I am a skinny, but really tall boy. I am 13 and am 5' 9" and have more growing to do. I have a question about mass gaining. I have been working a lot and am not seeing any result with mass but am with strength. I have heard that I should eat an extra 2,000 calories in order to gain size. I only see my arm muscles when I flex but don't when I don't flex. Any suggestion and can you do a video on mass gaining?
Eat enough protein, ideal is 1 g per kg or something like that, meat is good, you should never eat 2,000 extra calories, if your maintain level is 2,500 calories, what will you do to eat 4,500 calories? You might even gain fat depending on what you eat, but you can eat 200-500 calories more to kinda gain size, but be careful you might gain fat, do a research of bulking or calisthenics bulking.. You might need to wait for an answer from Chris because I'm really not sure about this :)