Not to have

Sex as a work out may seem like a good reason, but think about it... 200 calories? It's really not that much if you think about it. 200 calories is just a tenth of a 2000 calorie diet. It's even less for say, an athlete, who can easily have a diet of 3000+ calories.

Here's a reason not to have sex before marriage: STDs.

The clap. Herpes. HIV. Lice.

A study by the CDC reported that over 1 million NEW cases of chlamydia were reported in 2006.
At the beginning of 2003, the CDC estimated that 1.1 million people had HIV, and that a quarter of them didn't know it.

I don't know, Spence... I think I'm gonna spend 10 more minutes on the treadmill to burn those extra calories.