Adolescents consistently seem to feel tired, even after an eight-hour night’s rest. After such adequate amounts of sleep, why do we still feel tired?
The Phone
Though you might think the time you spend doom-scrolling before bed is winding your body down, it’s actually doing the opposite. Doom-scrolling engages your brain and emits blue light, both of which reduce melatonin by 50% and delay REM. Even after being on your phone, your mind stays active long after you have put your phone away.
For optimal sleep, it is recommended to stay off screens for 30-60 minutes before bedtime.
Day-to-day activities (sitting)
Being a high school student, sitting takes up most of the day. You wake up, sit for breakfast, then sit in a car to get to school, sit in class for around six hours a day, and then go home to sit and do homework and eat dinner. While it may seem like sitting down for long periods of time would make you tired, in reality, it’s the opposite.
When sitting for a long time, the body works hard to pump blood through the brain and muscles. By the time you go to bed, the body is exhausted from the lack of movement, leading to a heavy and slow feeling when you wake up.
During the day, stand up and walk around between classes, exercise before sitting for long periods of time for homework or other sedentary activities, or aim for about 7,000 steps a day.
Stress and anxiety
Stress during the day activates the Hypothalamic-Pituitary-Adrenal (HPA) axis in the brain, which releases cortisol, the stress hormone. High levels of cortisol during the day and evening are linked to sleep latency and less slow-wave sleep, crucial to waking up feeling revitalized.
Stress also keeps the brain in a state of hyper-arousal. Even if you don’t fully wake up, the brain experiences micro-arousals that keep you in light sleep instead of slow wave. The prefrontal cortex, which handles decision-making, becomes exhausted after a long day of high-stress decision-making. This prolonged mental fatigue often carries into the next day because the brain takes more than one sleep cycle to fully recover.
Dehydration
The human brain is about 75% water. If you are even slightly dehydrated, your blood volume drops, and your heart has to work much harder to pump enough blood to your muscles and brain. This results in a constant feeling of exhaustion, regardless of the amount of sleep.
Throughout the day, keep a water bottle with you to ensure hydration. Having one with you constantly will prompt drinking it, consequently improving sleep.
