1. Building muscle has a lot to do with genetics.
If your parents are naturally thin or have a small body frame then most likely you will have the same traits. This doesn’t mean you have no chance of building a strong muscular body. It just means you are going to have to work hard.
2. Your metabolism has an effect on your size.
If you have difficulty gaining weight whether it’s fat or muscle, then you most likely have a fast metabolism. ..read more









