Leading HRV Expert On The Data Your Wearable Is Making Up | Marco Altini

Dr. Marco Altini joins Klaudia and Don for the deepest heart rate variability conversation the show has done yet.Marco holds a PhD cum laude in applied machine learning, an M.Sc. in human movement sciences and high-performance coaching, has published more than 50 papers and patents at the intersection of physiology and technology, co-founded HRV4Training, advises Oura, guest-lectures at VU Amsterdam, edits for IEEE Pervasive Computing Magazine, and just released his first book, Heart Rate Variability: Science and Strategies for Peak Performance (Human Kinetics, May 2026).This conversation covers the full arc of HRV, from the foundational science, to how to measure it correctly, to what actually moves the number, to how elite athletes and coaches use it to train smarter, to the surprising links between HRV, the brain, and burnout.A quick note on this episode: shortly after we started recording, Marco had to turn his video off to make sure we could give you the clearest possible audio. He was joining us from Italy, and the connection wasn't cooperating on the video side, but the conversation was too good not to bring to you, so we prioritized the story over the picture. Thanks for understanding!In this episode:Marco's path from machine learning to human movement science to HRVThe most dangerous hype in wearables and biometrics right nowThe biggest HRV myths even serious athletes and coaches still believeMarco's validity findings on Garmin's Health Snapshot featureThe minimum viable daily HRV measurement routineVagally mediated HRV and the Vagal Tank Theory, explained simplyChest strap vs. wristband vs. finger sensor vs. phone camera — an honest accuracy rankingWhether continuous HRV monitoring is useful or just noiseWhat the newest habit-and-HRV research actually showsMetabolic flexibility, fueling, and how it shows up in endurance athletes' dataHow altitude, heat, and travel affect HRV — and what to do about itWhat HRV-guided training looks like day-to-dayTapering, race-day HRV, and team-sport applicationsHRV, cognitive function, mental fatigue, and burnoutThe Normal Range concept from HRV4Training ProWhere wearable and HRV monitoring is headed in the next 5 yearsThe 30-Day HRV Challenge from Marco's new bookGuest: Dr. Marco Altini — Co-founder, HRV4Training | Advisor, Oura | Guest Lecturer, VU Amsterdam | Editor, IEEE Pervasive Computing Magazine | Co-Author, Heart Rate Variability: Science and Strategies for Peak Performance (Human Kinetics, 2026)Hosts: Klaudia Balogh (Longevity Journalist, longevityjournalist.com) & Don Moxley (Sports Scientist, trainrecoverwin.com)🔗 Marco's Substack: hrv4training.substack.com📖 The book is available now through Human Kinetics and Amazon🎧 New episodes of the 90% Healthy Podcast drop weekly. Subscribe, comment your HRV questions, and let us know who needs to hear this one.