At the 2000 Sydney Games, Olympians raced through the 70,000 free condoms provided to them, prompting a second emergency shipment. Ahead of the 2012 London Games, 150,000 prophylactics were ordered for Olympians’ bedroom gymnastics.

All of that seems surprising given the widely held belief that sex is bad for sports. The coach of the Bosnia-Herzegovina national soccer team, for example, said in April:

There will be no sex in Brazil. … I am not interested what the other coaches do, this is not a holiday trip, we are there to play football at the World Cup.

Mexico’s players were also given a no-sex directive. Brazil’s manager takes a more nuanced approach, telling reporters, “The players can have normal sex during the World Cup.” To clarify, he added:

Usually normal sex is done in balanced way, but there are certain forms, certain ways and others who do acrobatics. We will put limits and survey the players.

Sports scientists haven’t dedicated a ton of time to exploring how sex affects athletic performance, so we don’t have a definitive data set on the issue. But I found several studies (suggest any others in the comments below).

In 2000, the Clinical Journal of Sport Medicine published “Does Sex the Night Before Competition Decrease Performance?” by Ian Shrier and Samantha McGlone, who had looked at 31 studies on sex and sports. They found that only three of those studies were scientific, and that none demonstrated any significant adverse effects from lovemaking (they ruled out the possibility of exhaustion, noting “normal sexual intercourse between married partners expends only 25-50 calories”). But those three studies were physiological; they didn’t investigate the psychological impact of sex. Given that sports psychology emphasizes the importance of anxiety, aggression and attitude toward competition, any evidence that sex could affect those things could lead to a different set of guidance for coaches.

McGlone and Shrier also emphasize (as these other studies do) that a lot depends on the individual: “Some people will improve with sex the night before competition (i.e., responders) and the performance of others will be hindered (i.e., nonresponders).”

So, the only definitive thing we can say here is that definitive bans by coaches amount to hedging their bets. Let’s hope for the sake of Bosnia-Herzegovina’s team (and their partners) that those coaches have made the right cost-benefit calculations.

I also found a few other related studies:

Recovery time

Findings: In this study, sexual activity had no impact on the maximum amount of workload that professional male athletes could achieve (as measured by heart rate) or on their mental concentration. However, the researchers did find that when they asked the participants to have “sexual relations” at 6 a.m., their recovery capacity was affected — which led them to conclude that “an athlete could be affected if he had sexual intercourse approximately two hours before a competition event.”

Participants in the study: Fifteen male athletes who train for about three hours per day, five days a week, and are participating in national and international competitions (one soccer player, seven hockey players, three cyclists, two long-distance runners and two weightlifters).

Year of publication: 2000

Source: Sztajzel, Périat, Marti, Krall and Rutishauser

Sleeping with someone means sleeping less

Maybe though, the emphasis on exertion is missing the point. Casey Stengel, former manager of baseball’s New York Yankees, may have understood the real risk to athletic performance when he said, “it’s not the sex that wrecks these guys; it’s staying up all night looking for it.” Compared to sex, the effect of sleep on athletic performance is rich with research, most of which is in consensus with the conclusions reached in the following study.

Findings: More sleep meant sprinting faster, reacting quicker and more accurate shooting, as well as “improved overall ratings of physical and mental well-being.”

Participants in the study: Eleven students on the Stanford University men’s varsity basketball team.

Year of publication: 2011

Source: Mah, Mah, Kezirian and Dement

Endurance

In the 1994 edition of Runner’s World, Marty Liquori, a U.S. Olympic runner, was quoted as saying, “Sex makes you happy, and happy people don’t run a 3:47 mile.” Does sex affect endurance?

Findings: The scientists found that immediately after sexual intercourse, 40 percent of long-distance runners felt weaker while they were at the anaerobic threshold (that basically means while they were exerting themselves a lot). Despite that, they couldn’t offer a definitive answer because their research showed that athletes “do not respond equally after being exposed to sexual intercourse in terms of their performance.”

Participants in the study: Sixty-two race-walkers and long-distance runners from six European countries.

Year of publication: 2010

Source: Pupiš, Raković, Stanković, Kocić and Savanović

What about female athletes? All these studies only considered the consequences for sportsmen. I couldn’t find a single study that examined the effects of sex on athletic performance for women (let me know if you find one).

But according to Barry Komisaruk, a psychology professor at Rutgers University, his research on orgasms could have implications for female athletes. In his book “The Science of Orgasm,” Komisaruk recounts studies that show the link between female orgasms and analgesia (the inability to feel pain). In one study, womens’ pain threshold was tested by gradually increasing the compression on their fingers — participants that had orgasms also had a higher pain threshold. Other studies referenced in the book found that orgasms could reduce the pain of migraines and menstrual cramps.