Holding and walking for five minutes calms crying baby, study says

Science has perfected the answer to calming a crying baby: hold and walk with him for five minutes. The relaxing, evidence-based strategy emerged from experiments carried out in Japan and Italy, which were analyzed and published in the journal Current Biology on Tuesday (13).

The paper’s authors hope the finding could benefit stressed parents, especially inexperienced ones.

“I raised four children,” the study’s lead author, Kumi Kuroda, from the Riken Center for Brain Science in Japan, said in a video. “But I myself didn’t predict the main results of this study until the statistical data came out,” she added.

Previously, the team had studied the “transport response” in mammals that give birth to young that cannot fend for themselves, such as mice, dogs, monkeys and humans. When these animals pick up their young and start walking, the little ones are calm and docile, and their heart rate slows.

Kuroda and his colleagues wanted to explore this further in humans and compare the effect to other comforting behaviors, such as rocking without walking. They recruited 21 pairs of mothers and babies aged 0 to 7 months and tested them in four situations: carried on the move, on their mothers’ laps sitting, lying in a stationary crib or lying in a rocking crib.

Crying and heart rate decreased by 30 seconds when babies were carried. There was a similar effect when they were swung, but not when they were held still. This suggests that, contrary to what might be assumed, the maternal load was insufficient to calm the child and the transport response was an important factor.

They then analyzed the impact of holding the baby for five minutes and found that the activity made 46% of them fall asleep and another 18% fall asleep the next minute.

This showed that holding them not only stopped them from crying but also promoted sleep.
But with one problem: when babies were placed in their cribs, more than a third were alert within 20 seconds.

Electrocardiogram readings showed that the babies’ heartbeats increased the moment they were separated from their mothers’ bodies. However, when babies slept for a longer period of time before being placed in their crib, they were less likely to wake up.

Kuroda said he was surprised by the results as he had assumed that other factors, such as the way or position in which they were placed in the crib, would play a more important role, but that was not the case. “Our intuition is very limited, so we need science,” he said.

Based on the totality of the findings, they recommended a protocol to promote peaceful sleep: hold the baby and walk with him for five minutes and then sit and hold for another five to eight minutes before putting him to sleep.

Unlike other methods, such as letting the baby cry itself to sleep, this provides a comfortable environment, but more work will be needed to understand whether it can condition infant sleep in the long term.