Book excerpt: Suitable both for people setting out to be instructors and for seasoned professionals, this resource provides a guide to the scientific, instructional and professional knowledge required of group fitness instructors. Chapters include: exercise physiology; fundamentals of anatomy; biomechanics and applied kinesiology; nutrition and weight control; health screening; fitness testing and aerobic programming; teaching an aerobic class; special populations and health concerns; exercise and pregnancy; musculoskeletal injuries; emergency procedures; and legal and professional responsibilities.