Mineral supplements, protein and amino acids are very important in a diet, for those who are physically active. They help to replenish the minerals, or fluids, lost through sweating and also their main role in the body is for growth, repair and maintenance of body cells and tissues, such as muscle.
The recommendations for daily protein intake are set equally for both endurance training and resistance training athletes, so higher intakes are not recommended even for those exclusively trying to build muscle. Mineral supplements will not be used for muscle building but just used as energy, avoiding excessive fatigue on the body.
An unmonitored or excessive consumption of dietary supplements can be serious. It may occur some undesirable side effects on metabolism: creatine, for example, is a substance that can strain the kidneys.