quite high.Although this is bad news for climbers, it is a welcome victory for couch potatoes, who have said all along that such things are senseless and dangerous.
- 16/01/08 - You might have seen Michael Portillo's quest to find the perfect killing machine on BBC's Horizon programme last night. Pretty good it was, if a little disturbing. And hypoxia featured quite heavily in it.
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Image: Sarah Brucker
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