I am a college student, in Air Force ROTC, and I bike for 1.5-3.5 hours a day. My cardio and core strength are great, but I haven't found the motivation to build my upper body. I'm a skinny build, so it will take some work.
My question is: how will increased upper-body strength affect cycling, primarily all mountain and freeride type riding?
On top of HOW more upper body strength affects riding, which upper-body muscles will make the biggest difference?