Most men have erections every hour to hour and a half during sleep. The combination of blood circulation and testosterone production can cause erections during sleep and they're often a normal and necessary part of REM sleep.
 | How To Stretch Your Carbohydrate Intake |
 | How Successful People Think (Hint: It's Not All About Being Positive) |
 | 30 Reasons To Be A Fitness Freak |
 | 12 Unique Races To Run In Your Lifetime |
