Susan Kleiner, PhD, RD, is a titan in sports nutrition. Her seminal research on male and female bodybuilders studied the nutritional needs of muscle building, power, and strength. Her expertise and research have expanded to hydration, and she is passionate about the nutritional needs of athletic women and girls. She is the founder and owner of the internationally recognized consulting firm High Performance Nutrition, LLC. The author of six other popular books, she has written numerous academic chapters and peer-reviewed scientific journal articles, as well as featured columns in all forms of media.

Kleiner has consulted with professional athletes and teams, Olympians, and elite athletes in countless sports. She is currently the high-performance nutritionist for the Seattle Storm and previously served that role for the Seattle Reign FC, the Seattle Seahawks, the Seattle Supersonics, the Miami Heat, the Cleveland Cavaliers, and the Cleveland Browns. She is a cofounder and fellow of the International Society of Sports Nutrition, a fellow of the American College of Nutrition, and a member of both the American College of Sports Medicine and the National Strength and Conditioning Association. Kleiner is a frequent invited speaker at national and international conferences and is a regular expert presence in online, print, and broadcast media.

Maggie Greenwood-Robinson, PhD, is a leading health and medical writer in the United States. She has authored or coauthored more than 65 books on nutrition, exercise, weight loss, psychological health, and other health-related issues, among them The Biggest Loser, a New York Times best seller that was the official diet and fitness book for NBC's hit reality show of the same name. Through her many collaborations, she has had 12 other New York Times best sellers, including 20/20 Thinking, Good Carbs vs. Bad Carbs, and Foods That Combat Cancer. Greenwood-Robinson has appeared on numerous television and radio shows, including Dr. Phil and NBC's Dateline. She has also written articles that have appeared in the magazines Shape, Let's Live, Great Life, American Health, Physical, Muscle & Fitness, and MuscleMag International. Greenwood-Robinson resides in Flower Mound, Texas.