- Individuals tend to experience different levels of arousal from day to day, but their average daily level of arousal also differs from other individuals.
- A recent longitudinal study suggests that the previous night’s sleep profile, the previous day’s physical activity, and the nutritional composition of breakfast are associated with daily variations in morning wakefulness levels.
- The study also found that non-genetic factors such as mood, sleep quality, age, and daily food intake frequency predicted differences in morning awakening between individuals.
- This study reported that genetic factors have a modest effect on daily attention, suggesting that interventions that modify non-genetic factors may help improve levels of daily attention. It is suggested that there is
Reduced alertness immediately after waking and during the day can adversely affect cognitive and motor skills and increase safety risks.
A recent study published in
These results suggest that interventions at the individual and societal levels that target these non-genetic factors may help reduce the adverse effects associated with arousal disorders.
While this is a common phenomenon, it can have a significant impact on personal productivity and safety.
Specifically, sleep inertia can affect the safety of workers engaged in hazardous occupations and interfere with the decision-making of emergency personnel, such as medical workers and firefighters, to the safety of others. can affect.
Similarly, poor daytime alertness due to sleep deprivation is associated with decreased productivity and increased risk of road accidents.
However, there is limited scientific evidence on the factors that influence wakefulness levels after waking.
In the present study, researchers evaluated factors associated with daily changes in morning alertness in the same individual.
They also examined the role of genetic and non-genetic factors influencing differences in average morning arousal levels between individuals.
Researchers first examined four prespecified effects.Factors related to day-to-day variation in arousal observed within the same individual.
They assessed the effects of the previous night’s sleep profile, the previous day’s physical activity, the nutritional composition of breakfast, and post-breakfast blood glucose levels on morning wakefulness. I recorded my attention. This study was funded by ZOE Ltd.
To examine the impact of these factors, the researchers used data collected over two weeks from 833 people aged 18-65. Participants were required to wear a wristwatch accelerometer throughout the study period to facilitate the collection of data on sleep profiles and physical activity levels.
To assess their wakefulness level in the morning, participants recorded their alertness level on the app on a scale of 0-100. They reported initial alertness at the start of breakfast and then intermittently over the next 3 hours.
Based on each participant’s baseline sleep profile, researchers found associations between sleep duration and sleep timing and morning wakefulness levels.
Specifically, if participants slept longer than usual or woke up later than usual, they were more likely to exhibit higher levels of alertness the next morning.
Higher levels of physical activity the previous day were also associated with better morning alertness.
Only the most active 10-hour physical activity level of the previous day was positively correlated with morning wakefulness level.
Conversely, nocturnal physical activity was associated with decreased alertness in the morning.
The researchers then examined the effect of breakfast’s macronutrient composition on morning wakefulness. They provided each participant with a calorie-matched standardized breakfast of varying nutritional composition, including a high-carbohydrate, high-protein, and high-fiber diet, which were consumed on different days.
The researchers compared the participants’ levels of alertness after consuming each of these meals to those after a reference meal that provided moderate levels of carbohydrates and protein.
Among the different standardized meals provided to participants, intake of a high-carbohydrate breakfast resulted in higher levels of morning alertness than standard meals.
In contrast, a high-protein breakfast was associated with lower alertness levels than a standard diet.
The researchers also looked at how changes in blood sugar levels after eating breakfast affected wakefulness levels in the morning.
Regardless of breakfast composition, a reduction in postbreakfast glycemic load (a measure of the effect of food intake on blood glucose levels) was associated with increased morning alertness.
Notably, these four factors independently affected morning wakefulness levels.
Jeff Kahn, CEO and co-founder of energy and sleep tracker subscription app Rise Science, who was not involved in the research, commented on the findings: medical news today that:
“This study helps show that positive health and well-being outcomes, in this case improved attention, can be achieved through a variety of means. Four independent and influential inputs they cite — typically Longer sleep duration, exercise in the previous day, a carbohydrate-rich but macronutrient-diverse breakfast composition, and a lower glycemic response in the hours after breakfast are part of our performance toolbox. They are separate tools, and even if you can’t achieve all four all the time, you can benefit from using them.”
Although these factors explain day-to-day differences in morning alertness for the same individual, the authors are also interested in factors that could explain why certain participants had higher average alertness levels than others. I had a
Put another way, researchers were interested in genetic and/or lifestyle factors that might influence individual characteristics and average daytime arousal levels.
Researchers found that positive mood, older age, less frequent daytime eating, and better sleep quality were predictors of an individual’s average daily arousal level.
The current study consisted of both twins and genetically unrelated adults. This allowed the researchers to examine how much genetic factors influence the twins’ daily arousal levels.
Researchers have found that genetic factors have a small impact on an individual’s arousal level, suggesting a greater impact of modifiable lifestyle factors.
Dr. Andrew McHill, a sleep researcher at Oregon Health and Science University, who was not involved in the study, commented:[u]A feature of this current study is the broad range of predictors collected (sleep, diet, activity) and the ability to distinguish between these behavioral and genetic effects using twin studies. ”
“Using this type of analysis, we can more accurately assess modifiable behaviors to improve next-day alertness. It is not only exciting for societal goals, but also for the research community to develop further testable hypotheses for future investigation to identify the precise mechanisms driving these observed changes in arousal. because it provides
The researchers acknowledged that their study had some limitations. For example, morning wakefulness levels in this study were based on self-reports and may be subject to bias.
The study also did not consider differences in morning light exposure, a factor known to significantly increase alertness.
The researchers further noted that all standardized breakfasts consisted of carbohydrates, protein and fat, differing only in the levels of these macronutrients.
They warned that these results should not be taken at face value, leading to adopting a diet consisting entirely of carbohydrates for breakfast.
