Heart Rate Variability and
Heart Coherence Breathing
A healthy heart has a natural variation, from minute to minute, beat to beat – even when you are sitting at rest. A change equivalent to 30 beats per minute over just a few seconds is not uncommon. This phenomenon is known as Heart Rate Variability (HRV). It’s a sign of health – in fact the greater the variability the better.
Heart rate (HR) is intimately tied to the bodily expression of emotions. You can probably think of times when your heart raced with excitement, or "missed a beat" following a shock.
However, patterns within the variability are much more significant than the simple rate. In states of stress, anxiety, anger and sadness the variation tends to be disordered and chaotic. In positive emotional states such as love and gratitude, the variation tends to be ordered and rhythmic. This state of rhythmic variation is known as Heart Coherence, and is a highly efficient and healthy mode of operating.
The screen shots above show: (Left) Heart Rate Variability graphs for two contrasting states of mind. The horizontal time scale is 4 minutes on each graph. (Right) Biofeedback computer screen showing chest and abdominal breathing (blue tracings) and moment-to-moment change in heart rate (red tracing). When the breathing and heart rate tracings become perfectly synchronized, maximal heart coherence is in effect.
Biology of Heart Rate Coherence
The brain has a number of channels of communication with the heart, notably the Autonomic Nervous System (ANS) and the hormone system. The ANS has two branches, the sympathetic and the parasympathetic, which work on the heart like an accelerator and brake respectively. When the heart is in a state of coherence, HRV synchronizes with the breath – a phenomenon known as Respiratory Sinus Arrhythmia (RSA). Heart Coherence is much more than a state of relaxation. It represents a dynamic balance within the ANS. On the in-breath, the sympathetic branch (accelerator) is active, and heart rate increases, while on the out-breath, the parasympathetic branch (brake) is active, and the heart slows.
It is less well known that heart-brain communication is actually two-way. The heart has its own "brain" – a group of at least forty thousand neurons, some of which project back to the brain.
The heart can drive many other oscillatory systems within the body, including brainwaves (EEG), craniosacral rhythms and blood pressure rhythms – hence the use of the term ‘coherence’. As mentioned it is a highly efficient mode of functioning with many beneficial effects:
- faster reaction times
- improved hormone balance – e.g. levels of the "stress hormone" cortisol decrease, while levels of DHEA (the "youth hormone") increase
- improved cardiac health
- improved immune system activity
- emotional balance: as mentioned, the heart is able to send signals back to the brain. Healthy heart rhythms have a beneficial effect on the emotional brain. Thus HRC facilitates positive emotion and weakens negative emotion
- improved thinking: cognitive performance can be faster and more accurate. Research subjects report thinking more clearly.
Heart Rate Variability Biofeedback Training
Heart Coherence is very much a natural state of functioning. That doesn’t mean it should be present all the time, but ideally a few quiet periods of heart coherent breathing at various "breaks" in the day will be restorative and balancing.
The ability to consciously engender the state of coherence is desirable because it creates a sense of control and strengthens the body’ self-regulatory processes to increase homeostasis.
In Heart Rate Variability (HRV) biofeedback training, computer analysis of heart rate and respiratory rate information generates a measure of the level of coherence. This information is fed back to the trainee on an on-going basis, so that the trainee can learn how his efforts are affecting his coherence. With the proper HRV biofeedback training, most individuals can readily learn to engage in slow, effortless diaphragmic breathing at a specific rate that will synchronize breathing with their natural heart rhythms and put them into a state of heart coherence. Once the technique is learned and the specific breath rate is internalized, the individual no longer needs the support of biofeedback instruments to be able to effectively put themselves into a state of heart coherence at will and to use the technique to bring balance to their autonomic nervous system and make self-regulation a reality.
Trainee using HeartMath Freeze Framer
HRV Biofeedback program.
HRV biofeedback training can form a useful component of therapy for:
- Anxiety and Panic
- Irritable Bowel Disease
- Stress-related symptoms including: insomnia, fatigue, aches and pains, high blood pressure and pre-menstrual symptoms.
In addition HRV biofeedback training can help with several organic conditions including: asthma, fibromyalgia, chronic fatigue, diabetes and cardiac arrhythmias.
Heart Coherence breathing and associated increase in heart rate variability can be an important component of a cardiac rehabilitation program following heart attack.