Then again, some of us who weigh about 10 stones backpack with an 8x10. The camera, tripod and film holders and a lens put that at a little over 1 stone. But then I need to add water and other stuff, and the backpack weighs a few pounds as well. Not that bad, but if you go back 4 generations in my family, I get some of those Viking genes!
Bottom line is, you can get some pretty light setups if you plan accordingly, though you may have to make some sacrifices (like bring only one lens or two, and use your legs to get closer or farther away).