Professor Tim Noakes explains how industry-supported research created what would prove to be a fatal fable about athletes’ hydration needs during exercise. Noakes calls this fable the “Zero-Percent Dehydration Doctrine,” which led to a dangerous prescription that athletes drink as much as they can tolerate during exercise, regardless of exercise intensity, personal characteristics, or environment. Noakes outlines the methodology behind a study by Drs. Scott Montain and Edward Coyle that was integral to the creation of this prescription and explains why the researchers’ conclusions were flawed. He elucidates how so-called experts helped the sports drink industry, with the assistance of the ACSM, by creating a disease out of dehydration that conveniently could be treated with the consumption of its products, sometimes to disastrous effects.