• Fitness & Health
• Sport & Exercise Science
• Physical Education
• Strength & Conditioning
• Sports Medicine
• Sport Management
• Dance

What is the difference between heart rate and HRV?

This is an excerpt from Heart Rate Variability by Sylvain Laborde,Marco Altini,Emma Mosley,Dan Plews.

At first glance, heart rate and HRV might seem to convey similar information: Both are derived from the heart’s activity. However, whereas heart rate provides a snapshot of beats per minute, HRV provides further insights, offering a window on the body’s physiological resilience and adaptability (Buchheit, 2014; Laborde et al., 2017).

Heart rate and HRV differ in the way in which they are calculated. Whereas heart rate reflects the average number of heartbeats per minute, HRV is calculated by measuring the precise time interval in milliseconds between each heartbeat (the RR interval) and then analyzing the variability in these intervals over time. This difference highlights the fact that whereas heart rate provides an average of heartbeats per minute, HRV offers a detailed view of beat-to-beat fluctuations, capturing dynamic changes in the activity of the autonomic nervous system (see figure 1.3).

Let’s take a heart rate of 60 beats per minute (bpm) as an example. It might seem logical to assume that each heartbeat would come exactly 1 s apart. But if that were true, it would be a sign that something is seriously wrong. In fact, as pointed out by Shaffer et al. (2014), a healthy heart does not behave like a metronome. Instead, the time between beats usually varies: One beat might take 952 ms, the next 1,032 ms, followed by 984 ms, followed by 1,023 ms, and so on. HRV is calculated by analyzing these small variations in the time between each heartbeat—your heart’s secret code.

More Excerpts From Heart Rate Variability

---