CortexLit

CortexLit tool · Caffeine · Runs offline · No account

Pre-Workout Caffeine Planner

Set a pre-training dose and a latest time that survives your bedtime buffer, and print the rule you will actually follow.

← Back to the article · See the evidence

This tool gives general information based on the research summarised in Caffeine Before Exercise: What the Evidence Supports. It is not a medical device, does not diagnose, and does not replace advice from your clinician.

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Free (this page)
  • dose and take-time from your schedule
  • cut-off check against your bedtime buffer
  • text export and print
  • all citations and cautions


Plus (optional, one-time)
  • calendar (.ics) session reminders
  • unlimited share images
  • share card without the 'Made with CortexLit' footer


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Free tier: 1 share image per result.






Commercial disclosure: optional paid Plus tier; all evidence, cautions and the main result are free. No affiliate links, no sponsors.







What this is based on


Every output names at least one verified PubMed source. Identifiers were verified on 2026-10-11 in an earlier batch and carried over into this build; they were not re-queried here, and no retraction database was checked. Verification was at abstract level.


Drake 2013
Drake C, Roehrs T, Shambroom J, Roth T. Caffeine effects on sleep taken 0, 3, or 6 hours before going to bed. J Clin Sleep Med. 2013;9(11):1195-1200.
PMID 24235903 · randomized controlled trial · weight 0.8 · abstract level
Wikoff 2017
Wikoff D, Welsh BT, Henderson R, et al. Systematic review of the potential adverse effects of caffeine consumption in healthy adults, pregnant women, adolescents, and children. Food Chem Toxicol. 2017;109(Pt 1):585-648. doi:10.1016/j.fct.2017.04.002. PMID: 28438661.
PMID 28438661 · systematic review · weight 1.0 · abstract level
Gardiner 2023
Gardiner C, Weakley J, Burke LM, et al. The effect of caffeine on subsequent sleep: A systematic review and meta-analysis. Sleep Med Rev. 2023;69:101764.
PMID 36870101 · systematic review meta analysis · weight 1.0 · abstract level


Limits: This schedules a time; it does not predict your sleep or your training. Individual caffeine clearance varies widely, so six hours is a starting point from the trial, not a personal guarantee.







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