How a restless night or a good workout can affect your brain — even days later

Got a lot on your mind to work out? Maybe last week’s workout is to blame.

A new study reports that our brains do not respond to daily life in immediate, isolated bursts — instead, the effects of sleep, exercise, heart rate and mood can linger on our minds for over two weeks.

Researchers from Aalto University and the University of Oulu in Finland tracked a neuroscientist’s brain and behavioral activity for five months, finding that a workout or restless night can influence attention, cognition and memory for several days afterward.

“Our behavior and mental states are constantly shaped by our environment and experiences. Yet, we know little about the response of brain functional connectivity to environmental, physiological and behavioral changes on different timescales, from days to months,” said lead study author Ana Triana, who underwent twice-weekly brain scans, took mood surveys and wore technology that tracked her movements as she went about her daily routine.

From Triana’s data, the team identified two distinct brain response patterns: a short-term wave lasting under seven days and a long-term wave of up to 15 days.

The short wave reflects rapid adaptations, like how poor sleep briefly affects our focus. The long wave suggests more gradual, lasting effects, especially in areas tied to attention and memory. 

Physical activity was also found to positively affect brain region interaction, potentially influencing memory and cognitive flexibility.

Even slight shifts in mood and heart rate left lasting impressions for up to 15 days, the researchers found.

The study revealed a strong tie between heart rate variability — an indication of how well the heart can adapt to changing situations — and brain connectivity, especially during rest.

The team proposes that stress management techniques can shape our brain’s wiring even when we are not actively concentrating on a task.

The findings were published Tuesday in PLOS Biology.

“The use of wearable technology was crucial,” Triana said. “Brain scans are useful tools, but a snapshot of someone lying still for half an hour can only show so much. Our brains do not work in isolation.”

She and her colleagues hope their method of tracking brain changes in real time leads to personalized health care, perhaps helping with the early detection of mental health conditions where subtle signs might be missed.

“We must bring data from daily life into the lab to see the full picture of how our habits shape the brain, but surveys can be tiring and inaccurate,” said study co-author and neuroscientist Dr. Nick Hayward. “Combining concurrent physiology with repeated brain scans in one person is crucial. Our approach gives context to neuroscience and delivers very fine detail to our understanding of the brain.”