Given the prevalence of sexual relations — it may be the physical activity least likely to be skipped — the answers matter, and a bevy of recent studies offer preliminary answers, including some surprising new statistics about the typical age of someone who experiences a “sudden cardiovascular arrest” during sexual relations and the extent to which exercise improves sexual function and satisfaction.
But probably the most pressing question about sex and exercise is, “Is sex exercise?”
The answer, in various ways, appears to be yes. In a review article published in the Archives of Sexual Behavior, researchers at the University of Almería and the University of Murcia in Spain gathered every past study they could find that examined the physical exertions involved in coitus.
There weren’t many. As an activity, intercourse is difficult to study, for reasons ranging from politeness to politics. The studies the researchers found involved mainly committed, heterosexual couples, usually married, who often visited a lab for scientific observation of their exertions. On occasion, the coitus took place at the volunteers’ homes. Some of the couples wore heart rate monitors or other trackers. Others were filmed and their movement patterns analyzed. No one was blinded as to whether sex was taking place.
But even with these limitations, patterns emerged, the Spanish researchers found.
Sex counts as moderate exercise
Most obviously, sexual relations sped up the heart and burned through energy. In the studies in which people wore trackers, heart rates averaged between 90 and 130 beats per minute and peaked at anywhere from 145 to 170 bpm. Women’s heart rates tended to be lower than men’s.
The average caloric burn during intercourse also ranged widely, depending on people’s positioning, gender and more ineffable factors, such as whether they were at home or under observation at the lab. In one study, total energy expenditure during a single session of sexual activity reached 130 calories, while in another experiment, it topped out at about 101 calories for men and 69 calories for women.
These measurements indicate that “sexual activity can cause physical demands of moderate or even vigorous intensity,” said José M. Muyor, a professor at the Health Research Centre at the University of Almería, who led the review study.
The numbers are similar to those for a gentle run, except for the heart rate peaks, which rose higher than typical while jogging, and usually during orgasm, which is uncommon then.
As for the length of the sexual episodes, they likewise varied. In young, healthy couples in one study, sex lasted for an average of 32.38 minutes, while it continued for only about 19 minutes in another study among couples with health conditions, such as heart disease.
In all of the studies, duration was considered to start with foreplay and end with the male orgasm. Whether those parameters adequately capture the experience of both partners is disputable, but “we are limited to describing the methods and protocols that each study conducted,” Muyor said.
Other researchers recently have been probing whether sex, while briefly invigorating hearts, might also, under certain circumstances, stop them — and not metaphorically.
A noteworthy 2022 study in JAMA Cardiology, for instance, of casualties in London due to sudden cardiac arrest within an hour of sexual relations found that such deaths were reassuringly uncommon.
Of 6,847 fatal sudden cardiac arrests referred to one pathology center in London between 1994 and 2020, only 17 occurred during or almost immediately after intercourse.
But of those 17, six were women, which was unexpected, and most were relatively young. The mean age was 38.
Similarly, a 2018 study in Paris of people who survived sudden cardiac arrests between 2011 and 2016 found that about 0.6 percent, or 17 in total, all of them men and most in their 50s, went into cardiac arrest during or soon after sex. By comparison, 229 of the other cases occurred during sports or other exercise, and 2,782 in other situations.
Interestingly, resuscitation attempts on the men who became afflicted during or soon after sex tended to begin later than in the other situations, perhaps because of partners’ disbelief or “some degree of embarrassment,” said Eloi Marijon, a professor of cardiology at Paris University and co-author of the study.
“We do not have the marital status of the partners,” he added.
But the primary finding of his and other research in this area is that cardiac arrests during or due to sex remain vanishingly rare, he said. And the more someone engages in intercourse, the more the risks drop.
“During any physical activity,” he said, including sex, “the risk of cardiac arrest is higher than at rest.” But hearts, like other muscles, strengthen and grow more resistant to arrest the more people exert themselves, including with sex. “Sexual activity,” he said, “should not be seen as a riskful situation.”
It also is unlikely to compromise tomorrow’s competition or workout, despite widespread myths to the contrary. (“Women weaken legs,” Rocky’s trainer warned him in the 1976 film.)
A 2022 review published in Scientific Reports concluded that “sexual activity within 30 [minutes] to 24 [hours] before exercise does not appear to affect aerobic fitness, musculoskeletal endurance or strength/power.”
The review, which pooled data from nine studies, involving 133 people, almost all male, who had sex in the hours before some type of physical test, also found that coitus did not improve physical performance.
Sex, in other words, was a wash, which is perhaps comforting both for people who are and those who are not sexually active.
“I would say there is no reason to avoid or promote sex before a race or sexual competition,” said Gerald Zavorsky, an incoming professor of physiology and membrane biology at the University of California at Davis, who led the review.
Of course, thinking about sex solely as a competitive tool or even just as another form of moderate exercise is to risk diminishing some of its poetic mystery and intimacy.
On the other hand, if you should choose at any time to think about exercise as a way to improve sex, that would seem to be fine. In a 2019 study of more than 6,000 men and women, the more people exercised, the less likely they were to report erectile dysfunction, among the men, and sexual dysfunction, among the women.
Do you have a fitness question? Email [email protected] and we may answer your question in a future column.
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