Michael Phelps
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Michael Phelps is the most decorated Olympian of all time with 28 medals, including 23 golds, and he's undoubtedly one of the best swimmers in history. Given how much he's accomplished, it's natural to wonder how far his abilities could take him. Could he swim 100 miles from the middle of the ocean back to shore? 

That's the question rapper Young Thug asked while incarcerated in Atlanta's Fulton County Jail -- he's reportedly been charged in a "wide-ranging" RICO case and is awaiting trial -- on a random summer afternoon, and it's one even Phelps thinks is worth diving into.

There is no doubt Phelps is a fast swimmer. When he broke the world record in the 100-meter butterfly race at the 2009 World Championships, he registered an impressive speed of just over 5.5 miles an hour. However, 100 meters (about .06 miles) is a much shorter distance than 100 miles.

This would technically not be Phelps' first ocean challenge. In 2017, he was featured on Shark Week in an experiment to see how his speed compares to a shark. Phelps got equipped with a suit that mimicked the skin of a great white shark and a special fin to help increase his speed and somewhat even out the field.  

Needless to say, Phelps is not faster than a great white shark, but he is still a very fast human. Speed could certainly help, but it would not be all he needs for a 100-mile journey -- endurance would be crucial. Fortunately for him, there is a whole area in the sport of swimming for challenges like the one Young Thug is suggesting.

Marathon swimmers do open water distances of at least 10 kilometers, the equivalent of 6.21 miles. They are allowed a bathing suit, a swim cap, ear and nose plugs, goggles, skin lubricant, food and an escort boat for safety.

Because this imaginary scenario (at least for now) is serious business, Phelps talked to his longtime coach Bob Bowman about how long the challenge could take. They came up with somewhere around 50 hours, although Phelps believes it would be "unpleasant." Based on Phelps' skill level and other swimmers' experiences, that number is a pretty good educated guess.

According to the Guinness World Records, Spanish swimmer Pablo Fernandez broke the record for longest distance ocean swim on July 19-20, 2021, traveling a distance of 155.34 miles in 26 hours, 36 minutes and 18 seconds. Fernandez did not use fins or hand paddles, but he was strategic and used the fast-moving Gulf Stream. His expertise mixed with good water and weather conditions were the perfect formula for success. 

Per NOAA's National Ocean Service, the Gulf Stream is the fastest current near the surface and can reach a maximum speed of about 5.6 mph, which is slightly faster than Phelps' 2009 100-meter butterfly record. Going that route could help Phelps accomplish the challenge in well under 50 hours, but the ocean conditions would have to be ideal. 

Phelps could also gain confidence by looking at someone with a somewhat similar background to him. On June 30, 2021, former Olympic 400m swimmer Neil Agius completed a 126.3 km (around 78.48 miles) journey from Italy to Malta in over 52 hours. That was the longest unassisted and continuous current-neutral swim in history. Agius competed in the 2004 Olympics in Athens and finished 46th in the 400m freestyle event. Phelps did not participate in that particular race, but he left Athens with six gold medals and two bronze.

There is technically no reason as to why Phelps couldn't attempt the 100-mile challenge, but no matter how he chooses to approach it, there would be a lot of training involved. According to marathon swimmer Melodee Nugent, it would take at least a few months to prepare.

"When training for your marathon swim, you should be swimming the distance of that event in a week for at least a few months before the actual event," she wrote in an explainer on how to become a marathon swimmer. 

This might be a daunting task to the average person, but Phelps is no stranger to intense training. When he was competing, he reportedly trained almost six hours a day, 365 days a year.

As of now, there doesn't seem to be actual plans for Phelps to attempt Young Thug's challenge. But if Phelps does decide to go for it, it's probably a good idea to start training now -- and perhaps borrow the Shark Week suit and fin to get the extra edge.