A hug in the morning for 20 seconds can reduce stress dramatically - but only for women, according to a recent study.

Academics in Germany and the Netherlands carried out the study on "romantic couples" aged between 19 and 32, with men showing no impact post-morning hug.

Speaking on RTÉ's Drivetime, a social psychologist working at Trinity College Dublin said there is a lot of research that hugging is good for a much broader population than the 19-32 cohort tested.

Dr Karen Hand added that it "really helps" people’s parasympathetic system, and "does the same thing to us as meditation, slowing down and breathing".

"It’s very good for our stress levels," Dr Hand said.

Participants in the study were asked to keep one hand in a bucket of ice water for three minutes, while also maintaining silent eye contact.

The women who had received a 20-second hug before having done this had "quite significantly" lower stress levels than those who did not.

Dr Hand cited other studies on the same subject, involving "non-painful or physical" tasks such as public speaking, which found if men and women held hands and then also had a 20 second hug, then men and women experienced lower stress levels.

"It’s good to know there is a general school of research here that is positive for both sexes," she said.

Asked why men did not experience the same response as women when it came to the hugs, Dr Hand said it was not known why, adding that the researchers involved want to explore this further.

Asked if the length of the hug or time of the hug was important, Dr Hand said 20 seconds was "the amount of hug that has been shown I the past to have an effect on men and women".

"The other thing about hugs in general is they have to ideally be from someone we trust, and not from someone we don’t trust," Dr Hand added.

"If somebody were to hug us and we distrust them for whatever reason, this is going to have the opposite effect as if we’re being prayed upon," she said.

Dr Hand said hugs from relatives, as long as they are meant in the right way, would have the same benefit in terms of destressing, although if such hugs "are clingy" they could "be a distress signal".