Having sex the night before a battery of physical tests does not seem to help or hurt athletic performance, according to two new preliminary studies.

“I knew some people that completed their master’s theses on the topic but could not get it their studies published or had no motivation or desire to do so. I thought that this was a disservice to the scientific community that difficult studies such as this one would remain unnoticed by being unpublished,” the author of the studies told PsyPost.

“Thus, I was able to help get the study published by writing the full manuscript, re-analyzing their data and being proactive. For this particular study, the data was from a 2011 master’s thesis.”

In one study, published in Sexual Medicine, a woman and seven men underwent several physical performance tests on three different mornings. One morning, the participants had sexual intercourse the previous night. On another morning, they did not have sexual intercourse on the previous night, and on another, they completed 15 minutes of yoga the night before.

“We failed to see meaningful changes in any physical performance measure between sexual activity and abstinence conditions. That is, sexual activity the night before a physical performance test does not seem to affect athletic performance,” the researcher explained.

“What is interesting about this study is that we included a third condition, yoga, where the same amount of calories was expended as the sexual activity condition to tease out if it was the calories expended that affected physical performance or something about the sex itself that affected physical performance. Of course, in the end, we failed to show any significant change in physical performance between all three conditions.”

A similar study of ten men, published The Journal of Sports Medicine and Physical Fitness, found that sexual activity had no effect on physical performance tests after five days of abstinence.

“The study was actually conducted in 1986 as a master’s thesis, but I was able to write a full manuscript and get it published over the last few months. Essentially, we also failed to show a significant difference in physical performance measures between sexual activity and abstinence conditions,” the author of the studies told PsyPost.

There have been four other studies — going back to 1968 — that have examined whether sexual activity can impact athletic performance. None have found a significant effect.

But the studies — like all research — include some limitations. For one, the nature of the research makes it harder to recruit participants.

“Some issues with these type of studies including this study are: (1) that almost all males were used. We don’t know how females would respond. (2) these studies examine laboratory-based physical performance tests, but not actual field-based athletic performance measures. We need to generate studies that measure actual athletic performance such as time to run a certain distance, or swimming times over a certain distance, etc.

“(3) most studies in the literature on this topic have small sample sizes; studies should increase its sample size if possible. (4) these studies are crossover studies, where the control group and experimental group are the same subjects. This may pose some issues as the experimental trial (sexual activity trial) may contaminate the results of the control (abstinence) trials. An adequate wash-out period (about 1 week) should occur between conditions.

“(5) it is not known if sexual activity just prior to exercise affects performance (i.e. within 30 minutes of exercise). Most of these published studies had subject sleep 8 hours before the performance measures. ”