By: Kimberly Rodrigues
Humans need a sufficient amount of high-quality sleep to maintain their physical and mental health. For instance, getting enough quality sleep can help treat a number of conditions, such as dementia, mental illness, and metabolic, cardiovascular, and metabolic disorders. On the other hand, sleep disorders like insomnia, narcolepsy, and excessive drowsiness are very common all over the world and may cause major health problems.
50 to 70 million adult Americans suffer from sleep disorders, particularly insomnia. Meanwhile, a meta-analysis of 17 researchers found that 15 per cent of people in China suffer from sleeplessness. It’s crucial to research the elements that support high-quality sleep in order to comprehend such conditions better. According to earlier studies, leading a healthy lifestyle that includes eating well and exercising frequently is beneficial.
Previous studies have indicated that a proper lifestyle, including a healthy diet and regular physical activity, is beneficial for good sleep. However, a systematic comprehensive study 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 Japan Advanced Institute of Science and Technology (JAIST), who is also an adjunct researcher at the Faculty of Sport Sciences at Waseda University, has probed the inter-relationship between sedentary behaviour, physical activity, and sleep quality in a sample of the middle-aged Japanese population.
The research group, comprising Professor Yukari Nagai, also from JAIST; Professor Akitomo Yasunaga from Bunka Gakuen University; Associate Professor Ai Shibata from the University of Tsukuba; Professor Yung Liao from National Taiwan Normal University; Associate Professor Gavin R. McCormack from the University of Calgary, and Professor Koichiro Oka and Professor Kaori Ishii from Waseda University, based their study on Japanese adults between 40 and 64 years of age — a crucial time window which often marks the onset of various health issues. Their work has been recently published in Scientific Reports.
The researchers used an isotemporal substitution approach, which estimates the effect of replacing one activity type with another for the same amount of time. Dr Koohsari said, “We replaced 60 minutes of sedentary behaviour or light-intensity physical activity with moderate-to-vigorous physical activity in the 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.
The replacement of sedentary behaviour with moderate-to-intense exercise indeed improved sleep quality. Interestingly, this association was seen to be gender-based and was only found in women. This is in agreement with reports that have shed light on gender-based differences in sleep disorders. More studies are, however, required to understand why these gender-based dissimilarities occur.
In summary, this study contributes to the existing pool of studies that provide empirical evidence of the importance of physical activity in promoting good-quality sleep. Hopefully, these studies will serve as a useful platform for further research on the prevention of sleep-related disorders.
Surely, we now have enough motivation for regularising our workout schedules!