If you want to gain weight you could always eat fatty foods. But that wont do much for you if you are wanting to stay in shape. They might make you feel like you are up and ready for that one minute but all they are really going to do is bring you right back down. If you want to eat right and gain weight I guess some weight lifting would do some good. Not heavy weight lifting, because boxers are not weight lifters. You should practice your own sport. Make sense? lol