When obliviously lip synching along to an mp3 player mid treadmill session progresses to belting out a line or a whole tune in a busy gym environment.

The Treadmill Karaoke-er may be oblivious to their faux pas, and may result in declarations of love, hate or violence to other gym users depending on musical preference.
Dude 1: Did that girl on the treadmill just ask me to put my hands up if I'm in love?

Dude 2: Hmmm, I think she's just doing some treadmill karaoke to JLS
by swallmeister December 30, 2011
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