Heart Rate Variability
Our body is a finely integrated operating system consisting of the collective workings of many systems within.
These systems do not work independently but inter-dependently of one another.
One such system is our Autonomic Nervous system (ANS) that regulates body systems on an unconscious level. Your blood pressure, blood sugar levels, adrenaline levels, digestion, heart rate and much more gets regulated without our conscious awareness during waking and sleeping times.
Basic Heart Rate Variability (HRV) measurements are the changes we see in time between successive heartbeats, inter-beat-intervals. (see below diagram)
With general wellness your mean heart rate has become an indicator of fitness and health predictor. With Heart Rate Variability (HRV) we have learned to look at fluctuations of the heartbeats that becomes evident when we respond to internal and external events on a moment to moment basis.
HRV measurements has shown to be indicative of the direct link to our Autonomic Nervous System (ANS), giving us insights into our nervous systems response to stress and recovering ability. Our ANS consists of two main branches:
Our body is constantly adjusting to the environment by either “speeding up” or “slowing down” in order to maintain balance and homeostasis. When our autonomic nervous system gets “stuck” and either just speeds up and not slowing down when needed it has detrimental effect on our health.
FIGURE 1. A typical HRVB screen showing the transition from normal breathing to 7 breaths per minute breathing.
In the Psychophysiological research field HRV originally focused on autonomic balance, advances in the medical field focused on HRV as the indicator of adaptability and Baroreflex sensitivity. Other work looked at the impact HRV has on vagus nerve activity in various disorders like asthma and pain management and anxiety disorders.
Many research projects are underway to look at the effect of the heart on the brain / CNS. There are evidence that the heart has stronger impact on the brain than vice versa.
The procedure consists of feeding back beat by beat heart rate data during slow breathing manoeuvre’s such that the participant tries to maximize RSA, create a sine-wave-like curve of peaks and valleys, and match RSA to heart rate patterns. RSA is the heart pattern that occurs when heart rate increases during inhalation and decreases during exhalation. Thus as can be seen in Figure 1, the participant uses feedback or a breath pacing device to produce the characteristic maximized RSA. Breathing at your resonant breathing frequency increases HRV.
HRV training is an evidence-based training modality (Biofeedback) used to increase the active control over the body’s response to stress. It creates the bridge between the heart and the Brain / nervous system. Bringing into consciousness the processes that gets influenced by the ANS.
Biofeedback training allows accurate feedback mirroring what your heart is communicating to the rest of your nervous system, in time learning to gain better control over how your body reacts to the stress stimuli and building on your resilience to such stress stimuli. Combining HRV with other modalities like Psychotherapy, CBT and stress management strategies your client enables themselves to better self-regulate in day to day situations. HRV Biofeedback training teaches clients can realize multiple benefits including:
Enhanced cardiac health
Reduction in anxiety and performance anxiety symptoms
Reduced muscle tension
Improvement in general energy and mood
Clearer cognitive abilities
Calmness and faster reaction times
Improved hormone balance
Improved immune system activity
Improve on recovery rate after intense physical training
Gevirtz (2013) recently reviewed all of the available literature on the outcomes of HRVB. He looked at the following application categories: asthma, COPD, IBS, cyclic vomiting, recurrent abdominal pain, fibromyalgia, cardiac rehabilitation, hypertension, chronic muscle pain, and pregnancy induced hypertension, depression, anxiety, PTSD, insomnia, and performance. While few areas have extensive support by way of controlled studies, the overall picture seems to be very promising for this intervention. As can be seen, the applications are quite varied. We have begun to explore what physiological and/or psychological mechanisms might be contributing to these positive outcomes.