Hard Labor May Augment Risk of Heart Disease

http://www.webmd.com/heart-disease/news/20130418/hard-physical-labor-may-boost-risk-of-heart-disease-stroke-studies

Summary:
Cardiovascular Diseases have been linked to high levels of stress for quite some time now, with many studies conducted regarding its influence over the well-being of the body. With this in mind, doctors have urged patients to reduce stress in any way possible, including exercise. Exercise is a common remedy for poor health, and is known to greatly relieve stress. But when does exercise affect the body in a negative way? The answer is simple: in the work place. In a recent study, researchers looked at 250 patients who had suffered a first heart attack, and 250 who had suffered a first stroke. They were then compared to a control group of 500 healthy individuals. The results were clear: stroke and heart patients were more likely to have physically demanding jobs than those in the control group. They concluded that having a less physically demanding job was associated with a 20 percent lower risk of a heart event or stroke. The exercise involved in hard labor is not tied to increasing risk of heart disease, however. The high levels of stress which stem from intense physical labor is the real killer. It is unknown why labor-linked exercise increases mental stress, but it is evident in the researcher's findings that it plays a major role in the health of those individuals. According to  Dr. Demosthenes Panagiotakos, an associate professor of biostatistics and epidemiology at Harokopio University in Athens, Greece, people with physically demanding jobs should be considered an important target group for prevention of cardiovascular disease. The study suggests that, "leisure-time exercise might be important to "balance out" the physical stress encountered in laborious jobs", as said by Dr. Tara Narula, associate director of the cardiac care unit at Lenox Hill Hospital in New York City.
In a second study, researchers followed more than 14,000 middle-aged men for an average of 3 years, and found that physically demanding work was a risk factor for developing coronary heart disease. They also found that men with physically demanding jobs who also did moderate to high levels of exercise during their leisure time had an even greater risk of developing coronary heart disease. "The results of this study suggest that additional physical activity during leisure time in those who are already physically exhausted from their daily occupation does not induce a 'training' effect but rather an overloading effect on the cardiovascular system," said Dr. Els Clays, of the department of public health at the University of Ghent, in Belgium. In all, the results of the two studies suggest that hard labor may cause high levels of stress, potentially leading to cardiovascular disease. Exercise is important, but when it leads to stress, it is counter-productive. Instead of making the body stronger, exercise induced stress can take a toll on the body, increasing risk of heart disease.

Connections:
In our studies of the human body, disease and sources of homeostatic imbalances have been commonly discussed, including cardiovascular disease. After studying the circulatory system, and examining the heart, it is interesting to learn of different factors which can ultimately lead to the dysfunction of this system. Also, the benefits of exercise in preventing such diseases has been discussed, and the fact that exercise could possibly be causing an increased risk of heart disease is very interesting. Lastly, the part that mental stress plays in this increase has to do with the interaction of the nervous system and the circulatory system, involving two different systems which have been examined in depth this year.