TheTour de Franceranks among the most popular sporting events in the world. It's also one of the most grueling. Tour cyclists burn3,000 to 4,000 caloriesper day, morethan marathon runners, and the race lasts 21 days. You have to be a world-class athlete to win the Tour once. In 1908, a Frenchman named Lucien Petit-Breton became the first man towin it twice. BelgianPhilippe Thyswon his third Tour in 1920. In 1964, FrenchmanJacques Anquetilcaptured his fifth. Five Tours is the record. It has stood for more than half a century. Three men have equaled it: BelgianEddy Merckxin 1974, FrenchmanBernard Hinaultin 1985 and SpaniardMiguel Induráinin 1995. Lance Armstrongshattered the record in 2004, winning his sixth and seventh Tours that year and the next. But his name was later stricken from the books. Now, the five-Tour record is vulnerable once more.Tadej "Pogi" Pogačar, a cyclist from Slovenia, won his fourth Tour in July. Pogačar is the youngest cyclist in history to win four Tours. "I mean, he's 26," saidPeter Joffre Nye, a cyclinghistorian. "Meaning that he's still young." Age matters in the Tour. Anquetil won his fifth Tour at age 30, Merckx at 29, Hinault at 30, Induráin at 31. BritonChris Froome, another four-time Tour winner, claimed his last victory at 32. Tour champions tend to reach their peak in their mid-20s, and to pass it sometime around 30. That means, in theory, Pogačar should have three or four more chances to win the Tour before his peak is past. "At age 26, he is physically in his prime," saidRon Kiefel, an American cyclist who rode in seven Tours. "Traditionally, that's between ages 26 to 32. If all goes well, he has many more years of amazing victories ahead." Still, there are good reasons why so few cyclists have won five Tours. One is the competition. The Tour draws the finest road cyclists in the world. Every Tour great has rivals who are nearly as good. Sometimes, the rival ultimately dethrones the champion. Hinault, the last French Tour winner, lost an epic battle for a sixth victory toGreg LeMond, a rising American star, who became America's first men's Tour winner in 1986. Pogačar's greatest rival isJonas Vingegaardof Denmark, a cyclist so talented that he has already beaten Pogačar twice. The Slovenian won in 2020 and 2021, the Dane in 2022 and 2023, the Slovenian in 2024 and 2025. "Vingegaard is only two years older," at 28, "so that rivalry will play out for many years to come," Kiefel said. Even so, the Pogačar who rode to victory in 2024 and 2025 looked all but invincible. His victory margin over Vingegaard in 2024 was more than six minutes. That's a lot: In an individual Tour stage, the leader is lucky to gain 30 seconds over his main rival. In 2025, Pogačar won four of 21 daily Tour stages. Vingegaard won none. Simple misfortune, too, could halt Pogačar's progress toward a fifth or sixth Tour title. Eddy Merckx lost the 1975 Tour, which would have been his sixth victory, after a fanpunched him in the kidney. Greg LeMond missed two Tours at his peak after nearly dying in a hunting accident. After alegendary comeback, he managed to win only two more: three in all. Crashes are routine in professional cycling. Abad crash in 2024may have cost Vingegaard his third Tour victory that year. One bad day in the mountains, where minutes can be gained or lost, has robbed many past Tour champions of a third, fourth or fifth victory. "During the Tour, you've got to be on every day for a month," saidMarianne Martin, an American who won the Tour de France Féminin in 1984. "You're not always the best. That's part of the whole sport." If Pogačar wants to win a fifth and sixth Tour, he will also need a great team behind him. The Tour is a team event: Seven cyclists, generally, ride in support of a leader. Pogačar has a great team now, the awkwardly named UAE Team Emirates-XRG. In the 2025 Tour, Pogačar's team boasted sufficient talent and discipline to support him in the mountains, where the top contenders often need the most help. At moments when the lead group of riders dwindled to 20 or fewer, Pogačar usually had teammates pedaling in front of him. "His team is the only team that has its s—t together, in terms of supporting its leader," saidGeorge Mount, a retired rider who was the first American cyclist to successfully compete in Europe after World War II. Two or three other cyclists at the 2025 Tour were nearly as good as Pogačar, including Vingegaard and 25-year-oldRemco Evenepoelof Belgium. Most of Pogačar's rivals rode for weaker teams. Vingegaard's teammateseffectively abandoned himwhen he crashed on a stage of the 2025 Tour, further evidence of disarray. If Vingegaard stays with his team in 2026, "and they get their act together, then it's a different story," Mount said. "It will be a more competitive thing." Mount gives Pogačar a 50-50 chance of breaking the five-Tour record. He's alreadythe favoriteto win in 2026. After that, who knows? "It's often said that you can't win [the Tour] in one day, but you can lose it in one day," said Nye, the cycling historian. "It could be bad food, or it could be a bad crash. Cyclists, like all professional athletes, are vulnerable." Daniel de Visé covers personal finance for USA Today.He is also author ofThe Comeback:Greg LeMond, the True King of American Cycling, and a Legendary Tour de France. This article originally appeared on USA TODAY:Tour de France record has stood for 61 years. It may soon fall.