More Doors, Less Fat
Insulin receptors are like doors that give you access to the muscle. When insulin comes by with a shipment of sugar, you better hope that you have enough doors to let it all go through or else it's going to be stored somewhere else (as fat).
So how do you increase the amount of doors/insulin receptors? You do this by building muscle. The more muscle you build the more insulin receptors you will have and the more sugar you will be able to store before you start storing fat.