The line comes from Lose Yourself, Eminem's 2002 song written for the film 8 Mile, where it opens the first verse as his character prepares to rap in front of a hostile crowd. The full opening, about sweaty palms, weak knees and heavy arms, became one of the most quoted passages in hip-hop. As short clips spread on TikTok, YouTube and soundboards, the first phrase was lifted on its own as shorthand for stage fright and performance anxiety. It remains popular because the image is simple, physical and instantly understood, even by listeners who do not know the whole song.