Stretching: I've been doing it wrong for years.
 

I just got home from the gym and met the most incredible personal trainer (she was hot as fuck, too!). She saw me stretching before my workout, and stopped me. She said to NEVER stretch before lifting weights. The reason is because it causes your central nervous system to pause, which negatively affects your gains. She said to stretch after a workout to help recovery.

Learn something new every fucking day! Boom! :thumbsup