Harley Pasternak holds a Masters of Science in Exercise Physiology and Nutritional Sciences from the University of Toronto, and an Honors Degree in Kinesiology from the University of Western Ontario. He is also certified by the American College of Sports Medicine and the Canadian Society of Exercise Physiology.

Harley is a popular speaker throughout the United States, Canada, Mexico, and Brazil for such organizations as: The National Strength and Conditioning Association (NSCA), Town Sports International, International Health and Racquetball Club Association (IHRSA), Club Industry, Proctor & Gamble (ThermaCare, Oral B), Unilever (Slim-Fast), Precor, Department of National Defense, The Canadian Society of Exercise Physiology, the Canadian Health Food Association, Canadian Academy of Sports Medicine, Can Fit Pro, University of Toronto, and York University.

Harley's first book, 5-Factor Fitness (Putnam, 2005) was a number one top seller in its category at Barnes & Noble and Amazon.com. His highly anticipated follow-up book, 5-Factor Diet (Meredith, 2006), made the New York Times Bestseller list. In his capacity as a fitness and nutrition specialist, Harley has appeared on The Oprah Winfrey Show, The Tyra Banks Show, Access Hollywood, Extra, VH1, E!, The Jane Pauley Show, and America's Next Top Model as well as made multiple appearances on The Today Show. In addition, Harley and 5-Factor have had great print coverage in such publications as Star,Us Weekly, In Touch, Shape, Woman's World, People, Glamour, Elle, Allure, Men's Health, Jane, Fitness, Seventeen, Self, Marie Claire, Teen People, the New York Post, the LA Times, and the Washington Post, among other publications.