RE: Loosing Muscle Mass
I read on here, a while ago that you start losing muscle after about 2-3 weeks of not training. But if your diet goes to cr*p then yeah you'll lose muscle cuaase you body still needs fuel and needs protein for essentials. I guess this means producing blood cells and basic repair etc etc.
You can keep maintenence, so I'm told by having 100g protein per day (for a 200lb man) and doing light excerises to kee muscle stimulated. This'll slow the muscle-losing process down but won't hault it completely if you're out of proper training for weeks and weeks!