Caffeine Half-Life & Sleep Window Calculator

← すべてのツール / Caffeine Half-Life & Sleep Window Calculator

Calculate how long caffeine from coffee or pre-workouts stays active in your system before sleep.

Caffeine Dose Intake (mg)

Hours Elapsed Before Sleep

Caffeine Timing and Muscle Growth

Caffeine has a half-life of roughly **5 hours** in healthy adults. Drinking strong pre-workout formulas or espresso too close to bedtime blocks adenosine receptors, preventing deep slow-wave sleep. Since muscle repair and growth hormone secretion peak during deep sleep, poor sleep hygiene directly halts gym gains.

よくある質問

Ideally, cut off all caffeine intake at least 8 to 10 hours before your planned bedtime.

No, liver CYP1A2 enzymes govern caffeine metabolism. Fast metabolizers clear it quickly, while slow metabolizers experience effects much longer.