Meet the sport beloved by America's 31st president and CrossFit

President Herbert Hoover was looking a little thick through the waist when he met with White House physician Joel T. Boone on just his second day in the White House in 1929. The consequences of 54 years as a sedentary, cigar-smoking politician who preferred driving to walking and was "always snacking" had become clear. In 1931 even the New York Times noticed that the president "had come to weigh more than he should."

The president's physician got creative. He invented an entirely new sport, just for the President.

That sport was Hooverball, a game where a weighted medicine ball – usually about 6 pounds – is thrown over the net. The scoring works like tennis, but in practice, the game looks more like volleyball, though you are supposed to catch the medicine ball, not volley it. Hooverball can be played with just four players, two on each side of the net, but the game is more functional with three or four on each side.

Boone hoped the game would help President Hoover slim down. It worked. The New York Times reported that Hoover dropped 25 pounds and saw his muscles "harden" as he committed to the daily ritual of 7 a.m. Hooverball games at the White House. The President's playing style was described as "lusty."

Hooverball fell out of favor after Hoover's term ended (his successor President Franklin Delano Roosevelt had polio and preferred swimming). Nearly 100 years later, however, the sport resurged, Matthew Schaefer, an archivist at the Herbert Hoover Presidential Library in Iowa, explains.

The resurgence began in 1988 when the Library organized the first National Championship of what they deemed "America's forgotten sport" in a contemporaneous New York Times article. The resurgence was further propelled by the endorsement of some unexpected Hooverball enthusiasts:

"Cross-fitters loved it because it took so little equipment and provided a very demanding workout," Shaefer tells Inverse.

What makes Hooverball a sport? – Many have fallen into the trap of believing that Hooverball is easy. As the author of the 1931 New York Times piece notes it "is not pink tea stuff."

The intensity of Hooverball places it firmly into sports territory. Most beginners vastly underestimate how hard it is to catch a six-pound medicine ball flung with full force, says Schaefer. To count, a ball caught on the front half of the court must be returned to the back half of the opponents' court (if it drops, a point is scored).

That means that Hooverball players are really going after it.

"It will knock you over if you don't brace," Schaefer says. He's only played once, but notes that "I quickly learned it was no game for old men."

In its heyday, Hooverball also garnered enough of a following to elevate it from the President's personal workout routine into a bonafide sport. Schaefer estimates that at least 100 men played Hoover ball at least once during Hoover's term, including cabinet members, friends of the President, secretaries (but only men), and reporters.

Those that played regularly became known as members of "The Medicine Cabinet."

As one Medicine Cabinet member and Secretary of the Interior Ray Lyman Wilbur wrote "Only absence from Washington kept us away."

The Michael Jordan of Hooverball – If you ask Schaefer, two players ascended to Hooverball supremacy: Secretary of the Interior Ray Lyman Wilbur and Supreme Court Justice Harlan Stone.

Wilbur was "wiry and strong," says Schaefer. At 6 feet, four inches tall, The New York Times reported that he had a "peculiar advantage" because he could volley the ball from far above the net, using that height to his advantage.

Harlan on the other hand was a more traditional athlete. A former Columbia football player, who weighed around 220 pounds, he was described as "deep-chested." As the New York Times writer observed:

"When he hurls them, they stay hurled."

The spirit of Hooverball – Hoover was bored by calisthenics and too busy to make the walk down to the fishing hole or go our for a ride, even though he knew the importance of exercise.

"Once the day's work starts there is little chance to walk, to ride, or to take part in a game," Hoover wrote. "Taking walks or rides early in the morning is a lonesome business, and the inevitable secret service guard when the president leaves the White House grounds is not enlivening company."

Hooverball was created to be an alternative for a President who was unenthused by workouts. It's not that Hoover hated sports. When asked by The New York Times if he actually did enjoy exercise, Hoover said that he did "in the right setting."

Hooverball was about creating the right setting – a way to make working out feel fun and less like prescribed medicine.

That spirit is perhaps even more relatable now than it was in the 1930s, especially because exercise is so often prescribed as treatment. The World Health Organization advises that adults get 150 minutes of moderate exercise per day to stave off disease.

"It will knock you over if you don't brace."

But that doesn't mean exercise has to include grueling workouts or even classic sports. Our definition of what counts as exercise has continued to expand. The Compendium of Physical Activity, a document that allows epidemiologists to track the energy expenditure of different physical activities, includes entries from arcade games to the Eskimo Olympics in the "sports" category.

Schaefer thinks that Hooverball has resurged in this climate, buoyed by the fact that it's a strangely good workout and the fact that we're increasingly open to exercising in weird ways. In 2015, Hooverball was included in Men's Journal's piece "14 World Championships anyone can win," below the likes of lawnmower racing and stone skipping.

There's no doubt that this attention helped boost Hooverball's profile, even though Schaefer disagrees that anyone can win it. That's evidenced by the community that has embraced the sport the most.

The clear non-traditional exercise enthusiasts that championed Hooverball in the 21st century were CrossFitters, says Schaefer. "The 21st-century revival took off when the founder of CrossFit incorporated it into his 'Workout of the Day,'" he says.

Shortly after CrossFit founder Greg Glassman featured Hooverball, he received a note from a U.S. Marine who said he had tried the sport with a 12-pound medicine ball. After 55 minutes, the team of marines was "wiped out."

Glassman went on to included Hooverball in an entry in The CrossFit Journal, though he notes that as much as CrossFitters love the sport, they do put their own distinctly insane spin on it.

"We had to give it that CrossFit flavor so we played on sand with a twenty-pound ball and an aggressive ball snapping Pitbull," Glassman writes. "It was indeed hard; everyone was tired, and one well known Brazilian Jiu-jitsu Black Belt got bit."

It's pretty clear that snapping Pitbulls are probably not what Boone had in mind when he created a sport for President Hoover. Still, at least they captured some of the sport's initial spirit. Hooverball is an exercise for people who reject traditional exercise, and rather play a wacky game.

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