So what is the #1 thing a man can do to improve his sex life, general health and cognition. Well, there are many top candidates: exercise, a whole foods diet (Low Fat, Mediterranean, etc.), sleep, sexual intercourse and possibly losing weight if one is overweight or obese. But there is another top contender and the great majority of men not only do not practice it but are not even aware that it exists.
Of course, what I am talking about is implementing the Relaxation Response into your daily lifestyle. Most men - and I admit myself included until recently - do not want to hear about relaxation. It's boring, a waste of time and on and on. But medical researchers, when they use the term Relaxation Response, are not referring to a nice vacation in Maui, a good round of gold or even "relaxing" in front of the television. Researchers are referring to a very profound physical and measurable clinical response that occurs when you do certain activities. And, usually, these activities include various forms of meditation, Progressive Muscle Relaxation, autogenic training and a few other similar practices.
NOTE: Pursuing the Relaxation Response through meditation or Progressive Muscle Relaxation need have NOTHING to do with religious practice. I personally practice what is called "secular mediation" as much as possible, which has absolutely no spiritual connotations. No offense to anyone who does incorporate the spiritual into their meditation, but my point is simply that everyone should meditate, do PMR, autogenic training, etc.
These effects are stunning to say the least and include short term changes including a drop in blood pressure, a decrease in stress hormones and so on. However, as we'll document below, these changes are much more far-reaching than simple reversal of the "fight or flight response".
So what is the formula for achiving a Relaxation Response. Well, the easiest is probably Progressive Muscle Relaxation, which simply involves tensing and relaxing the muscles in a quiet environment. It has a vast clinical and research track record proving its worth and utility. However, one study points out that any technique that follows these four simple points will produce the Relaxation Response:
The authors also noted that "sitting quietly with the eyes either open or closed failed to produce the same changes." So, yes, you can keep it simple - just not too simple. But, again, there are many other techniques, especially meditation, that will produce a Relaxation Response. (And there are even many types of meditation.)
Below I will present evidence that getting the Relaxation Response to work for you is one of the biggest things that you can do and is the b>missing ingredientnbsp; Don't believe me? Check out these reasons to get busy Relaxin'!
1. Blood Pressure. The Relaxation Response can have a profound effect on blood pressure, especially in hypertensive patients. In fact, average responses can be about as much as some standard blood pressure medications. For example, one study on patients with high blood pressure who were already on medications lowered average blood pressure from 146 and 92 mm to 135 and 87 mm, respectively.  This is an impressive drop for patients who had already been corrected via pharmaceuticals. Admittedly, this was an older study but a number of follow-up studies have verified similar results and I include one of those in my page on Progressive Muscle Relaxation.
Of course, high blood pressure is a leading risk factor for erectile dysfunction, stroke and men with high blood pressure have been found very often to have low testosterone as well. (Low testosterone probably tends to cause hypertension rather than the other way around though.) See my link on High Blood Pressure and Erectile Dysfunction for more information.
2. Nitric Oxide. Meditation undoubtedly lowers blood pressure by several mechanisms, including the diminishing of a variety of stress hormones. However, there is another property of meditation that should be of interest to men everywhere: it increases nitric oxide according to a study on Zen meditation.  Of course, nitric oxide is the key molecule involved in initiating erections (and dilating arteries) and it is remarkable that both movement (exercise) and sitting quietly with focused attention (meditation) can both increase NO.
3. Anti-Aging and Telomerase. If you meditate for just one reason, do it to to slow down aging. Sound too good to be true? Well, one the core theories of aging centers around the shortening of your chromosomes, i.e. tlomeres through the action or inaction of the telomerase enzyme. Meditation was found in a 2011 study to actually increase telomerase activity which will protect your chromosomes.  Many things that increase stress have been found to shorten telomeres and thus likely accelerate aging, so this was no major surprise to researchers. See my link on Telomeres and Telomerase for more information.
3. Brain Size (Density). Don't you wish there was a supplement that would increase the size of your brain? Well, why not meditate instead? There is strong evidence that meditators increase the size (density of neurons) in many key parts of their brain. It is not wonder since meditation a) decrease cortisol which is very hard on the brain and b) increases blood flow to many importants of the brain owing to the requirement for concentration and focus.
What areas of the brain are affected positively by meditation? Well, there have been a number of studies on this. One of them summarize by saying that meditation affected the "dorsolateral prefrontal and parietal cortices, hippocampus / parahippocampus, temporal lobe, pregenual anterior cingulate cortex, striatum, and pre- and post-central gyri."  Notice the hippocampus in that list, which is the seat of one's memory and is one of the parts of the brain attacked by Alzheimers and dementia.
4. Risk of Dying (Mortality). There are indications that meditation can, for many people at least, increase your life span by decreasing your risk of dying. For example, one study of seniors with hypertension found significantly decreased mortality rates.  Study authors noted "a 23% decrease in the primary outcome of all-cause mortality..., a 30% decrease in the rate of cardiovascular mortality and a 49% decrease in the rate of mortality due to cancer." Not bad for 15-20 minutes of work per day, eh?
5. Cortisol Reduction. As I have pointed out in a number of places on this site, Meditation and PMR are famed for decreasing cortisol. Of course, high cortisol lowers testosterone, decreases muscle mass and injures the brain. For more information, see this link on Stress Management.
6. Intelligence. This one is hard to prove, but a couple of studies have shown that meditation may actually increase general intelligence - that's how good it is for the brain. 
7. DHEA. Meditation should increase testosterone, because of its cortisol-lowering actions but there is no hard evidence of that. However, one hormone that does seem to be affect positively by meditation is DHEA. Practitioners of TM were found to have increased levels of DHEA  and, although study results have been somewhat inconclusive, it is safe to say that DHEA helps some men at least with libido, memory and energy levels.
8. Work Performance. One very easy relaxation technique is simple to say the word "one" whenever you exhale and "passively disregard other thoughts." One study found a significant increase in work performance based on things like energy, concentration, problem-handling, etc. 
9. Neurotic Behavior, Panic Disorder, OCD (Obsessive Compulsive Disorder) and Anxiety. Progressive Muscle Relaxation has a solid research and clinical track record with all of these stress-related disorders. See my link on The Miracle of PMR for details. And considering how well PMR does with neurotic behavior, this study of Transcental Meditation on African American adults is interesting: researchers found that there was less neurotic behavior resulting from TM than PMR. 
10. Depression. One very common theme on the Peak Testosterone Forum is depression. Of course, sometimes depression results from low testosterone. However, sometimes depression can lead can cause men many issues, including loss of libido and erectile strength. (See my link on Depression and Erectile Dysfunction for some basic information.) I list many Depression Cures and Helps, but one that will be a big help for certain subpopulations of men: Progressive Muscle Relaxation. This form of The Relaxation Response has been shown in studies on men recovering for cardiovascular disease and cancer to help improve depression.  NOTE: Mindfulness meditation was shown in one meta-analysis to not be significantly helpful with depression. 
11. Immunity (Colds and Flus). Yes, it looks like the Relaxation Response can even help prevent the common cold according to one study on college students.  A recent study on children looks like this may be the case for meditation as well.  Mindfulness meditation is associated with increased Natural Killer Cell activity as well.  Meditation has also been found to increase antibody response to the flu, which should translate to increased protection. 
12. Insomnia. Many studies have shown that the Relaxation Response can help in many cases with insomnia. PMR has done particularly well.  but meditation also has studies as well.  For other research-backed information, see this link on Practical Sleep Aids.
13. Norepinephrine (noradrenaline). This stress hormone actually puts the brakes on erections.  One study found that a standard Relaxation Response produced reduced stress in a way that is typical of decreased noradrenaline.  However, one smaller, older study found that noradrenaline increased post-meditation. 
14. Headache. Studies have shown that meditation can be a powerful tool in the treatment of headache relief. One study noted good results with cluster and migraine sufferers for example. 
15. Arthritis. A very common and debilitating condition is arthritis and research has shown that the Relaxation Response can help with this condition. For example, one study using PMR and guided imagery showed that they significantly improved both mobility and pain in female patients.  This study was on those with osteoarthritis but meditation has been shown to help with rheumatoid arthritis as well. 
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