You'd be forgiven for thinking that we humans do nothing but talk about sex.

But even when us amorous apes actually stop doing the jaw-jaw and get down to business, there's still one question haunting our horny brains: just how long should sex last?

If you're Sting or Puff Daddy, you'd probably say sex should go on for at least the length of a bank holiday weekend.

Whilst if you're an inexperienced spotty teenager, you'll probably be delighted if the time taken to complete a dirty deed matches the duration of an average Ariana Grande tune.

Now science has weighed in (again) to tell the world exactly how much time they should be spending in the act of physical love: 5.4 minutes.

"If you're a non-scientist, you might have once asked yourself, propped against the bedhead after disappointingly quick intercourse, how long does sex 'normally' last?" Dr Brendan Zietsch from the University of Queensland wrote in The Conversation.

"A scientist, though, would phrase the same question in an almost comically obscure way: What is the mean intravaginal ejaculation latency time?

"I know there's a lot more to sex than putting the penis into the vagina and ejaculating, but the rest is not always easy to define (kissing? rubbing? grinding?).

"To keep things simple and specific, we'll just focus on the time to ejaculation."

Dr Brendan Zietsch recounted a study in which 500 couples were armed with a stopwatch and asked to press the button (of the clock) when the unspeakable act begun and then tap it again when the man experiences his magical moment.

"That is as practically awkward as it sounds: participants pressed 'start' at penile penetration and 'stop' at ejaculation," he added.

"You may note this could affect the mood somewhat, and might perhaps not exactly reflect the natural flow of things.

"But science is rarely perfect, and this is the best we've got."

This study found that sexy time lasts anywhere between 33 seconds and 44 minutes, with the median time coming in at 5.4 minutes.

Interestingly, the research also explores "conventional wisdom regarding penile sensitivity and its relationship to staying power in the sack".

Older men weren't able to last longer than young ones, while wearing a condom or being circumcised didn't boost chaps' performance either.

"Another surprising finding was that the older the couple, the shorter the sex, contrary to the prevailing wisdom (probably peddled by older men)," Zietsch continued.

Obese men last longer in bed

A study by researchers at Erciyes University in Turkey have found one surprising 'plus' to being severely overweight - and it's your sex life which reaps the benefits.

Titled "Insight on pathogenesis of lifelong premature ejaculation: inverse relationship between lifelong premature ejaculation and obesity," the study's findings seem to point at a correlation between being overweight and stamina.

According to the study, the larger men with more stomach fat and a higher BMI could last for an average of 7.3 minutes in bed.