Michelle Jenneke: http://en.wikipedia.org/wiki/Michelle_Jenneke

Michelle "Shelly" Jenneke (/məˈʃɛl ˈdʒɛnəkə/; born 23 June 1993) is an Australian hurdler and model, who won a silver medal for the 100 m hurdles at the 2010 Summer Youth Olympics. She received worldwide media attention in 2012 for her pre-race warm-up, which involved dancing.

The warm-up in question: 

Michelle Jenneke World Star Hip Hop gifs: http://imgur.com/a/zI1Bf

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