A good kip is another reason a man may feel even more amorous in the morning. But, sexual desire in women is not a simple story. The tests were given two weeks before they saw their partners, the day before, before sex, the day after sex and three days after the pair were separated. In one study of women athletes, their testosterone levels significantly increased after long runs. Studies have shown, that an after-work gym session can boost the libido of both genders. The hormone is needed to trigger muscle growth and sperm production. Men with more testosterone are also more likely to be found attractive by women, according to researchers at Wayne State University in Michigan, US. It all comes down to hormones. Why do men want sex in the morning while women get frisky at night? Downey says it takes more than hormones to get a woman in the mood, so men need to make an active effort. Men need only a normal amount of testosterone to feel like having sex. The tests were given two weeks before they saw their partners, the day before, before sex, the day after sex and three days after the pair were separated. Researchers believe the reason is that music may make women feel more relaxed, bonded and in turn more sexual, while in men it calms their aggression and in turn reduces their levels of testosterone. If a woman sees herself as unattractive, she is much less likely to want to have sex. And why, late at night, when a woman is in the mood for love, is her man just lying there, snoring? Could not subscribe, try again laterInvalid Email Why is it that a man feels at his sexiest when he wakes up in the morning but a woman wants to go back to sleep?