Mental Health · 4 min
Regulating the nervous system
Chronic stress is not, on its own, the problem. The problem is the loss of the ability to come down from it. Every system we care about — cardiovascular, immune, metabolic, cognitive — depends on the autonomic nervous system being able to oscillate, not stay stuck on alert.
What HRV is telling you
Heart rate variability — the small beat-to-beat variation in your pulse — is a window onto vagal tone. Higher HRV indicates a nervous system that can flex between sympathetic and parasympathetic activity. Persistently low HRV predicts poor recovery, higher cardiovascular risk, and worse mood regulation.
Slow breathing is the most direct lever
Breathing at around 5–6 breaths per minute, with a longer exhale than inhale, reliably increases vagal tone within minutes. A meta-analysis of slow-breathing interventions found consistent improvements in HRV, blood pressure, and self-reported anxiety. The effect is mechanical: longer exhales activate the baroreflex, which directly engages the parasympathetic branch.
Build it into the day, not just into a crisis
Five minutes of slow breathing in the morning, a brief downshift before meals, and a longer practice (yoga, meditation, walking, time in nature) several times a week trains the system more than any single technique used reactively.
What to do this week
- Twice a day, breathe at 6 breaths per minute for 5 minutes — inhale 4 seconds, exhale 6.
- Get outside, ideally somewhere green, for 20 minutes daily.
- Track HRV over 2–4 weeks (most wearables do this) and watch the trend, not the day.
- Reduce alcohol — it dramatically suppresses HRV for 24–48 hours after drinking.