The Sereno Journal

Stress science, breathing techniques, and the story behind the score. Written by the people building Sereno.

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What Your Heart Rate Variability Actually Tells You About Stress

What Your Heart Rate Variability Actually Tells You About Stress

HRV measures the variation between heartbeats. Research suggests it is one of the most reliable real-time indicators of how your nervous system handles stress.

Sereno Team · · 16 min read
The Science of Stress: What Your Body Is Actually Doing
Stress Science

The Science of Stress: What Your Body Is Actually Doing

Stress is not just a feeling. It is a measurable cascade involving hormones, heart rate, and nervous system activation. Here is what happens.

Sereno Team · · 16 min read
5 Breathing Techniques That Actually Lower Your Stress Response
Breathing

5 Breathing Techniques That Actually Lower Your Stress Response

Controlled breathing is the fastest way to shift your nervous system from fight-or-flight to rest-and-digest. These 5 techniques are backed by research.

Sereno Team · · 17 min read
How Sleep and Stress Feed Each Other, and How to Break the Cycle
Sleep

How Sleep and Stress Feed Each Other, and How to Break the Cycle

Poor sleep raises stress. High stress ruins sleep. Research shows this bidirectional loop and evidence-based ways to interrupt it.

Sereno Team · · 17 min read
A Practical Guide to Tracking Stress with Your Wearable
Wearables

A Practical Guide to Tracking Stress with Your Wearable

Your Apple Watch, Oura Ring, or already collects the data. Here is how to turn wearable health metrics into actionable stress insights.

Sereno Team · · 18 min read