The book ("Amateur or professional?" - Guskov S.I.) tells about the change in the concepts of amateur and professional sports in the world, defines the amateur athlete and professional, tells about the penetration of business into sports, about the negative aspects of its commercialization and professionalization. Designed for the general reader and lecturers. Based on the data of fundamental biomedical sciences and the author's own research ("Harmony of Muscles" - A.N. Laputin), specific recommendations are given for those wishing to independently engage in athletic gymnastics with the aim of harmonic physical development and health promotion. Useful tips in this book will also find coaches and athletes. Designed for wide circles of readers, primarily young people.