In a world before alarm clocks and iCalendars, how did we manage to stay on track and wake up on time? Technology continues to get us more connected and the rate at which information travels has increased drastically over the past two decades. So we force ourselves to stay on top of the information stream 24/7.
At some point, you’ve probably felt overwhelmed and “out-of-sync” with your body’s natural rhythm to the point that your cognitive awareness and baseline health has been affected. Five coffees a day isn’t cutting it, cravings become harder to resist, and sleeping patterns — well, let’s not even go there.
Even with our superior mental capabilities, we’re not so different from animals and other living beings. One thing we share in common? The body’s internal clock or circadian rhythm.
Some people have learned to work outside the boundaries of what this internal rhythm was designed to help us do (think overnight shift-workers and international travelers). While it’s not ideal (and barely sustainable) to live like this long term, there are some ways to support your circadian rhythm that might help you feel a little more in tune with yourself.
Editor’s note: The content on BarBend is meant to be informative in nature, but it shouldn’t take the place of advice and/or supervision from a medical professional. The opinions and articles on this site are not intended for use as diagnosis, prevention, and/or treatment of health problems. Speak with your physician if you have any concerns.
What Is the Circadian Rhythm?
Let’s back up for a second and get into what the circadian rhythm is responsible for.
This internal process consists of physical, mental, and behavioral changes that happen cyclically throughout the course of 24 hours. It highly relies on sunlight and other external factors such as temperature and meals to tell the biological systems within our bodies what to do and when to do it.
For example, sleeping at night and staying awake during the day. It’s important to note that while our circadian rhythms and biological clocks are in fact very different from one another, they are very closely related. Our biological clocks are composed of modules at a deeper level of the body responsible for producing the circadian rhythm and leveling it.
While this system is primarily internally regulated and self-sustained, our circadian rhythm is also influenced by environmental factors which can cause involuntary adjustments purely based on habitual routines—regardless of light or temperature.
How Your Circadian Rhythm Affects Your Day-to-Day
Back in the days before lightbulbs and TV screens, we weren’t exposed to as many disruptors. The sun rose, we woke up, and went about our day. Then when the sun went down, we called it in until the next morning. This pattern was quickly challenged after the introduction of electricity and lightbulbs. This new technology emerged around us within just a few decades, and it doesn’t mean our systems evolved along with it. If we didn’t need sleep or sunlight to survive, humans would have adapted accordingly. Since that’s not the case, it’s best to implement healthy habits to support your body’s natural rhythms to avoid burning out.
Decent Sunlight Exposure — The Underdog of Baseline Health
At this point, you’ve probably gathered we are pretty cyclical creatures. In order for us to stay alive and well, we need certain things to happen on a daily basis and at a specific time consistently. One of these being exposure to light.
According to the Sleep Medicine Clinics,
[humans] are most sensitive to light stimuli during the biological night, and far less sensitive to light in the middle of the biological day
Retinas play a big role in the “feeling of awakeness”. Light travels in and sends a signal to your hypothalamus — the central circadian pacemaker for all mammals — and gives it the green light to kickstart every other biological process linked up to this rhythm. For example, the process of digestion.
While this study found minimal effects from night shifts on balancing melatonin (related to sleep quality) and cortisol (related to stress) levels, the more notable differences came from the digestive tract, liver and pancreas. They discovered it “can disrupt certain metabolite rhythms and the peripheral clocks of the digestive system without affecting the brain’s master clock.” (1). If your gut is having a hard time telling you when it’s time to eat, it could well be due to a lack of sleep resulting in poor gut health.
Another factor highly affected by the amount of sunlight you’re exposed to in a day is your mood! Sunnier days bring out happier people, but there’s a little more to it than just the warmth from the rays.
For example, this study’s results showed the impact of blue light exposure on the brain’s actual mechanism after various tests (2). Blue light is the kind that eminates from screens and phones — normally we’re told to limit it, but when we’re exposed to it could play a big difference.
Half of the subjects received specific doses of blue light during regular waking hours and the other half were tested during nighttime to show adverse effects of poorly timed exposure.
They suggested that as much as this kind of light exposure can produce effects on the timed release of melatonin and cortisol (3), it equally has an effect on how your brain processes emotional stimuli. Getting consistent exposure to blue light at the right time might increase the functional connectivity between the parts of your brain responsible for processing emotional feedback (the amygdala and hypothalamus).
[Related: How to get optimal sleep to recover]
Habits That Help Maintain a Healthy Rhythm
As mentioned earlier, it’s become harder and harder for humans to avoid contact with screens of any type. To power down your brain and give your mind a rest before going to sleep, a study in the Journal of Clinical Endocrinology & Metabolism recommends shutting down electrical devices 30 minutes before you’re aiming to get into bed (4).
Reducing your exposure to blue light as the sun sets is a great way to help your body fall into its natural wake-sleep cycle. Working late? Try blue light blocking glasses or adjusting your screen display to red-light.
Blast the AC at Night
We’ve all had those sleepless summer nights where the room is scorching hot and sleeping in the nude isn’t cutting it. Maintaining a cooler core body temperature at night helps recharge your brain and boosts the production of natural growth hormone(5)(6)(7)(8).
It turns out your body’s core temperature should start to decline as you start to wind down at the end of the day. It can drop from 1°C–4°C after falling into deep sleep as a result of decreased heat production from not being awake (9). The majority of studies on this topic recommend keeping your bedroom between 60 and 67 degrees Fahrenheit. Anything above 75 or below 54 degrees Fahrenheit can result in a restless, sleepless night (10).
Take an Adrenal Support Supplement
Surges of cortisol have a time and place. Involuntarily creating these spikes can cause your adrenals to fatigue overtime. Your adrenals rely on the natural release of cortisol that happens everyday upon 30 mins of waking (11). If you’ve overloaded your system from long work hours, excess stress, overtraining or under-recovering, your adrenals will shut down and won’t be able to secrete cortisol naturally which in turn will affect the production and release of melatonin in time for when you hit the sack. Try adding an adaptogenic supplement to your daily regime—such as curcurmin—to help regain that pep in your step (12).
Time Your Caffeine Intake
Depending on who you talk to, coffee is either the best thing to have ever been discovered or is seen as a direct ticket to inflammation city. As mentioned above, timing is everything when it comes to boosting energy levels and cognition.
Whether you’re looking to fall asleep soundly at night or get hyped up for a workout, consider caffeine’s effects on spiking your cortisol levels. A case in the American Journal of Clinical Pathology determined the half life of caffeine is about 5.7 hours. (8) So if your bedtime is close to 10pm, try limiting or cutting off your caffeine consumption around 4pm to let your body wind down and cortisol decrease naturally.
If you are able to take anything away from what you just read, light exposure and maintaining appropriate levels of cortisol throughout the day are both at the top of the list. Aside from helping to optimize your training, a regular circadian rhythm aids your body in functioning as a whole system. If one thing goes, the domino effect impacts the rest.
If you know your body’s internal clock hasn’t been quite right for a while, practice becoming more aware of your screen time habits, daily caffeine consumption, and sleep hygiene. Then start making small tweaks and changes everyday to slowly bring yourself back to your baseline. You’ll be surprised at how fast our bodies adjust to the environments we put them in.
- Skene DJ, Skornyakov E, Chowdhury NR, et al. Separation of circadian- and behavior-driven metabolite rhythms in humans provides a window on peripheral oscillators and metabolism. Proc Natl Acad Sci U S A. 2018;115(30):7825‐7830. doi:10.1073/pnas.1801183115
- Vandewalle G, Schwartz S, Grandjean D, et al. Spectral quality of light modulates emotional brain responses in humans. Proc Natl Acad Sci U S A. 2010;107(45):19549‐19554. doi:10.1073/pnas.1010180107
- Jung CM, Khalsa SB, Scheer FA, et al. Acute effects of bright light exposure on cortisol levels. J Biol Rhythms. 2010;25(3):208‐216. doi:10.1177/0748730410368413
- Gooley JJ, Chamberlain K, Smith KA, et al. Exposure to room light before bedtime suppresses melatonin onset and shortens melatonin duration in humans. J Clin Endocrinol Metab. 2011;96(3):E463‐E472. doi:10.1210/jc.2010-2098
- Abel T, Havekes R, Saletin JM, Walker MP. Sleep, plasticity and memory from molecules to whole-brain networks. Curr Biol. 2013;23(17):R774‐R788. doi:10.1016/j.cub.2013.07.025
- Muzet A, Ehrhart J, Candas V, Libert JP, Vogt JJ. REM sleep and ambient temperature in man. Int J Neurosci. 1983;18(1-2):117‐126. doi:10.3109/00207458308985885
- Vyazovskiy VV. Sleep, recovery, and metaregulation: explaining the benefits of sleep. Nat Sci Sleep. 2015;7:171‐184. Published 2015 Dec 17. doi:10.2147/NSS.S54036
- Takahashi Y, Kipnis DM, Daughaday WH. Growth hormone secretion during sleep. J Clin Invest. 1968;47(9):2079‐2090. doi:10.1172/JCI105893
- Saini C, Morf J, Stratmann M, Gos P, Schibler U. Simulated body temperature rhythms reveal the phase-shifting behavior and plasticity of mammalian circadian oscillators. Genes Dev. 2012;26(6):567‐580. doi:10.1101/gad.183251.111
- Onen SH, Onen F, Bailly D, Parquet P. Prévention et traitement des dyssomnies par une hygiène du sommeil [Prevention and treatment of sleep disorders through regulation] of sleeping habits]. Presse Med. 1994;23(10):485‐489.
- Eva Fries, Lucia Dettenborn, Clemens Kirschbaum⁎ Technische Universität Dresden, Faculty of Science, Department of Psychology, Chair of Biopsychology, 01062 Dresden, Germany article info abstract Article history: Received 8 August 2007 Received in revised form 11 March 2008
- Bhatia N, Jaggi AS, Singh N, Anand P, Dhawan R. Adaptogenic potential of curcumin in experimental chronic stress and chronic unpredictable stress-induced memory deficits and alterations in functional homeostasis. J Nat Med. 2011;65(3-4):532‐543. doi:10.1007/s11418-011-0535-9
- Statland BE, Demas TJ. Serum caffeine half-lives. Healthy subjects vs. patients having alcoholic hepatic disease. Am J Clin Pathol. 1980;73(3):390‐393. doi:10.1093/ajcp/73.3.390
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