Is exercise helpful if you are under a lot of stress? Absolutely!

While exercise may not change the circumstances causing the stress, exercise can help you cope with it better. This is very important because stress is clearly related to health problems.

For some tips, read on.....

THE "MIND-BODY" CONNECTION

First, just in case there is any doubt about how powerfully the mind can influence human physiology, consider the following details:

Minor Examples:

Research shows that something as simple as the phone ringing can cause an employee's blood pressure to rise. This physiologic response would be imperceptible to the individual, yet could lead to health problems.

More Dramatic Examples:

When William Friedkin's movie "The Exorcist" was released in 1973, it was reported that some viewers were so shocked they vomited. This is a pretty dramatic example of how psychic imagery can affect people.

But, if that isn't impressive enough, consider this almost unbelievable research study conducted several decades ago:

In 1959, the Journal of Physiology published a paper evaluating the cardiovascular responses to psychic stress. In this study, medical students were subjected to false scenarios, however, they were led to believe they were real.

Researchers performed a variety of hoaxes to measure how stress affected heart rate and blood flow. In order to create a realistic stress response, the psychological scenarios were extreme and sometimes bizarre. These included:

• administering a grueling oral exam in the area of physiology and then severely criticizing the students with each response, whether or not it was correct
• convincing the students that, after inserting a needle into their arms, something had gone wrong and they were losing a large amount of blood
• dissecting open the stomach of a rabbit and then telling the student he had to taste the contents

In most of these experiments, the medical students believed the stories and panicked, which was the whole point of the study in the first place: to examine the effects of the autonomic nervous system during stress. In one student, resting heart rate increased from 80 bpm to 140 bpm after he believed he was experiencing severe blood loss. (Blair DA, et al. 1959).

Extreme Examples:

Physiologic reactions even more dramatic than those listed above can occur as a result of psychic stress. Consider when someone faints at the sight of blood, or, a person who develops panic attacks when they have to get on an airplane, or, deliver a public speech.

In some cases, stress could actually be life-threatening: Immediately following the Northridge earthquake in January 1994, the number of ER visits by people complaining of chest pain spiked.

Sports Examples:

One of my favorite examples of the power of suggestion in athletes is this one (Beedie CJ, et al. 2006):

Elite cyclists were told they were going to participate in a study of how caffeine might affect their cycling performance. In this study, the cyclists were told they would receive 3 "treatments": placebo, caffeine 4.5 mg/kg, and caffeine 9 mg/kg. After each capsule, they had to complete a time-trial as fast as they could.

When the results were analyzed, the race times after the 4.5 mg/kg caffeine dose were better than after placebo, and, the times after the high caffeine dose were better than the lower caffeine dose.

But, here is the surprise: no caffeine was given at any time! All athletes received a placebo during each of the 3 time-trials! The athletes performed better only because they believed they had received caffeine.

(This topic is discussed in greater detail in: "Don't Underestimate the Power of Suggestion".)

IMPACT OF CHRONIC STRESS ON HEALTH

So, as summarized above, stress can cause dramatic and immediate effects on the body. This can lead to health problems. A study from UCLA a number of years ago showed that mental stress (public speaking) was able to produce detrimental effects on the heart and blood pressure similar to exercise in patients with coronary artery disease (Rozanski A, et al. 1988).

But, when a person endures stress over months to years, additional health problems can occur:

Obviously, for a variety of reasons, stress is an unhealthy thing!

MANAGING STRESS

Strategies for managing stress might include the following:

Below, I will review some research on the benefits of different types of exercise.

HOW EXERCISE CAN HELP WITH STRESS

The bottom line is this: Regular exercise can help you cope with stress better. It can actually diminish the body's physiologic response to stress. But how is this accomplished?

The effects of stress and exercise on the body can be shown by measuring circulating levels of various hormones:

Stress causes the release of hormones from the adrenal gland and nerve endings. They include: cortisol, epinephrine (adrenaline), and norepinephrine (noradrenaline). These are often called "stress hormones."

Vigorous exercise can also stimulate the release of these hormones. (This is one explanation why too much exercise can be detrimental!) However, the brain can produce "anti-stress" hormones as well: endorphins, serotonin, and a newly discovered molecule called "galanin." Galanin can modulate (reduce) the actions of norepinephrine. Exercise has been shown (in animal studies) to stimulate the release of galanin.

So, for example: Stress increases the output of norepinephrine. Norepinephrine has powerful effects on heart rate and blood pressure. In contrast, exercise, by promoting the output of galanin, can diminish the effects of norepinephrine.

WHAT KINDS OF EXERCISE ARE HELPFUL AND HOW MUCH?

Below, I will discuss 4 different types of exercise and how they affect the stress response in humans:

• aerobic exercise
• resistance exercise
• Tai Chi
• yoga

Aerobic Exercise

Plenty of research exists showing that various forms of aerobic exercise are beneficial for controlling stress. Here is just one example:

• Patients with hypertension were evaluated to see if regular aerobic exercise would modify their cardiovascular responses to stress. Subjects were sedentary, overweight, and had hypertension. The aerobic exercise program consisted of 10-min of warm-up, 45-min of biking, walking, and jogging, followed by 10-min of cool-down. This was done 3 or 4 times per week for 6 months.

At the end of the study, the subjects had lower resting blood pressure. And, in response to mental stress, their BP and HR responses were diminished. Thus, regular aerobic exercise modified the cardiovascular response to stress in patients with hypertension (Georgiades A, et al. 2000).

Resistance Exercise

Resistance exercise can also be helpful, but here is an interesting distinction between aerobic exercise and resistance exercise:

• Thirty-six men with a "type-A" personality were randomized to receive 12 weeks of either aerobic exercise, or, a combination of resistance exercise with flexibility exercises. The aerobic exercise program consisted of walking, jogging, and stair-climbing. Each session started with 10-15 min of warm-up, followed by 35-min of continuous exercise. This was done 3 times per week for 12 weeks. The other program consisted of 20-min of flexibility exercises and 30-min of circuit training on Nautilus weight-stack machines. This program was done 2-3 times per week for 12 weeks.

Both types of exercise improved "type-A" behavior. However, only the aerobic exercise program reduced the spikes in BP and HR after men were exposed to stress (Blumenthal JA, et al. 1988).

Tai Chi

Tai Chi is an ancient Chinese practice that involves meditative rhythmic balance movements. It, too, is effective for lowering stress:

Researchers in Japan studied the effects of Tai Chi in elderly patients with coronary heart disease. Patients who had sustained a cardiac event were randomized to perform Tai Chi 4 times per week or conventional cardiac rehab. The study lasted 1 year.

After 1 year, it was found that the Tai Chi patients had better autonomic nervous system status (defined as "baroreflex sensitivity") (Sato S, et al. 2010). This adaptation is thought to be beneficial for patients with coronary heart disease as it may lower their risk for future cardiovascular events.

Yoga

Yoga appears to be effective for controlling stress. This has been documented by measuring circulating levels of stress hormones, and, by monitoring blood pressure:

• In one study, when women were exposed to stress, circulating levels of stress hormones were lower in women who practiced yoga regularly compared to women who were novices (Kiecolt-Glaser JK, et al. 2010).

• Researchers from India showed that yoga performed for 10 days could reduce systolic blood pressure, reduce blood levels of "inflammatory" biomarkers, and promote weight loss in overweight and obese subjects. These effects were demonstrated in both men (Sarvottam K, et al. 2012) and women (Yadav RK, et al. 2012). All of these changes are thought to help lower cardiovascular risk.

But is there any proof that yoga can reduce the incidence of a major cardiovascular event? Not yet, it seems. A Cochrane Review, published December 12, 2012, stated that, so far, there is no hard evidence that modifying these risk factors by performing yoga has any impact on the incidence of sustaining a cardiac event in patients who have already had one (ie., "secondary" prevention) (Lau HL, et al. 2012).

So what does this mean? It would be wrong to conclude that yoga isn't helpful for patients with cardiovascular disease. The Cochrane Review simply states that the "perfect" study hasn't yet been done on this topic. But, because other research shows that yoga can reduce both stress hormones and cardiovascular indicators of stress, it seems to me that yoga is definitely beneficial for people undergoing stress.

SUMMARY

If you are under a lot of stress at work, or, in your personal life, regular exercise can help. Various forms of exercise can moderate your body's reaction to stress. This has been documented by measuring circulating levels of stress hormones, and, by monitoring cardiovascular responses (HR, BP) to stress. Aerobic exercise is clearly effective, but new research is showing that meditative forms of exercise such as Tai Chi and yoga are also helpful.

FOR MORE INFORMATION

Readers may also be interested in these related topics:

• Don't Underestimate the Power of Suggestion
• Exercise for Coronary Artery Disease
• Exercise for Depression
• Exercise for Hypertension
• Yoga

EXPERT HEALTH and FITNESS COACHING

Stan Reents, PharmD, is available to speak on this and many other exercise-related topics. (Here is a downloadable recording of one of his Health Talks.) He also provides a one-on-one Health Coaching Service. Contact him through the Contact Us page.

FOR PHYSICIANS AND EMPLOYERS

For physicians and employers who are skeptical of the effectiveness of web-based health/exercise coaching, there is this study:

• Researchers randomly assigned 309 adults to a web-based multimedia health promotion program designed to help reduce stress in the workplace, or, to a wait-list control condition. The group that received the web-based health coaching reduced their stress, increased their knowledge of depression and anxiety, and developed a healthier approach to alcohol consumption (Billings DW, et al. 2008).

REFERENCES

Beedie CJ, Stuart EM, Coleman DA, et al. Placebo effects of caffeine on cycling performance. Med Sci Sports Exerc 2006;38:2159-2164. Abstract

Beedie CJ, Coleman DA, Foad AJ. Positive and negative placebo effects resulting from the deceptive administration of an ergogenic aid. Int J Sport Nutr Exerc Metab 2007;17:259-269. Abstract

Billings DW, Cook RF, Hendrickson A, et al. A web-based approach to managing stress and mood disorders in the workforce. J Occup Environ Med 2008;50:960-968. Abstract

Blair DA, Gover WE, Greenfield AD, et al. Excitation of cholinergic vasodilator nerves to human skeletal muscles during emotional stress. J Physiol 1959;148:633-647. Abstract

Blumenthal JA, Emery CF, Walsh MA, et al. Exercise training in healthy type A middle-aged men: Effects on behavioral and cardiovascular responses. Psychosom Med 1988;50:418-433. Abstract

Blumenthal JA, Fredrikson M, Kuhn CM, et al. Aerobic exercise reduces levels of cardiovascular and sympathoadrenal responses to mental stress in subjects without prior evidence of myocardial ischemia. Am J Cardiol 1990;65:93-98. Abstract

Georgiades A, Sherwood A, Gullette ECD, et al. Effects of exercise and weight loss on mental stress-induced cardiovascular responses in individuals with high blood pressure. Hypertension 2000;36:171-176. Abstract

Kiecolt-Glaser JK, Christian L, Preston H, et al. Stress, inflammation, and yoga practice. Psychosom Med 2010;72:113-121. Abstract

Lan C, Chen SY, Wong MK, et al. Tai Chi training for patients with coronary heart disease. Med Sport Sci 2008;52:182-194. (no abstract)

Lau HL, Kwong JS, Yeung F, et al. Yoga for secondary prevention of coronary heart disease. Cochrane Database Syst Rev 2012;12:CD009506. Abstract

Rozanksi A, Bairey CN, Krantz DS, et al. Mental stress and the induction of silent myocardial ischemia in patients with coronary artery disease. N Engl J Med 1988;318:1005-1012. Abstract

Rozanski A, Blumenthal JA, Kaplan J. Impact of psychological factors on the pathogenesis of cardiovascular disease and implications for therapy. Circulation 1999;99:2192-2217. Abstract

Sarvottam K, Magan D, Yadav RK, et al. Adiponectin, interleukin-6, and cardiovascular disease risk factors are modified by a short-term yoga-based lifestyle intervention in overweight and obese men. J Altern Complement Med December 4, 2012. Abstract

Sato S, Makita S, Uchida R, et al. Effect of Tai Chi training on baroreflex sensitivity and heart rate variability in patients with coronary heart disease. Int Heart J 2010;51:238-241. Abstract

Yadav RK, Magan D, Mehta N, et al. Efficacy of a short-term yoga-based lifestyle intervention in reducing stress and inflammation: preliminary results. J Altern Complement Med 2012;18:662-667. Abstract

ABOUT THE AUTHOR

Stan Reents, PharmD, is a former healthcare professional. He is a member of the American College of Lifestyle Medicine (ACLM) and a member of the American College of Sports Medicine (ACSM). In the past, he has been certified as a Health Fitness Specialist by ACSM, as a Certified Health Coach by ACE, as a Personal Trainer by ACE, and as a tennis coach by USTA. He is the author of Sport and Exercise Pharmacology (published by Human Kinetics) and has written for Runner's World magazine, Senior Softball USA, Training and Conditioning and other fitness publications.