Achieving sleep isn't just about feeling tired; it's a physiological shift. A key biological marker for entering a state of unconsciousness is having a heart rate of approximately 60 beats per minute or lower. This makes heart rate a critical and measurable target for pre-sleep routines.

Waking up between 1-3 AM is a natural process as your body reheats to avoid hypothermia. To fall back asleep, avoid activities that raise your heart rate (like getting up), which should stay below 60 BPM. Use 4-7-8 breathing to relax instead.

Insomnia is often maintained by 'conditioned arousal,' where your brain learns to associate your bed with being awake (from working, watching TV, or worrying in it). To break this, if you're awake for 20 minutes, get out of bed until you're sleepy again to re-teach your brain that bed is only for sleep.

Forget complex sleep metrics; the single highest-value biomarker to track for sleep quality is your resting heart rate just before bed. Actions that lower it (e.g., early final meal, no screens) are beneficial, while those that raise it are detrimental. It provides a simple, actionable daily target.

Eating is a sympathetic (arousing) activity. Stopping food intake three hours before sleep is critical for allowing the parasympathetic nervous system to dominate. This enables a nightly cardiovascular "reset" where blood pressure and heart rate dip, significantly lowering cardiovascular risk.

Bryan Johnson suggests focusing on a single metric: pre-sleep resting heart rate. Lowering it through specific habits (like eating 4 hours before bed) improves sleep quality, which in turn boosts your prefrontal cortex, enhancing willpower and alleviating mental health issues.

It's biologically normal for every human to wake between 1-3 AM. This is when your core body temperature hits its lowest point, and the brief arousal is a survival mechanism to prevent hypothermia. The issue isn't waking up, but rather failing to immediately fall back asleep.

A prerequisite for falling asleep is shutting down proprioception—your awareness of body position. Performing slow, deliberate eye movements (side-to-side, circles) can trick your vestibular system into this state, helping a racing mind fall asleep.

The habit of checking your phone immediately upon waking conditions your brain to anticipate a morning anxiety spike from incoming messages and agendas. This creates a state of 'anticipatory anxiety' before you even fall asleep, leading to shallower, less restorative rest.