The myth of sex and athletes: is it good or bad before a competition?

You have probably wondered at some point whether Olympic athletes have a normal life. Do these people who perform amazing, seemingly superhuman feats behave just like any other young person in all situations?

And how does that relate to sex? Does the sexual activity have any effect on an athlete's performance? Do athletes have to be abstinent before a competition in order to perform well?

Most coaches recommend their athletes refrain from sexual relations before a competition, but is there any evidence for this recommendation?

Since ancient times, in Greece and Rome, it was thought that sexual abstinence was necessary since there had to be a "communion" between body and spirit. To ensure optimal performance, an athlete was supposed to rest before a competition and not engage in "distracting activities".

This recommendation has endured over the years and many coaches consider abstinence necessary because it is thought that sexual activity causes physical wear and tear and, in the case of men, ejaculation decreases testosterone, which causes a reduction in aggressiveness and muscle strength. Mohammad Ali used to say that he required six weeks of abstinence before a fight because to increase his aggression.

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Myth or reality?

As a doctor specialising in sports medicine, I worked for several years with a Mexican professional football team, and remember that the coaches recommended sexual abstinence to the players. Players were prevented from having visitors in their rooms before matches.

On the other hand, Dave Wottle, a middle-distance track athlete who won the gold medal in the 800 metres at the 1972 Munich Olympics, and Kerrin Lee-Gartner, an alpine skier who won a gold medal in the downhill event at the 1992 Albertville Winter Olympics, said that their victories were partly due to having sex before the races.

In more recent Olympic Games, such as London 2012, the International Olympic Committee distributed 150,000 condoms to athletes, which prompted a special report on CNN in which administrative officials, athletes and doctors gave their opinion on this event, stating that sex helps to relax, to be physically satisfied, as well as to get mental distraction from the competition.

They also mentioned that there is no scientific evidence on this and that caloric expenditure during sexual intercourse is minimal, so it seems that evidence has been based on anecdotal experiences. However, in medicine, anecdotal evidence is often not good - it's best to have proof so that the patient - or athlete - can receive the greatest benefit and that it will not have the opposite effect. It has to be objective, verifiable, reproducible and generalisable.

What does science say?

As sports doctors, when we talk about performance, we have different ways to monitor and measure it. You can measure strength, aerobic endurance, reaction time, memory, power, flexibility, testosterone levels, cholesterol and blood sugar, among other things.

Studies have therefore been conducted to measure some of these variables in relation to changes in sports performance after sexual intercourse.

These types of studies were initiated in 1968 by Johnson (Muscular performance following coitus∗. Journal of Sex Research) and in 1981 by Anshel (Effects of sexual activity on athletic performance. Physician Sports Med.), to try to demonstrate performance changes associated with sexual activity. But at that time, there was no basis for conducting rigorous clinical scientific studies. Consequently, the studies conducted are flawed in their design and are not generalisable. Systematic reviews and meta-analyses are conducted in order to find the best evidence by rigorously reviewing the publications on a topic.

There are currently two systematic reviews published in scientific journals on investigations into the effect of sexual activity on athletes’ performance. The first by Stefani et al. (Sexual Activity before Sports Competition: A Systematic Review. Frontiers in Physiology, 2016) conducted a search of publications related to performance and sexual activity.

The researchers found studies using questionnaires, blood measurements, strength and cardiovascular tests including both female and male athletes. Among the reported findings, there was insufficient evidence of negative effects on sports performance in relation to strength and endurance in individual and team sports after sexual activity. Neither was there any evidence of hormonal changes associated with sexual activity. However, the researchers point out that not enough sports have been studied and, more importantly, many studies lacked scientific rigour, had errors in study design and did not reflect real life.

In the second published review, Soori et al. (Sexual Activity before Competition and Athletic Performance: A Systematic Review. Annals of Applied Sport Science, 2017) report that there is no difference between the abstinence groups and those who engaged in sexual activity 10 hours before the competition, suggesting that it did not affect performance.

They even mentioned that sexual activity represented only an activity considered to be light to moderate in intensity and that it compares to climbing two floors of a building. Within the reviewed publications, one author mentioned that there is a negative effect when sex occurs two hours before a sports activity. But a single study cannot be generalised.

Both reviews stress the fact that individual factors and the habits of each athlete must be taken into account, and most importantly, many athletes want to feel free to make their own decisions in this regard.

Since there is insufficient evidence on whether sexual activity has any negative effects on sports performance before a competition and some of the results are controversial, a recommendation based on scientific evidence cannot be made at this time. At the best estimate - but that is all it can be - only among those who have sexual intercourse 10 hours prior, and are accustomed to it, it has no effect whatsoever. Some studies even underline the importance for athletes to keep their sexual habits constant. However, some coaches recommend abstinence, with no published scientific evidence to date.

It is clear that up to this point, evidence is controversial. We still do not know exactly what the best recommendation would be for athletes as there is insufficient data on the effects on performance variables. More studies are needed so that medical recommendations can be based on scientific evidence, thus encompassing health and performance.