Michael Phelps swims fast, but not fast enough to beat Uncle Sam, who awaits him at the finish line each time he wins a medal. His total income tax bill for the 2016 Games? Up to about $55,000 for his five golds and one silver.

Olympic athletes who bring home medals also bring home cash — $25,000 for gold, $15,000 for silver and $10,000 for bronze — paid for by the United States Olympic Committee. Like any prize winner, from a jackpot hitter to a Nobel Prize recipient, the athletes are taxed because Olympic medals and cash bonuses are considered income, said Steven Gill, associate professor of accounting at San Diego State University.

The maximum possible "victory tax" on the bonus for each gold medal, using the top tax rate of 39.6% for the nation's highest earners, is $9,900, according to Americans for Tax Reform. For silver, it's $5,940, and for bronze it's $3,960. Athletes in lower tax brackets would owe less — and keep in mind that some or all of their massive training expenses would likely be deductible, whether they treat their sport as a business or a hobby.

The medals themselves are taxed, too, but they're not as valuable as their shiny goodness may appear. Based on the commodity prices of the metals involved, gold is worth in the neighborhood of $600, silver about $300 and bronze next to nothing. What they'd go for on the open market is much higher, easily $10,000 or more, but that's not a factor unless an athlete sells or otherwise disposes of the medal, according to tax expert Blake Christian, partner at Holthouse Carlin & Van Trigt.

Congress has tried to give Olympic athletes a tax break. In 2012, Sen. Marco Rubio, R-Fla., introduced a bill to shield medals and bonuses from Uncle Sam, but it died. “We can all agree that these Olympians who dedicate their lives to athletic excellence should not be punished when they achieve it,” Rubio said in a statement then.

This year, Sens. John Thune, R-S.D., and Chuck Schumer, D-N.Y., sponsored a similar bill to eliminate taxes on Olympic and Paralympic athletes. The bill passed the Senate in July. “Our Olympian and Paralympic athletes should be worried about breaking world records, not breaking the bank, when they earn a medal,” Schumer said in a statement last week.

As for Phelps and his maximum Olympic tax bill of $55,440, don't worry. He probably won't have a hard time paying up. His net worth is about $55 million, according to Celebrity Net Worth.