
Summary: Physical activity improves sleep quality, especially in women, according to a new study.
Source: Japan Higher Institute of Science and Technology
An adequate amount of good quality sleep is essential for human physical and emotional well-being.
For example, good quality sleep helps improve outcomes for various diseases, including cardiovascular and metabolic disorders, mental illness, and dementia. On the other hand, sleep disorders such as insomnia, narcolepsy, and excessive sleepiness can lead to serious health problems and are quite common all over the world.
In the United States, 50 to 70 million adults suffer from sleep disorders, mainly insomnia. Meanwhile, a meta-analysis of 17 studies suggested that in China, insomnia is present in 15% of the population. To better understand these ailments, it is important to study the factors that promote good quality sleep.
Previous studies have indicated that a proper lifestyle, including a healthy diet and regular physical activity, is beneficial for good sleep. However, a comprehensive systematic review is lacking in this area of research.
To this end, a team of researchers from Japan, Canada and Taiwan, led by Associate Professor Javad Koohsari from the School of Knowledge Science at the Japan Advanced Institute of Science and Technology (JAIST), who is also an Adjunct Researcher at the Faculty of Sports Sciences at Waseda University, probed the interrelation between sedentary behavior, physical activity and sleep quality in a sample of the Japanese middle-aged population.
The research group, consisting of Professor Yukari Nagai, also from JAIST; Professor Akitomo Yasunaga of Bunka Gakuen University; Associate Professor Ai Shibata of the University of Tsukuba; Professor Yung Liao of National Taiwan Normal University; Associate Professor Gavin R. McCormack of the University of Calgary and Professor Koichiro Oka and Professor Kaori Ishii of Waseda University based their study on Japanese adults between the ages of 40 and 64, a crucial period that often marks the onset of various health problems. .
Their work was recently published in Scientific reports.
The researchers used an isotemporal substitution approach, which estimates the effect of replacing one type of activity with another for the same amount of time.
According to Dr. Koohsari, “We replaced 60 minutes of sedentary behavior or low-intensity physical activity with moderate-to-vigorous physical activity in participants’ schedules.”

An accelerometer monitored the participants’ level of physical activity for seven consecutive days. A questionnaire was then used to assess the participants’ quality of sleep and rest.
Replacing sedentary behavior with moderate to intense exercise did indeed improve sleep quality. Interestingly, this association was thought to be gender-based and was only found in women. This is consistent with reports that have shed light on gender differences in sleep disorders. Further studies are needed, however, to understand why these sex-based dissimilarities occur.
In summary, this study contributes to the pool of existing studies that provide empirical evidence for the importance of physical activity in promoting good quality sleep. Hopefully, these studies will serve as a useful platform for further research into the prevention of sleep-related disorders. Surely we now have enough motivation to regularize our training schedules!
Funding:
Dr. Gavin R. McCormack is supported by a grant from the Canadian Institutes of Health Research Foundations Program (FDN-154331).
Professor Koichiro Oka is supported by a Scientific Research Grant (No. 20H04113) from the Japan Society for the Promotion of Science.
About this exercise and current sleep research
Author: Mohamed Javad Koohsari
Source: Japan Higher Institute of Science and Technology
Contact: Mohammad Javad Koohsari – Higher Institute of Science and Technology of Japan
Picture: Image is in public domain
Original research: Free access.
“Sedentary behavior and sleep quality” by Mohammad Javad Koohsari et al. Scientific reports
See also

Summary
Sedentary behavior and sleep quality
Quality sleep is an important factor in maintaining health and improving well-being. Previous evidence has demonstrated the positive associations between increased physical activity and reduced sedentary behavior (SB) with sleep quality.
The surrogate relationships between SB, low-intensity physical activity (LPA), and moderate-to-vigorous physical activity (MVPA) should be considered when considering the impact of a particular behavior on quality of sleep.
No study, to our knowledge, has explored these surrogate relationships in adulthood.
Using an isotemporal substitution approach, this study examined the associations of replacing sedentary time with physical activity on measures of sleep quality in a sample of middle-aged adults in Japan. Data from 683 adults aged 40 to 64 living in Japan were used. The average daily time spent in SB, LPA and MVPA was objectively assessed by accelerometers.
Two self-reported measures of sleep quality were obtained using questionnaires, including sleep rest and sleep quality. Multivariable linear regression models were used to assess associations of SB, LPA, and MVPA with measures of sleep quality stratified by gender.
We found that each 60-minute unit of SB or APL replaced with MVPA was favorably associated with sleep rest in women (b= 0.16, 95% CI 0.07, 0.28, p<0.001; b= 0.18, 95% CI 0.07, 0.32, p< 0.05, respectively). There was no significant association between SB, LPA, and MVPA with measures of sleep in men in all three models.
These results indicate that a higher MVPA has a positive association with sleep quality in middle-aged women.