Magnesium glycinate is a highly bioavailable form of magnesium that supports the metabolism of macronutrients and energy production. While normal magnesium levels may lessen the perception of exertion during exercise, suboptimal levels can occur after the loss of fluids, including prolonged sweating, which can compromise performance. Magnesium is an essential bone matrix mineral that promotes healthy bone metabolism. A trial involving 2,038 older individuals indicated that higher intakes of magnesium were positively associated with bone mineralization for certain subjects. Magnesium also plays essential roles in maintaining healthy muscle contractile function. As magnesium regulates calcium channels, it may have an important role in controlling cramping. Several clinical trials have found that magnesium supports muscle function during intense exercise and helps to lessen nighttime leg cramps.