After a few years of avoiding physical touch, you'd be forgiven if you're feeling a little out of practice. A study to identify the perfect hug is here to help.

According to experiments conducted in the lab and in the real world before the pandemic began, people tend to get the most pleasure from hugs when they last for five or more seconds.

We also tend to give hugs in a criss-cross fashion, where one arm goes over another's shoulder, while the other arm goes under their shoulder. This is opposed to 'neck-waist' hugs, where one person hugs the waist and the other hugs the neck.

In the lab, 'neck-waist' and 'criss-cross' hugs given by a female experimenter were deemed similarly pleasant by 47 female participants. One-second hugs were the least pleasurable, while 5- and 10-second hugs were found to be equally enjoyable.

If you think a 10-second hug sounds like a really long time, you're not alone. The authors of the study were surprised by these results and suspect their participants grew accustomed to the longer hugs over the experiment, although responses to hugs were quite varied.

One participant wrote "feels better every time I must say" in her feedback. Another requested to leave the study partway through the 10-second hug.

In the real world, there's some evidence to suggest a hug lasts about three seconds, so the researchers advise sticking closer to five seconds than 10, as that will probably feel most familiar to people.

"Our findings suggest that longer hugs are more pleasant than very short hugs and criss-cross hugs are more common than neck-waist hugs," the authors conclude.

Unfortunately, the pandemic interrupted a replication of the lab experiment among male participants, so it's not yet clear if this preference for longer hugs exists across sex or gender.

After all, hugging style certainly seems to differ depending on who is giving and receiving the touch. When researchers randomly selected 206 people on a university campus to spontaneously give one another a hug, they found notable differences between male and female participants.

In general, the 'criss-cross' hug was used most often, but this was especially true when the hug was between two male participants. Male-male pairs gave criss-cross hugs 82 percent of the time. Female participants, meanwhile, appeared more willing to go for the 'neck-waist' hug when hugging other females or males.

The findings support previous research from 1995, which also found male-male hugs are done differently from female-female hugs.

In 1999, researchers argued criss-cross hugs were interpreted by huggers as more egalitarian, so the authors of the current study suggest when men hug it could be a way to "express recognition of equality". When women hug, they might be doing it for different reasons.

Still, these are just hypotheses. The current research can only tell us so much, especially since it was conducted in only one culture and among a relatively young age group (between 18 and 43 years of age). The lab experiments were also conducted among only female participants and didn't control for hugging pressure.

There are many questions left to answer about how humans hug and what messages this touch can convey.

In the real world experiment, for instance, height differences didn't play a role in whether someone chose to give a 'neck-waist' hug. That's surprising, as a large height difference can make a criss-cross style of hug more difficult. That said, the biggest gap in height the researchers witnessed was only 20 centimeters.

One of the authors, psychologist Anna Düren, told Science some participants felt the neck-waist hug was more romantic than the criss-cross style, but the findings didn't show this style occurring more often when the two huggers were emotionally close.

For such a staple of human life, there's still a lot we don't know about hugs.

"We anticipate that the studies presented here will provide a foundation for future research on pleasant touch," the authors conclude, "especially for research on hugs, which are highly prevalent but still widely understudied."

The study was published in Acta Psychologica.