Heart Rate Variability (HRV)

The Heart Rate Variability (HRV) is a measure of the variation in time between each heart beat, otherwise known as the R–R interval or the inter-beat interval. The time between each heartbeat is not consistent, it varies with every beat. Measuring how much it varies can be used to access fitness and recovery in athletes. The Polar Fitness Test uses HRV in its measurement.

Heart Rate Measurement


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