Proteins are an important group of chemicals that fulfil various functions in your body. One of these functions is the building function, which is responsible for creating an active body mass. Proteins consist of amino acids, number of which are essential. It is necessary to obtain these essential amino acids from food regularly.
To sustain a muscle mass, you need to choose a quality protein source in the minimal amount of 0.5 g for one kilogram of your weight per day. For people who are not active, 0.7 - 1 g for one kilogram of their body weight is enough. For active athletes, the optimal protein intake should be in the range of 1.2 g to 1.6 g for a kilogram of their body weight. If your main goal is to increase your muscle mass, you can increase your intake to 0.7 g for a kilogram per day.