By Faye Martins
What is heart rate variability (HRV)? How does it relate to our health and our Yoga practice, especially Yoga Nidra? First, let’s define a few catch phrases to make this relationship easier to understand.
• Heart rate – the number of times the heart beats within a given time, usually a minute.
• Heart rate variability – a measurement of the intervals of time between individual heart beats
• Blood pressure – the pressure of the blood against the inner walls of blood vessels, especially the arteries
• Autonomic nervous system – the system that controls involuntary actions like breathing, heart rate, and digestion
• Yoga Nidra – Yogic sleep; deeply relaxed state of the body and mind in which brain waves slow down and consciousness expands
Over the past two decades, scientists have confirmed the importance of the autonomic nervous system in physical, emotional, and mental health. One of the markers they use to measure its effect on the body is heart rate variability. Although related to heart rate and blood pressure, HRV actually measures the fluctuations, or intervals, from one heartbeat to the next.
What affects heart rate variability?
Even the healthiest hearts don’t beat with the regularity of Big Ben. They are in a rapid state of flux, influenced by physiological and emotional factors. When a deer leaps in front of our car, our heart beat speeds up and our body pumps out adrenaline. We slam on the brakes, respond to the crisis, and our body gradually returns to normal.