"Catching up on sleep on the weekend is fine"—that habit was creating the heaviness of Monday
On the weekend, I was finally able to sleep in for the first time in a while.
Saturday morning, I wake up before the kids wake me. "I'll sleep in a little longer today." I wake up two hours later than usual. "With this, I'll be able to move energetically next week."
And yet, for some reason, Monday morning is the heaviest.
"I slept so much, so why do I feel so exhausted?"
Do you know the answer to that?
Actually, "catching up on sleep" on the weekend may be what is creating the heaviness of Monday. A accumulation of good intentions was creating the melancholy of every Monday—today, I will tell you about the mechanism behind this and a simple solution.
◎ Catching up on sleep does not count as "repaying a debt"
"If I sleep in on the weekend, I can make up for the lack of sleep during the week"—many people believe this. However, brain science denies it.
Dr. Walker (Walker, 2017) compares sleep debt to a "debt that cannot be repaid." Cognitive function that has declined due to chronic sleep deprivation does not fully recover just by sleeping long on the weekend. Even if you feel like your sleepiness has temporarily gone away, your brain's performance has not returned to its original level.
The further problem is that sleeping long on the weekend itself creates another "loss."
◎ "Social Jetlag"—the true identity of Monday's heaviness
Do you know the term "social jetlag"?
It is a concept proposed by Roenneberg et al. (2012) of the University of Munich, referring to "social jet lag" caused by the gap between weekday and weekend sleep schedules.
When you travel abroad, your body feels heavy due to jet lag, right? The same thing happens every weekend.
You wake up at 7:00 on weekdays, but sleep until 9:00 on the weekend. A gap of just two hours. But for your brain and body, this is the same as taking a "two-hour time difference trip" every weekend.
On Monday morning, your body is still in "Saturday time." It takes two to three days for your brain to return to the weekday rhythm. That's why you finally start feeling good around Wednesday, then the weekend comes again, and it gets disrupted again—this is the cycle.
The reason "Monday is the hardest" is not because you lack motivation or because you hate your job. It is because you are causing jet lag in your brain every weekend.
◎ 3 reasons why the more you catch up on sleep, the heavier Monday becomes
Let's delve a little deeper into the mechanism.
The first is the disruption of the serotonin rhythm. Serotonin is a neurotransmitter that serves as the foundation for stability and motivation, and its secretion is promoted by waking up at the same time every morning and being exposed to light. When you wake up late on the weekend, the timing of this serotonin secretion shifts. Because you start Monday morning in a state of serotonin deficiency, your mood doesn't lift.
The second is the abnormality of cortisol. When your internal clock is disrupted, the timing of the morning "cortisol awakening response"—the secretion of the hormone that switches your body into activity mode—also shifts. On Monday morning, your body decides that "it's not time to wake up yet," making it unusually difficult to get out of bed.
The third is the confusion of the internal clock itself. The internal clock stabilizes by "ticking at the same rhythm every day." By shifting it by two hours on the weekend, your precise 24-hour internal clock goes haywire. This is the root of all the disruption.
◎ Just "fixing your wake-up time" will change Monday
So, what should you do?
It's simple. Keep your wake-up time the same on both holidays and weekdays.
That's all.
I understand the feeling of "but I want to rest on the weekend." There is an important shift in perspective here. "Waking up late" is not rest; by causing a shift in your internal clock, it actually increases your fatigue for the following week.True rest is getting high-quality sleep without disrupting your internal clock.
While keeping your wake-up time fixed, go to bed a little earlier. This is the simplest way to make the following Monday easier.
The goal comes first! The method comes later!—Place the goal of "being able to start moving clearly on Monday morning" first. To achieve that, you will be able to choose the method of waking up at the same time on weekend mornings as well.
Time flows from the future. The lightness of next Monday is determined by the wake-up time this weekend.
◎ "When I stopped sleeping in on the weekend, Monday became a different thing"
Let me tell you the story of a mother in her 30s.
There was someone who told me, "Every Monday is depressing, and I feel exhausted for the first half of the week." She said her pattern was always staying up late after her children went to sleep on the weekend and sleeping until around 9:00 AM the next morning.
What I had her try was just waking up at 7:00 AM on the weekend, nothing more. She said, "The first week felt like it wasn't enough." But two weeks later, she said, "This Monday, I was able to wake up normally for the first time."
Just by regulating your internal clock, Monday changes this much. Her words still leave an impression on me.
◎ Summary
I will summarize what I have shared today into three points.
・Sleeping in on the weekend does not pay off sleep debt. Instead, it disrupts your internal clock and makes Monday feel heavier.
・The gap between weekday and weekend wake-up times causes "social jetlag"—it is caused by experiencing jetlag every weekend.
・The solution is simple. Wake up at the same time on weekends as you do on weekdays. That alone will change your Monday.
Everyone is the manager of their own "body." If you were throwing off the precision machinery that is your internal clock every weekend—fixing that first is the most rational management decision.
Sleep is a skill and a tool. If you want to change next Monday, try waking up at your usual time this coming weekend morning.
—Have a pleasant day today as well.
■ References
・Roenneberg, T., et al. (2012). Social jetlag and obesity. Current Biology, 22(10), 939-943.
・Wittmann, M., et al. (2006). Social jetlag: Misalignment of biological and social time. Chronobiology International, 23(1-2), 497-509.
・Walker, M. (2017). Why We Sleep: Unlocking the Power of Sleep and Dreams. Scribner.