Earth & HRV - Grounding and Heart Rate Variability
Heart rate variability (HRV) is the beat-to-beat change in heart rate. It reflects the autonomic nervous system (ANS), which governs heart rate, blood pressure, digestion, and other vital functions. The higher the HRV, the more flexible and adaptive the body is. The lower the HRV, the more stress or imbalance the body may be experiencing.
A study at a Neonatal Intensive Care Unit in Hershey, Pennsylvania, showed that grounding premature infants led to a quick improvement in ANS markers. These infants had an immediate increase in HRV, suggesting better vagal tone. This means grounding helped their delicate systems handle stress and inflammation more effectively.
Building on that, a 2011 study by Gaétan Chevalier, PhD and Stephen T. Sinatra, MD looked closer at the influence of grounding on HRV in adults. They recruited 24 subjects (14 men and 14 women). Each person acted as their own control. They sat in a reclining chair and were connected to a special TENS device designed for grounding. Four patches were placed on their soles and palms, with one electrode connected to the outdoor ground. A switch could toggle their connection, allowing a “real” grounding or a “sham” grounding setup.
The experimental sessions lasted two hours each and followed a randomized order: 40 minutes ungrounded, 40 minutes grounded or sham grounded, and 40 minutes ungrounded again. Researchers measured specific HRV parameters from ECG data:
SDRR (or SDNN): Standard deviation of R-R intervals. Higher SDRR means higher HRV, suggesting a healthier balance between sympathetic and parasympathetic systems. Low SDRR has been linked to conditions like heart disease, diabetes, and depression.
Spectral Components (via FFT of the R-R intervals):
Low Frequency (LF, 0.04–0.15 Hz): Influenced by both sympathetic and parasympathetic activity (often called sympatho-vagal balance).
High Frequency (HF, 0.15–0.4 Hz): Linked to vagal tone (parasympathetic activity).
Very Low Frequency (VLF, <0.04 Hz): Thought to be affected by processes like thermoregulation and hormonal patterns.
LF/HF Ratio: Used as an index of sympatho-vagal balance. A higher ratio suggests more sympathetic dominance. A lower ratio suggests more parasympathetic dominance.
According to Task Force HRV guidelines, these measures help describe ANS function. In the study, grounded subjects showed notable improvements. One subject was excluded for remaining grounded longer than the intended 40 minutes. Even so, the remaining data revealed that the grounded group’s HF increased by 63%, compared to a 33% increase in non-grounded controls. LF increased by 68% vs 28% in controls. SDRR rose by 50% vs 20%. LF/HF ratio stayed level for grounded participants, indicating that LF and HF rose together because of parasympathetic dominance.
This means grounding more than doubled the parasympathetic (rest/digest) effect, supercharging relaxation beyond what the insulated group experienced. Grounded subjects had greater calmness, improved HRV, and enhanced vagal tone. These findings match earlier observations from a meditation study, where HRV was also measured:
Subject 1: LF & HF moved in tandem, both declining then peaking 25 min into grounding, then dropping, then rising again. This pattern suggested natural ANS fluctuations, possibly linked to healing.
Subject 6: LF was usually higher than HF, except at the start and mid-grounding. The shift toward higher HF in the middle implied deep relaxation.
Subject 7: HF was larger than LF during grounding, even with some electrode discomfort. This showed an ability to relax fully while grounded.
Subject 8: HF became much larger than LF after the first few minutes, reflecting strong relaxation and steady meditation for nearly the entire session.
These investigations emphasize grounding’s capacity to enhance HRV. We see a consistent theme of increased parasympathetic activity, stronger vagal tone, and deeper relaxation. HRV itself is a key predictor for cardiovascular risk. Low HRV or shifts in autonomic function can foreshadow serious events like arrhythmias or sudden cardiac death. Methods that improve HRV offer a powerful support for heart health.
Clinicians can now add grounding to their toolbox for raising HRV. This free, simple method involves direct contact with the Earth. Research highlighted here and in Earth & Water has shown that it can benefit infants, healthy adults, and even individuals practicing meditation. Earth & HRV reveals how our connection to the ground can help align and balance the body’s electric and autonomic processes.
If you’re interested in learning more about grounding, check out Earth & Water.
Further Reading:
Shaffer, F., & Ginsberg, J. P. (2017). An overview of heart rate variability metrics and norms. Frontiers in public health, 5, 258. doi: 10.3389/fpubh.2017.00258.
Perini R, Veicsteinas A. Heart rate variability and autonomic activity at rest and during exercise in various physiological conditions. Eur J Appl Physiol. 2003;90(3-4):317-325
Chevalier, Gaetan. (2022). The Effects of Grounding on Meditation Quality: Preliminary Study Report—A Case Series. Energy Psychology. 14. 13-50. 10.9769/EPJ.2022.14.2.GC.
Fang S-C, Wu Y-L, Tsai P-S. Heart Rate Variability and Risk of All-Cause Death and Cardiovascular Events in Patients With Cardiovascular Disease: A Meta-Analysis of Cohort Studies. Biological Research For Nursing. 2020;22(1):45-56. doi:10.1177/1099800419877442
Chevalier, Gaetan & Sinatra, S.T.. (2011). Emotional stress, heart rate variability, grounding, and improved autonomic tone: clinical applications. 10. 16-21.
