As men entered World War I, women were called upon to perform traditionally male roles involving more physical labor and brawn. The British Health of Munition Workers Committee found:

“that, compared with man, woman has less strength, less endurance; that she can undergo neither such long hours nor such long periods of labor; that she cannot stand the strain of night work; that her body, physiologically different from man’s, is subject to ‘certain ailments and forms of physical disability’ that are ‘readily caused or at least accentuated’ by various forms of body activity, and that these ailments are ‘far-reaching in effect’; that the lifting and carrying of heavy weights, ‘all sudden, violent, or physically unsuitable movements in the operating of machines,’ and prolonged standing, are ‘highly provocative causes of trouble to women and girls.’”

Anybody who still claims that men have more stamina and women need more “days off” should read the news this week. Ivanka Trump had to fill in for her father at an event that he dropped out from, citing “exhaustion.”

Man’s Labor the Best, British Committee Decides; Woman Handicapped: The Frailer Sex Lacks Nothing in Patriotism, But Needs More “Days Off” — Endurance in Munition Plants

From Sunday, May 27, 1917