Study: Does Sex the Night Before Impact Leg Force Output?

Sexual intercourse before an athletic performance or lifting, does it have an impact?

If you watch some of the older Rocky movies, then you may be thinking, “Yeah, Mickey said it does,” but I’m going to go out on a limb here and assume Rocky’s coach didn’t look at the research before making that claim. Also, if you crawl lifting forums or meme pages that populate social media, then it’s not that uncommon to stumble across a “sex” focused post with someone saying something like, “No, honey, I can’t tonight. Tomorrow is leg day.”

Back in September, I wrote an article about the impact sexual intercourse can have on lifting and sport performance. From the research reviewed, I highlighted a few things. First, sexual intercourse is highly variable in how it impacts an individual’s emotional, physical, and mental states. Second, sexual activity often improves performance compared to decreasing it due to other factors that come along with sexual activity (like a boost in confidence, well-being, etc).

The article I wrote is useful, although it had a lot of older sex and performance research, and that’s nice and all, but is it still relevant?

This question brings us to new research published on this topic two weeks ago. In the new study, researchers analyzed how sex pre-performance (12-hours beforehand) influenced leg force production.

Objectives and Participants

The goal of this research was to examine how engaging in sex 12 hours before performance impacted leg muscle force production. Basically, does sex (in most cases, the night before) play a role in how much force our legs can produce the next day?

Researchers took 12 healthy physically trained men, and had them perform five sets of unilateral knee extension and flexion exercises. They analyzed force production using a isokinetic dynamometry machine. Participants completed their five respective sets on an occasion where they had sex 12 hours before, then on an occasion when they abstained.

Outcomes and Practical Takeaways

Researchers found the peak force and torque were similar on both set one and five for the sex beforehand and abstained sessions. They suggest that sexual intercourse the night before (in a short-term setting) isn’t detrimental to force production, or strength training.

This study is great because they use a population that replicates the normal strength athlete, so it’s applicable to those who frequently lift, as opposed to untrained subjects.

There was one caveat with this study, and that’s centered around the fact that the sex the night beforehand was self-reported. In the study’s conclusion researchers write, “However, completion of sexual intercourse was confirmed through self-report rather than direct observation, so it is not certain if participants actually met the requirements of each condition.”

Regardless of whether the men met the sex “requirements” or not, it’s cool seeing more recent research suggest that the notion of sexual intercourse negatively impacting athletic performance is unfounded. What’s most important is to consider how you respond to sexual activity and what it can do to your performance.

Feature image from @lisahaefnerphoto Instagram page.