#4 - Sleep - The Big Three
Performance, mental health (focus, accuracy, memory), metabolic health (burning fats vs carbs), immune function, and cardiovascular health are all influenced by sleep. Nobody needs to be convinced that more sleep will, undoubtedly, be better for them. Yet, we find it increasingly difficult to feel tired when we want to go to bed. Three major components influence three key hormones that help to regulate our propensity to fall asleep.
The first component is the world’s most used drug, caffeine, the key ingredient in coffees, teas and energy drinks. Upon waking, our brain starts accumulating a compound called adenosine in the brain. When adenosine binds to the adenosine receptors in the brain, a reduction in brain cell activity occurs, which causes the onset of fatigue and drowsiness. When we ingest coffee, the caffeine binds to the adenosine receptors, blocking the onset of fatigue. Caffeine delays the onset of fatigue.
The issue comes into play when the caffeine is still in our brain when we want to get ready for bed. The half-life of caffeine, the amount of time it takes the body to metabolize (reduce) the amount of caffeine by half, is 6 hours. A venti sized Starbucks coffee has approximately 400 mg of caffeine in it, equivalent to 5-6 cups of typical home-brewed coffee. If you finish your 400 mg coffee at 10:00 AM, then you will have 200 mg of caffeine in your system at 4:00 PM and 100 mg of caffeine in your system by 10:00 PM.
The strategy here would be to become aware of your caffeine intake, the time of intake and whether or not you feel “sleepy” at bedtime. The first component is your body’s propensity to feel tired.
The second component is on the other side of the spectrum from feeling fatigued, which is feeling alert. Our bodies have a natural rhythmic, alerting system called our circadian rhythm. Our circadian rhythm is responsible for keeping us alert or feeling awake throughout the day. The circadian rhythm is stimulated by both artificial and natural light. This is a primary reason why we feel more alert during the day. The issue here comes into play when our alerting system is still heightened when we want to go to bed. We referenced how our internal clock is stimulated by light. Our brain starts producing a hormone melatonin which quiets our alerting system; however, our body does not start to produce melatonin if the body is still being stimulated by light. At night, blue light or LED light emits short wavelength energy (light) that continues to stimulate the brain, preventing melatonin production. This may be experienced as lying in bed and still feeling awake or alert.
There are a number of strategies to reduce our light exposure in the evening and night. Some of the most common include setting the night shift app on your phone, downloading blue light blocking apps for your laptop or computer, switching to soft or dim lighting in the evening, or swapping out night time routine activities such as watching TV or playing games to reading, meditation or yoga.
Our propensity to feel fatigue corresponds with the quieting of our alerting system to help us go to sleep. Keeping these two in balance are two primary components of getting to sleep. Even if we have these two in sync, the third component can supersede the effects of accumulated fatigue and a quiet alerting signal.
Acute stress, a stress response, or a “fight or flight” response can stimulate our body through the release of adrenaline. Adrenaline prepares our body for activity by increasing heart rate, shunting sugar into the bloodstream and increasing blood pressure. This, of course, is the opposite state we want to prepare for sleep. The body can take up to 20 minutes to recover from an acute stress response. This could be the email, text or argument that occurred close to bedtime; It could be the restless thoughts when you lay down to bed; It can be multiple stress responses that continue to happen that keep you from feeling “tired” to go to bed.
The strategy here would be to incorporate a stress reduction activity before and/ or remove your stressors as part of your nighttime routine. Some common stress relief strategies include: reading, stretching, listening to music, meditation, decaffeinated tea, drawing, journaling and etc.
Now you have insight of three components of sleep - fatigue, alertness, and stress - as well as three key hormones - adenosine, melatonin and adrenaline. The next step would be to take action. Select an area(s) to try and change!
Cheers,
Steve
Sources:
https://www.caffeineinformer.com/caffeine-content/starbucks-grande-coffee
https://science.howstuffworks.com/caffeine4.htm
https://www.precisionnutrition.com/hacking-sleep
https://www.precisionnutrition.com/wp-content/uploads/2018/08/power-of-sleep-infographic-tablet.pdf
