Sex offers more exercise than walking although it does not burn as many calories as jogging, according to a study at Quebec University in Canada.
The study involved 21 couples between 18 to 35 who were required to wear an energy-sensor on their arms. The device, called SenseWear, measured how much energy they spent when exercising on a running machine for 30 minutes and when they had sex.
The sensor is capable of detecting heart acceleration, body temperature and changes in the amount of current passing through the skin. The more people sweat, the more current pass through the skin.
The study showed that people spent an average of 24.7 minutes having sex, and men burned off 101 kcal on average each time they did. That came down to 4.2 kcal every minute.
In comparison, exercising 30 minutes on a running machine burned off 276 kcal or 9.2 kcal a minute.
Women burned off less calories than men at 3.1 kcal a minute during sex and 7.1 kcal on the running machine, which averaged a total of 69 kcal having sex and 213 kcal running.
A researcher said sex does not burn off as many calories as jogging at 8 km/h but is better than walking 4.8 km/h, adding sex could be a "good substitute" for people who don't like to exercise, since most of the participants perhaps unsurprisingly said sex gives them more pleasure than the treadmill.
Until now, sex was thought to burn off between 100 to 300 kcal, but the Quebec University study is the first to use scientific tools to measure it.
The findings were published in the Oct. 24 edition of the scientific journal PLoS ONE.