AMA #18: Cold Therapy Advice, Skin Health Tips, Motivation, Learning Strategies & More

Excessive sun exposure unequivocally accelerates skin aging and thinning. Huberman recommends physical barriers (hats, clothing) and, when needed, mineral sunscreens (zinc oxide or titanium dioxide up to ~25%) as first-line protection. For improving skin elasticity and plumpness, moderate evidence supports 15–30 g/day collagen (often with vitamin C), 10–15 minutes of red/near-infrared light several days per week, prescription retinoids under dermatologist supervision, and laser resurfacing by qualified derm-oncologists—plus basics like low-inflammatory diet, essential fatty acids, and regular moisturizing.

The effective cold-therapy stimulus is subjective: water should be cold enough that you want to get out but can safely stay in 1–3 minutes (or ~30 seconds if you’re highly resistant). For most people this is ~45–50°F (7–10°C), starting warmer (55–60°F) if new, and only going into the low 40s/high 30s with supervision and caution. Never hyperventilate or do heavy breathwork before getting into cold water due to blackout and drowning risk, and treat cold as a powerful stimulus where the minimum effective dose is best.

Instead of publicly announcing goals, Huberman suggests writing them down, creating a signed ‘contract with self’, and checking off each completed session (e.g., 10–60 minutes of writing or a 30-minute workout). The signature and check mark become the reward, reinforcing the principle that effort is the reward (growth mindset). External praise and accountability can help, but over-reliance on others’ validation weakens intrinsic motivation; he recommends becoming your own ‘committee’ while minimizing phone distractions and, if necessary, adding meaningful stakes (e.g., financial penalties) to enforce focus blocks.

REM sleep is critical for emotional processing and consolidating learning, especially the night after training. You can increase REM by adding 10–30 minutes of morning sleep when possible, doing early-day exercise and/or deliberate cold exposure to spike adrenaline (which biases more REM that night), and using non-sleep deep rest (NSDR) the next morning when REM was short. The brain naturally exhibits REM rebound the following night after REM-restricted sleep, and there is currently no robust, REM-specific pharmacology; alcohol and late caffeine should be avoided if REM quantity and quality are priorities.

For schools, Huberman highlights three high-impact, low-cost practices: (1) short daily meditation or NSDR (3–5+ minutes) before learning, leveraging findings from Wendy Suzuki’s lab that ~13 minutes per day can enhance focus, working memory, and stress regulation; (2) frequent 10–20 second ‘micro-gaps’ during lectures, which promote rapid replay of newly learned material in hippocampus and cortex, increasing repetitions passively; and (3) daily physical activity—especially cardio—before learning bouts to elevate catecholamines (dopamine, norepinephrine, epinephrine), which facilitate encoding.