The result, of course, was disaster

In 1904, the Heidelberg chemist Wilhelm Weichardt made a sensational announcement. He promised a utopia in which men would never grow weary, but would be transformed into industrious and tireless machines. Weichardt thought that fatigue was caused by the accumulation of toxins in the blood, and he harvested a concentrated version of this poison from rats that he drove to death by strenuous exercise. As the toxins built up, he observed, the rats descended into a kind of "narcosis" or "stupor," before slowing to a "complete standstill." In his laboratory, Weichardt worked on an antibody. He called the resulting miracle drug—his vaccine against fatigue—antikenotoxin.

In The Human Motor: Energy, Fatigue, and the Origins of Modernity (1990), Anson Rabinbach explains how, after 1870, the religious discourse against acedia or sloth was taken up and replaced by the burgeoning scientific study of fatigue. Fatigue, Rabinbach argues, was considered both a physical and moral disorder: it "replaced the traditional emphasis on idleness as the paramount cause of resistance to work. Its ubiquity was evidence of the body’s stubborn subversion of modernity." In the eighteenth century, idleness had been presented by artists such as Hogarth as the antithesis of industry; in the nineteenth century, fatigue was considered a similar failure—it represented the refusal of the body and mind to keep up with the demands of modern labor. Maurice Keim, one of the first of these nineteenth-century theorists, wrote that "we flee [fatigue] by instinct, it is responsible for our sloth and makes us desire inaction."

more from Cabinet here.