Miski Dahir, Ottawa ON — As summer has come in full swing, we tend to sleep at odd times due to the change in our daily schedules. Looking at sleep, it’s an interesting phenomenon. No one knows exactly why we need to sleep despite the fact we spend a third of our lives doing it. We feel tired if we don’t get enough of it. Interestingly, we can also feel groggy if we get too much sleep. Regardless of all the mystery surrounding sleep, it’s very obvious that we need good quality sleep to function throughout the day.  “Good quality” is the key. While we can aim for the magic 7-8 hours of sleep, it’s possible to hit the magic number and still feel groggy the next morning. On the contrary, it’s also possible to get less than the recommended amount of sleep and still feel energized (though long term sleep deprivation can have some serious implications on your health). What are some things you can do to improve your quality of sleep?

 

1.   Put away the phone! Even if it’s “just to do work”. In a study conducted by Klodiana Lanaj et al (2014), 82 mid to high level managers enrolled in MBA classes were recruited. Participants were asked to recorded their cell phone use the night before, sleep quantity, sleep quality, how depleted they felt at work, and how engaged they were at work. Participants completed these surveys for a period of 10 work days. Researchers found that cell phone use late at night was correlated with low sleep quantity at night. Sleep quantity was further negatively correlated to depletion (the less sleep participants were able to get, the more depleted they felt at work the following morning). Feeling depleted at work further reduced work engagement. By putting away your phone at night, you can potentially get more sleep, feel less tired in the morning, and work better.
2.    Just as it can be hard to focus with a lot of noise around you, it can be difficult to fall asleep with noise as well. Try to minimize the level of noise around you. Your body still responds to environmental stimuli even when you are asleep. Hearing sound while asleep (or trying to fall asleep) can decrease your quality of sleep. Sound that are 45 dB (a little higher than the sound you would hear at a library) and above can increase the time it takes to fall asleep by as much as 20 minutes (Muzet, 2007). Many sleep studies also show that noise disturbances during sleep result in less slow wave sleep (also known as deep sleep) and REM sleep (the sleep stage where dreaming occurs) (Muzet, 2007). The World Health Organizations recommends 45 dB as the maximum level of noise inside your bedroom.
3.   Try to minimize the amount of light you are exposed to closer to bedtime and while you are asleep. Light is detected in the eyes by the retina, a structure in the back of the eye. This information is sent to the brain via projections from retinal ganglion cells. One brain region these retinal ganglion cells project to is the suprachiasmatic nucleus (SCN). The SCN is the brain region that controls circadian rhythm (your sleep-wake cycle) and is considered a circadian pacemaker. This brain area has several other downstream targets which are important for the regulation of sleep such as the ventral preoptic area and the lateral hypothalamus. The amount of time we spend asleep is determined by our circadian machinery (LeGates, 2014). Due to this system we have in place, artificial light at night can have profound effects on sleep such as delaying our circadian rhythm and preferred sleep time.   
4.   Exercise! Not only does exercising comes with a lot of physical and mental health benefits, it can also help with sleep. In a study conducted by Gerber et al (2014), 42 students (of which 22 agreed to undergo sleep-EEG recordings) were recruited. Physical activity of the students along with subjective sleep complaints and objective sleep patterns were recorded. Participants who engaged in physical activity reported less sleep complaints. Furthermore, participants who met the American College of Sports Medicine’s vigorous physical activity guidelines (vigorous physical activity for 20 minutes for 3 days a week) slept up to 45 minutes longer. These participants also presented more slow wave and REM sleep. They also had lower percentage of light sleep. Vigorous physical activity is defined by the World Health Organization as requiring “a large amount of effort and causes rapid breathing and a substantial increase in heart rate”. Some examples of vigorous physical activity include running, swimming, fast cycling, and competitive sports. There are many speculated reasons why exercise may improve sleep quality. One reason may be that that exercise results in the secretion of growth hormones. Growth hormone secretion is regulated by other hormones like GHRH (growth hormone releasing hormone) and ghrelin, both of which have been shown to promote sleep and increase slow-wave sleep respectively (Steiger, 2007).  On the other hand, it could just be that people who engage in vigorous physical activity lead more structured lives (as they need to incorporate exercise into their day) and as a result have a more structured sleep/wake pattern.

For more reading check out the resources used to create this article:

Muzet. (2007). Environmental noise, sleep and health. Sleep Med. Rev., 11, 135-142

Steiger (2007). Neurochemical regulation of sleep. J Psychiatr Res, 41, 537-552

Lanaj, K.; Johnson, R.E.; Barnes, C.M. (2014). Beginning the workday yet already depleted? Consequences of late-night smartphone use and sleep. Organ. Behav. Hum. Decis. Process, 124, 11–23.

LeGates, T. A., Fernandez, D. C., & Hattar, S. (2014). Light as a central modulator of circadian rhythms, sleep and affect. Nature Reviews. Neuroscience, 15(7), 443–454.

Gerber, S. Brand, C. Herrmann, F. Colledge, E. Holsboer-Trachsler, U. Pühse. (2014). Increased objectively assessed vigorous-intensity exercise is associated with reduced stress, increased mental health and good objective and subjective sleep in young adults. Physiol. Behav., 135, 17-24