Heart Rate Variability Podcast

Episódios

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  This Week in HRV — Episode 55 15.09.2026 51min

  Medical Disclaimer: The information shared on This Week in HRV is for educational purposes only and is not intended as medical advice. Always consult a qualified healthcare professional before making changes to your health routine. This week on This Week in Heart Rate Variability, we explore the theme of Medical — studying HRV across populations dealing with identifiable disease states and clinical questions. From noise exposure in everyday life to smoking, cardiac surgery rehabilitation, rare autoimmune disease, AI-powered sleep staging, and physical activity in chronic lung disease, today's research spans the full clinical spectrum of what HRV can tell us. 1. Every 10 dB increase in environmental noise reduces SDNN by up to 16% over 160 minutes: evidence from the Apple Hearing Study PUBLICATION: Journal of Exposure Science and Environmental Epidemiology (Nature Portfolio)AUTHORS: Xin Zhang, Sung Kyun Park, Lauren M. Smith, and Richard L. Neitzel KEY FINDING: Using wearable-derived SDNN and sound-exposure data from roughly 980–1,180 participants per analysis in the Apple Hearing Study, hierarchical Bayesian distributed-lag models found that each 10 dB increase in environmental noise was associated with an overall SDNN reduction of 6.8% over a short-term (20-minute) window and 16.0% over a long-term (160-minute) window. Headphone sound produced smaller, more consistent reductions of 7.1–7.4% regardless of window length. Reductions were greater in older adults and those with tinnitus. SIGNIFICANCE: This elevates noise — including overnight traffic noise and headphone volume — to the same level of concern as sleep quality, training load, and nutrition in shaping HRV. The data also provides context for unexpectedly low morning HRV readings after noisy nights. Read the full study 2. Ambulatory monitoring reveals what office readings miss: smokers have heart rates nearly 7 bpm higher in daily life — and elevated diastolic blood pressure PUBLICATION: Hypertension Research (Nature Portfolio)AUTHORS: Yuya Akagi, Kimika Arakawa, Atsushi Sakima, Mai Kabayama, Ken Sugimoto, Yuichi Akasaki, Ako Fukami, Satoko Sakata, Hirochika Ryuno, Hiroyuki Kadoya, Toshiya Yamamoto, Hiroko Yoshida, Yoichi Nozato, Taisuke Ueno, Makiko Abe, Hisatomi Arima, Mitsuru Ohishi, Nobuhito Hirawa, Chisa Matsumoto, Shin-Ichiro Miura, Masaki Mogi, Akira Nishiyama, Akihiro Nomura, Takayoshi Ohkubo, Yusuke Ohya, Shigeru Shibata, Yasuharu Tabara, Koichi Yamamoto, and Kazuomi Kario KEY FINDING: This systematic review and meta-analysis of four non-randomized crossover comparative studies (104 participants total) compared ambulatory blood pressure and heart rate within the same current smokers during active smoking versus abstinence periods (1 day to 1 week). Twenty-four-hour diastolic blood pressure was 2.67 mmHg higher during smoking (95% CI 0.72–4.62), and daytime diastolic was 3.17 mmHg higher. Twenty-four-hour heart rate was 6.47 bpm higher during smoking (95% CI 3.98–8.96); daytime 7.19 bpm higher; nighttime 3.58 bpm higher. Systolic blood pressure showed no significant difference between periods. SIGNIFICANCE: This helps explain the long-standing office blood pressure paradox in smokers: they appear similar to non-smokers in clinical readings because they abstain before appointments and are at rest. Ambulatory monitoring reveals the true picture — persistent sympathetic arousal manifesting as chronically elevated heart rate around the clock. For HRV practitioners, this means a smoking patient's measured baseline is not their true autonomic baseline, and it positions HRV tracking as a motivational tool in cessation progra...
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  Brainwave Entrainment, HRV & Nervous System Optimization with Dr. Patrick Porter 10.09.2026 53min

  In this episode of the Heart Rate Variability Podcast, Matt Bennett sits down with Dr. Patrick K. Porter, PhD, founder of BrainTap®, to explore the connection between brainwave activity, heart rate variability, breathwork, and nervous system regulation. Dr. Porter shares how his interest in brainwave training began at an early age and how decades of work in neuroscience-based performance ultimately led to the development of BrainTap. His background includes extensive work in brainwave entrainment and non-invasive approaches to supporting brain health and human performance. In this conversation, Matt and Dr. Porter discuss how HRV can be used as a practical measure of nervous system activity, why chronic high-stress states may affect cognitive performance and recovery, and how intentional practices can help shift the body toward more regulated states. They also explore:- Brainwave states including beta, alpha, theta, gamma, delta, and SMR- The relationship between HRV, brain activity, and autonomic regulation- Brainwave entrainment compared with neurofeedback- Breathwork practices for different times of the day- Vagal stimulation and simple nervous-system regulation techniques- BrainTap research related to pain, stress, cognitive performance, and recovery- Dr. Porter’s personal routine for supporting brain and nervous system health- How AI may influence the future of personalized brain fitness Dr. Porter also shares his perspective on where brain optimization is headed—from clinics and universities to schools, workplaces, and personalized digital coaching. Whether you’re interested in HRV, neuroscience, biofeedback, breathwork, stress regulation, or improving human performance, this conversation offers a fascinating look at how the brain and autonomic nervous system may work together. Learn more about Optimal HRV: https://www.optimalhrv.comLearn more about BrainTap: https://braintap.com This podcast is for educational purposes only and is not intended to provide medical advice, diagnosis, or treatment.
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  This Week in HRV — Episode 54 08.09.2026 1h 14min

  Medical disclaimer: The information shared on this podcast is for educational and informational purposes only. It is not intended as medical advice and should not be used as a substitute for professional guidance from a qualified healthcare provider. If you have questions about your health or a medical condition, please consult a licensed clinician who knows you and your history. This week on This Week in Heart Rate Variability, we explore the theme of Performance. Seven studies this week cover urban air pollution, shift work, weighted vests, functional clothing, ergogenic supplementation, elite athlete aging, and real-time exercise intensity classification with DFA-alpha-1. RESEARCH HIGHLIGHTS THIS WEEK 1. Combined mask and headphone use significantly improves HRV during traffic exposure: a randomized crossover RCT PUBLICATION: Journal of Hazardous MaterialsAUTHORS: Meng, Qi, Wang, and Duan KEY FINDING: In a randomized crossover study, 51 healthy young adults (mean age 20, ~40% female) were exposed to four 2-hour conditions at a high-traffic site in Beijing: no intervention, KN95 mask alone, noise-canceling headphones alone, and both combined. Single interventions did not yield a significant HRV benefit. The combined intervention significantly elevated SDNN (+20.3%), RMSSD (+56.8%), SDSD (+62.0%), pNN50 (+61.1%), LF (+128.6%), and HF (+73.8%) relative to control. It also reduced the myocardial injury marker CK-MB by 27.6% and homocysteine by 79.5%. Females showed greater autonomic benefits than males. SIGNIFICANCE: This finding has real implications for urban athletes and anyone training in polluted environments. Wearing just one intervention (mask or headphones) alone did not provide significant protection, but the combined approach demonstrated robust cardiovascular protection during traffic exposure. Read the full study 2. Night shift workers show elevated heart rate fragmentation independent of traditional HRV changes: MESA Sleep cohort PUBLICATION: Chronobiology InternationalAUTHORS: Multi-Ethnic Study of Atherosclerosis Sleep study cohort analysis KEY FINDING: A cross-sectional analysis of 845 participants (mean age 64, 51% women) compared heart rate variability and heart rate fragmentation (HRF) across shift types. Night and rotating shift workers had significantly higher PAS - the percentage of normal-to-normal intervals in alternation segments - compared to day workers (+11.9%, 95% CI 1.8-22.0). Traditional HRV metrics showed minimal and inconsistent differences. Sleep duration modified the effect: the PAS difference was most pronounced in short sleepers (+20.4%) and reversed in long sleepers (-10.8%, interaction p=0.06). SIGNIFICANCE: The surprising finding is that traditional HRV showed almost no difference between night-shift and day-shift workers. But a newer metric called heart rate fragmentation - specifically PAS, the percentage of intervals in alternation segments - was significantly elevated in night/rotating shift workers. Sleep duration modulated the severity of that fragmentation, suggesting that this metric captures autonomic stress that standard HRV indices miss. Read the full study 3. Weighted vest use increases cardiovascular workload and transiently suppresses HRV during active wearing, with more pronounced effects in females: ATLAS RCT sub-study PUBLICATION: Physiological ReportsAUTHORS: Bellman, PA Jansson, JO Jansson, Ohlsson, and Bergfe...
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  This Week in HRV - Episode 53 01.09.2026 48min

  Medical disclaimer: The information shared on this podcast is for educational and informational purposes only. It is not intended as medical advice and should not be used as a substitute for professional guidance from a qualified healthcare provider. If you have questions about your health or a medical condition, please consult a licensed clinician who knows you and your history. This week on This Week in Heart Rate Variability, we open a new themed month by looking at where heart rate variability is headed next. Six studies map the future of the field — from a unifying theory of cardiovascular instability built on Shannon entropy, to the regulatory and technical realities of validating consumer wearables, to a meta-analysis quantifying how far photoplethysmography still is from true electrocardiography-derived HRV, to a virtual reality study, a forest-based multimodal field study, and a deep dive into the asymmetric structure of the heartbeat itself. RESEARCH HIGHLIGHTS THIS WEEK 1. Shannon Entropy in Heart Rate Variability: A Unified Indicator of Electrical and Hemodynamic Cardiovascular Instability PUBLICATION: Medical Research Archives AUTHORS: Orazio Antonio Barra KEY FINDING: This systematic review pooled 22 published studies that applied Shannon entropy of RR intervals to atrial fibrillation and tilt-induced syncope. Entropy declined progressively across both conditions — roughly ten percent at baseline instability, fifteen to twenty percent approaching pre-crisis, and twenty-five to thirty percent as crisis became imminent — with entropy showing better specificity than other HRV indices while holding onto its sensitivity. SIGNIFICANCE: Entropy looks less like a metric tied to one specific condition and more like a general-purpose marker of autonomic complexity loss that shows up consistently whether the underlying instability is electrical or hemodynamic. This is a synthesis of existing studies rather than a new trial, so it should be read as a strong, well-supported hypothesis rather than a validated bedside tool. Read the full study: https://esmed.org/MRA/mra/article/view/7606 2. Validity, Reliability, and Regulatory Considerations for Consumer Devices in Clinical Research Data Collection PUBLICATION: Applied Clinical Trials Online AUTHORS: Lauren Crooks, Greta Marie van Schoor, Anthony Everhart, Bill Byrom, and Thijs Sondag KEY FINDING: This article maps the validity, reliability, and regulatory landscape for consumer wearables used in decentralized clinical trials. Heart rate accuracy can approach ECG-level concordance under favorable conditions, but motion artifacts, device-to-device variation, and demographic performance gaps can cause aggregate agreement statistics to mask large individual-level errors. Only an estimated 11% of devices on the market have been rigorously and publicly validated. SIGNIFICANCE: Regulators are converging on "fit-for-purpose" validation rather than universal accuracy claims — asking whether a specific device is accurate enough for a specific clinical question, not whether it's accurate for everything. That's a useful discipline for anyone using consumer devices outside a formal trial, too. Read the full study: https://www.appliedclinicaltrialsonline.com/view/validity-reliability-regulatory-considerations-consumer-devices-clinical-research-data-collection 3. Accuracy of Photoplethysmography-Derived Pulse Rate Variability Compared with Electrocardiography-Derived Heart Rate Variability: A Systematic R...
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  Lieven Van Linden talk the English Release of Fully Charged and Continued Work in HRV 27.08.2026 40min

  In this follow-up episode of the Heart Rate Variability Podcast, Matt Bennett reconnects with Lieven Van Linden to discuss the newly published English version of his book, Fully Charged. Since their last conversation two years ago, Lieven’s work has continued to evolve at the intersection of leadership, nervous system regulation, sustainable performance, and HRV. Lieven shares how his engineering background shaped the framework behind Fully Charged, applying process improvement thinking to human performance. Rather than treating energy, resilience, and leadership as vague concepts, his model looks at the body as a system with inputs, processes, outputs, and measurable feedback. HRV plays a central role as a biomarker for nervous system health, recovery, and available energy. Matt and Lieven also explore what has changed since the book's original publication, including new English-language chapters on artificial intelligence and women's energy levels. Lieven reflects on the slower-than-expected adoption of HRV technology in Europe and the growing conversation around AI health coaches. While AI can support education and insight, Lieven emphasizes that human connection remains essential for lasting behavioral change. The conversation also moves into Lieven’s personal evolution. After years of extreme endurance racing, he has shifted toward freediving, which challenges him in a very different way. Rather than pushing through suffering, freediving requires relaxation, self-regulation, inner awareness, and trust in the body.
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  This Week in HRV - Episode 52 25.08.2026 42min

  Medical disclaimer: The information shared on this podcast is for educational and informational purposes only. It is not intended as medical advice and should not be used as a substitute for professional guidance from a qualified healthcare provider. If you have questions about your health or a medical condition, please consult a licensed clinician who knows you and your history. This week on This Week in Heart Rate Variability, we open our second themed month with a focus on medical health. Six studies map how heart rate variability behaves under real medical strain — from a rigorous methodological look at glucose sensing, to a two-decade cohort tracking cardiovascular mortality, to hidden autonomic signals in normal brain recordings, to the flattening and even reversal of breath-heart coupling in brain-injured intensive care patients, to a call for multi-window autonomic assessment in critically ill cancer patients, and finally to autonomic flexibility as a biomarker for fatigue in multiple sclerosis. A quick reminder that this is the newly curated, theme-based format we kicked off last month, and this week's center of gravity is medical health. RESEARCH HIGHLIGHTS THIS WEEK 1. Re-evaluating heart rate variability biomarkers for glucose sensing: the impact of age normalization and subject-independent validation PUBLICATION: BMC Medical Informatics and Decision Making AUTHORS: Md Basit Azam, Sarangthem Ibotombi Singh KEY FINDING: In a rigorously validated model built on data from forty-three men with type two diabetes, heart rate variability features derived from the electrocardiogram showed a modest but significant association with hemoglobin A1c (R-squared of about zero point two two), while none of the six tested age-normalization methods improved model performance — suggesting age-related decline in heart rate variability was not confounding the signal. SIGNIFICANCE: This study is a piece of methodological conscience in the wearable glucose monitoring space. It shows that heart rate variability carries a real but modest signal for glycemic status, that honest subject-independent validation is essential, and that a fashionable statistical correction is not worth adding until you have checked whether it actually helps. Read the full study: https://pmc.ncbi.nlm.nih.gov/articles/PMC13169770/ 2. Differential associations of resting heart rate and heart rate variability indices with cardiovascular and coronary heart disease mortality risk: the prospective KORA study PUBLICATION: Scientific Reports AUTHORS: Kolade Oluwagbemigun, Dan Ziegler, Alexander Strom, Margit Heier, Gidon J. Bönhof, Michael Roden, Wolfgang Rathmann, Christa Meisinger, Annette Peters, Stefanie M. Hauck, Agnese Petrera, Moritz F. Sinner, Stefan Kääb, Barbara Thorand, Christian Herder KEY FINDING: In a prospective German cohort followed for more than two decades, higher resting heart rate was associated with greater cardiovascular and coronary heart disease mortality across the whole group, while the relationships between heart rate variability indices and mortality differed by glucose status — including an S-shaped, nonlinear association between the root mean square of successive differences and cardiovascular mortality in people with type two diabetes. SIGNIFICANCE: The metabolic context changes the meaning of the measurement. The same heart rate variability index does not convey the same message in a person with normal blood sugar as in a person with diabetes, and greater variability is not always better. Long-cohort work like this reframes heart rate variability as a context-dependent marker rather than a univ...
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  This Week in HRV - Episode 51 18.08.2026 44min

  Medical disclaimer: This podcast is for informational and educational purposes only and does not constitute medical advice. Please consult your healthcare provider before making any changes based on this content. Welcome to This Week in Heart Rate Variability. This is the next installment in our newly curated, theme-based format, and this week's theme is mental health: what the rhythm of the heart can—and cannot—tell us about the mind. Across seven studies, a single thread keeps surfacing: the body's story and the mind's story refuse to line up neatly. Sometimes lower heart rate variability marks distress; sometimes it does not move where we most expect it to; and in at least one striking case, higher variability marks not health but trouble. RESEARCH HIGHLIGHTS THIS WEEK 1. A meta-analysis of heart rate variability and psychopathology: An investigation guided by the hierarchical taxonomy of psychopathology framework PUBLICATION: Journal of Psychopathology and Clinical Science AUTHORS: Tam Pham, Carly J. Johnco, Ana Neves, Wilson P. H. Lim, Gladys J. Heng, Rachel Ygnacio, Miriam K. Forbes KEY FINDING: Pooling 430 studies (732 effect sizes across roughly 62,000 people), lower resting heart rate variability was associated with most of the psychopathology hierarchy — including schizophrenia, bipolar disorder, autism, generalized anxiety disorder, panic disorder, borderline personality disorder, post-traumatic stress disorder, and major depression — but not with obsessive-compulsive disorder, social anxiety disorder, or attention-deficit/hyperactivity disorder. Associations were strongest in psychotic conditions and consistently stronger in more severely symptomatic samples. SIGNIFICANCE: Reduced heart rate variability looks less like a disorder-specific fingerprint and more like a transdiagnostic marker of systemic dysregulation tied to illness severity — a fever, not a rash. It may be most useful for gauging overall strain and tracking change over time rather than sorting people into diagnoses. This is a meta-analysis of largely cross-sectional data, so it shows association, not causation. Read the full study: https://pubmed.ncbi.nlm.nih.gov/42490257/ 2. Heart rate variability and risk of agitation in Alzheimer's disease: the Atherosclerosis Risk in Communities Study PUBLICATION: Brain Communications AUTHORS: Kathy Y. Liu, Eric A. Whitsel, Gerardo Heiss, Priya Palta, Suzanne Reeves, Feng V. Lin, Mara Mather, Jonathan P. Roiser, Robert Howard KEY FINDING: In 120 participants from the Atherosclerosis Risk in Communities study whose dementia was attributed solely to Alzheimer's disease, higher heart rate variability was associated with greater agitation risk, with the strongest signal coming from the change in vagally mediated variability over roughly two decades. The associations were adjusted for cognitive status, resting heart rate, demographics, comorbidities, and medications affecting the autonomic nervous system. SIGNIFICANCE: The meaning of heart rate variability is context-dependent: in a brain undergoing neurodegeneration, an increase in autonomic signal may reflect a loss of regulatory control rather than resilience. This is a candidate marker of propensity for agitation, not yet a clinical tool. Observational design and a small subgroup mean this is association, not causation. Read the full study: https://academic.oup.com/braincomms/article/5/6/fcad269/7311113?login=false 3. Physiological correlates of interoception and the effect of heart rate variability biofeedback ...
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  Karen "Zuzu" Armes talks HRV, GABA, and Gut Health 13.08.2026 59min

  In this episode of the Heart Rate Variability Podcast, Matt Bennett speaks with Zuzu Karen Arms about the deep connection between gut health, the autonomic nervous system, and heart rate variability. Zuzu shares her personal journey of reversing epilepsy, scoliosis, and other health challenges through holistic approaches. The conversation explores how the gut microbiome supports nervous system regulation, why GABA production matters, and how gut health may influence conditions like POTS, dysautonomia, and low HRV. Matt and Zuzu also discuss nutrition, fiber, probiotics, prebiotics, acupuncture, biofeedback, and the importance of creating the right internal environment for better autonomic balance. Topics Covered Zuzu’s personal health journey and holistic recovery The relationship between gut health and the autonomic nervous system How the microbiome influences HRV and nervous system regulation GABA production in the gut and why it matters POTS, dysautonomia, and nervous system imbalance Dietary approaches for supporting gut and nervous system health Why processed carbohydrates may negatively affect GABA levels The role of fiber, prebiotics, and probiotics Maintaining healthy gut pH Acupuncture and biofeedback as supportive therapies Rethinking the modern emphasis on protein consumption Key Takeaways Gut health plays a major role in nervous system regulation, and the microbiome may directly influence HRV through mechanisms like GABA production, inflammation, and autonomic signaling. Zuzu emphasizes that supporting the gut is not just about digestion. It can also affect energy, neurological function, emotional regulation, cardiovascular control, and resilience. The discussion also challenges common nutrition assumptions, including the overemphasis on protein intake, while highlighting the importance of plant-based nutrients, fiber, and gut-friendly dietary patterns.
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  This Week In HRV – Episode 50 11.08.2026 47min

  Medical disclaimer: This podcast is for informational and educational purposes only and does not constitute medical advice. Please consult your healthcare provider before making any changes based on this content. Ethical Principles and Practice Standards in Clinical Biofeedback with Dr. Donald Moss — 3 APA CE credits, BCIA-aligned https://www.optimalhrv.com/event-details-registration/master-ethical-principles-practice-standards-in-clinical-biofeedback-aligned-with-bcia This Week in Heart Rate Variability. This is a milestone edition — our 50th episode in the This Week in HRV format, and the start of a more curated approach that organizes episodes around themes rather than publication timing. We begin that new chapter with performance, following the autonomic nervous system across five studies: from whether burnout leaves a measurable mark on the working heart, to the quiet self-talk that sharpens a golfer's focus, to hydrogen-rich water and faster recovery, to syncing breath with heartbeat at the edge of exhaustion, and finally to a blueprint for building biofeedback into how athletes train. RESEARCH HIGHLIGHTS THIS WEEK 1. What Your Heart Reveals About Workplace Burnout PUBLICATION: Frontiers in Physiology AUTHORS: Irina Böckelmann, Jonas Hartung, Sabine Darius, Stefan Sammito, Beatrice Thielmann KEY FINDING: In 202 employees working in interaction-heavy jobs — nursery teachers, bank clerks, and medical assistants — only about 5 percent showed elevated burnout risk. Where heart rate variability differed by burnout risk, the differences showed up in the 24-hour and daytime recordings but not during sleep, and the correlations between HRV and burnout were mostly weak. Age and gender influenced HRV more than burnout status did. SIGNIFICANCE: This is a cross-sectional study, so it can show association but not causation — it cannot tell us that burnout changes HRV or the reverse. Still, the pattern hints that if HRV is going to reflect occupational strain, daytime and on-the-job recordings may be more sensitive than overnight data. For now, HRV looks like a possible complement to validated burnout questionnaires, not a standalone screening tool. Read the full study: https://www.frontiersin.org/journals/physiology/articles/10.3389/fphys.2026.1908141/full 2. How Self-Talk Quietly Sharpens Focus Under Pressure PUBLICATION: Behavioral Sciences AUTHORS: Emmanouil Tzormpatzakis, Theodoros Proskinitopoulos, Orestis Panoulas, Evangelos Galanis, Evgenia Nikolakopoulou, Nikos Comoutos, Yannis Theodorakis, Antonis Hatzigeorgiadis KEY FINDING: Forty novice golfers were split into a control group and a group trained in strategic self-talk. The self-talk group improved their putting significantly more and outperformed the control group at the final assessment, while showing greater parasympathetic activation (in the root mean square of successive differences), especially toward the later stages of the task. The authors note the HRV pattern did not reach multivariate significance. SIGNIFICANCE: The physiological signal fits an attentional explanation: self-talk may help performers execute with less mental effort, keeping the rest-and-digest system more engaged under pressure. Strategic self-talk is a low-cost, teachable tool that appears to accelerate skill learning. The performance benefit is solid; the HRV mechanism...
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  This Week In HRV - Episode 49 04.08.2026 53min

  Medical disclaimer: This podcast is for informational and educational purposes only and does not constitute medical advice. Please consult your healthcare provider before making any changes based on this content. Ethical Principles and Practice Standards in Clinical Biofeedback with Dr. Donald Moss — 3 APA CE credits, BCIA-aligned https://www.optimalhrv.com/event-details-registration/master-ethical-principles-practice-standards-in-clinical-biofeedback-aligned-with-bcia This Week in Heart Rate Variability. In this episode, we trace the autonomic nervous system across an entire human lifespan — from a mother's anxiety reaching her baby's heart in the womb, to ADHD and the "vagal brake," to a middle school experiment on weight stigma and peer support, to how your menstrual cycle quietly reshapes your heart rhythm, all the way to AI models learning to forecast your next heartbeat. RESEARCH HIGHLIGHTS THIS WEEK 1. Does Mom's Anxiety Change Baby's Heartbeat? It Depends on Baby's Sex PUBLICATION: Journal of Affective Disorders AUTHORS: Anna M. Zhou, Sarah E. Maylott, Nicolette C. Molina, Dylan Neff, Elisabeth Conradt, Sheila E. Crowell KEY FINDING: In 159 mother-fetus pairs, higher maternal anxiety was linked to elevated fetal heart rate specifically in male fetuses, not female ones. Broader maternal depression and anxiety symptoms were tied to lower fetal heart rate variability regardless of fetal sex. SIGNIFICANCE: This suggests prenatal maternal mental health shapes fetal autonomic development in sex-specific ways, reinforcing why prenatal mental health screening matters for the baby, not just the mother. Read the full  study: https://www.sciencedirect.com/science/article/abs/pii/S0165032726011833 2. What Your Heart Rate Reveals About ADHD (And What It Doesn't) PUBLICATION: Middle East Current Psychiatry AUTHORS: Davoud Amiri, Lamberto Briziarelli, Swetang J. Shah, Sara Amiri, Hadi Rahimi-Danesh KEY FINDING: This clinical review found that reduced heart rate variability in ADHD shows up most consistently under cognitive or emotional stress, not at rest, with wide variation driven by age, medication status, and coexisting anxiety. SIGNIFICANCE: The authors propose a "phenotype-informed" framework linking autonomic profiles to emotional dysregulation and medication tolerability — a promising but still hypothesis-generating direction, not a diagnostic tool. Read the full study: https://link.springer.com/article/10.1186/s43045-026-00658-7 3. The Middle School Study That Shows Why Peer Support Protects the Heart PUBLICATION: Adolescents AUTHORS: Meghan J. Gangel, Daniel Hamill, Alleyne P. R. Broomell KEY FINDING: In 31 middle schoolers, internalized weight stigma alone didn't predict stress reactivity — but among adolescents with low peer acceptance, higher weight stigma triggered a significantly larger sympathetic stress response. High peer acceptance eliminated that effect entirely. SIGNIFICANCE: Peer belonging may physiologically buffer adolescents from the harms of internalized weight stigma, suggesting interventions should target social acceptance, not just body-image beliefs, on thei...
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  Dr. Diana Driscoll on POTS, HRV, Autonomic Health, and Recovery 30.07.2026 46min

  In this episode of the Heart Rate Variability Podcast, Matt Bennett speaks with Dr. Diana Driscoll about her work in autonomic health, POTS, inflammation, and recovery from complex chronic illness. Dr. Driscoll shares her journey from optometrist to patient-researcher after developing POTS following a viral illness. When traditional medical care failed to help her and her family, she began investigating the underlying causes of autonomic dysfunction. She explains why she views POTS not as a single disease, but as a presentation of deeper issues involving inflammation, neurotransmitter disruption, cardiovascular problems, intracranial pressure, and genetic predispositions. The conversation also explores her development of Parasym Plus and her recovery-focused approach to treatment. Matt and Dr. Driscoll discuss how HRV can be used to track autonomic function and recovery over time, as well as the importance of persistence, proactive care, and continuing to search for answers. Topics Discussed Dr. Driscoll’s personal experience with POTS Why POTS may be a presentation, not a disease Inflammation and autonomic dysfunction Parasympathetic nervous system function Parasym Plus and neurotransmitter support HRV as a tool for tracking recovery Why Dr. Driscoll believes many patients can improve significantly Key Takeaway Dr. Driscoll offers a recovery-focused view of POTS and autonomic dysfunction, emphasizing the importance of identifying and treating the underlying causes rather than only managing symptoms.
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  This Week In HRV - Episode 48 28.07.2026 49min

  Medical disclaimer: This podcast is for informational and educational purposes only and does not constitute medical advice. Please consult your healthcare provider before making any changes based on this content. BCIA HRV Biofeedback Training with Dr. Inna Khazan — 16 APA CE credits https://www.optimalhrv.com/event-details-registration/bcia-aligned-hrv-biofeedback-training-led-by-dr-inna-khazan Ethical Principles and Practice Standards in Clinical Biofeedback with Dr. Donald Moss — 3 APA CE credits, BCIA-aligned https://www.optimalhrv.com/event-details-registration/master-ethical-principles-practice-standards-in-clinical-biofeedback-aligned-with-bcia This week Matt covers seven new studies spanning psychiatry, neurology, endocrinology, and sports science — from a systematic review mapping how heart rate variability is used across clinical research, to adolescent depression, suicide risk, music and athletic recovery, seizure disorders, and two studies on diabetes. It's a dense, wide-ranging episode with real implications for clinicians, coaches, and researchers alike. RESEARCH HIGHLIGHTS THIS WEEK 1. Application of heart rate variability in clinical practice and research: A systematic review of recent years PUBLICATION: Autonomic Neuroscience: Basic and Clinical AUTHORS: Camila Maldonado-Veas, Paula León, Claudia Lerma, and Juan C. Echeverría KEY FINDING: This systematic review screened recent heart rate variability literature to catalog how HRV indices are applied for diagnosis, severity staging, and disease tracking across cardiovascular, neurological, and psychiatric conditions. The authors found substantial inconsistency in which indices are reported and how confounding variables are handled across studies. SIGNIFICANCE: The authors propose a standardized roadmap for selecting and interpreting heart rate variability indices in future research, arguing that greater methodological consistency is needed before findings across studies can be meaningfully compared. Read the full study: https://cardiovasculardynamicslab.com/en/aplication-of-heart-rate-variability-in-clinical-practice-an-research-a-systematic-review-of-recent-years/ 2. Divergence of clinical and autonomic recovery in adolescent major depressive disorder: A 10-week prospective heart rate variability study with nocturnal electrocardiogram monitoring PUBLICATION: Journal of Affective Disorders AUTHORS: Haisi Chen, Xiaona Zhang, Shuning Hong, Zhenghe Yu, and Wanlin Chen KEY FINDING: In forty-three adolescent inpatients with major depressive disorder followed for ten weeks of routine treatment, depression and anxiety symptoms improved significantly, but only about seven percent achieved early clinical response. Heart rate variability deficits present at baseline did not normalize, and autonomic function instead shifted further toward sympathetic dominance by the end of the study. SIGNIFICANCE: Clinical symptom improvement and autonomic recovery may follow independent tracks in adolescent depression. Reduced somatic anxiety was associated with less sympathetic deterioration, though this reflects a correlation rather than evidence that...
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  This Week In HRV - Episode 47 21.07.2026 50min

  DISCLAIMER: This podcast and its accompanying show notes are for educational and informational purposes only and are not a substitute for professional medical, psychological, or clinical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare professional with any questions you may have regarding a medical condition. Dr. Inna Khazan's HRV Biofeedback Training (BCIA-aligned, 16 APA CE credits) Registration Link: https://www.optimalhrv.com/event-details-registration/bcia-aligned-hrv-biofeedback-training-led-by-dr-inna-khazan Dr. Donald Moss's Ethical Principles and Practice Standards in Clinical Biofeedback (BCIA-aligned, 3 APA CE credits)  Registration Link: https://www.optimalhrv.com/event-details-registration/master-ethical-principles-practice-standards-in-clinical-biofeedback-aligned-with-bcia This week we cover five studies that stretch heart rate variability into some surprising territory. We start with elite wrestlers and what heart rate variability reveals about training recovery, move into the modern office to look at heart rate variability as an objective marker of musculoskeletal pain risk, and head into neurology for two studies on seizure diagnosis and unexplained neurological symptoms. We close with a study on sound your ears can't consciously hear, but your nervous system apparently can. RESEARCH HIGHLIGHTS THIS WEEK 1. Investigating the Acute Effect of Different Training Protocols on Heart Rate Variability PUBLICATION: Sports AUTHORS: Burhan Demirkıran, Tuba Melekoğlu, Grzegorz Żurek KEY FINDING: In thirteen elite Greco-Roman wrestlers, both high-intensity interval training and prolonged endurance training produced dramatic acute suppression of heart rate variability, with SDNN dropping seventy-three to eighty-two percent immediately after exercise, followed by partial recovery at the twenty-four-hour mark. After correcting for multiple comparisons, there was no statistically significant difference between the two training protocols. SIGNIFICANCE: Coaches often assume that different training modalities carry meaningfully different acute costs to the nervous system, but this study suggests that intense effort of either type may impose a comparable autonomic burden, at least in this population and time frame. That has real implications for how training loads are planned in the days leading up to competition. Read full study: https://www.mdpi.com/2075-4663/14/7/299 2. Heart Rate Variability as an Objective Biomarker for Work-Related Musculoskeletal Disorder Risk: A Cross-Sectional Study of Hong Kong (China) Professionals PUBLICATION: Exploration of Musculoskeletal Diseases AUTHORS: Adrian Low, Benny Lam KEY FINDING: In 105 Hong Kong office professionals, lower heart rate variability coherence was associated with higher musculoskeletal pain intensity and a broader spread of pain across the body, even after accounting for self-reported stress. Forward head posture and thoracic kyphosis helped explain part of the relationship between coherence and neck and shoulder pain, and daily sedentary hours changed the strength of the overall association. SIGNIFICANCE: This cross-sectional study points to heart rate variability coherence a...
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  Debunking the LF/ HF Ratio Myth with Dr. Fred Shaffer 16.07.2026 47min

  Join host Matt Bennett and Dr. Fred Shaffer on the Heart Rate Variability Podcast as they debunk common misconceptions about the low-frequency to high-frequency (LF/HF) ratio. Dr. Shaffer explains how short-term low-frequency power more accurately reflects blood pressure regulation than sympathetic tone, and clarifies that everyday stress is often simply vagal withdrawal rather than a true fight-or-flight sympathetic response. He also recommends more reliable metrics for assessing autonomic balance, such as RMSSD. Finally, the episode introduces Mentor, a custom AI tool rigorously trained on peer-reviewed biofeedback and HRV research, designed to serve as a reliable, 24/7 educational tutor for both practitioners and enthusiasts.
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  This Week In HRV - Episode 46 13.07.2026 51min

  DISCLAIMER: This podcast and its accompanying show notes are for educational and informational purposes only and are not a substitute for professional medical, psychological, or clinical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare professional with any questions you may have regarding a medical condition. This week we're covering eight new studies spanning addiction, psychiatry, neonatal care, occupational health, women's health, and exercise science. You'll hear how alcohol cues and stress pull on heart rate variability in different directions, how short-term heart rate variability tracked suicide risk in hospitalized patients, how much a simple change in posture shifts your numbers, and more. As always, we break down what each study actually found, what it means for your practice, and where the caveats live. RESEARCH HIGHLIGHTS THIS WEEK 1. The link between subjective feelings (arousal and craving) and physiological responses (heart rate variability) in stress- and alcohol cue-reactivity among young adults engaged in hazardous drinking: a counterbalanced study PUBLICATION: Addictive Behaviors AUTHORS: Insan Firdaus, Annet Kleiboer, Anne Marije Kaag, Anja C. Huizink KEY FINDING: In 56 young hazardous drinkers, handling an alcoholic beverage increased both craving and heart rate variability, while a mental arithmetic stress task raised subjective stress without increasing craving at all. When the stress task came first, exposure to the alcohol cue afterward actually lowered perceived stress. SIGNIFICANCE: Craving and stress don't always move together, which means "avoid your triggers" may be an incomplete relapse-prevention strategy. Alcohol cues may function as a short-term emotional reset for some hazardous drinkers, independent of craving itself. Read the full study:  https://www.sciencedirect.com/science/article/pii/S0306460326001875 2. Short-term HRV dynamics track suicide risk changes in depressive inpatients: A retrospective one-week longitudinal study PUBLICATION: Journal of Affective Disorders AUTHORS: Yi Wang, Chaohua Huang, Baoyi Zhong, Yang Lu, Hao Yu, Yujie Liu, Lanyang Gao, Bo Xiang, Tingting Wang, Kezhi Liu KEY FINDING: Across 177 depressive inpatients, those with moderate-to-high suicide risk showed faster heart rate and lower heart rate variability at admission. As suicide risk dropped over one week of treatment, heart rate variability recovered in step, independent of changes in depression, anxiety, or sleep. SIGNIFICANCE: This is an association, not proof of causation, but it's a compelling one: the heart rate variability signal tracked suicide risk specifically, not just general symptom improvement. That raises real potential for an objective, adjunctive signal in inpatient risk monitoring. Read the full study: https://www.sciencedirect.com/science/article/abs/pii/S0165032726010852 3. Postural Impacts Based on HRV in Young Adults – A Statistical Analysis PUBLICATION: Procedia Computer Science AUTHORS: Prashant Kumar, Ashis Kumar Das, Suman Halder KEY FINDING: Testing three postures in young adults, researchers found statistically significant differences across nearly every heart rate variability parameter, with approximate entropy the lone exception. Short-term and long-term variability measures stayed strongly correlated regardless of posture. SIGNIFICANCE:
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  AAPB Journal Special Podcast 09.07.2026 50min

  Disclaimer: This episode is for educational and professional development purposes only and does not constitute medical advice. Please consult the comprehensive published research and use your own clinical judgment before making any changes to practice. This week we're breaking format. Instead of our usual roundup across multiple sources, we're spotlighting seven studies published in a single journal, Applied Psychophysiology and Biofeedback, spanning cardiac rehabilitation, meditation, aviation safety, occupational fatigue, workplace stress, traumatic brain injury recovery, and music-based biofeedback. Host Matt Bennett walks through the methodology, findings, and honest limitations of each one. Whether you're a clinician, researcher, coach, or practitioner, this special episode offers a rare, single-journal snapshot of where HRV research is headed right now. RESEARCH HIGHLIGHTS THIS WEEK 1. When Diet and Biofeedback Team Up for Heart Recovery Publication: Applied Psychophysiology and Biofeedback Authors: Valeria Carola, Valeria Gigli, Filippo Cellucci, Marco Coli, Sofia Nicolais, Caterina Piras, Giovanni Melina, Cristina Ottaviani, Giampaolo Nicolais KEY FINDING: This systematic review found that heart rate variability biofeedback may enhance autonomic regulation, ease psychological distress, and in some cases shorten hospital stays for cardiac patients, while Mediterranean-style dietary patterns rich in omega-3 fatty acids showed potential to reduce inflammation and favorably modulate cardiovascular risk markers. SIGNIFICANCE: Evidence supporting these noninvasive approaches in postoperative rehabilitation and established cardiovascular disease remains limited, with considerable heterogeneity across studies. This review offers a structured map of where the evidence stands and where standardized protocols are still needed. Read the full study: https://link.springer.com/article/10.1007/s10484-025-09742-w 2. Does Biofeedback Make Meditation Apps Better at Building Body Awareness? Publication: Applied Psychophysiology and Biofeedback Authors: Konrad Rudnicki, Luna Schepers, Koen Rummens, Glen Joris, Karolien Poels KEY FINDING: In this randomized controlled trial of 105 meditation-naive participants, interoceptive accuracy improved in both the cardiac biofeedback-assisted meditation group and the standard app-based meditation group, but not in non-meditating controls. The accuracy gain was concentrated among participants who reported a positive user experience with their device. SIGNIFICANCE: The benefit of biofeedback-assisted meditation apps may depend as much on user experience design as on the underlying biofeedback mechanism itself, an important consideration for anyone recommending these tools to clients. Read the full study: https://link.springer.com/article/10.1007/s10484-025-09728-8 3. What Happens to Pilots' Hearts When the Guide Lights Go Dark Publication: Applied Psychophysiology and Biofeedback Authors: Chuang Liu, Chenyang Zhang, Wenbing Zhu, Shuaitao Jiao, Yu Zhang, Rongbing Xu, Yaowei Liang KEY FINDING: In simulated flights with sixteen cadet pilots, the absence of Precision Approach Path Indicator lights significantly increased mental workload, confirmed by both instructor ratings and heart rate variability measures including SDNN, CVNNI, minimum heart rate, and SD2 from Poincaré analysis.
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  This Week In HRV - Episode 45 07.07.2026 50min

  DISCLAIMER: This podcast is for educational and informational purposes only and does not constitute medical advice. Please consult a licensed healthcare provider regarding any health concerns or before making changes to your care or practice. This week we're covering an unusually wide range of ground: body weight and exercise recovery, a workplace sleep intervention, autonomic function in youth with cerebral palsy, a clinical breakthrough in reading consciousness after brain injury, an AI model predicting cardiovascular risk in older adults, a behind-the-scenes look at what it takes to run 24-hour HRV monitoring, and a study of professional footballers in Senegal. Seven studies, seven populations, one shared physiological language.  RESEARCH HIGHLIGHTS THIS WEEK 1. Why Body Weight Changes How Your Heart Bounces Back After Exercise PUBLICATION: CureusAUTHORS: Vishwadeepak Rajput, Vishavdeep Kaur, Ankalayya Bobbara KEY FINDING: Comparing 100 normal-weight and 100 overweight young adults before and after the Harvard Step Test, researchers found that the overweight group had lower resting heart rate variability and continued to show reduced RMSSD, SDNN, and HF power in the early minutes after exercise, along with a lower Physical Fitness Index score. SIGNIFICANCE: The gap wasn't just present at baseline — it also appeared in how each group's autonomic system responded over time, suggesting that body composition shapes not only resting vagal tone but also the speed and quality of post-exercise recovery. RMSSD and SDNN stood out as the most reliable markers of this difference. Read the full study: https://www.cureus.com/articles/499608-autonomic-response-to-the-harvard-step-test-in-normal-bmi-and-overweight-young-adults-a-heart-rate-variability-study 2. Can a Workplace Program Actually Improve Your Sleep? PUBLICATION: Journal of Activity, Sedentary and Sleep BehaviorsAUTHORS: Johanna Edvinsson, Svend Erik Mathiassen, David M. Hallman KEY FINDING: Office workers who took part in an individual course plus a team-based workshop on managing flexible work arrangements gained 36 minutes of sleep per night over a year, while a comparison group lost 23 minutes per night. Daytime activity levels and sleep-time heart rate variability didn't shift significantly in either group. SIGNIFICANCE: Sleep duration may be the first, fastest-moving lever when organizations help teams set shared norms around flexible work — even before autonomic markers catch up. It's a useful, measurable early win for occupational health programs. Read the full study: https://link.springer.com/article/10.1186/s44167-026-00107-0 3. More Active Youth With Cerebral Palsy Show Better Heart Rhythms PUBLICATION: Journal of Developmental and Physical DisabilitiesAUTHORS: Sonny Riquelme, María Isabel Cornejo, Rosemery Arenas, Javier Russell-Guzmán, Alexis Espinoza-Salinas, Rafael Lima Kons, Matías Henríquez KEY FINDING: In 18 ambulatory youth with cerebral palsy, those reporting higher physical activity levels showed better cardiorespiratory endurance and sprint performance, along with a lower LF/HF ratio — a marker suggesting more favorable autonomic balance — compared to their less active peers. SIGNIFICANCE: This is exploratory...
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  Can Biofeedback Solve Your Workplace Stress? | Dr. Adrian Low 02.07.2026 33min

  Welcome to the Heart Rate Variability Podcast! In this episode, Matt Bennett interviews Adrian Low about a fascinating paper combining workplace wellbeing with biofeedback and mindfulness techniques. They discuss how these practices contribute to overall health and stress management. Remember, this information is for informational purposes only; please consult your medical provider for personalized advice.
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  This Week In HRV - Episode 44 30.06.2026 1h 17min

  This week's episode spans nine studies — from biofeedback and cognitive performance to chronic parenting stress, leadership in VR, body composition, AI-powered hypertension detection, post-cardiac-procedure monitoring, academic burnout, and the question everyone keeps asking about 5G. Whether you're a practitioner, researcher, or someone tracking your own autonomic health, this episode offers something worth sitting with.RESEARCH HIGHLIGHTS THIS  WEEK 1. Can HRV Biofeedback Sharpen Your Memory? A Systematic Review Weighs InPublication: International Journal of PsychophysiologyAuthors: Fernando Rosendo da Cunha e Silva, Esther P.F. Wöllner, Carlos Eduardo Norte KEY FINDING:Across ten studies, HRV biofeedback consistently increased HRV — but its effects on working memory were mixed. Clinical populations, particularly veterans with PTSD, showed meaningful cognitive improvements. Healthy young adults and older adults showed less consistent gains. Significance:HRV biofeedback reliably shifts autonomic function, but cognitive benefits appear context-dependent. Who you're training matters as much as how you're training. Read full study: https://www.sciencedirect.com/science/article/pii/S0167876026000644 2. Low HRV Predicts Worse Outcomes in Somatic Symptom Disorder — 12 Months Out Publication: Journal of Psychosomatic ResearchAuthors: Paul Hüsing, Wei-Lieh Huang, Kerstin Maehder, Franz Pauls, Yvonne Nestoriuc, Bernd Löwe, Kristina Blankenburg, Sophie Schmitz, Stefanie Hahn, Anne Toussaint KEY FINDING:In 148 patients with Somatic Symptom Disorder, those with a low HRV pattern showed consistently higher somatic symptom severity, depression, and psychological distress — and these differences held stable across a full 12 months with no significant change over time. Significance:HRV pattern classification at baseline may identify which SSD patients are at risk for persistent, long-term symptom burden — offering a physiological lens for a condition that is otherwise difficult to stratify. Read full study: https://www.sciencedirect.com/science/article/pii/S0022399926003855 3. Chronic Parenting Stress Shows Up in HRV — and in the Blood Publication: Stress and HealthAuthors: Marija Ljubičić, Ivana Kolčić KEY FINDING:Parents of children with chronic conditions — particularly autism spectrum disorder — showed reduced HRV and elevated Advanced Glycation End Products (AGEs), a marker of oxidative stress. A child's challenging behaviour and parental stress were the key drivers of these physiological changes. Significance:Chronic caregiving stress doesn't just feel hard — it produces measurable autonomic and oxidative consequences. HRV monitoring in caregiving populations may be an underutilized health tool. Read full study: https://onlinelibrary.wiley.com/doi/10.1002/smi.70185 4. Reading the Room in VR: How Physiological Signals Could Help Leaders Facilitate Better Publication: Frontiers in Computer ScienceAuthors: Chenghao Gu, Jiadong Chen, Tianyuan Y...
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  This Week In HRV - Episode 43 23.06.2026 1h 7min

  This week on This Week in Heart Rate Variability, we explore four studies that collectively challenge us to think more deeply about what autonomic function tells us — and what it doesn't tell us on its own. From addiction treatment to heart failure, adolescent fitness to chronic pain, this episode traces the threads connecting heart rate variability to some of the most pressing questions in clinical and population health. Whether you're a practitioner, researcher, or someone tracking your own autonomic health, there's something in this episode that will change how you think about what your nervous system is doing.RESEARCH HIGHLIGHTS THIS WEEK1. HRV and the Recovery Gap: When Physiology and Mental Health Walk Different Paths Publication: Frontiers in Psychiatry Authors: Wendy Insalaco, Charlotte Clapham, Brett Gelino, Jami Mayo Barney, Brianna Billings, Jennifer D. Ellis, J. Gregory Hobelmann, Andrew S. Huhn, Vadim Zipunnikov, Jill A. RabinowitzKEY FINDING:In fifty-nine individuals undergoing residential substance use disorder treatment, resting heart rate, heart rate variability, and self-reported stress, anxiety, and depression all tended to improve over the first month. However, at the individual level, physiological improvement and mental health improvement did not reliably co-occur — fewer than half of participants with improving physiological metrics showed concurrent improvements across all mental health domains. Significance:This finding challenges the assumption that wearable physiological metrics and subjective mental health assessments are capturing the same recovery signal. For clinicians and treatment providers, it suggests that both dimensions of recovery must be monitored independently, and that physiological improvement should not be interpreted as a proxy for psychological wellbeing in early recovery.→ Read full study: https://doi.org/10.3389/fpsyt.2026.1755153 2. The Clock is Broken: Circadian HRV Disruption in Heart FailurePublication: BiomedicinesAuthors:Natalia Buitrago-Ricaurte, Andre J. Riveros, Rafael González Niño, Liliana Otero, Juan David Meléndez, Alain Riveros-RiveraKey Finding:In eighty-six patients with cardiac remodeling compared to eighty-six controls, twenty-four-hour autonomic monitoring with Cosinor modeling revealed not only reduced overall heart rate variability but blunted circadian amplitude and phase shifts in autonomic modulation — a loss of the normal day-night rhythm of sympathovagal balance. Significance:This study highlights that the timing and rhythm of autonomic dysfunction may matter as much as its average level. Circadian HRV profiling may provide diagnostic and prognostic information in heart failure patients beyond what short-term or snapshot measurements offer, and opens therapeutic avenues targeting circadian autonomic restoration.→ Read full study: https://doi.org/10.3390/biomedicines14051054 3. Moving More Matters Most When It's Hardest: Physical Activity and HRV in Young MenPublication: Physical Activity and HealthAuthors: Jaakko Tornberg, Tiina Ikäheimo, Kaisu Kaikkonen, Riitta Pyky, Marjukka Nurkkala, Arto Hautala, Timo Jämsä, Raija Korpelainen Key Finding:Across three thousand three hundred and eighty-nine adolescent men, higher physical activity was significantly associated with higher RMSSD across all body mass...