Babies fall asleep faster when you hold them while walking, compared with when you hold them in a chair or lay them down
13 September 2022
Scientists have uncovered the most effective technique to soothe a crying baby.
An experiment involving 21 infants aged less than 7 months found they were more likely to stop crying and fall asleep when their mother walked with them, compared with when they were held in a chair or laid in a cot.
“This finding makes sense because when most people pick up a crying baby, they rarely just stand still with them, they instinctively walk around,” says Harriet Hiscock at the Royal Children’s Hospital in Melbourne, Australia.
Kumi Kuroda at the RIKEN Center for Brain Science in Japan and her colleagues became interested in how babies respond to motion after studying the “transport response” in other mammals, in which infants become passive and develop slower heart rates when their mothers carry them.
To test the effect in people, the team monitored 21 crying babies in Japan and Italy while their mothers tried four methods to calm them: holding their baby while walking, moving them back and forth in a pram or rocking cot, holding them while seated and laying them down in a cot.
The experiments, each lasting 5 minutes, were conducted at home or in a laboratory depending on the mother’s preference.
The babies didn’t calm down when their mothers held them while seated or placed them in a cot. But when their mothers walked around with them, they all stopped crying and nearly half of them fell asleep within 5 minutes.
Rocking them in a pram or cot had a similar calming effect, but to a lesser extent. This probably came about due to rocking creating a similar rhythmic motion to walking.
Heart monitors attached to the babies showed that, like other infant mammals, their heart rates slowed when their mother carried them.
Preliminary experiments with fathers showed they also calmed their babies when walking around with them.
This transport response may have evolved so that infants can sleep on their caregivers while they go about their daily business or to keep them quiet if their caregiver spots a predator and needs to carry their baby away without being noticed, says Kuroda.
The researchers advise caregivers who use this walking technique to hold their baby for another 5 to 8 minutes after they fall asleep before putting them in a cot, since the infants in the study tended to wake if they were transferred earlier.
Pamela Douglas at the University of Queensland and Griffith University in Brisbane, Australia, says walking babies around is just one tool to encourage them to sleep. “This study did not include breastfeeding or bottle feeding, which we know are highly effective methods for downregulating little ones to sleep,” she says.
According to Hiscock, the walking technique is useful for babies up to 6 months old, but they should then be encouraged to learn to settle themselves. “You don’t want to have to walk them back to sleep every time they wake up overnight,” she says.
Journal reference: Current Biology, DOI: 10.1016/j.cub.2022.08.041
More on these topics: