Have you ever had an assignment or project to get done in a few days, and you decided to stay up late to get more done? Then you have fallen prey to this mistake.
Borrowing Time From Tomorrow
Staying up an extra three hours at night to continue working on a project has a few outcomes.
- Your ‘work completed’ is increased for the day because you spent more time on it
- You go to bed three hours later and either
- wake up three hours later;
- get three hours less sleep; or
- some combination of (a) and (b)
- Your ‘work completed’ in the future is decreased either because
- you had three hours less time than usual in your day, so you spent less time working;
- you functioned at a decreased capacity than usual because you were sleep deprived; or
- some combination of (a) and (b)
The question is: does the increase in productivity at the beginning outweigh the decrease in productivity afterwards?
In my experience? No.
Your Body Clock
Your body gets used to the times that it goes to sleep and wakes up at. Do you remember the days after the last daylight-savings change? The clock went forward an hour and you suddenly started struggling to get up at your usual alarm time. It probably took close to a week before your body had adjusted to the new sleep and wake times.
When you choose to stay up three hours later than you normally would, your body has already assumed it’s time to sleep and it starts to slow you down. Unless you fill yourself full of caffeine or sugar (which has its own downsides) to counteract these effects, your productivity will decrease.
So those three hours you’ve taken from tomorrow are going to be less productive than if you went to bed at normal time and continued the next day.
Additionally, if you normally get up at, say, 7am, and you want to get your usual amount of sleep, trying to get up at 10am isn’t going to work — your body clock will wake you up earlier.
Not getting your minimum amount of sleep each night results in you accumulating sleep debt.
For example, you have monitored your sleep duration, sleep quality, and energy levels for enough weeks that you estimate your minimum sleep requirement to be eight hours. If you only get seven hours each weeknight, you will probably find yourself feeling more and more sluggish until you’re at work or school on a Friday and just wishing the day will end because you don’t have the mental capacity to handle serious work.
Because you’re essentially borrowing one hour each night from your future self, you are five hours in debt by the end of the week. Instead of getting up at your usual 7am, you probably stay asleep until 10am to 12pm (depending on how far your body clock lets you go and exhausted you are). If you woke up at 10am, that means there are two hours of debt left, which you might make up for the next day.
Each day you are in debt to sleep, your concentration, cognitive ability, and productivity take a hit. You are better off in the long run if you have regular sleeping hours and consistent energy levels.
The Problem With Relying on Sleep Debt and Catch-Up Sleeps
Regularly going from low sleep quantity during the week to high sleep quantity on the weekend might have you thinking that your sleep debt’s all clear. It might be. But your body clock is getting pushed around.
During the week your body gets used to getting up at 7am, then loses that familiarity as you binge sleep on the weekend. No wonder Monday is a struggle for most people — their body clock is expecting another 9am-ish wake-up time but you’re making it get up at 7am.
When It’s Worth Working Late
The only scenario where it might be worth trading sleep now for sleep later is when productivity now is more important than productivity later.
For example, if you have problems with procrastination, you might leave your assignment/project until the night before it’s due. Getting the work done tonight would be much more valuable to you than getting it done after the due date.
There is still a price to pay in productivity in the following days until you can catch up on sleep and regular waking hours. However, that price might be worth paying in these circumstances.
Staying up late is a short-term boost in productivity with downsides that could be a short-term solution to some of your problems. But for long-term productivity, get consistent sleep and have consistent wakeup times.