Conor Heffernan traces the barbell back squat from a 19th‑century bodyweight drill to a loaded, multi‑purpose exercise central to strength training. He frames this evolution around three drivers: “equipment changes”, the “diversification of strength sports”, and “scientific communication” about safety and efficacy. Understanding this history, he argues, helps coaches avoid dogma about a single “correct” way to squat and instead program movements that fit a lifter’s goals and context.
Early patterns: gymnastics and “tippy‑toe” squats.
Modern fitness boomed with European gymnastics between 1790 and 1830—especially Jahn’s German “Turnverein” and Ling’s Swedish systems—implemented primarily in schools and militaries. These programs emphasized bodyweight drills; lower‑body work appeared, but the trunk and upper body dominated. Early squat instructions placed lifters “on the balls of the feet”, descending until thighs touched the heels while staying very upright—a technique seen in 19th‑century manuals and still common into the early 20th century.
First load: the dumbbell, then the barbell.
The first significant change was simply adding weight. As mass‑produced dumbbells appeared late in the 19th century, figures like Eugen Sandow popularized light, spring‑grip dumbbells for the public—often used while squatting on tiptoes. Commerce played a crucial role: Sandow marketed “safe” light weights that promised striking physiques, nudging the public toward loaded squats. The next leap came with “adjustable free weights”. Alan Calvert’s Milo Barbell Company (founded 1902) offered dumbbells and barbells that were first loaded with lead shot (metal pellets) and later “iron plates”, laying the foundation for progressive overload. A 1915 Milo pamphlet prescribed high‑rep “deep knee bends” with a “barbell on the back”, still balanced on tiptoes. A key constraint remained: balance—not strength—often limited load.
Modernizing technique: flat‑foot squats and racks.
In the 1920s, lifters began squatting “flat‑footed”, unlocking heavier loads and different muscular demands. Some feats—like H.P. Hansen’s 277‑lb × 65 reps (1899)—suggest earlier flat‑foot use, but broad adoption came later. In Europe, “deep knee bends” were already competitive by the “1910s–1920s”. In the United States, German strongman Henry “Milo” Steinborn became the pivotal evangelist. He not only popularized flat‑foot squatting but also demonstrated a way to get a heavy, unracked bar onto the back by “rocking” it from a vertical start into a deep squat and then standing—an approach widely imitated.
Two figures, Mark Berry and J.C. Hise, accelerated adoption. Berry’s “husky” program paired “high‑rep, heavy squats” (20–40 reps) with the now‑legendary “gallon of milk a day,” while Hise reported rapid weight gain and became a celebrity advocate. Their practical innovations included the “cambered bar” and, critically, early “squat racks/stands”—from boxes and tree branches to purpose‑built devices. By the 1940s, commercial racks (e.g., from York Barbell) were appearing in gyms. With flat feet, heavier loads, and a rack, the elements of the “modern” back squat were in place by mid‑century.
Competition and technology: weightlifting, powerlifting, bodybuilding.
From the 1900s to the 1950s, the strength world revolved around “Olympic weightlifting”. Cold War rivalry led to widespread “anabolic steroid” use after U.S. team physician John Ziegler developed Dianabol (1958), increasing athletes’ capacity and forcing the creation of drug‑tested vs untested federations. Meanwhile, the 1960s birthed “powerlifting”—making the squat a judged “competition lift” (with specific depth rules) rather than just an assistance exercise. This shift catalyzed technique debates (e.g., depth standards) and a wave of “supportive equipment”. Early experiments included “knee bandages”, even “tennis balls halved behind the knees” and “tight bedsheets” for body tension; by the 1970s, dedicated “knee wraps and squat suits” became common, alongside a proliferation of federations with differing equipment policies.
Another 1960s innovation driven by the “isometric craze” was the “power rack”, which enabled “isometric holds” at sticking points and novel partial‑range work. Though the isometric fad waned in the 1970s, the power rack remained a staple—an enabling technology for many squat variations and overload strategies. Footwear also evolved: “heeled weightlifting shoes” (often wooden heels) helped athletes sit deeper with a more upright torso, and later mass‑market models (e.g., Adidas with Tommy Kono) entered both weightlifting and powerlifting. For lifters with limited ankle mobility, such shoes facilitated “fuller range of motion”. In the 2000s, “CrossFit” popularized hybrid shoes, balancing lifting stability with general athletic movement.
“Bodybuilding” surged in the 1970s–80s—familiar to the public via “Pumping Iron”—and further normalized the back squat for “quadriceps hypertrophy” (iconically, Tom Platz). Simultaneously, “weight‑training machines” (e.g., Nautilus, from 1970 onward) entered commercial gyms, lowering user skill requirements and spawning machine‑based “squat” analogues (leg press, Smith machine, pendulum squat). Even where free‑weight back squats weren’t used, “squat‑like patterns” proliferated across the training landscape.
Science, safety, and messaging.
Through much of the early 20th century, heavy lifting met resistance from medicine and sport (fears of “muscle‑bound” athletes abounded). Entrepreneurs like Bob Hoffman and Joe Weider funded content and equipment, and figures such as Thomas DeLorme helped bring “progressive resistance” into rehab. By 1978 the NSCA was founded; soon, strength training became a staple in sport. Yet scientific messaging also “restricted” squatting at times: Karl Klein’s 1961 research asserted that “deep squats” destabilize knees, promoting “parallel/half‑squats” and “knees not past toes” rules. Later work (including an NSCA 1991 position paper) “debunked” his conclusions, but Klein’s influence persisted publicly for decades. More recent position statements confirm the “safety and value” of strength training (and squatting movements) for “youth” and “older adults”, further widening participation.
Practical takeaways
Heffernan closes by urging coaches to prioritize the “movement pattern” over any sacred exercise. The squat’s purpose has always shaped its form—high‑rep mass work vs low‑rep maximal lifts; weightlifting vs powerlifting vs bodybuilding; rehab vs general fitness. History shows “no single universal squat”, only context‑appropriate variations (high‑bar, low‑bar, front, goblet, Zercher, sissy, hack, and more). Recognizing how “commerce, competition, and communication” mold “truths” in training makes practitioners more critical, adaptable, and client‑centered.
- “b. Gymnastics.” The 19th‑century gymnastics boom (Jahn’s “Turnverein”, Ling’s Swedish system) popularized bodyweight squatting patterns.
- “b. Dumbbells.” The first big addition was adding weight with dumbbells (popularized by Sandow), before widespread barbell adoption.
- “a. Metal pellets.” Early adjustable implements were loaded with “lead shot” (metal pellets) before iron plates became standard.
- “c. 1910s.” “Deep knee bending” was a “competitive” practice in Germany by the “1910s–1920s”.
- “b. 1960s.” Powerlifting coalesced as a sport in the “1960s” (first national meet in 1964; AAU‑sanctioned meet in 1965).
- “c. Isometric holds.” The rise of the “power rack” in the 1960s enabled isometric holds and partial‑range work at sticking points.
- “b. Tennis balls cut in half behind the knees.” Early supportive “hacks” in the 1960s included halved tennis balls and tight bed‑sheet wrapping before modern wraps/suits.
- “a. Squat with a full range of motion.” Heeled weightlifting shoes helped lifters sit deeper with a more upright torso and assisted those with limited ankle mobility.
- “c. Iron Game sports.” Weightlifting, powerlifting, and bodybuilding are collectively referred to as “Iron Game” sports.
- “a. An exercise scientist.” “Karl Klein”, an exercise scientist, popularized joint‑specific safety concerns (arguing against deep squats) that influenced practice for decades.
Reference:
Heffernan C. The history and evolution of the back squat in the United States. Strength Cond J. 2025;47(3):269-278.