The book offers a variety of exercises for training concentration, perception, memory, and information retrieval. Fun and enjoyment in thinking are at the forefront. This mental fitness training for our gray matter is not limited to rote memorization or solving crossword puzzles. Instead, it focuses on thinking critically, considering different perspectives, experiencing new things, questioning the familiar, and re-evaluating the usual. Success, self-confidence, and competence are not a matter of predisposition, but rather the result of actively training our brains. Those who regularly exercise their minds will not only become smarter but also improve their concentration and prevent forgetfulness. The best health prevention begins not only with physical fitness but also with mental fitness.