The seventh-inning stretch, when fans rise from their seats for a brief break after the top of that inning is complete, is as much a part of Major League Baseball as beer at ballparks and booing umpires. But the origins of the American tradition, which may date to 1869, are as murky as the ingredients in a hot dog.

The most well-known origin story involves William Howard Taft, who served as 27th U.S. president from 1909-1913. At an opening-day game in Washington against the Philadelphia Athletics on April 14, 1910, he threw out the first pitch before taking his seat in a box near the field. In the middle of the seventh inning, the 300-pound Taft—"a lover of baseball," according to a newspaper account—stood up to stretch his legs. The crowd, thinking the president was leaving, rose out of respect.

The Taft story is part of the "mythology" of the seventh-inning stretch, says author Chris Epting, who has written more than 30 books about sports and pop culture history. He likens tales of the origins of the seventh-inning stretch to stories about Babe Ruth's famous "Called Shot Home Run" in the 1932 World Series. Did Ruth really point to center field at Wrigley Field before he hit the homer? No one really knows for certain.

The second well-known seventh-inning stretch tale involves Brother Jasper, the first baseball coach at Manhattan College, and a game on a hot day in 1882. Jasper, who also was the Catholic school's Prefect of Discipline, noticed spectators were rambunctious. So, he called a timeout during the seventh inning and instructed fans to stretch their legs. Jasper's seventh-inning respite eventually was adopted by the New York Giants, who played exhibitions against Manhattan College.

Both these origin stories were trumped by the discovery of a letter written in 1869 by Harry Wright, the manager of the Cincinnati Red Stockings, the first professional baseball team. "The spectators all arise between halves of the seventh inning, extend their legs and arms and sometimes walk about," wrote Wright. “In so doing they enjoy the relief afforded by relaxation from a long posture on hard benches.”

Wright’s letter may be documented proof that the stretch predates Brother Jasper and President Taft, but it brings us no closer to the origin of the tradition. One theory is it stems from another American tradition: commerce. The break between innings gave fans time to buy a snack or a refreshment without missing any action.

Early 20th-century newspapers were peppered with "seventh-inning stretch" references.

In 1914, a cigar company advertised its product as the "choice of 50,000 Philadelphia 'Seventh-Inning Stretchers.' "

During World War I, the tradition caused consternation among law enforcement at a game between U.S. servicemen in England. "When the hundreds of American spectators gave that old familiar seventh inning stretch," a newspaper reported in May 1918, "the London policemen on duty at the ball park were startled and feared there was trouble."

In 1919, a newspaper chastised fans who didn't stand for the seventh-inning stretch: "It is almost as bad form to stay in your seat then as it is when the national anthem is being played or the country's colors are passing in review."

The same paper explained why women stood for during the brief break: "That suit she has on is the latest word in spring aparel [sic]. She must show it and will never get a better chance." Fans of the era frequently dressed up for games.

In 1925, a Florida newspaper observed: "No nation today performs a rite so punctiliously or in such overwhelming numbers as the rite of the seventh-inning stretch, observed six months in the year in every American baseball park."

And, in 1927, the Galveston (Texas) Daily News reported: "It Is a custom throughout the baseball world to rise and cheer the seventh inning, particularly if the home club is behind. We were surprised that this was not observed Sunday when the Cokes came to the bat two runs to the bad in seventh. Nothing encourages players more to emerge from the rear than the seventh inning stretch."

Whenever the seventh-inning stretch was conceived, it eventually became part of the ballpark experience. And, in the mid-1970s, Chicago’s legendary baseball broadcaster Harry Caray inadvertently added the tradition's soundtrack, "Take Me Out to the Ball Game."

Widely considered baseball's national anthem, "Take Me Out to the Ball Game" was written by Jack Norworth in 1908. The Tin Pan Alley songwriter was inspired to write the lyrics when he saw an advertisement for baseball while riding the subway to the Polo Grounds, home field of the New York Giants. (Today it's one of the three most popular songs in the United States, behind “The Star-Spangled Banner” and “Happy Birthday.”)

After the top of the seventh inning, Caray sang "Take Me Out to The Ballgame" in the broadcast booth while he was broadcaster for the White Sox from 1971-81. He didn't know it at the time, but the team's flamboyant owner, Bill Veeck, secretly placed a public-address microphone in the booth so the crowd could hear the broadcaster's rendition. Caray eventually picked up the mic and belted out the tune at every game at Comiskey Park. A tradition was born.

From 1982-1997, Caray sang "Take Me Out to The Ballgame" while he was Cubs' broadcaster at Wrigley Field. Other teams picked it up, and soon it was played in every MLB ballpark in between the top and bottom of the seventh inning.

Perhaps even that "lover of baseball," William Howard Taft, would approve.

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