Given the money and fame at stake, is it any wonder pro and aspiring-pro athletes, such as the baseball players recently named in the George Mitchell report, use banned performance-enhancing drugs?

Baseball players and Olympic athletes are not the only ones popping and injecting: almost 6 out of every 100 high school students are using these substances.

But how do they work, and why are drug tests not always effective in trying to catch users?
Anabolic Steroids: What Are They?