Handshakes lasting longer than three seconds can trigger anxiety, negatively impact business meetings and affect the state of our relationships according to a new study out of Scotland.
Thirty-six participants were interviewed by masters students at the University of Dundee's school of social sciences about their work and career prospects.
They were then introduced to a second researcher, who would either shake their hand as "normal" (less than three seconds), "prolonged" (longer than three seconds), or not at all.
The participants were unaware of the significance of the handshake throughout the study period, with their subsequent reactions analysed.
Dr Emese Nagy, a reader in psychology who led the study, said the findings highlight the importance of introducing ourselves appropriately.
"Handshakes are a particularly important greeting and can have long-lasting consequences for the relationships that we form," she said.
"There has been evidence to suggest that many behaviours, such as hugs, fall within a window of approximately three seconds and this study has confirmed that handshakes that occur in this time frame feel more natural to those who participate in the greeting.
"While shaking hands for longer may appear to be a warm gesture on the surface, we found that they negatively affected the behaviour of the recipient, even after the handshake was finished."
Nagy said politicians are particularly keen on prolonged handshakes, which are often used an expression of warmth but also as a means of demonstrating authority.
"However, our findings suggest that while doing so might look impressive for the cameras, this behaviour could potentially jeopardise the quality of their working and personal relationships from the beginning, which could have repercussions for millions of people."
The team found participants showed less interactional enjoyment after the longer handshake, laughing less and showing increased anxiety.
Handshakes lasting less than three seconds resulted in less subsequent smiling, but did feel more natural to those who participated.
No behavioural changes were associated with the no-handshake control experiment.
The results can be found in the Perceptual And Motor Skills journal, Effects Of Handshake Duration On Other Nonverbal Behaviour.
Previously in 2011 Dr Nagy analysed hugs and what they say about shared experiences.
Australian Associated Press