As the study authors write, "When a man and a woman are highly synchronous and attuned during a date, their mutual romantic and sexual interest are high as well. This provides evidence that sexual and romantic attraction in humans involve social adjustment of the sympathetic nervous system and motor behaviors."
It's worth noting that these findings were only based on heterosexual couples. And further, it's unclear whether attunement results in attraction, or if attraction boosts attunement.
Either way though, psychologist and study co-author Shir Atzil, Ph.D., says the results indicate that body language is a powerful sign of attraction, if not a catalyst for it. "Connecting with a partner depends on how well we can synchronize our bodies," she says in a news release. "Our research demonstrates that behavioral and physiological synchrony can be a useful mechanism to attract a romantic partner."
So, what does that mean for you, practically speaking?
If you've got a first date coming up, pay attention to your date's body language, and whether you feel you're both "vibing" on the same level. If your date displays engaged body language and you feel a certain resonance in your energies—congrats. You just might have a second date to look forward to.