Stronger People Have More Sex Partners—And Science Wants You to Know About It

Monday, February 10, 2025

For centuries, humanity has debated what makes someone irresistible. Is it charm? Intelligence? The ability to make a perfect cup of coffee at 7 a.m. without speaking a word?

Well, science is here to rain on the poetry parade with a firm, evidence-based conclusion: it’s strength.

According to a new study published in Evolution and Human Behavior, people with stronger upper bodies tend to have more sexual partners over their lifetimes.

Men with superior grip strength were not only more likely to have more romantic partners but also more likely to be in long-term, committed relationships.

Women with stronger upper bodies? Same deal—more partners overall.

Yes, folks. The humble hand grip, that unsung hero of physical fitness, might just be one of the biggest predictors of mating success.

Forget the six-pack and the chiseled jawline—the ability to squeeze stuff really hard is apparently the secret to life long love.

Why Strength Still Matters in the Age of Dating Apps

The researchers behind this study, Caroline B. Smith and Edward H. Hagen, weren’t just flexing for fun.

They wanted to explore an age-old evolutionary hypothesis: Did physical strength evolve because it gave men a competitive advantage in securing mates? And more importantly, does it still matter today, in a world where we fight more with emails than with spears?

Their research suggests the answer is a resounding yes—but with a twist.

Using data from a nationally representative sample of over 4,300 American adults (thank you, Centers for Disease Control and Prevention), the team analyzed grip strength as a proxy for overall upper-body power.

Participants also filled out questionnaires about their sexual history, relationship status, and other relevant life details (like health, mood, education, and whether they’re a gym rat or a couch connoisseur).

The results were clear: men who were physically stronger were not just more likely to be in long-term relationships but also reported having more sexual partners throughout their lives.

This challenges some old-school evolutionary thinking that framed male strength mostly as a tool for male-male competition (i.e., I can fight you for this mate and win). Instead, researchers suggest that strength may have been attractive to women because stronger men could provide protection and resources, making them solid long-term investment material.

Women didn’t just want a dude who could punch a saber-tooth tiger—they wanted one who could also bring home dinner.

Wait—What About Strong Women?

Now here’s where things get even more interesting.

The study found that women with greater upper-body strength also reported more lifetime sexual partners.

This is where traditional evolutionary theories start sweating. Classic sexual selection models focus on men’s strength being the primary factor in mate competition. But why would stronger women also have more partners?

Theories, Speculations, and Sophisticated Wild-Ass Guesses

• Stronger women might be more selective.

  • Maybe being physically stronger leads to higher confidence, which makes them more likely to date around before committing.

• Stronger women might pair with stronger men.

  • If strong men have more partners, and strong women are attracted to strong men, this might increase the number of partners reported by strong women as well.

• Strength correlates with an active lifestyle.

  • It’s possible that women who invest in strength training also lead more socially active, adventurous lives, which naturally leads to more opportunities for romantic encounters.

• Maybe strong women just don’t put up with sh*t.

  • If strength is linked to greater independence, maybe stronger women are simply more willing to leave bad relationships and explore new ones. (The weak suffer what they must, the strong date who they want.)

• No matter the reason, this finding flips the old "muscles are just for men" narrative on its head. Turns out, strength is sexy for everyone.

So, Does This Mean We Should All Start Lifting?

Not necessarily. Before you rush to the nearest gym and start crushing protein shakes, let’s be clear: correlation is not causation.

Yes, strength was associated with more partners and more committed relationships, but that doesn’t mean that getting stronger will automatically make you a magnet for romance.

The researchers acknowledge that other factors could be at play, such as personality traits that correlate with physical strength, like confidence, discipline, and an active lifestyle.

Plus, in our modern industrialized world, having more sexual partners doesn’t necessarily translate to greater reproductive success—thank you, birth control.

Where Do We Go From Here?

The researchers are now looking at cross-cultural comparisons to see if the patterns they found hold up in societies where men’s physical strength still directly translates into survival advantages.

They also want to investigate why strength and sexual behavior are linked for women, since the usual explanations of male competition don’t quite fit.

One of the biggest unanswered questions is causality.

Does being stronger actually lead to more relationship success, or is it that people who have more romantic success also tend to be more physically active and strong? Chicken, meet egg.

Final Thoughts: Should You Work on Your Grip Strength?

At the end of the day, there’s something oddly poetic about the idea that the ability to grip something tightly correlates with holding onto relationships. Maybe there's a metaphor in there somewhere—one about strength, endurance, and love requiring both power and control.

Or maybe, as science suggests, it’s just that strong people have an easier time lifting things—including each other.

Either way, it’s good news for those of us who have been meaning to hit the gym. Because if this study is right, strength isn’t just about lifting weights—it might just be about lifting your chances of love.

Be Well, Stay Kind, and Godspeed.

References

Smith, C. B., & Hagen, E. H. (2025). Strength, mating success, and immune and nutritional costs in a population sample of US women and men: A registered report. Evolution and Human Behavior.