How Stressed Are You? – Assess Your Stress Level with Heart Rate Variability
BY: DR. JULIE MILLER
Heart rate variability (HRV) is a non-invasive technology that can be used to provide important information about overall health and fitness. It was initially thought that the heart rate was monotonously regular but we now know that the rhythm of the healthy heart displays small variations between each beat. As a marker of the body’s resilience, HRV reflects the ability to adapt effectively to stress and environmental demands. Although too much variation can be detrimental, too little variation can also be problematic and is associated with poor health and chronic illness.
The variability in heart rhythm is a result of the push and pull action of the autonomic nervous system (ANS). The ANS is part of our peripheral nervous system and governs the processes in our body that occur without conscious awareness such as heart rate, breathing, digestion, and blood flow. The ANS can then be further divided into 2 main branches:
- Sympathetic Nervous System: the “fight or flight” division that is activated during times of stress
- Parasympathetic Nervous System: the “rest and digest” division that facilitates sleep and optimal digestion
The enteric nervous system, an extensive network of nerves surrounding the digestive tract, is often considered to be the third branch of the ANS. The disordered functioning of the enteric nervous system due to food intolerances, infections, toxicity, and psychological stressors, is a major cause of Irritable Bowel Syndrome.
In addition to indicating the body’s overall ability to handle stress, HRV also tells us the balance between the sympathetic and parasympathetic divisions of the ANS. The function of the sympathetic nervous system is to prepare our body for a potentially life threatening situation and to shut off when the threat subsides. However, in today’s hectic society, it generally isnT the “life or death” situations that set off the fight or flight response, but rather numerous smaller stressors that result in nearly continuous sympathetic stimulation. Consequently, many people become “stuck” in sympathetic dominance which results in symptoms such as: chronic tension, agitation, anxiety, insomnia, high blood pressure, heart palpitations, and sub-optimal digestion. Without proper support, including ideal nutrition and effective stress management, the body will eventually burn out and can become parasympathetic dominant. Individuals with over-activity of the parasympathetic nervous system often experience extreme fatigue, lethargy, spasms in the digestive tract or lungs, and depression.
HRV is an extremely valuable tool in that the ANS influences many processes in the body and facilitating sympathetic and parasympathetic balance can have a dramatic impact on overall health and well-being. However, in order to achieve this balance it also necessary to identify stressors, both physical (eg infections, food intolerances, blood sugar imbalance, toxicity, poor nutrition) and psychological (eg work demands, relationship disharmony, negative beliefs/self-talk) and address them accordingly.