So I'm back to weight training after quite a few years but even back then I never really ended up big so here goes, I train at home on a monday(chest n back). Wednesday (legs). Friday (shoulders n arms). Then start the sequence again Sunday, is doing those muscle groups once a week enough to create growth. And i dont eat a hell of alot but how important is it to eat alot, I'm not skinny and do have plenty of fat lol but I want to gain size but don't want to really gain any more fat I'm 5ft 9 and around 13 stone...thanks.