How will the altitude affect me?
The altitude affects everyone, certainly you will breathe more and move slower than you would at a lower altitude. One of the purposes of the warm up phase is to get acclimatized to a moderate altitude before attempting Mont Blanc. Indeed, if you are unable to get high enough for acclimatization, then you wouldn’t be able to attempt Mont Blanc, as it would be unsafe because you would be very likely to develop altitude sickness. During our initial meeting in Chamonix we talk about altitude and acclimatization in detail.