Why Lifting Heavy Was Called Dangerous

In 1985 the American College of Obstetricians and Gynecologists issued its first formal guidance on exercise in pregnancy. It told women to keep their heart rate under 140 beats per minute and to stop strenuous activity after fifteen minutes. Those numbers were not measured. They came from a panel of obstetricians, none of whom had any training in exercise physiology, and one of the authors later admitted the guidance rested on "common sense" (00:01, 00:24). The heart rate ceiling disappeared from the guideline nine years later. The habit that produced it did not.

That habit, inventing a warning first and finding (or not finding) evidence later, is the real subject traced by physician Jordan Feigenbaum on the Barbell Medicine Podcast. He follows it back roughly twenty-five hundred years, through Greek gymnasiums and Roman gladiator schools, where the physician Galen defined exercise as movement vigorous enough to change breathing, a standard that still works today (04:38). Across that whole stretch, nobody wrote down that lifting heavy things would hurt the knees, stunt a child, or endanger a pregnancy. The warnings are a much newer invention, and in the United States they begin with a very specific person.

In 1854 a five-foot, hundred-pound Harvard student named George Barker Winship tried a coin-operated strength tester on a street in Rochester and pulled 420 pounds. He went home, dug a hole in his yard, buried a barrel of rocks, and built his own machine. Over the next several years he worked his way from 700 pounds to 2,007 pounds, eventually carving a wooden yoke for his shoulders to handle the load (06:55, 08:04). He wrote the line that became the slogan of the whole movement:

"Strength is health." — George Barker Winship, quoted by Jordan Feigenbaum [08:50]

"He who does the work of the grade suited to a truck horse is far more likely to acquire the heavy and ponderous ways of that worthy animal." — William Blaikie, quoted by Jordan Feigenbaum [11:24]

The "muscle-bound" idea calcified for decades until a 1940 showdown at Springfield College, then the country's leading physical-education school. Its chief physiologist, Peter Karpovich, had been calling bodybuilders "quacks," so an undergraduate invited York Barbell's Bob Hoffman to bring two elite lifters to campus. Karpovich asked a lifter to scratch his own back between the shoulder blades, expecting him to fail. He did it easily, then dropped into a full split. Karpovich later admitted,

"The audience roared with laughter at my expense." — Peter Karpovich, quoted by Jordan Feigenbaum [24:48]

How a myth moves from magazine to military

In 1961 a University of Texas professor named Carl Klein reported that lifters who squatted below parallel had looser knee ligaments, using an instrument he built himself that was never validated for the purpose (26:38). Sports Illustrated ran the story in 1962, and every branch of the American military dropped the deep squat from training. It took more than three decades for the correction to arrive: a 1989 study of 100 college students found no consistent effect on knee stability from full squats, and a 1994 study of 32 professional football players found the same after 21 weeks of heavy squatting (27:48, 28:13). The one physician who pushed decisively in the other direction during this era was Thomas DeLorme, who as an army doctor in 1944 had soldiers with knee injuries lift the heaviest weight they could handle for ten reps, repeated across multiple sets. Recovery that used to take six to nine months took weeks (34:42, 35:28). His method was so effective the Army mandated it across its hospital system in 1945. Three years later he cut the volume to three sets of ten, and, worried that doctors would balk at the word "heavy," his wife Eleanor suggested renaming it "progressive resistance exercise" (36:08). The heaviness got quietly edited out of the name, and a generation of coaches inherited a softened version of a protocol built to handle soldiers' torn knees.

Women got a version of the warning that has aged even worse. In 1912 Harvard's head of physical education, Dudley Sargent, wrote that heavy training would make a woman's figure "more masculine," prescribing lighter apparatus to protect her femininity (45:58, 46:20). Sixty years on, Nautilus inventor Arthur Jones insisted women could not build large muscles "if her life depended on it," while in the same breath marketing a machine to shape the thighs women supposedly did not want bigger (46:45, 47:07). A study finally tested the claim directly in the late 1980s: men and women training the same program for sixteen weeks gained the same relative muscle size, about 20 percent, with men simply adding more in absolute terms because male puberty builds a larger starting base (47:49). Few people read that paper. What people did see, through the 1970s and 80s, was women's sport records falling fast, which turned out to be a doping era rather than a training secret (48:09, 48:34), plus a selection effect: unusually muscular, strong women gravitate toward strength sports, the same way unusually tall people gravitate toward basketball, rather than the sport creating the trait (50:11). Institutions lagged accordingly. Men's weightlifting debuted at the first modern Olympics in 1896; women's weightlifting did not arrive until 2000 (52:21, 52:43).

The warning that is still here

Pregnancy carried its own folklore: that exercise would steal blood from the uterus and starve the fetus, a theory a later review notes was "never proven" (53:52, 54:12). A 1949 federal bulletin allowed housework, gardening, and a daily mile-long walk, but not sport (54:19). Textbooks into the 1960s warned against "violent exercise," their examples being tennis, horseback riding, swimming, and cycling (54:19). The 1985 heart-rate guidance that opened this story was simply the medicalized version of the same instinct. Today's official opinion says physical activity in pregnancy is "safe and desirable" and that fears about miscarriage or poor growth have not been substantiated, yet one study found 91 percent of pregnant women who got any counseling at all were never told how often, how hard, or what kind of exercise to do (55:51). A 2025 study put ten pregnant women through barbell squats, bench presses, and deadlifts at 90 percent of a ten-rep max, including a set performed with the Valsalva maneuver, meaning holding the breath against a closed throat under load, which is exactly what old guidelines feared. Fetal heart rate did not drop (56:21, 56:48).

Feigenbaum's closing point is less about lifting than about how caution gets manufactured. Smoking was linked to lung cancer because someone studied it. High blood pressure was linked to artery damage because someone studied that too. The century of warnings against lifting heavy was not built that way:

"None of these warnings were built that way. They were all based on vibes." — Jordan Feigenbaum [58:10]