Why do guys get sleepy after sex?
-- asks J. from Brooklyn, NY.
Melinda Wenner • September 25, 2006
![The sated Satyr. [<em>Sleeping Satyr</em>, marble copy of bronze original, unknown sculptor c. 200 B.C.]](https://scienceline.org/wp-content/uploads/2006/09/370px-sleeping_satyr.jpg)
The sated Satyr. [Sleeping Satyr, marble copy of bronze original, unknown sculptor c. 200 B.C.]
For many women, the correlation between sex and snoring is one of those annoying facts of life: no matter when passionate encounters occur, men always seem to fall asleep immediately afterwards. Dave Zinczenko, the author of Men, Love and Sex: The Complete User Guide For Women, explained the phenomenon to Huffington Post writer Arianna Huffington this way: “Men go to sleep because women don’t turn into a pizza.”
I doubt I am ever going to become a pizza, and I’ll never have the foresight to order one beforehand. So in lieu of a cure, a better explanation will have to do. Although women sometimes feel sleepy after sex, the phenomenon does seem more pronounced in men. What is it, then, that spirals them into the land of nod?
First, the obvious reasons for sex’s somnolent sway: the act frequently takes place at night, in a bed, and is, after all, physically exhausting (often more so for the man than the woman, although this certainly varies). So when sex is over, it’s natural for a guy to feel sleepy.
Secondly, research using positron emission tomography (PET) scans has shown that in order for a person to reach orgasm, a primary requirement is to let go of “all fear and anxiety.” Doing so also tends to be relaxing and might explain the tendency to snooze.
Then there is the biochemistry of the orgasm itself. Research shows that during ejaculation, men release a cocktail of brain chemicals, including norepinephrine, serotonin, oxytocin, vasopressin, nitric oxide (NO), and the hormone prolactin. The release of prolactin is linked to the feeling of sexual satisfaction, and it also mediates the “recovery time” that men are well aware of—the time a guy must wait before “giving it another go.” Studies have also shown that men deficient in prolactin have faster recovery times.
Prolactin levels are naturally higher during sleep, and animals injected with the chemical become tired immediately. This suggests a strong link between prolactin and sleep, so it’s likely that the hormone’s release during orgasm causes men to feel sleepy.
(Side note: prolactin also explains why men are sleepier after intercourse than after masturbation. For unknown reasons, intercourse orgasms release four times more prolactin than masturbatory orgasms, according to a recent study.)
Oxytocin and vasopressin, two other chemicals released during orgasm, are also associated with sleep. Their release frequently accompanies that of melatonin, the primary hormone that regulates our body clocks. Oxytocin is also thought to reduce stress levels, which again could lead to relaxation and sleepiness.
What about the evolutionary reasons for post-sex sleepiness? This is trickier to explain. Evolutionarily speaking, a man’s primary goal is to produce as many offspring as possible, and sleeping doesn’t exactly help in his quest. But perhaps since he cannot immediately run off with another woman anyway—damn that recovery time!—re-energizing himself via sleep may be the best use of his time.
And although there is conflicting information as to whether women feel sleepy after sex, a woman often falls asleep with the man anyway (or uses it for some key cuddling time), which is good news for him: it means she is not off finding another mate. When the man wakes up and she’s still there, he just might be ready to go again.
It’s also possible that sleepiness is just a “side effect” associated with a more evolutionarily important reason for the release of oxytocin and vasopressin. In addition to being associated with sleep, both chemicals are also intimately involved in what is called “pair bonding,” the social attachment human mates commonly share. The release of these brain chemicals during orgasm heightens feelings of bonding and trust between sexual partners, which may partially explain the link between sex and emotional attachment. This bond is favorable should the couple have a baby, as cooperative child rearing maximizes the young one’s chances for survival.
The bottom line is this: there are many potential biochemical and evolutionary reasons for post-sex sleepiness, some direct and some indirect—but no one has yet pinpointed the exact causes. One thing, however, is certain: we females better get used to it, because it doesn’t look likely to change anytime soon.
I will leave frustrated American women with one final thought: if you are upset at the ubiquity of the post-sex snoring phenomenon, remember that things could be a lot worse. A recent survey of 10,000 English men revealed that 48 percent actually fall asleep during sex.
Talk about coitus interruptus!
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About the Author
Melinda Wenner
Melinda Wenner gave up a much higher salary, a BMW and a comfortable life in the British suburbs in order to write for Scienceline. She is willing to trade her knowledge of molecular biology (and perhaps her list of sources) for a well-poured pint of Carling. Contact her at whathaveidone@hotmail.com.
313 Comments
ok people unlike most guys i usually last about 6-8 hours so me and my girlfriend are both out cold
I found it irritating at first, whenever my hubby fell asleep right after sex. coz i come up with all kinds of questions after sex. but now i don’t mind it anymore and i try to go to sleep too. its real hard for me to shut up but i’m trying.
I only fall asleep if I ejaculate, no matter if during intercourse or masturbation. If I stop just short of ejaculation, there is no falling asleep, even if I did lots of push ups, breathe the same un-oxygenated air, move her from the floor to a sofa and then to the bed again (of course, I get tired doing this, but don’t fall asleep).
In my case, things get a little aggravated by the fact that I suffer from sleep aphnea and when I fall asleep, I fALL ASLEEP and SNORE.
Thank you Melinda. It has done a lot of good that I found this forum because now wife understands that is not me being careless about our relation, it’s just nature.
SEX IS A SAFE SLEEPING PILL….PERIOD!!!! ONE THAT YOU CAN NEVER OVER DOSE ON SO SLEEP AWAY
i agree with whoever said, “if he does the job right, then she’d be asleep soon after” (her third orgasm…) and anyway, after he’s “performed” for an hour or longer, he deserves a good nap! nothing wrong with that as long as you sleep cuddling ‘braid’ style, as i call it. good sex with a partner you love and respect is the best gift the universe can give two people!
may you be as fortunate as to find someone you connect with so well!
it was fun reading the article AND people’s feedback!
in good health, Peace to All ~happy~
any way the ‘name’ on #55 be changed to happy? not fair!
i have a boyfriend named sebastian
Some interesting stuff here, some quite thought provoking, but with regard to the UK survey of 10,000 men you should either name the survey/source or retract this insulting unsuported comment that denigrates your article.
Heya guys and girls, I totally agree with all the chemical reactions happening to make a guy all sleepy, I also agree with the “work” that’s put in from a guy (or at least me) – Aussie girls a blabber mouths so we guys here like to keep it up and keep it going and learn heaps about pleasing girls so we don’t get a bad name. So if that means 3 half hour sessions with plenty of foreplay and no naps in between, then all up both parties need some rest hey? After my trips to the UK and America, I can safely say as a 23 year old fit Aussie guy that girls aren’t hard to please the world over if you do some research and practice, practice and practice = )
brendan.hinds@gmail.com – http://www.myspace.com/longevity99
For those who want to know the source of the statistic about English men falling asleep during sex:
http://www.dailymail.co.uk/pages/live/articles/health/menshealth.html?in_article_id=338126&in_page_id=1800&in_a_source=
For those who have an abnormal fatigue during 2 to 3 days after sex (and different symptoms, pale face, sweats, lack of concentration…), you can join this thread :
http://www.thenakedscientists.com/forum/index.php?topic=6576.0
miryam love sex very much from lebanon
miryam from lebanon love sex veryyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy much
THERE IS GOOD NEWS FOR US MEN, I JUST GOT DONE (DOING IT ) AND IM A VICTIM OF THE SLEEPINESS THING TOO BUT IF YOU JUST GET UP RIGHT AWAY AND START DOING SOMETHING IT WILL GO AWAY!! FOR EXAMPLE I DECIDED TO GET UP AND ASK THE QUESTION (WHY DO MEN FALL ASLEEP AFTER SEX) AND 15 MINUTES LATER IM WIDE AWAKE TYPING THIS!! DAMN I SHOULD GO WAKE MY WIFE UP !!LOL
“somnolent sway” and “coitus interruptus” in one article. stunning
^
i agree. amazing.
you know… if you do it right, the girl falls asleep right after too ;)
Well… this article truly shows how hard it is to please women these days, so why bother?
After you spend time, money, and energy getting them into bed… they bitch about you falling asleep afterwards. I thought it was just me…!
You’d think they would be used to it by now, and it’s perfectly normal ~ which is exactly what this article says.
From now on, I’m going to make it a policy to do even less… after orgasm, I think I’ll whisper in her ear, “Gotta go, babe… Pizza Palace said my order would be ready by now… see ya later!”
Men… We’ve got the balls…they don’t. If they don’t like us falling asleep after sex, just get up and leave. You have to go pee, don’t you? Flush your plumbing, leave, and go someplace else. Make any excuse to go. Leave them all by themselves, and after a while, they may appreciate it when we occasionally fall asleep in bed with them.
we men don’t have to fall asleep after and alot of times don’t ! but when i’m comfortable and feeling her in my arms, there is nothing better !!! that’s where i want to be and nodding off there is perfect!!!
Good topic
my husband has this problem, whenever i complain of not being satisfied he coild always say i am tired and get asleep while we have sex. Sex issues are important as a couple to be discussed.
Why does it really matter that a guy falls asleep afterwards? You have to be quite petty/insecure to get worked up about such a trivial matter, in my opinion.
Great article, enjoyed reading it, and the comments. =D
Stupid article. Even cursory research on this subject will show that the reason men become sleepy after ejaculation is a sudden loss of blood pressure.
Everything mentioned in this article does not account for the sheer rapidness of the sleepiness. Loss of blood pressure does.
When a man is having (good) sex, his heart beats over 100 times a second. Once he ejaculates, his brain says, “holy crap, I can’t keep this heart rate up for long, I’ll have a heart attack!” So the heart suddenly slows down. This quickly and greatly reduces the blood pressure and the brain reacts by putting the body in sleep mode.
It’s not rocket science.
In response to Dave’s comment: it is not possible for a human heart to beat 100 times per second. A hummingbird’s heart only beats 20 to 50 times a second, so I will assume that’s a typo and you meant to say 100 times per *minute*.
100 heartbeats per minute is normal heartrate for both male and female adults. In fact, I just took my blood pressure now, sitting in front of the computer, and it’s at a hundred. As for acceleration during sex, the heart doesn’t usually reach past 130 beats per minute during orgasm … that for both men *and* women. You can get your heartrate that high just by running on a treadmill. That alone is not condusive to falling asleep … people don’t typically drop off to sleep at the gym.
Melinda’s article explores not why sex makes people tired (that much is obvious as you stated) but specifically why men seem to fall asleep *more quickly* than women susually do. I found her article to be interesting and informative, and respect that she cited several possible suggestions and sources while committing personally to none.
Dave’s right. It’s the rapid loss of blood pressure. Google it.
well its out of the topic but im just wondering if “Is a woman still virgin after having masturbation like rubbing pillows to trigger sensation enable her to feel wet”
You’re ignorant.
Well, needless to say this is a rather interesting article; however, you forgot to mention one thing. The reason most women cannot fall asleep quickly – weather after sex or not- is that they have a difficult time turning off the flow of new thoughts. Men are not so. I can personally fall asleep anytime, anywhere. Now, after sex, that’s a different story. I prefer to remain awake after sex. There is the occasional time where I will get sleepy, but generally it’s after a long and tiresome day. Also, I’ve decided that I have a Prolactin deficiency, because my recovery time is generally 10 – 15 minutes maximum. But, all in all, it was a very informative article and rather well written I must add.
Blood pressure is a very plausible explanation for the phenomenon of post-sex drowsiness; however, I don’t think the “evolutionary” process of man had anything to do with it. I don’t know… Maybe it’s just me, but I don’t see the Neanderthal men and women just haphazardly fornicating and then men dropping like flies and the next wave of men steps up to the challenge. If this were true then there would be some remnant of it both in our culture and in our subconscious.
To be perfectly honest, what does it matter. I hope women don’t take a man falling asleep as an insult. It is the exact opposite, in fact. A man falls asleep because it is the only thing he can do after the pure euphoria of an intercourse orgasm. He is satiated on many levels, not just physically. A partnered orgasm leaves you satisfied emotionally, mentally, spiritually, and physically. When all four facets of human nature are satisfied, the only logical response is – Sigh – a good night’s sleep.
I’ll be through, for now; however, before I leave I would like to propose another question. Why do I feel the urge to burst into laughter after an exceptionally satisfying “romp in the sack”?
Thanks for all your hard work.
PS… Mirmo is ignorant!!
~Michael
it says in the article that men seem sleepier after masturbation rather than intercourse with a partner. but i find that its the opposite for myself. is there any reason for this?
whats it means a man get sick after sex? I get rlly sick right after I cum, I throw up etc. Does any one know what that mean??
I get sick after having sex, I actly throw up. does anyone know what it means?
Uh, steve… It means your gay!!
Steve, i think it means your BMI is very very high :p
Has anyone tried working out after orgasm? Gets the heart pumping, and increases energy levels, combine this with a protein bar, ready for more? I have done this, you get tired but it’s similar to food coma, you can fight it.
As for women not being tired, maybe cause they just lay there? Men die earlier cause they do everything, all the work is on the men. If you want your man to find the good spots then YOU need to know where they are.
LOL…sheesh awesome article!!! SEX is like Maccas- MMMM I’m Lovin’ It!
As long as a woman is educated that this has nothing to do with how you feel about them, then there should be no problem here.
Woman are always going to be upset about something, I have taken this to be way of the world.
As long as you handle them appropriately in an manor that shows that you care there you will be fine.
If they still cant deal with this then too bad for them maybe men should start complaining because women menstruate?
Love how all the Englishmen jump in calling it all lies and rubbish! How would you know? Do you discuss your sex life with every other Englishman you see on the street? I’m pretty sure someone who took the time to research all that, enough that even you took a gander, has her facts straight. She wasn’t saying Americans are better at sex she was just citing a research study. It’s funny how you resort to calling Americans fat and “ponces” (an insult most Americans don’t get/couldn’t care less about) to defend yourselves. Makes you sound all the more like the picture perfect top hat toting sexually incompetent Englishman dweeb.
a great article
i actually find it really comforting when my boyfriend falls asleep with me afterwards (:
yup i just had sex and i felt sleepy and i woundered why i always do. this artical answerd my question!
Another good reason for sex in the morning *after* a good night’s sleep.
After the first time I have sex I can’t get hard, atleast not for 40 or so minutes, a few months ago i had no problem getting hard in 15 mins. Is there a diet issue or something?
I think the last throw away comment about English men is misleading. First, the author seems to be quoting a Daily Mail article that quotes the results of a questionnaire handed out at a trade show: hardly published article in a respected peer reviewed journal. Second, the author seems to have deliberately mislead the audience by implicating that 48 percent of men fall asleep during sex on a regualar basis where as in the Daily Mail article: “The survey found 48 per cent of men had actually fallen asleep during the act itself”. Obviously, the meaning is very different.
It is a real shame that the comment was made at the end of this article as it puts into question the validity of the whole article. If the level of journalism, not to mention science writing, is below that of the Daily Mail then the author should really consider improving her skills before considering a career in science and/or journalism.
My boyfriend occasionally falls asleep during initiation, mostly because he refuses to go to bed until he is knackered, but if we have sex in the morning, he lies with me for 5 minutes telling me how much he loves me etc, then gets straight up to sort himself out. Whereas I’m knackered and stay in bed for another half hour to an hour.
I wonder why this is…
Well said Billy .
Good example of why you shouldn’t believing everything you read – especially considering the lack of editorial censorship on the net .. not to mention the high volume of armchair experts out there..
Good grief, 93 answers and not a single urologist? See Simmons and Jones, “Male Genital Morphology and Function: An Evolutionary Perspective,” J. Urology, 177, 1625-1631 (2007). “… males with favorable genital traits have higher paternal success.” Besides maximizing volume of ejaculate reaching the os, the male’s other main goal is to fight off sperm from competing males. The “massive piston” of primates, combined with a long time to ejaculation, serves to pump out the sperm of the preceding partners, while greater length deposits the sperm closer to the os for greater efficiency (tradeoff: a too-long penis is hard to keep rigid, and also more vulnerable to accidents like stepping on it). Drowsiness afterwards (i) plugs the vagina to prevent sperm loss (species needing a quick getaway deposit instead a very gelatinous ejaculate serving the same purpose), (ii) prevents the female standing and losing sperm, and (iii) holds off the competition (the “leaves” in the “eats, roots, shoots, and leaves” strategy is suboptimal).
After sex I tend to want to leave. I’m pretty sure it’s referred as “hit it and quit it”
You state, “Research shows that during ejaculation, men release a cocktail of brain chemicals.” Which chemical(s) contribute to the lowering of blood pressure?
haha they said masterbation!!!! :o
you all are right me and my boyfriend did it but when we were finished he snored like a pig and i woke him up because i wanted more that shit felt good and it really was good he loved it to and i humped that bitch until he could not take nomore.when i was finished we both went to sleep
well… i actually got here because i was looking for an explanation why it’s my girl that’s so sleepy after. i tried to sleep with her but she just dozes off too long that my head and back starts to ache from staying too long in bed.
**Points to 91.**
“The survey found 48 per cent of men had actually fallen asleep during the act itself.”
note: HAD
I have a question. I am a male. During sex, and after sex I feel great (as we all should),but after a few hours afterwards I start to wheeze and have trouble breathing. It’s as if the orgasm has given me asthma. Has anyone ever had this problem of know soeone who has. What could cause this?