man there are some haters around here.
Alpynisto, absolutely, I don't do major expeditions. but you need a little more than anecdotal evidence. and I would accept it but really you don't provide any explanations. more like you just are regurgitating something.
I understand as expeditions get longer, the need for fat increases. 1 month treks? yeah you need some fat. where is the cutoff? I don't know.
Backing up, I dont' think the OP was specifically asking about extremely high altitude climbing only, and that's where your idea of big boys
maybe has some validity. I tried looking up some stuff, didn't find much (only how much fat and lean mass is lost, not correlates with success). I did find one study
http://www.wemjournal.org/article/PIIS1080603206702976/fulltext![Image](http://download.journals.elsevierhealth.com/images/journalimages/1080-6032/PIIS1080603206702976.fx4.lrg.jpg)
BMI is negatively associated with success in summiting Everest (albeit not significantly). I'm open to rebuttal (what do I know?), but at least provide some real information.
I agree its hard to keep bulk when conditioning for very high mountains. but people can get some bulk without too much effort (I'd like to see you reference to something that 85% of males can't!)
Carb loading the night before? eh no it's more than that. But you can do it the day before if you follow the correct protocol (some Aussies or Kiwis found a nice way to do it a few years ago). Sure that's mainly for day treks. Ask cyclists what they do for multiday events. Month long treks? I don't know. But that's an extreme case.