As he later revealed, Phelps was reacting to le Clos’s bizarre tactic of shadowboxing in front of his rival ahead of the race.
“Everyone has their own race strategy. If that’s his, that’s his,” Phelps told NBC’s Michelle Tafoya of le Clos, explaining that he was unfazed by his competitor’s tactic.
That explains the why, but what about the how? As any experienced mean mugger knows, a true game face can be made or broken by the soundtrack that accompanies it. So what was playing through Phelps’ headphones when he displayed that penetrating scowl?
Eminem, of course.
Phelps revealed his go-to warm-up music of the 2016 Games during a Facebook Live chat with PEOPLE on Tuesday.
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“I went back to 2003 and 2004 Eminem,” the 24-time gold medalist said of his pre-race music of choice.
Phelps added that Lil Wayne, Steve Aoki, Nero and Skrillex also made his pump-up playlist.
“I was just trying to really get going and really get amped right before I would walk out and [the music] helped a lot – I was sometimes tired,” he continued.
With six finals appearances and six medal wins (five of them gold), Phelps certainly had an excuse to be tired at what he insists was his final Olympic competition. However he characterized his time in Rio as “relaxing.”
“I think this is the most relaxed I’ve been for an Olympics which is awesome,” the new dad said. “It was very laid back and I wasn’t really nervous for any of the races.”
•With reporting by STEVE HELLING