Do I really have to sacrifice?
call me crazy and you wouldn't be the first.. i will be soon departing to climb mt. Kilimanjaro then everest. I know that climbing is a huge endurance challenge but I don't want to sacrifice muscle mass. am I going to lose mass with all of the long hikes and running? I'm not a body builder type but I'm built somewhat like a linebacker (used to be one) anyway to preserve strength and definition while cycling or marathon running?