Frédéric Delavier is a gifted artist with an exceptional knowledge of human anatomy. He studied morphology and anatomy for five years at the prestigious École des Beaux-Arts in Paris and studied dissection for three years at the Paris Faculté de Médecine.

The former editor in chief of the French magazine PowerMag, Delavier is currently a journalist for the French magazine Le Monde du Muscle and a contributor to several other muscle publications, including Men's Health Germany. He is the author of the best-selling Strength Training Anatomy, Women's Strength Training Anatomy, The Strength Training Anatomy Workout, The Strength Training Anatomy Workout II, Delavier's Core Training Anatomy, and Delavier's Stretching Anatomy.

Delavier won the French powerlifting title in 1988 and makes annual presentations on the sport applications of biomechanics at conferences in Switzerland. His teaching efforts have earned him the Grand Prix de Techniques et de Pédagogie Sportive. Delavier lives in Paris, France.

Michael Gundill has written 13 books on strength training, sport nutrition, and health. He coauthored The Strength Training Anatomy Workout, The Strength Training Anatomy Workout II, Delavier's Core Training Anatomy, and Delavier's Stretching Anatomy. His books have been translated into multiple languages, and he has written over 500 articles for bodybuilding and fitness magazines worldwide, including Iron Man and Dirty Dieting. In 1998 he won the Article of the Year Award at the Fourth Academy of Bodybuilding Fitness & Sports Awards in California.

Gundill started weightlifting in 1983 in order to improve his rowing performance. Most of his training years were spent completing specific lifting programs in his home. As he gained muscle and refined his program, he began to learn more about physiology, anatomy, and biomechanics and started studying those subjects in medical journals. Since 1995 he has been writing about his discoveries in various bodybuilding and fitness magazines all over the world.