A person who runs super fast during a warm-up, but then sucks the whole rest of the practice (usually in cross-country or track).
Girl: Look at him! He's so fast!

Boy: No, he's just a warm-up warrior
by Rad_Darkthor August 28, 2012
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A warmup warrior is a person that sprints the warmups. This could be in any team sport from track to swimming. These people are usually slow in the main part of the practice and dislikes by others.
1: Dang, Karly is such a warm up warrior
2:Yeah, it’s super annoying, wait till the main set
by Popculture February 2, 2019
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