If you are exercising regularly and strenuously you may require additional magnesium. Symptoms that indicate you may be deficient in magnesium include muscle cramps, muscle spasms, muscles that feel weak, feelings of fatigue and increased susceptibility to stress. Magnesium is a vital nutrient that is involved in many important processes, including energy production. This formula contains a high dose of Meta Mag, a patented form of magnesium that's highly absorbable. Endura Max contains vitamin C and taurine to help support your body against oxidative stress and damage of physical training. Taurine helps support healthy VO2 max and exercise time to exhaustion. Intense physical exercise can deplete magnesium levels. Magnesium deficiency symptoms include muscle cramps and spasms. Free from: gluten, wheat, dairy, lactose, eggs, yeast and salt. No added artificial flavoring, coloring or preservatives. Available in raspberry flavor and 260 g jar.