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The effect of caffeine on subsequent sleep: a systematic review and meta-analysis
Gardiner C, Weakley J, Burke LM, et al. · Sleep Medicine Reviews 69:101764 · 2023
Key finding
Caffeine reduced total sleep by ~45 min and efficiency by 7%. To avoid effects, a coffee (~107 mg) should be ~8.8 h before bed; a pre-workout dose (~217 mg) ~13 h.
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