Supplement indicated for athletes: Magnesium contributes to the maintenance of muscles and bones in normal conditions. Vitamin B6 helps reduce tiredness and fatigue. Vitamin B1 helps normal energy metabolism. Vitamin D3 contributes to the normal absorption and utilization of calcium and phosphorus. Lemon flavor effervescent tablets. Instructions for use: Take 1 tablet per day during periods of high intensity activity. Dissolve in a glass of water (150 ml) and drink once it has stopped bubbling.