Will Sex Before a Competition Hamper Your Performance? And How Estrogen, Cortisol, Quail and Muhammad Ali Could Help Us Answer This Existential Question

Image 1: At least in his later life, Muhammad Ali could hardly be considered a "bro". Notwithstanding, he was 100% convinced that having sex the night before a fight was a total no-go.

I you are a bro, or frequent one or many of the pertinent boards, the question whether or not sexual intercourse with yourself or your partner will have beneficial, neutral or negative effects on your performance in the gym, and more importantly your gains and endocrine system probably is not news to you. Even in case you do not belong to either of the former categories, I am sure you will have heard about Olympians or other athletes refraining from the previously mentioned exchange of bodily fluids on the day, if not during the whole week, let alone weeks before a competition. Now, as chance would have it, I stumbled across an interesting study that was conducted by a group of researchers at the University of Liege in Belgium (it goes without saying that Liege is in Wallonia, the French-speaking part of Belgium, right? ;-) that may not be able to provide direct evidence for or against pre-competition sex, but could at least help us to shed some allegedly dim light on the hormonal changes that occur in your brain, when birds and bees finally meet (Dickens. 2012).

Of the birds and the bees and how stressing the best things in life can become

To study the effects of stress and sexual intercourse on neural aromatase (remember: the enzyme that converts testosterone into estrogen) and circulating stress hormones Molly J. Dickens and her colleagues from the Research Group in Behavioural Neuroendocrinology picked a very exotic model: The common quail. Now, despite the undeniable differences that (hopefully) exist between your sexual partner of choice and these shrunken chickens, birds, in general, and quails in particular have a long history as a supposedly accurate model for systemic effects of hormonal changes at the cerebral level and have been used, among other things to elucidate hormonal effects on appetite and food intake (Balthazard. 1998).

Significant other advisory: Don't take today's news so serious that you ruin your partnership. This is one of the SuppVersity posts with at least as much entertainment as informative value ;-)

The researches tested the nuclei-specific aromatase activity changes, the corresponding observable behavior, subsequent fertilisation rates and corticosterone (cortisol) concentrations of quail in a relaxed, non-stressed or an acutely stressed (15 min restraint) immediately prior to sexual interaction (5 min) with stressed or non-stressed partners. Quite a complex undertaking, and in all honesty nothing I want to think about for longer than by any means necessary, so let's get straight down to the nitty gritty ;-)

Figure 1: Cortisol levels in stressed and non-stressed male and female quail before (baseline) and after intercourse with a stressed or non-stressed partner (data adapted from Dickens. 2012)

As you can see in figure 1 the cortisol response of birds and bees, ah... pardon, male and female quail in stressed + non-stressed, stressed + stressed, non-stressed + non-stressed and non-stressed + stressed pairings was very differential. let's briefly go through some very realistic *rofl* scenarios, say you are a...

• Male weight lifter right before competition - In this case your baseline cortisol would be high (stressed), what would you do to keep that in check? Right you would have sexual intercourse with your hopefully totally relaxed girlfriend / wife. The stress reduction would be meager, but alas... there are different reasons to engage in this utterly human act (and did I mention that it is 100% paleo?)
• Male student who trains just for fun - Assuming that you are one of the slackers whose parents finance their studies (don't deny it, I know you, guys!) and who spend most of their time in the gym hitting on the girls, you better stick to just hitting on them, if you don't want to quintuple your stress levels. Although, let's be honest, the reasons you are not seeing any gains are probably not related to high cortisol levels, anyways ;-)
• Female 200m runner right before competition - With the big day right ahead your cortisol levels are skyrocketing, the worst thing you could do now, is make out with one of your male colleagues who is likewise totally stressed out. You better go home to your loving boyfriend or husband and spend some cozy hours with him to reduce your stress levels by -44% and decrease your not chance to jump the gun.
• Female leisure time gymrat: You are calm, you know you are sexy and have no reason to be stressed out other than your boring, non-stressed boyfriend or husband at home. And  while you would be way better off with the hectic postman (obviously only in terms of stress increases ;-), I am not sure if that could not have very enervating and thus stressing consequences *rofl*

I see, you are questioning the value of the practical advice I am putting out here? Well, let's see what others have to say on the issue, let's take Samantha McGlone and Ian Shrier, for example, in their review of the literature they explicitly mention that despite the fact that (McGlone. 2000):

[...] the results of these studies [there were obviously only three scientific ones published between 1975 and 1989], one might conclude that sexual activity the night before competition would not affect performance. However, each of the above-mentioned studies focused on the physiological effects of precompetition sex, which would only be expected to decrease performance if the activity led to exhaustion. Considering that normal sexual intercourse between married partners expends only 25-50 calories (the energy equivalent of walking up two flights of stairs), it is doubtful that sex the previous night would affect laboratory physiological performance tests. Remembering that the original hypothesis suggested that performance would only be affected through a change in aggression, researchers really should have measured variables that are affected by aggression (e.g., motivation, alertness, and attitude toward competition).

Now this is where brain aromatase activities come into play of which Trainor et al. report in a detailed review of the pertinent literature that "in most cases estrogen [in the brain!] increases the probability and intensity that males will engage in aggressive behavior" (Trainor. 2006) - surprised, right?

Brain aromatase, estrogen and the crunch question: "Sex or no sex before a competition?"

Now, what does that mean in view of the finding that the stress induced increase in aromatase activity was immediately reversed in the male quail (the changes in the female quail were less consistent)? I guess, it means Muhammad Ali who always insisted that sexual abstinence before an event was an absolute must was right - at least in a sport such as boxing which certainly depends on a decent level of aggression you do not want to compromise that by dumping down brain aromatase activity, would you? What? Oh, you would? Well, I guess me, too ;-)

References:

1. Balthazart J, Ball GF. The Japanese quail as a model system for the investigation of steroid-catecholamine interactions mediating appetitive and consummatory aspects of male sexual behavior. Annu Rev Sex Res. 1998;9:96-176.
2. Dickens MJ, Balthazart J, Cornil CA. Brain aromatase and circulating corticosterone are rapidly regulated by combined acute stress and sexual interaction in a sex specific manner. Journal of Neuroendocrinology. 2012. [Epub ahead of print] DOI: 10.1111/j.1365-2826.2012.02340.x
3. McGlone S, Shrier I. Does sex the night before competition decrease performance? Clin J Sport Med. 2000 Oct;10(4):233-4.
4. Trainor BC, Kyomen HH, Marler CA. Estrogenic encounters: how interactions between aromatase and the environment modulate aggression. Front Neuroendocrinol. 2006 Jul;27(2):170-9. Epub 2006 Jan 10.