We all know that training at altitude is meant to improve your cycling. But how high is too high, and how long is necessary to stay in the mountains - or inside a tent - to achieve any real benefit?
In the latest Form & Fitness feature on Cyclingnews, an expert on altitude training, Dr John Hellemans, answers the most commonly-asked questions about altitude training.
And as all non-climbers readily admit, the best part of riding in the mountains is descending. In the article, there are also details on what is possibly the longest descent in the world - how does some 4,345 of pure altitude drop in one day's riding sound? Certainly, there has to be some reward to gasping to the starting point at over 5300 metres. For more details, see The highs and lows of altitude training.