By: Ally Bowersock, Ph.D, CSCS, Co-Owner of RunAbout Sports Roanoke
There are only so many hours in the day and the to-do list is forever long. How, then, do you fit everything in? For many people, one solution is to cut back on sleep. For many people, they have no choice but to sacrifice sleep due to family or work obligations, WHEN they work (i.e. shift work), stress, sleep disorders, you name it. Is it REALLY that big of a deal to get as little sleep as possible and still function with some help from our friends called caffeine and other stimulants?
The science of circadian rhythm is a growing field of interest due to these increasingly frequent demands on our time at all hours of the day. Emerging evidence suggests that, in fact, sleep habits impact many facets of our health and, in turn, many facets of our wakeful habits impact our sleep quality and quantity.
Let's just say your sleep quality and quantity are not compromised and you merely change time zones to run a marathon. Is your performance impacted if you allow a few days of time zone acclimation? The answer appears to still be yes! Stanford researchers conducted a retrospective study of NFL Monday Night Football game outcomes when comparing east coast teams vs. west coast teams over a 20-year period. The result: west coast teams won more games and outscored east coast opponents each game by a significant difference among both variables. West coast teams had somewhat of a "home field advantage" when it comes to sleep as playing times more closely aligned with their regular sleep schedule. Such evidence suggests performing an athletic event as close to your natural sleep-wake cycle is a performance-enhancing advantage and/or that circadian rhythm disruption has a deleterious effect on athletic performance (Smith et al, 1997).
Now let's say you're running a race in your regular time zone. However, "life" is impacting your sleep quality and/or quantity. You're stressed about work and find it challenging to both go to sleep or stay asleep, or you easily fall asleep but then wake frequently throughout the night. Your alarm clock goes off and you feel sluggish, irritable, still stressed. Is there an impact on your overall health? Again, evidence points to yes. A recent study in the journal Current Biology suggests that even when people attempt to "catch up" on sleep on weekends, eating patterns (especially after dinner) are negatively influenced and insulin sensitivity is reduced (Depner et al, 2019). What does this mean for everyday folks trying to stay healthy or maybe lose weight? It means that poor or disruptive sleep not only increases hormone secretion which stimulates appetite but these hormones are increased later in the evening when the sleep-wake cycle is headed downward toward sleep and metabolism begins to slow. A lower metabolic rate coupled with a reduced insulin sensitivity will at minimum reduce the likelihood you go to sleep satiated and ready for sleep and, more likely, increase chances that you eat a greater volume of calories than you would otherwise want or need. If you are diabetic, the effects on insulin are even more harmful.
So, you know that being physically active and, in particular, building lean muscle mass, can help improve overall health. Does being active protect against poor sleep habits? The answer is: it depends. An emerging subset of circadian rhythm research is investigating "sleep inertia", or that is, how long it takes a person to reach a fully wakeful and alert state upon waking from sleep. There are certain professions like medicine and emergency response personnel which require full alertness upon waking in order to respond to emergency or perform tedious surgical tasks. Even with adopting healthy lifestyle habits like being physically active, evidence suggests sleep inertia varies drastically between individuals and some people may take up to twenty minutes for a fully wakeful state (Wertz et al, 2006). Impaired cognition as a result of slow sleep inertia could, then, have significant consequences both on the health of the individual as well as performance at work!
If you cannot change your work schedule or life stressors chipping away at your sleep quality, how do you improve your sleep? Rather than trying to completely overhaul your life, research suggests start with small consistent changes. For example, try to minimize the volume of sleep disruptions which may cause you to wake frequently. Remove electronics except for an alarm clock out of your bedroom as these devices emit light which can negatively impact sleep. If you must keep a phone in your room, place it face down and set a "do not disturb" range so that email and text alerts will not come through at all for a certain span of time. By starting here and minimizing disruptions to your normal sleep cycle, you are able to improve the quality of what sleep you are able to get. If sleep disruption is not an issue but rather you find it difficult to fall asleep, try starting your evening routine earlier in the evening and avoiding eating or drinking anything other than water after a certain time at night. Consider quiet activities like reading a physical book which calm your mind and your breath as well as remove the electronic light which can impact sleep.
Sleep may seem frivolous to some but, as you can see, sleep is critical for performance as well as overall health. If you try a few of these tips and still are not improving your sleep, consider seeking attention through your healthcare provider. Sleep should be prioritized in order for the rest of your wakeful time to be of greater quality. Being fit, healthy, and happy are much more realistic when you can get those zzzzz's!
Depner et al. 2019. Ad libitum Weekend Recovery Sleep Fails to Prevent Metabolic Dysregulation during a Repeating Pattern of Insufficient Sleep and Weekend Recovery Sleep. Current Biology, 29(6), 957-967. Cited from: https://www.cell.com/current-biology/pdfExtended/S0960-9822(19)30098-3
Smith et al. 1997. Sports, Sleep, and Circadian Rhythm. Sleep, 20(5), 362-365.
Wertz et al. 2006. Effects of Sleep Inertia on Cognition. JAMA 295(2), 159-164. Cited from: https://jamanetwork.com/journals/jama/article-abstract/202171