Sex is good for you in lots of ways. It helps lower your blood pressure and reduces stress, and some experts also believe it boosts your immune system. And of course, it's good exercise too.
But if you're not used to exercise and you suddenly launch into a steamy sex session - if you're not having sex regularly and you have a one-night stand, for instance - it could be bad for your heart. And according to Boston researchers, it could even kill you.
Writing in the Journal of the American Medical Association, the experts investigated the effect sudden spikes in activity can have on people who don't get regular exercise. And having analysed information from 14 different medical studies that examined the link between exercise, sex and heart attacks, they came up with some startling statistics.
If you don't normally do much exercise you're 2.7 times more likely to suffer a heart attack while having sex or immediately afterwards, compared to when you're not doing any physical activity. And if you suddenly start exercising - while jogging, for instance - you're 3.5 times more likely to have a heart attack compared to when you're sitting around doing nothing.
The more active you are on a regular basis, however, the less likely you are to suffer any heart problems while having sex or exercising, say the researchers.
But if you're not in a relationship or having sex on a regular basis, don't get too freaked out. The number of heart attacks that are actually triggered by sexual activity is still quite small, admit the researchers.