¶ Sleep & Circadian

¶ Summary

Sleep is one of the highest leverage “inputs” for nearly every other outcome (metabolic health, mood, recovery, cognition). The best sleep biohacks are usually environment and timing — not stacks.

¶ What to Track (Start Simple)

• Primary: wake time consistency, total sleep time, subjective sleep quality.
• Secondary: sleep latency, night awakenings, next-day energy.
• Optional: resting heart rate trend, HRV trend (if you use a wearable).

¶ Common Interventions

• Morning light exposure (timing matters more than intensity chasing).
• Regular sleep schedule (wake time anchor).
• Temperature + light environment (cool/dark/quiet).
• Caffeine timing (stable dose; earlier cutoff).
• Stress downshift: Stress Management

¶ Testing & Biomarkers (Optional)

• If persistent issues: discuss screening for sleep apnea, iron status (ferritin), thyroid context, etc. with a clinician.

¶ First Experiment (ABAB)

• A (7 days): current routine, track sleep timing + latency.
• B (7 days): add morning outdoor light + fixed wake time.
• A (7 days): remove light timing change (keep tracking).
• B (7 days): reintroduce.

¶ See Also

• Sleep
• Biohacking: Baseline Setup
• N‑of‑1 Experiments