Sleep Cutoff Line

Body & Recovery

Claim
Setting a hard cutoff time for caffeine and screens in the evening is one of the simplest ways to improve sleep quality and next-day energy, because it removes two of the biggest sources of late stimulation.

Why it matters
• Caffeine has a long half-life, so afternoon and evening use can still affect sleep hours later.
• Bright screens close to bed keep the brain in “daytime” mode and delay natural sleepiness.
• Better sleep quality improves focus, mood, training performance, and decision making the next day.

Action

  1. Pick a daily cutoff time for caffeine and energy drinks, at least 6 hours before you plan to sleep.

  2. Set a screen “dim and dock” time about 60–90 minutes before bed, where devices go on low brightness and off your bed.

  3. Track how you feel and perform for the next 7–10 days, then adjust your cutoff times if needed.

Source
Caffeine and sleep disruption – Gardiner et al., 2023, Sleep Medicine Reviews (systematic review and meta-analysis on caffeine’s effect on night-time sleep). PubMed

Timing of caffeine before bed – Drake et al., 2013, Journal of Clinical Sleep Medicine (400 mg caffeine taken 0, 3, or 6 hours before bedtime). PubMed · Free full text

Evening light-emitting screens and circadian delay – Chang et al., 2015, PNAS (light-emitting eReaders before bed); Chinoy et al., 2018, Physiological Reports (tablet use in the evening). PubMed · Publisher

Sleep restriction and next-day performance – Van Dongen et al., 2003, Sleep (dose–response effects of chronic sleep restriction on neurobehavioral performance). PubMed