The quality of sleep does not depend only on the number of hours we stay asleep, but on the time we spend in each of the sleep phases, which alternate throughout the night. Our lifestyle directly influences rest habits and now a study has revealed that physical activity prolongs REM sleep latency, that is, the time necessary to reach the REM phase of sleep.
This suggests that exercise helps consolidate the deeper phases of sleep before entering REM sleep, at which time we experience vivid dreams and our brain activity is similar to what we have when we are awake. The research has been conducted by scientists at the University of Texas at Austin and has provided the most reliable validation to date of the relationship between physical activity, sleep quality and psychological health.
There are scientific studies supported by anecdotal evidence that already showed that exercising regularly improves the quality of sleep. And, the better we sleep, the better our mood. Despite the abundant scientific evidence supporting these claims, until now studies have been conducted in laboratory settings, basing their conclusions on the observation of experiences after a single night of sleep. These limited methodologies represent a problem for any scientific study, regardless of the acceptance of its findings.
“A lot can be learned from laboratory studies, but there are obviously limitations to studying participants’ sleep patterns on a single night,” said Benjamin Baird, research assistant professor of psychology and one of the study’s authors. “It is an unfamiliar, clinical-type environment, which can be stressful. And it cannot be observed over time either. So there are always questions about the generalization of that type of design.”
Impact of daily activities on sleep and mood
The authors of the new study examined how daily physical activity patterns influence sleep phases and emotional well-being in a natural environment – at home, at work and during daily activities – over several months. Their findings have been published in Nature Scientific Reports.
To do this, they used advanced wearable technology to monitor sleep and activity levels in 82 young adults. A wrist-worn activity tracker recorded both movement and heart rate. From these signals, periods of deep (NREM) and REM sleep could be determined, along with physical activity. A smartphone application was used to collect self-reported well-being data.
This study originated from a pilot study conducted as part of Whole Communities–Whole Health, a large research program that takes an interdisciplinary approach to how healthcare data is collected, while engaging communities and to the participants in the research process. This larger study successfully replicated many of the findings previously conducted in sleep laboratories: specifically, that engaging in both low-intensity physical activity and moderate-to-vigorous physical activity was linked to deeper, more restorative sleep, and that better Sleep, in turn, was associated with more energy and less stress the next morning.
Differences in sleep architecture – the three stages of non-REM sleep (light, deep and deeper sleep) and REM sleep – are associated with people’s perceived well-being
The main difference this time was the researchers’ innovative use of wearable technology, which allowed for continuous monitoring of participants’ behaviors, providing a complete picture of daily activities and their impact on sleep and state of mind. mood for several weeks, even months.
Baird noted that for the first time, researchers were able to address how these differences in sleep architecture are associated with people’s perceived well-being. Sleep architecture refers to the structure of each 90- to 120-minute sleep cycle: the three stages of non-REM sleep (light, deep, and deeper sleep) and REM sleep, which makes up the last 25% or so of each. cycle.
“We’ve shown this using a standard Fitbit that anyone could wear – it’s not even an expensive scientific device – that is sensitive to these measures of sleep architecture, in a way that shows predictive results,” said co-author David M. Schnyer. and president of the Department of Psychology.
“The world is your oyster now. You can use this device to study all kinds of different data about lifestyle-related sleep architecture – related to mood and mood disorders – in the field, not in a lab, which was previously done. I thought it was not possible,” concludes the researcher.