Newbie question here.  Are these types of pants supposed top be essentially skin tight or form fitting....hence the name "compression?"   If they bag a little at the knees, drop to next smaller size?  I was trying some Reebock pants on at a sporting goods store and was just wondering.....thanks!

With all of your answers ( funny and sarcastic answers enouraged too!)  I will soon be an amazing fashion plate....albeit a slow one.