I know some of my buddies do this after a hard workout, and mabey some of you do so you do not get as sore the next day (or think it will help). Here is a study done to show the effects of taking such drugs after working out.

http://ajpendo.physiology.org/cgi/co...t/00352.2001v1

"These results suggest that over-the-counter doses of both ibuprofen and acetaminophen suppress the protein synthesis response in skeletal muscle following eccentric resistance exercise. Thus, these two analgesics may work through a common mechanism to influence protein metabolism in skeletal muscle."