Michael Phelps has added to his already staggering collection of Olympic medals, winning three additional golds at the Rio games, taking his total to 21. So what does the accomplished Olympian listen to to achieve such legendary success? What's pumping through those headphones to inspire such a nasty game face?

A recently published profile of the swimmer in The New York Times reveals that his pre-swim playlists include songs from Eminem, Jeezy and more. In previous years, Phelps has listed Lil Wayne's "I'm Me" as a go-to song to hype himself up, saying at the time, "Just the name of the song made sense to me, given where I'm at right now, and how I felt at these Games." He as well has included Jeezy's "Go Getta" on past playlists, so perhaps Phelps stays true to his past musical ways.

As for the Em track, "Lose Yourself" seems a likely candidate though "Til I Collapse" has some adrenaline effects as well. Two summers ago, Em was named the best artist to work out to, and this past October a separate study found that listening to the rapper will boost work out performance. President Barack Obama himself was seen bobbing along to Eminem's 8 Mile Oscar-winner at this year's Democratic National Convention, proving its everlasting impact.

There is still more swimming to be done at the 2016 Rio Olympics which means for Phelps, some more time with the headphones over-ear.

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