Heart Rate

What are Resting Heart Rate and Heart Rate Variability?

Monitoring heart rate through wearable health-tracking devices has become a key aspect of managing overall health and fitness. Resting heart rate (RHR) and heart rate variability (HRV) are two crucial metrics that provide insights into cardiovascular health and fitness levels. Resting heart rate is the number of heartbeats per minute when a person is at rest. It is an indicator of cardiovascular efficiency and overall fitness. A lower RHR typically signifies better cardiovascular fitness and more efficient heart function, while a higher RHR can indicate poor cardiovascular health or higher levels of stress and fatigue.

Heart rate variability, on the other hand, measures the variation in time between each heartbeat. HRV reflects the autonomic nervous system's regulation of the heart, indicating how well the body can adapt to stress, recovery, and overall resilience. Higher HRV is generally associated with better cardiovascular fitness, stress resilience, and overall health, while lower HRV can indicate stress, fatigue, or underlying health issues. {{{https://www.health.harvard.edu/blog/heart-rate-variability-new-way-track-well-2017112212789}}} For resting heart rate, a typical range for adults is 60 to 100 beats per minute (bpm) {{{https://www.mayoclinic.org/healthy-lifestyle/fitness/expert-answers/heart-rate/faq-20057979#:~:text=A%20normal%20resting%20heart%20rate%20for%20adults%20ranges%20from%2060,to%2040%20beats%20per%20minute.}}}, with athletes or highly fit individuals often having a resting heart rate as low as 40 bpm. Various factors, including age, fitness level, medication, and temperature, can influence resting heart rate {{{https://www.health.harvard.edu/heart-health/is-a-low-heart-rate-worrisome}}}. For heart rate variability, values can vary widely among individuals. Generally, higher HRV indicates better fitness and stress resilience, with values above 100 milliseconds (ms) often seen in highly fit individuals, while lower HRV is common under stress or chronic health conditions.

Improving both RHR and HRV involves lifestyle changes that enhance cardiovascular fitness and stress management. Regular exercise, such as running, swimming, or cycling, can improve heart function and lower RHR. A balanced diet rich in fruits, vegetables, lean proteins, and whole grains also supports cardiovascular health. Stress management techniques like yoga, meditation, or deep breathing exercises can enhance HRV, while adequate sleep is crucial for supporting cardiovascular health and autonomic function. Limiting intake of stimulants like caffeine and nicotine can also help manage both RHR and HRV. {{{Grässler B, Thielmann B, Böckelmann I, Hökelmann A. Effects of Different Training Interventions on Heart Rate Variability and Cardiovascular Health and Risk Factors in Young and Middle-Aged Adults: A Systematic Review. Front Physiol. 2021;12:657274. Published 2021 Apr 23. doi:10.3389/fphys.2021.657274}}}

A resting heart rate consistently above 100 bpm (tachycardia) or below 60 bpm (bradycardia) in non-athletes can signal potential health issues requiring medical attention. Elevated RHR increases the risk of heart disease and other cardiovascular conditions, while abnormally low RHR can indicate problems such as bradycardia. Low heart rate variability is associated with increased stress, fatigue, and a higher risk of cardiovascular diseases, whereas extremely high HRV, although rare, can sometimes indicate overtraining in athletes or other health issues. {{{https://www.mayoclinic.org/healthy-lifestyle/fitness/expert-answers/heart-rate/faq-20057979#:~:text=Consult%20your%20doctor%20if%20your,dizziness%20or%20shortness%20of%20breath.}}}

Wearable health trackers like Fitbit, Apple Watch, and Garmin devices provide advanced features for monitoring heart rate and HRV. These devices offer real-time data and insights into resting heart rate, heart rate variability, and exercise heart rate, helping users identify patterns, monitor their cardiovascular health, and make informed decisions to improve their fitness and well-being.

Where can I learn more?

  1. Hospital for Special Surgery - How to Use Heart Rate Variability Data in Your Training
  2. European Society of Cardiology - Guidelines Heart Rate Variability
  3. American College of Cardiology - The Heart Responds Differently to Exercise in Men vs. Women