Incorrect PIN http://yuvututube.fun/ yuvutu In the early Fifties, Alfred Kinsey had investigated the bedroom habits of Americans with polite questionnaires; Masters and Johnson took a more direct approach. They recruited hundreds of admirably dedicated volunteers to shed their inhibitions, and their underwear, and have sex in laboratory conditions. They observed and analysed an estimated 10,000 orgasms for their 1966 book Human Sexual Response. It would alter our perception of men and women forever, revealing that women are the sexual athletes of the species, able to go on almost indefinitely after orgasm, while men need a rest.