Heart Rate Variability

Understand heart rate variability and its role in athletic performance.

Heart rate variability (HRV) is a valuable tool used to assess cardiac function, evaluate mental and emotional well-being, and—when used by athletes and coaches—optimize training based on each athlete’s unique data.

Written by a world-renowned author team, Heart Rate Variability: Science and Strategies for Peak Performance introduces the fundamentals of HRV and provides practical guidance on how to measure and interpret HRV data, train smarter, prevent injuries, manage stress, and improve overall health.

With coverage spanning everything from factors affecting HRV to ways to enhance training, this book will help coaches, trainers, and athletes appreciate just how much performance can be influenced by this physiological measurement. Explanations of data collection, interpretation, and application to training are included, making it easy to take action based on what you learn. Physical monitoring isn’t the only thing HRV data can be used for; the authors also describe how mental training can be used jointly with HRV measurements to enhance performance and manage psychological stress.

Learn from the experts and then incorporate data into your training with a 30-day challenge centered around consistently measuring, interpreting, and improving your HRV. What is your heart telling you?

Earn continuing education credits/units! A continuing education exam that uses this book is also available. It may be purchased separately or as part of a package that includes both the book and exam.

Audience

Advanced and elite athletes, sport enthusiasts, coaches, and personal trainers who have an interest in the potential for HRV training to improve performance.

Introduction. Why This Book? Starting the Journey With HRV
What Are Our Stories With HRV in Numbers?
Why Is HRV Important?
How Can This Book Help You?
Final Thoughts to Kick-Start Your HRV Reading Journey

Part I. The Science Behind HRV
Chapter 1. Physiology Foundations
Understanding the Physiological Foundations of HRV
What Is the Difference Between Heart Rate and HRV?
The Physiology of HRV
HRV Indexes
Vagally Mediated HRV
Cardiac Vagal Activity and Vagal Tank Theory
The Implications of Vagal Tank Theory
Myths About HRV: Separating Fact From Fiction When Interpreting HRV
Interpreting Indexes of Non–Vagally Mediated HRV
The Role of Context in HRV Interpretation

Chapter 2. Global Factors That Influence HRV
Population-Level Analyses: Understanding Individual Differences in Genetics, Sex, Age, Ethnicity, Physical Activity, and Body Mass Index
Individual-Level Analyses: How Data Changes Over Time in Relation to Stressors
Environmental Stressors

Chapter 3. Impact of Sleep, Nutrition, and Hydration on HRV
Sleep and HRV
Nutrition and HRV
Hydration and HRV

Part II. Measurement and Interpretation of HRV
Chapter 4. HRV Monitoring and Tracking Tools
Common Methods and Devices for Measuring HRV
HRV Versus Pulse Rate Variability
Know Your Application: ECG Versus Photoplethysmography Versus Ballistocardiography
Protocols and Best Practices: How to Accurately Measure HRV
When to Measure HRV
Body Position: Should You Measure Lying Down, Sitting, or Standing? 
Frequency of HRV Measurements
Duration of HRV Measurements
Chest Straps, Wristbands, Finger Sensors, and Phones: What Can You Use? 
The Impact of Breathing on Data Collection
Artifacts in HRV Data: Movement, Ectopic Beats, and Arrhythmias
Learn to Ask the Right Questions

Chapter 5. Interpreting HRV Data
Acute Response to Training Stress and HRV
Understanding Meaningful Changes in HRV Indexes: The Normal Range
Identifying Changes in HRV and What They Mean for Your Health and Fitness
Heart Rate and HRV Saturation
Physiological Adaptations to Training

Part III. Applications of HRV Monitoring
Chapter 6. Using HRV to Guide Individualized Training
Autonomic Regulation and Trainability: What HRV Can Tell Us
The Beginnings of HRV-Guided Training
State of the Art in HRV-Guided Training: The Big(ger) Picture and Baseline Deviations
The Future of Individualized Training: A Combined Approach?
Expected Outcomes of HRV-Guided Training
Beyond Baseline Assessments

Chapter 7. Applying HRV in Team Settings
Devices for Monitoring HRV in Team Sports
The Basics of HRV in Team Sports
Challenges of Monitoring HRV in Team Sports

Chapter 8. Injury Prevention
Using HRV Monitoring to Detect Early Signs of Overtraining and Injury
HRV-Guided Training for Injury Prevention
HRV-Guided Training for Injury Rehabilitation
HRV for the Management of Brain Injuries and Concussions

Chapter 9. Disease Prevention and Management
The Role of Autonomic Function in Health and Disease
HRV and Fundamental Health Mechanisms
The Role of HRV in Disease Prevention and Management
Improving Health Outcomes With HRV Monitoring

Part IV. The Brain’s Impact on HRV
Chapter 10. HRV and Cognitive Function
HRV, Mental Performance, and Function
Brain Structure and HRV
The Prefrontal Cortex, Executive Function, and HRV
Measuring HRV for Cognitive Performance
Physical Activity and HRV
HRV and Mental Fatigue
Collecting HRV Data to Manage Mental Fatigue and Improve Cognitive Functioning
Strategies to Overcome Mental Fatigue and Improve Executive Performance

Chapter 11. Managing Psychological Stress
Understanding Psychological Stress
Strategies for Using HRV to Manage Psychological Stress
Burnout and HRV
Challenges and Limitations of Monitoring HRV to Manage Psychological Stress

Chapter 12. HRV and Mental Training
Psychological Skills: The Foundations
Breathing Techniques
Mind–Body Relaxation
The Low HRV Autopilot
Inspirational Techniques
Self-Reflection
Connection Matters: The Power of Social Support for HRV

Part V. Maximizing HRV Data for Athletic Performance
Chapter 13. Your Daily HRV Routine
The Ease of Capturing HRV Data
What Could Your HRV Day Look Like?
HRV Analysis Before and After Exercise
What About Continuous HRV Monitoring?

Chapter 14. A 30-Day HRV Training Plan
Why Complete an HRV Challenge?
Your HRV-Supporting Morning Routine
Your HRV-Supporting Evening Routine
Building Blocks for HRV Awareness and Improvement
The 30-Day HRV Challenge
What to Do After the 30-Day HRV Challenge

Epilogue. Your HRV Journey Is Just Starting
Summary of Key Takeaways
Personal Growth and Continuous Learning
Start Simple and Build a Solid Foundation
HRV for Athletic Training and Performance
Interpreting Data and Making Training Decisions
Overview of HRV Applications Across Sports
Sharing Your HRV Journey

Sylvain Laborde, PhD, is a renowned senior lecturer in sport psychology at the prestigious German Sport University Cologne, Europe’s largest sports institution, where he founded the HRV–Performance Psychophysiology Lab. He holds two doctorates (in sport science and in psychology) and has dedicated the past 15 years to exploring the intricacies of HRV and the vagus nerve in athletes.

Regarded as a global authority on HRV and author of more than 150 peer-reviewed scientific research papers, Dr. Laborde has captivated audiences with his compelling insights and innovative ideas. As an award-winning speaker, he has shared his expertise in five languages (French, English, German, Spanish, and Italian) in numerous keynote addresses, talks, and workshops across over 20 countries, reaching Olympic committees, national coaches, and elite athletes alike. Dr. Laborde’s groundbreaking vagal tank theory, elaborated with his coauthor Emma Mosley, translates complex research findings into practical applications for everyday life. The applications of his work focus on noninvasive vagus nerve stimulation to improve performance and self-regulation abilities of athletes, using techniques such as slow-paced breathing and the diving reflex. With this approach, he has empowered countless individuals to harness the power of HRV for improved performance and well-being.

In this book, Dr. Laborde embarks on a new mission to provide athletes, coaches, and performance seekers with the first comprehensive guide to monitoring and enhancing HRV. This groundbreaking book is a testament to his relentless pursuit of knowledge and his unwavering commitment to improving lives through the science of performance optimization.

Marco Altini, PhD, MSc, is a scientist and developer mainly working at the intersection of health, technology, and performance. He holds a doctorate (cum laude) in data science, a master’s degree (cum laude) in computer science engineering, and a master’s degree (cum laude) in human movement sciences, with a specialization in high-performance coaching.

Dr. Altini is the founder of HRV4Training, a platform he developed in 2012 that is today trusted by more than 150,000 users, including Olympic medalists and professional teams. HRV4Training uses advanced signal processing and data analytics to measure HRV and quantify stress, helping athletes of all levels to better balance training and lifestyle stressors to improve performance.

Dr. Altini’s blog entries and articles on various online platforms (e.g., Medium, Substack) have reached more than one million readers. He has also published more than 50 scientific papers and patents at the intersection of technology, physiology, health, and performance. He developed numerous software solutions to track and improve heart rate variability, both independently (HRV4Training, HRV4Biofeedback) and for other organizations (Oura, Strava).

Dr. Altini is a guest lecturer at Vrije Universiteit Amsterdam and an advisor to various companies working on the use of heart rate variability for applications targeting mental and physical health. He has been a guest in countless podcasts and interviews as a leading expert and trusted authority when it comes to the measurement and use of heart rate variability. As a recreational athlete, he loves to practice what he preaches, a journey that recently brought him to break the 3-hour barrier in the marathon.

Emma Mosley, PhD, is a senior lecturer in sport and exercise psychology in the faculty of allied health and exercise sciences  at Bournemouth University. Dr. Mosley holds the Accredited Sport and Exercise Scientist certification from the Chartered Association of Sport and Exercise Sciences (CASES) and the Chartered Scientist credential from the Science Council. She has a doctorate in HRV and performance under pressure and has studied HRV for over a decade.

She is a leading researcher within HRV and, together with Sylvain Laborde, she has paved the way for robust HRV research within psychophysiology as well as sport and exercise psychology. Dr. Mosley has published milestone papers within this field, including a highly cited methodological paper on vagal tank theory written with Sylvain Laborde, and a systematic review surrounding the use of HRV in sport and exercise psychology. Her research has evolved to explore the applied domain, and she has published multiple papers examining HRV interventions in elite athletic populations.

Dr. Mosley has worked in elite sport (e.g., Formula 3) and with the International Biathlon Union on a funded HRV project. She has also worked within the corporate sector, delivering HRV-informed breathing sessions to high-performing teams. She is deeply passionate about making HRV accessible and understandable for all.

Dan Plews, PhD, is an accomplished applied sport scientist, researcher, and coach with an impressive record of success. He has worked closely with athletes who have won more than 30 world and Olympic titles in the sports of rowing, kayaking, and triathlon.

Dr. Plews is a recognized expert in the field of HRV, having completed his doctorate in the area of applied HRV. His research focused on implementing and validating methods for the application of HRV to track training adaptation in elite athletes. His work has been published in over 60 peer-reviewed articles, with over 3,500 citations.

Throughout his career, Dr. Plews has held several important roles, such as head of physical performance at Emirates Team New Zealand during the 2021 America’s Cup–winning campaign and lead physiologist for Rowing New Zealand during both the London and Rio Olympic Games. He is currently leading performance physiology for Women’s Canoe Racing New Zealand, where he continues to implement his research and expertise to support athletes in achieving their goals.

Dr. Plews’ passion for triathlons is evident as he continues to excel as both an athlete and a coach. He coached Chelsea Sodaro to victory in the 2022 Ironman World Championships and broke the amateur course record at the Ironman World Championships in Kona, Hawaii, in 2018, finishing in 8 hours and 24 minutes. In October 2023, he was the overall winner and set the fastest finishing time for an age-group athlete in the full-distance Ironman California triathlon, completing the course in 7:56:56. Dr. Plews’ achievements and dedication to sport science and exercise physiology are a true inspiration to athletes and sports enthusiasts around the world.