Where this was said
Late-Day Training & Pre-Workout, Cortisol; Tools: Alpha-GPC, Garlic & TMAO, Hot Shower, Physiological Sigh, Post-Workout Food
At 6:55 · chapter starts 1:42
Anthony Richards opens the Q&A asking how to get a productive strength workout late at night without destroying sleep an hour and a half later. Huberman frames the problem clearly: late workouts appropriately spike cortisol, and the challenge is energizing enough to train hard while setting up a clean wind-down. His solution is Alpha-GPC (600–900mg), unique among alertness tools because it works via acetylcholine — not catecholamines — and either spares or modestly boosts REM sleep. [1] — Andrew Huberman "Alpha-GPC is the only over-the-counter supplement that boosts alertness and workout intensity while either leaving REM sleep intact or mode…" 05:10 The caveat is significant: Alpha-GPC potently raises TMAO, a cardiovascular risk marker, so Huberman recommends taking 600mg of garlic (which contains allicin) every time to inhibit TMAO production in the gut. He also advises limiting Alpha-GPC to 2–3 times per week to preserve its effectiveness and cap exposure. The second half of the answer covers zero-cost wind-down tools: a hot shower (paradoxically drives core body temperature down via hypothalamic neurons) and deliberate long-exhale physiological sighs to activate descending vagal pathways and slow heart rate. Huberman closes with practical nutrition advice — a small serving of casein protein or oatmeal after a hard late workout can prevent hunger-based 3 AM awakenings without meaningfully disrupting growth hormone release.
Alpha-GPC is the only over-the-counter supplement that boosts alertness and workout intensity while either leaving REM sleep intact or modestly increasing it. Unlike caffeine or classic stimulants that drive sympathetic arousal and wreck sleep, Alpha-GPC works via the acetylcholine pathway — and that distinction matters enormously if you train late.
Alpha-GPC is the only supplement Andrew Huberman knows of that can increase alertness and workout intensity while also modestly increasing REM sleep rather than harming it.
Alpha-GPC can raise TMAO levels, which carries cardiovascular risk; pairing it with 600mg of garlic (allicin) can help inhibit TMAO production.
Alpha-GPC potently raises TMAO — a compound linked to cardiovascular risk including stroke. Taking 600mg of garlic (which contains allicin) at the same time inhibits TMAO production in the gut. Huberman recommends pairing them every time and capping Alpha-GPC use at 2–3 times per week.
Taking a hot shower after a late workout warms the skin surface, triggering neurons in the hypothalamus to drive core body temperature down — a prerequisite for falling asleep.
A hot shower after late-night training paradoxically drives core body temperature down — exactly what the brain needs to initiate sleep. Pair it with deliberate long-exhale breathing (the physiological sigh) to activate the descending vagal pathway, slow heart rate, and lower sympathetic arousal within minutes.
