Over at DrivelineMechanics.com, Kyle Boddy has just published an article on overtraining - Training: Overtraining, or "What I See in High Schools Every Day".
He mainly refers to high school athletes, but I can personally attest to this being a problem at higher levels including college and the professional ranks.
When I played in college, our first pitching coach was only 2-3 years removed from his days as a Minor League Baseball player. The head coach had him develop the off-season strength program for our pitchers (myself included). He went with what he knew and gave us what he had been given as a professional athlete.
What we wound up with was a 2-day cycle, repeated 3 times weekly. Monday through Saturday, we lifted heavy, and we lifted a ton. We were graciously given Sunday as our day to recover.
This is a perfect example of both overtraining and not respecting recovery. For more, read Boddy's article.