K-Mag KG is a combination of the essential minerals potassium and magnesium with alpha-ketoglutaric acid (AKG). Potassium, magnesium, and AKG all have important roles in the Krebs energy production cycle, which produces ATP, the body's "energy currency." Without ATP, muscle contraction and athletic activity would be impossible. Potassium and magnesium are also necessary electrolytes, which play a crucial role in the contractility of heart and skeletal muscle.