Given the fact that there are approximately 100 million acts of sexual intercourse taking place each day, it’s estimated that one hour of sex can burn about 70-120 calories for a 60 kilogram (9st 5lbs) woman and 77-155 calories for an 80 kilogram (12st 6lbs) man.
Obviously the amount of calories burnt is reflected in how vigorous the love making is and the actual body weight of those involved!
It is worth keeping in mind that kissing for 1 whole minute will burn up 26 calories.