Peer-reviewed study
Caffeine timing has a real sleep cost
The effect of caffeine on subsequent sleep: A systematic review and meta-analysis
Source details
PubMed-linked study details.
- Authors
- Gardiner et al.
- Journal
- Sleep Medicine Reviews. 2023.
- Identifiers
- PMID 36870101 · DOI 10.1016/j.smrv.2023.101764
Claim guardrail
What this page should prevent.
Do not claim one universal cutoff for everyone. Use the evidence to justify a personal timing experiment.
Geebs coaching takeaway
The study only matters if it changes a behavior.
A regular person does not need a complicated sleep stack before testing caffeine timing, dose, and pre-workout habits.
Content angles
Safe ways to translate it.
Your afternoon caffeine can become tonight's recovery problem
Pre-workout has a bedtime receipt
Energy timing is recovery programming
Exact answer pages
Questions that cite this source.
Caffeine and sleep answer
Does caffeine affect sleep even if you fall asleep?
Yes, it can. Falling asleep is not the only sleep outcome. Caffeine timing can affect sleep duration, quality, and recovery, which is why late pre-workout or afternoon coffee deserves a simple experiment.
Sleep performance answer
Does sleep loss hurt workout performance?
Sleep loss can make performance worse and make the same session feel harder. That does not mean the workout is useless. It means sleep should inform the day's volume, intensity, and expectations.
Caffeine and recovery answer
Can caffeine save a bad night of sleep?
Caffeine can help some people perform after short sleep, but it is not recovery. It is a temporary performance tool, and the timing can backfire if it pushes the next night's sleep later.
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