How your brain, muscles, heart, and circulatory system communicate in dealing with stress - and why techniques for creating a 'relaxation response' are the cornerstone of mind/body medicine in heart disease.
As background for this discussion, let's begin by noting three key principles about your cardiovascular system.
Three Key Principles of the Cardiovascular System
The first principle is that your heart is a muscle.
Like other muscles of your body, your heart can be in various states of conditioning or fitness, through the proper balance of exercise and rest. As a muscle, your heart feeds on the life-giving nutrients brought to it by blood circulation. If there's not adequate circulation into the heart muscle itself, its life is seriously threatened.
It can't stop functioning to rest or heal, like leg or arm muscles can when they are injured or depleted. When your heart is over-extended and under-nourished, it still desperately seeks to continue pumping. This can lead to the collapse and death of starved tissue in the heart muscle, which constitutes a heart attack.
The second principle is that your heart is part of a vast circulatory system.
If all your blood vessels and arteries were connected end to end, they'd reach 60,000 miles – enough to circle the earth nearly two and a half times. The portion of this incredible network that is in and around your heart is lined with smooth muscle tissue that can contract or relax, regulating how open - or how constricted - these blood vessels are.
When this smooth muscular tissue lining the blood vessels in and around your heart is in a contracted state, reducing the diameter of the blood vessels, then high blood pressure, or hypertension, occurs. When hypertension narrows the vessels leading to the heart, it's harder for the heart muscle to get an adequate flow of nourishment into itself - so it tries to compensate by pumping even harder.
This is made even more difficult when the arteries feeding your heart muscle are lined with a build-up of fat and plaque, narrowing them still further. Your heart is working harder and harder, but as its supply lines constrict more, even less nourishment gets through. This is how heart disease and heart attacks develop.
The third principle is that the muscular walls in the parts of your circulatory system in and around your heart are connected by a communication network with your brain.
Communication takes place in two ways:
First, your brain is constantly releasing hormones into your bloodstream which tell your cardiovascular system what to do. These hormones are picked up by receptor cells lining the walls of your blood vessels. These receptor cells function like satellite dishes.
In addition, you also have nerve endings reaching all the way from your brain into the muscular vessel walls, which is an even more direct means of communication.
Messages sent from your brain, either hormonally or through nerve impulses, can tell the muscular tissue of your circulatory system to either relax or contract. With this communication network you can literally train your circulatory system to tense or relax. We'll return to this subject later.
What Is Stress and the Stress Response?
Because stress plays such a central role in hypertension and heart disease, let's look a little more closely at what stress is. The stress response is a set of changes in your body that result when you experience what you perceive to be a challenging or threatening situation. This matter of "perceived threat" is important because the effects of the stress response on your body are the same, whether the threat is real or just imagined in your mind.
The magnitude of these changes is influenced by how serious you think the situation is, and what you think about your ability to handle the threat effectively (your "appraisal" of your ability to respond). Of course, the more confident you are in your ability to handle a challenge easily, the less stress is involved. The more you appraise the challenge as a threat - even at the subconscious level - the more intense will be the stress response.
Commonly called the "fight or flight" reaction, the stress response has the beneficial effect of preparing your body to function at a higher level of efficiency which, of course, enhances your likelihood of survival.
The physiological changes include:
Increased blood pressure
Increased respiratory rate
Increased heart rate
Increased oxygen consumption (burning of fuel)
Increased blood flow to skeletal muscles
Increased muscle tone.
Downside of the Stress Response
While all these changes clearly contribute to your ability to fight or flee in an emergency, they also have a downside. If you are experiencing the stress response regularly and for extended periods of time, these physiological changes have the effect of raising your baseline level of blood pressure, and increasing cholesterol levels in your blood.
In addition, the hormones released during the stress response cause:
Increased platelet aggregation (tendency for blood cause clotting);
Increased coronary artery tone;
A surge in coronary artery pressure;
Increased glucose levels, and lipid levels;
A more rapid and powerful heart beat;
And, paradoxically, a constriction in the coronary arteries.
In short, the demands on your heart all increase.
With this understanding, it's easy to see how individuals who experience stress on a chronic basis are at greater risk for heart diseases. This connection was dramatically illustrated in a study of air traffic controllers, considered to be in a very stressful occupation, who were found to have five times the incidence of hypertension as a comparison group of second class airmen.
Stress Response’s Opposite – The Relaxation Response
The cornerstone of mind/body medicine in heart disease is regularly experiencing the relaxation response. This is a physiological state which was discovered by Dr. Herbert Benson, MD, and his colleagues at Harvard Medical School in 1974. They were studying a pattern of changes that occurs in people practicing Transcendental Meditation (TM), but it has since been learned that any form of meditation, as well as imagery, prayer, and breathing exercises can produce this healing state. [Dr. Benson, author of The Harvard Medical School Guide to Lowering Your Blood Pressure (2006), is Director Emeritus of the Benson-Henry Institute for Mind Body Medicine at Massachusetts General Hospital.]
This pattern of changes is virtually a mirror image of the stress response. The relaxation response includes the following:
First is reduced blood pressure, which is accomplished by a relaxation of the muscular lining of the 60,000 miles of your circulatory system.
Other changes include:
Reduced respiratory rate
Reduced heart rate
Reduced oxygen consumption (that is, burning of fuel)
Reduced blood flow to skeletal muscles
Reduced perspiration; and
Reduced overall muscle tension.
Immune System Benefits
The relaxation response is an antidote to the stress response, and it has also been found to enhance the functioning of the immune system [see “Your Immune System and How it Works”]. Regular practice of techniques that elicit this response also brings improved emotional well-being, and better handling of stressful life events.
What I find most exciting is the fact that regular practice of the relaxation response actually lowers your body's baseline of reactivity in stressful situations. That is, it serves as a kind of inoculation against the effects of stress, so that it actually takes more stress than before to trigger the stress response in your body.
Medical Benefits Documented
The medical benefits have been thoroughly documented, and I'd like to share with you the results of just a sampling of studies:
In one study, patients with hypertension who took an 8 week (once a week) training program achieved significantly lower blood pressure that was maintained three years later. Another study, published in the prestigious medical journal Hypertension, showed that relaxation training can reduce hypertension as much as the drugs that are ordinarily used to treat it.
In a study of patients with ischemic heart disease [reduced blood supply to the heart muscle], those who practiced the relaxation response daily for four weeks achieved significant reduction in the frequency of pre-ventricular contractions [irregular, often skipped, heartbeat].
There are also real benefits when you have surgical procedures.
- For example, a study of patients receiving angioplasty procedures [to widen a narrowed or obstructed blood vessel] showed that those practicing the relaxation response had significantly less anxiety, pain, and need for medication.
- In patients receiving heart surgery, those who received the training had significantly lower incidence of post-operative supraventricular tachycardia.
Three Relaxation Response Techniques
So, how can you go about experiencing the relaxation response on a regular basis? The three most common approaches are meditation, progressive relaxation, and mental imagery.
1. Looking first at meditation...
There are hundreds of variations of this process that have been taught down the ages. While meditation is usually associated with spiritual goals, the fact that it leads automatically to the relaxation response is a welcome benefit. The common ingredients of the many forms of meditation that lead to this healing state are quite simple.
The process should take place in a quiet environment, a setting where you can sit quietly, undisturbed, and in a comfortable position for at least fifteen to twenty minutes. Given this setting, there are only two essential steps.
Step 1 is to focus your attention on one thing that keeps you present in this moment. You might focus on the silent repetition of a word, sound, phrase, or prayer. Or it may be silently observing and feeling the rise and fall of each breath, perhaps thinking to yourself the words "breathing in... breathing out..." Whatever you choose as your focus, the point is to use this single focus to keep yourself tethered to this present moment.
Step 2 is that when you find your mind has wandered and thoughts intrude into your repetition, you just very gently return your attention back to the focus of your attention. It is natural that your mind will wander and thoughts will intrude quite often, so it's important not to judge yourself as "not doing it right" when this happens. Rather, the point is to respond with a passive attitude, as if to say "oh well..." and then come back to the repetition.
Variations on these instructions are at the core of many forms of meditation from diverse spiritual traditions. For example, rather than focusing your attention on your breath, or on a word or phrase, you may choose to sit silently and focus on a soothing and relaxing sound, such as "ohm." Whatever you choose as your focus, the simplicity of these instructions makes the approach available to virtually anyone, regardless of their spiritual or religious beliefs. This is because you can use as your repetitive focus a prayer or any other words that reinforce your beliefs (for example, "God is love"), thereby adding a further dimension of comfort to the experience.
2. Another common approach to eliciting the relaxation response is called progressive relaxation...
In this technique your physical body itself is used as the focus of attention. It may be done either lying down or sitting. One technique involves thinking of your body as a network of muscle groups. Beginning with the muscles of your feet, you focus your attention on each muscle group for a minute or so, and then move on to the next, adjacent muscle group. So you may move from the feet up to the legs, then to the buttocks, then the lower back, then the abdomen, then the chest and rib cage, then the shoulders, the upper arms, the lower arms and hands, then the neck, and finally the face and head.
As you focus on each of the muscle groups in this progression, you may imagine you are breathing your breath into it, and that as you exhale from the area, your outbreath carries with it any tension that was being held there. An alternative is to hold or clench the muscles in the area for a count of ten, and then release for a count of ten, before moving up to the next area. In either case, your attention is progressively moving up through the body, releasing tension as it goes.
3. The third major approach is mental imagery...
This involves using symbols in your mind's eye to imagine that the changes you desire in your body are actually happening.
For example, perhaps you can imagine that tight muscles are represented by a block of ice, and that as you breathe your warm breath into the area, the ice melts, and the tension and tightness melt away, leaving everything soft, warm and deeply relaxed.
Perhaps you can imagine the arteries supplying your heart becoming soft, warm, relaxed, and more open. As they soften and expand, more nutrients get through, and any unwanted materials, such as plaque or fat deposits, simply melt away and are released from the body as waste, leaving your arteries fresh and healthy.
In addition to the relaxing effects of such imagery, there's also evidence that the body has the wisdom to actually respond to the details of your images. [Dr. Collinge's Heart Disease & Hypertension audio program] can guide you through an experience of healing imagery for your heart and circulatory system.
Regardless of what form of mind/body medicine you find works best for you, the key to your success is maintaining a regular routine of practice. The benefits will accumulate over time, but it's important to establish momentum and continue it. Perhaps you may find that the early morning is your best time to practice, or perhaps during the day, or in the evening. In any case, I encourage you to set a regular pattern for your self-healing practices.
* Dr. Collinge is a leader in the development of mind-body medicine programs that involve patients as collaborators in their own healing and health. This information is reproduced with permission from Dr. Collinge's website (http://www.collinge.org).
Note: This information has not been evaluated by the FDA. It is generic and is not meant to prevent, diagnose, treat or cure any illness, condition or disease. It is very important that you make no change in your health support regimen or healthcare plan without researching and discussing it in collaboration with your professional healthcare team.