A grade school memory of mine is from the required track & field day.
I decided to run in one of the shorter sprinting races, probably the 100m, of which I have no actual recollection of.
However I do recall deciding to not warm up for the event..at all. Why would I want to run and waste energy, before having to race?
I came in last.
Click here to read more about warming up, including how I recommend it be done, why you should not be afraid of a hard warm up, and its affect on delayed onset muscle soreness!