What did Atilla the Hun, Nelson Rockefeller, and French President, Felix Faure all have in common? They all died while having sex.¹ There’s been much comedic snickering in the past about people who keel over while messing around, but now science tells us it’s no joke. A recent study out of Tufts University just published in the Journal of the American Medical Association found that the chances of having a heart attack increase 2.7 times during and right after sex.² The risk is greatest for normally sedentary people who engage in what the researchers euphemistically call “episodic sex,” meaning sex once in a blue moon.

The Tufts study was part of research into how moderate or intense physical activity affects sedentary people. But here’s the big surprise. While sex certainly seems to strain the old ticker in this population, sex isn’t the biggest risk factor — exercise is. The chance of having a heart attack leaps by 3.5 times during a workout compared to when at rest for those who don’t normally exercise. Even more dramatically, the risk of sudden cardiac death skyrockets by a factor of five.³

“Based on our review of 14 case-crossover studies of acute cardiac events,” the researchers write, “we found a significant association between episodic physical and sexual activity and acute myocardial infarctions and suggestive evidence of an association between episodic physical activity and sudden cardiac death. Most importantly, these associations appear to be strongly modified by habitual physical activity, with individuals with higher habitual activity levels experiencing much smaller increases in risk compared with individuals with low activity levels.”

But here’s the irony. While having sex once in a while sharply increases your risk of death by coronary, having lots of sex regularly decreases your risk. A study in 2010 published in the American Journal of Cardiology found that men who had sex twice a week had a 45 percent reduction in heart disease compared to men who had sex less than once a month.⁴  The same equation holds for exercise. In fact, the researchers found that for each exercise session you enjoy during the week, you lower your heart attack risk by 45 percent, so twice a week brings a 90 percent reduction. While you’re more likely to have a coronary during a roll in the hay or a spin on the cycle if you’re a candidate, you’re a whole lot less likely to be in that category if you’ve been going to the gym or the mattresses (in the matrimonial sense) regularly.

If you think that you can just tone down your antics in bed to cut your risk, here’s something to chew on. The problem with sex is not just that the heart muscle gets taxed in all the excitement. “Emotional arousal [during sex] will also increase adrenaline and get heart rate going even in the absence of physical exertion,” says cardiologist Dr. Philip Ragno. So unless your partner looks like Medusa and turns you into stone, you’ll be taking your chances in bed if you haven’t been staying fit.

On the other hand, as with most studies, this one too needs to be taken with a grain of salt because the overall risk of dying or having a heart attack during a sexual encounter really isn’t great. According to a 2010 study published in the Lancet, only 2.2 percent of heart attacks happen during sex. The window of risk is small, lasting only two hours after sex. Eating a heavy meal puts you at greater risk, at 2.7 percent. And of course, eating a heavy meal will probably not put you in the mood for exercise, which would compound the risk if you exercised after eating, so you can see where that pattern is heading. Ah! But what about eating a heavy meal and then having sex? I’m sure Tom and Jenny Jones would have something to say on that score.

Translated, this means that getting in shape now is imperative if you don’t want to go the way of Atilla the Hun. If you’ve been a complete sloth for a while, you need to transition into activity slowly. You can’t go from no exercise to running marathons overnight without putting yourself at great risk. Best to start out with some simple exercise like walking for a short period every day, and then add on another 10 minutes every few days until you’re ready to move into more strenuous activity.

In case you’ve missed the point, the researchers don’t want the study to scare people into planting themselves on the couch to avoid strain. As cardiologist Dr. Chip Lavie of the Hohn Ochsner Heart and Vascular Institute says, “The main take-home [is that] regular exercise training, which we should be promoting anyway as a means to improve cardio respiratory fitness…will markedly reduce the risk associated with both acute exercise/exertion as well as sexual activity. The bottom line is that people should not fear sexual activity, but should fear sedentary lifestyle and physical inactivity.”

By the way, if after building up stamina through regular exercise, you still don’t have enough oomph to have sex more regularly, check out this blog on alternatives to Viagra that both increase sex drive and make you feel better overall.

¹7 Famous People That Died During Sex.” Comedy.com. March 22, 2011.
² Increased Cardiac Risk Linked to Occasional Exertion, Sex.” 22 March 2011. Psych Central. 24 March 2011. http://psychcentral.com/news/2011/03/22/increased-cardiac-risk-linked-to-occasional-exertion-sex/24548.html
³ Gardner, Amanda. “Study: Infrequent Sex Can Raise Risk of Heart Attack, Death.” 22 March 2011. Bloomsburg BusinessWeek. 24 March 2011. http://www.businessweek.com/lifestyle/content/healthday/651113.html?campaign_id=lifestyle_related
⁴ Heart Attack Risk: Does Having Sex Really Tax the Ol’ Ticker?” ABC News/Health. 23 March 2011. <http://abcnews.go.com/Health/MensHealth/heart-attack-risk-sex-tax-ol-ticker/story?id=13193752&page=2>