im very surprised at one of the responses thrown up on this thread!! genetically retarded... wanker.
anyway, try boosting your caloric intake by taking some form or gainer shake... i take Dymatize mega gainer, or if you really struggle, try super maga gainer also by dymatize.
i also noticed i really increased my gains when i jumped on 11-OXO, cycling it with a bottle of 6-OXO in this order... 2 bottles of 11-OXO(8 weeks roughly), 1 bottle of 6 OXO, 2 weeks off, repeat.
try having a gainer shake at 2 in the morning too...i noticed that helped me.