Research

Mixed

Consistent sleep duration, higher sleep quality, and longer total sleep duration over the month leading up to an assessment are associated with better academic performance in college students.

To improve your grades, focus on getting enough sleep, sleeping well, and keeping a consistent schedule throughout the week leading up to your exams, rather than just trying to cram sleep the night before. Consistency matters more than a single good night's rest right before a test.

GoodSupportsHIGH confidence
Overall, better quality, longer duration, and greater consistency of sleep correlated with better grades. ... sleep duration and quality for the month and the week before a test correlated with better grades.
Kana Okano et al. · npj Science of Learning · 2019

Why this rating

Objective wearable data collected over a full semester in a real-world setting, though observational and not experimental.

Source

Sleep quality, duration, and consistency are associated with better academic performance in college students

Kana Okano et al. · npj Science of Learning · 2019

DOI 10.1038/s41539-019-0055-z

cohort · n=88Cited 317×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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