Where does eating come in? If you want to gain weight you need to eat more calories!! The trick to gaining muscle and not fat is ensuring that when you increase calories you maintain BALANCE in your diet. The best way to add muscle mass is to stick to a healthy diet containing 55-65% of calories from carbohydrates, 10-15% of calories from protein and less than 30% of calories from fats.
Here are some tips and tricks for adding calories in healthy way to build muscle and avoid unwanted fat: