Last week I took a trip to TheAltitude Centre in London to get some advice from the experts about how I might cope with the altitude in the Himalayas.
I will be running at a maximum of around 3500m for half of the event. At that level oxygen is around 13% compared to 21% at normal sea level. It will add another dimension to the challenge and could make things very uncomfortable, so I was keen to find out how I might cope and what strategies I could take to prepare better.
The higher you go, the oxygen level in the air decreases and your body has to work harder to sustain the same pace. Some people have an unfortunate reaction to altitude and suffer mountain sickness, nausea, headaches and is often so debilitating, they don’t make the summit or complete the event.
The Altitude Centre, London boasts the biggest altitude chamber in England and is situated near Cannon Street in the City. Staffed by experts in sport science it is used by all manner of mountaineers, marathon and ultra runners looking to improve performance, but also by every day runners trying to lose weight or just to get an extra edge to their fitness.
The benefits of training at altitude mean that when you then exercise at ‘normal’ oxygen levels, your body is more efficient and able to utilise oxygen more effectively. Precisely the reason why elite runners train at altitude in the Rockies or in the USA, so when they return to sea level their performance is enhanced. Training in a hypoxic chamber is also vital to prepare if, like me, you’re going to be running at altitude or mountaineering. Even for recreational runners, training in a hypoxic state will raise your metabolism, aid weight loss and improve your fitness.
The main chamber (which contains a number of treadmills and spin bikes) is set at just under 2800m, which is around 14% oxygen. Immediately upon entering the chamber it felt cold and my breathing rate felt just a little higher, but nothing dramatic. Sam, a sport science student from Bath Uni, explained that my heart rate and blood oxygen level would start to decrease in response to the lack of oxygen, just by being in the chamber.
He then took me through a hypoxic sensitivity test to see how I’d respond to higher altitude. I had to breathe normally wearing a mask which delivered only 11% oxygen – the equivalent of being at 5000m. My heart rate and blood oxygen level started to drop immediately and I could feel myself need to suck in more air and breathe more deeply. Sam watched to see how quickly my blood oxygen level dropped to 85%. Average time is around 60 seconds. Longer is better. Mine took 130 seconds which means that (hopefully!) I’m won't be particularly sensitive to altitude sickness. Result! Sadly I can’t claim it’s because of any superior fitness or anything I’ve been doing, it’s just good luck and down to good genes.
In fact there is some evidence that elite athletes may actually suffer more at altitude. Onto the treadmill and I had a gentle run in the main chamber at 2800m. Interval training brings about the best results, so I’ll be going back to have a crack at some harder stuff to try and acclimatise before I go to the Himalayas. Fascinating stuff and another tick in the 'confidence' box.