Muscle cramps, migraines, fatigue, nervousness - magnesium is essential for our body. Athletes, in particular, benefit from an adequate supply of this often-overlooked mineral. The author supports this with examples of Kenyan and Ethiopian runners, who are considered the best in the world. Unlike in our regions, they obtain their food from magnesium-rich soils. A deficiency in magnesium can, in the worst case, even lead to sudden cardiac death, with numerous examples provided in the book. Ana Maria Lajusticia Bergasa lists the foods richest in magnesium and offers valuable tips on how to use magnesium. She discusses the health benefits as well as the symptoms and dangers of magnesium deficiency. Anyone who is active in sports should read this book.