Zechstein Magnesium Gel supports the massage of tense muscles. Magnesium absorption via the gastrointestinal tract is subject to complicated biochemical resorption processes in which only around 10-20% can be absorbed. Magnesium applied externally bypasses the gastrointestinal tract and acts directly on the cells. Application: Apply Zechstein Magnesium Gel and massage in gently for a few minutes. Leave the gel on the skin for at least 15 minutes and then rinse off with warm water. Use for acute cramps: For acute cramps, Zechstein Magnesium Gel is applied directly to the painful area and rubbed in. This usually relieves the cramp within a few seconds.