Why good sleep habits are important for success on test day

by Erin Ohsie-Frauenhofer, Arborbridge
April 14, 2021

You may have heard it's not a good idea to pull an all-nighter before an exam. But why does getting a good night's sleep affect your performance on test day, and is there a certain amount of sleep that really makes a difference?

Why is sleep important?

Sleep has numerous effects on students' retention and cognitive function. Longer sleep duration, better sleep quality, and greater sleep consistency are associated with better academic performance. On the flip side, a lack of sleep can reduce your capacities for focusing and recalling information, slow down your reaction times, and affect your decision-making abilities.

All of these factors play important roles in academic settings. When you're taking any kind of standardized test—like the SAT, ACT, ISEE, SSAT, or TOEFL, to name a few—you need to be able to read and think quickly while making efficient decisions about prioritizing questions and pacing yourself. Furthermore, good sleep habits are critical when it comes to learning content and remembering what you've learned, which can affect your day-to-day performance in school as well as your ability to recall information on tests such as AP exams.

How much sleep do students need?

The National Sleep Foundation recommends that teenagers get 8-10 hours of sleep per night. Every little bit helps, but getting adequate sleep for just one night isn't enough to make a significant difference. That means if you were hoping to suddenly catch up on weeks of sleep deprivation the night before test day, you'll want to adjust your plans and think bigger picture.

Students should aim to stick to a consistent sleep routine for at least 5 days leading up to the day of the exam. And, given all the benefits of sleep, making long-term improvements to your sleep habits can be even better for you.

What are good sleep habits, and where do I start?

It can be hard to change your sleep habits—even if you know how important they are. Start small, and don't pressure yourself to do everything perfectly right away. (Overthinking it can have the opposite effect!)

Here are some tips to keep in mind:

Stick to a consistent sleep schedule. Try to go to bed and wake up around the same time every day, aiming for 8-10 hours of sleep each night. It's important not to stay up too late: two MIT professors found that people seem to have a cutoff bedtime, which can vary from one person to another. Students who go to bed after their individual threshold time tend to perform worse on tests, no matter how much total sleep they end up getting.

Figure out an evening routine that works for you. A consistent routine is one way to help train your body to fall asleep around the same time each night.

It's a good idea to limit caffeine, bright lights, and strenuous exercise a couple of hours before you go to bed.

Organizing your thoughts can go a long way toward helping you fall asleep—and stay asleep. Spend just a few minutes reflecting on the accomplishments you're proud of and updating your task list for the next day. If you're feeling especially anxious or worried, writing down your thoughts can help ease your stress levels.

For some people, a bedtime hygiene ritual can be a nice way to relax. Consider playing some calming music in the background as you wash up and change into comfortable clothing.

Controlled breathing exercises and stretching can help you lower your heart rate and clear your head before you get into bed.

Reward yourself. Celebrating your successes can help you stay motivated to stick with your new habits. When a Baylor University professor bribed his students to sleep at least eight hours a night for one week, the students who completed the challenge scored nearly five points higher on their exams (not counting the extra credit they were bribed with). So, come up with a fun way to reward yourself for sticking to your sleep schedule for a certain number of days: treating yourself to your favorite meal, buying something that relates to a favorite hobby, planning a fun activity with friends, etc.

Not only is sleeping a more pleasant and fulfilling way to prepare for test day than a last-minute cram session, but it's healthier for you in the long run. Though shifting your sleep habits may take some time, it's time well spent.