Science
Science evidence about HRV
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HRV: A Window into Your Body’s Balance
Heart Rate Variability (HRV) measures the tiny, natural fluctuations in the time intervals between consecutive heartbeats. Unlike a steady metronome, a healthy heart speeds up slightly when you inhale and slows down when you exhale.
These variations arise from the dynamic interplay between the sympathetic nervous system (SNS, “fight-or-flight”) and the parasympathetic nervous system (PNS, “rest-and-digest”).
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HRV Links to Sleep and Stress
HRV reflects sleep quality and stress resilience. Adequate sleep boosts parasympathetic (PNS) activity, enhancing HRV during deep sleep as the body repairs itself. Poor sleep lowers HRV, increasing fatigue. Good sleep quality is typically associated with higher HRV metrics, such as RMSSD and SDNN.
Higher HRV signals stress resilience; lower HRV indicates sympathetic (SNS) dominance—triggering adrenaline and reducing variability. Chronic SNS overactivity from prolonged stress depletes HRV, raising risks of burnout and cardiovascular strain.
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HRV and the Vagus Nerve
The vagus nerve (parasympathetic) controls HRV: strong vagal tone increases heart variability during relaxation. Deep breathing and meditation enhance vagal tone, raising HRV; chronic stress or inflammation lowers it by weakening vagal function.
This explains why vagus-focused practices (e.g., yoga, cold exposure, breathwork) improve HRV and alleviate stress or insomnia. HRV acts as a “vagal health meter,” reflecting your nervous system’s adaptability to stress and recovery capacity.
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ZenoWell Chief Scientist
Meet the Health Professionals
Cognitive neuroscientist with over a decade of research in neuroimaging, neuromodulation, sleep, and emotional regulation. She brings academic rigor and data-driven insight to ZenoWell, ensuring every protocol is grounded in science and optimized for real-world impact.
Dr. Jane earned her Ph.D. from The Chinese University of Hong Kong, with a unique interdisciplinary background spanning veterinary medicine, psychology, and cognitive neuroscience. Her deep passion for both neuroscience and animals has shaped her holistic approach to wellness and healing.
At the heart of Jane's philosophy is the belief that true wellbeing comes from integrating multiple "Zeno" practices into daily life. She developed ZenoWell's Five Pillars framework—Sleep, Food, Movement, Relaxation, and Vagus Nerve Regulation—a science-backed approach she personally lives by and shares with those around her.
Jane is dedicated to helping everyone feel better and live more—from family and friends to colleagues, research collaborators, patients, and ZenoWell users worldwide. Her mission is to make neuroscience-based wellness accessible, practical, and transformative for real people in real life.
Dr. Jane Xiao
Cofounder & Chief Scientist
The ZenoWell Dialogue
The ZenoWell Insight
How Do You Know ZenoWell Activates the Vagus Nerve?
We know many home remedies, activities, and products that claim to activate the vagus nerve, but can we prove it?
Yes, we can!
A recent study highlights that taVNS effectively modulates both the autonomic nervous system and the central nervous system.
Notably, a significant increase in heart rate variance (HRV) was observed in the majority of participants. Read more about it here.
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ZenoWell taVNS Journey Across Time
Four Mechanisms of ZenoWell’s taVNS
Restore ANS Balance and Modulate Neurotransmitter
Enhances parasympathetic activity while calming an overactive sympathetic activity, restoring balance to ANS.
Modulates the release of key neurotransmitters, including melatonin, serotonin, dopamine, endorphinsetal.
Modulating Brain Activity and Anti-inflammation Responses
Regulates activity and functional connectivity in brain regions associated with sleep, stress, and pain.
Reduces inflammation responses by activate 3 key anti-inflammatory pathways.
Experience Long-Lasting Effects
Scientifically designed electrodes and advanced materials deliver optimal and comfortable stimulation.
Consistent use brings long-lasting benefits: 7 days to reduce sleep latency, 14 days to improve sleep quality and reduce stress, and 21 days to refresh both body and mind.
Beyond Sleep Benefits
ZenoWell leverages cutting-edge neuromodulation technology to restore inner balance and support your body’s natural healing and recovery.
ZenoWell is your lifelong companion in wellness.
Clinical Studies of taVNS & ZenoWELL Patents
"ZenoWell's neurotechnology platform enhances cognitive focus, situational awareness, and sleep regulation through peer-validated, non-pharmaceutical methods that integrate seamlessly with circadian rhythms without adverse effects. Our ongoing clinical trials continue to confirm these breakthrough outcomes. For those interested in taVNS clinical and foundational research, we welcome collaboration inquiries."
























