Welcome to the WHOOP Research Series, where we breakdown into the extensive, scientific research conducted by the WHOOP Performance Science team. On this week’s episode, WHOOP Global Head of Human Performance, Principal Scientist, Dr. Kristen Holmes sits down with WHOOP Senior Research Scientist Dr. Greg Grosicki to unpack the latest WHOOP Research Study on Heart Rate Variability Coefficient of Variation or HRV-CV. Using data from 21,000+ WHOOP members and 2 million nights of sleep, Dr. Holmes and Dr. Grosicki reveal why day-to-day stability in your HRV may matter more than the number itself. HRV-CV proves to outperform traditional metrics in detecting the real impact of alcohol, sleep consistency, and metabolic health, making it a great measure of healthspan. By looking deeper into the study, Dr. Holmes and Dr. Grosicki explains how HRV-CV can help you program your training smarter, improve your healthspan and build autonomic resilience. This episode unpacks how measuring HRV-CV isn’t just about performance, but risk stratification and understanding your physiology over-time, not just day-to-day.

(01:11) Intro To The Study: Why Is HRV-CV Important?

(04:09) HRV-CV and Risk Stratification

(08:28) Definition of HRV-CV

(11:40) What HRV-CV Indicates in Athlete Recovery

(14:26) Breaking Down The WHOOP Study

(17:13) HRV-CV Trends in Shift Workers

(21:21) Why Is HRV-CV an Important Biomarker?

(25:18) HRV-CV Trends in Individuals on GLP-1 Medications

(26:29) The Weather vs. The Climate: HRV vs. HRV-CV

(33:41) The Results: Breaking Down the Data

(36:37) How HRV-CV Responds to Certain Behaviors

(39:38) Trends Between HRV-CV Between Age, Biological Sex, and Body Mass Index