Why Men Fall Asleep After Sex, and Other Answers

Aug. 4, 2006 — -- Co-authors Mark Leyner and Dr. Billy Goldberg give answers to questions ranging from the bizarre to the slightly embarrassing in "Why Do Men Fall Asleep After Sex," their follow-up book to their No. 1 New York Times bestseller, "Why Do Men Have Nipples?"

From questions about dogs' belly buttons to knocking down old wives' tales -- no question is too weird for this duo.

The authors answer a few of those important medical questions below.

"Why Do Man Fall Asleep After Sex" is available in bookstores now.

Question: So you put it out there -- and we've got to ask: Why do men fall asleep after sex?

Leyner: People have no idea how much work it is for a man to produce an ejaculation. You have this seminal vesicle churning out this fluid, the prostate gland producing an alkaline solution. It's like having five iron chefs in your crotch working to cook up this stuff.

Goldberg: There are hormones that are secreted at orgasm -- proloactin, oxytocin --that facilitate sleep. But you have to accept as gospel that men orgasm more than women. If that's true, then you have your answer as to why men fall asleep after sex. ...And it seems like women don't. If women orgasm as much as men, we might all be asleep all the time.

Question: Who snores more -- men or women -- and why?

Leyner: Men snore more and a lot of it is anatomic. Men's airways aren't as wide as women's and when men gain weight they gain it around their neck which constricts the airways. Women, on the other hand, gain weight in their hips.

Question: Who listens more -- and why?

Leyner: There are some physiological reasons behind the cultural stereotype.

Goldberg: It's not that we listen less -- it's that we listen differently. A couple of studies used MRIs to look at men versus women, and what happens inside their brains while they're listening. Men use one side of their brain whereas women use both sides. And when men hear women's voices they hear those voices in different areas of the brain than women -- they hear women's voices in the same area of the brain they use to process complex musical sounds -- so you can extrapolate the women's voices are more complex. ...And more difficult for us to listen to.