"Donald T. Kirkendall is a lifelong soccer player, experienced coach, and member of both the FIFA Medical Assessment and Research Centre and the U.S. Soccer Sports Medicine Committee. William E. Garrett Jr., M.D., professor of orthopedic surgery at Duke University Medical Center, is chair of the U.S. Soccer Sports Medicine Committee and has served as team doctor for U.S. Soccer and the Duke University and University of North Carolina soccer teams. Kirkendall and Garrett have collaborated on six previous books, including "Exercise and Sport Science" and the ""U.S. Soccer Sports Medicine Book".