Gaining weight is all about calorie surplus. Eat more than you need now to say put on a set amount each week half a pound a week is possible without too much fat. Eat good quality meat spread out into, steak, chicken and fish, eggs and milk from dairy, plenty of carbs from rice, pasta and sweet potato, get your greens, asparagus and broc. For convenience have post workout shake and load some creatine, maybe a BCAA blend. Dont forget healthy fats, efa's virgin olive oil and flaxseed oil and eat some nuts. This will give you a clean bulk without to much fat.
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