Researchers into human sexual behavior have to endure struggles for funding and snide jokes from the other nerdy scientists at academic conventions. But without our fearless human-sex researchers, we wouldn’t have Viagra and we’d never have known that when a woman orgasms, she releases an endorphin that kills pain, including any headache she may have said she had. Useful, no? Grab the FHM February issue for an uncensored tour of sex’s weirdest secrets... but to help whet your appetite for the new issue, here's a sneak peek at just one of the secrets we uncover... 

Fighting the urge won't do you any favours

Science has thankfully rid us of the myth that if you lose any of your precious semen to anything but a real woman, you will be draining yourself of life force. Victorians believed this so strongly that they invented the Penile Pricking Ring in the 1850s, which men slipped on before falling asleep, so that the metal spikes inside the ring would wake them if their naughty penises expanded to have a wet dream. 

Masturbation was seen as the ultimate waste of life force and was to be avoided at all costs. The irony, of course, is that it’s actually a pretty good idea to recycle your sperm every so often. Sperm that sit around in your pipes for more than a week start to become abnormal — some develop extra heads, shriveled heads, bent heads and some have no heads at all. If you’re not planning on fathering any children, making your little soldiers turn retarded might be the way to go.

But sex physiologist Roy Levin recommends that if you’re looking to build up a powerful fleet of healthy sperm to impregnate your woman of choice, give your boys five days to build up their ranks...