Other people's experiences may differ, but I have found that many of the rucksacks on the market with claims of back systems which will reduce the levels of perspiration do not work very well. It’s a little like the mistake of thinking that materials like Gore-Tex won’t make you sweat. It simply is, in most cases, not true. You still sweat in Gore-Tex, or Event, but this perspiration is transported away by the material in an attempt to limit the level of perspiration. This may not be true for everyone, some people perspire much more or less than others. The passive back systems on rucksacks are much the same. I’ve tried several packs and find that my back perspires regardless of the technology involved. More with some, less with others. When you have a rucksack on your back a micro climate is created between you and the pack where the temperature increases and you begin to perspire. This creates a highly humid space that I believe makes me sweat even more, much like hot and humid weather. In my case, it’s like the Tropics. What I have found is that my back perspires less with the Montane Medusa 32 I own as this has a quite small surface area in contact with my back. It’s this situation that has driven me to re-evaluate the rucksacks I own and possibly replace them with what maybe more comfortable alternatives. I’ve also made weight a bit more of a factor, so I decided to pick up one of the new Berghaus packs, the Vapour Light 20 day-sack.
