[Austin Both is the Associate Performance Director of Athletic Lab]
Although we are all experienced sleepers, that does not mean we are all proficient at the skill of sleeping. Very few of us place conscious thought into our sleeping habits beyond the goal of not being utterly exhausted the next day. As a result, we are missing out on a superpower for health, recovery, and vitality. Getting adequate sleep in the form of quality and quantity can improve immune function, vigor and energy, as well as improved gains in athletic endeavors (WebMd). Unfortunately, poor sleep can have the exact opposite effect.
First, to lay the foundation, let us discuss what optimal sleep looks like in a general sense. We often hear that 8 hours should be our goal each night; however, this value is not always practical, nor does it take into account variance from individual to individual. An acceptable bandwidth could be considered anywhere from 6-10 hours, but each person will likely have their own sweet spot that must be determined. Furthermore, quality of the sleep is a vital variable to consider. In its simplest sense, high quality sleep consists of falling asleep relatively quickly, followed by minimal restlessness throughout the night. On a deeper level, high quality sleep should follow an uninterrupted cyclical nature that flows between varying stages of light, deep, and REM sleep (INSEP, Hausswirth, Mujika, p.100).
The effect of sleep deprivation on exercise performance has been quite extensively researched, and the results strongly indicate a nearly unanimous negative effect. Sleep deprivation could be considered anything as little as a 2-hour disruption. A more complex identification of deprivation could also include a disruption in the quality of sleep marked by restlessness throughout the night as well as a disruption of the cyclic nature of your sleep cycles. Even these minor values of sleep deprivation have been associated with faster time to exhaustion, increased heart rate during submaximal exercise, reduced force outputs, slower sprint times, and more rapid strength declines within a session (INSEP, Hausswirth, Mujika, p.104). Although this list is nowhere near conclusive, it still provides insight nearly every relevant domain of performance related fitness. As such, whether we are looking at a typical weekend warrior, or elite level athlete, if you are not sleeping well, you are not performing anywhere near the peak of your capability.
In addition to the physical decrements of non-optimal sleep, there are a host of cognitive factors at play as well. It is relatively obvious, anecdotally, that poor sleep causes us to feel foggy or sluggish, but this domain is also relatively well documented within the literature. Even acute sleep deprivation resulting from one night of interrupted or shortened sleep duration can have negative effects of attention, short term memory, and long-term memory. Researchers across numerous studies were able to associate acute sleep deprivation with impairments in reaction time, dual task attention, working memory, and decision making to name a few (Alhola & Polo-Kantola, 2007). While some of the tests reported in this analysis were reported as ‘no change,’ a majority saw reductions in performance on the related task, while not a single one reported improvements.
While everyone reading this article is likely active and fit, we may not all be elite athletes. As such, boosting physical performance to your peak potential may not convince you that optimizing sleep is important. Noting the dramatic effects on cognitive performance; however, should be absolutely important to us all. Whether it is in daily personal life, professional life, or during physical activity, cognitive performance is paramount. Next in this series, I will discuss sleep and its relationship with immune function, the physiological factors involved in sleep, and most importantly, simple practical fixes we can all practice to take advantage of this information.
- Alhola, P., & Polo-Kantola, P. (2007). Sleep deprivation: Impact on cognitive performance. Neuropsychiatric disease and treatment, 3(5), 553-567.
- Institut National du Sport, de l’Expertise et de la Performance (INSEP), Hausswirth, C., Mujika, I. (2013). Recovery for performance in sport. Champaign, IL: Human Kinetics.
- Surprising Reasons to Get More Sleep. (n.d.) WebMd. Retrieved on May 09, 2020 from https://www.webmd.com/sleep-disorders/benefits-sleep-more#1