Not just athletes, but anyone for that matter tend to over exercise. Some people think that the more you exercise, the better. However this is not necessarily true. The first effect of too much exercising is muscle pain. While lactic acid build-up has been blamed for producing muscle pain, it is actually the result of three things combined. Lactate, certain acids, and ATP. During muscle contraction, these substances are released causing pain and discomfort. Scientists at the University of Utah conducted a study of mice to show how too much exercising can cause pain. Researchers isolated the substances and injected them into mouse nerve cells. At first there was no response, but when all three substances were injected at the same time, many of the nerve cells responded. The neurons responded differently depending on how much of the substances were injected. The results were similar when they performed this on humans. When the substances were combined, the subjects reported pain, swelling, and fatigue. Therefore, “The accumulation of these substances is likely what causes your muscles to hit a wall, so to speak, when you exercise too much.”
While exercise is essential for good cardiovascular health, new research is finding that too much exercise can also increase the risk of a heart attack or stroke in patients with existing heart problems. The journal, “Heart,” published a new study that tracked a decade’s worth of exercise habits and survival of more than 1,000 people with diagnosed, but stable, coronary artery disease. “Surprisingly, those who did the most strenuous daily exercise were also more likely to die of a heart attack or stroke than people who engaged in more moderate activity.”
While of course exercising regularly is extremely beneficial to your body, you must be careful to not reach an excessive amount. There are some drawbacks with prolonged and high-intensity activities.Swedish researchers studied the physical activity of more than 44,000 men periodically over 12 years. “They found that those who exercised more than five hours per week were 19 percent more likely to develop irregular heart rhythm than those who exercised less often.”
Current medical recommendations call for heart-disease patients (like everyone else) to exercise five to seven days a week. What is shocking, is that this may actually be more detrimental than beneficial. One study followed 1,038 patients with heart disease for 10 years and found that “Those who vigorously exercised daily were more than twice as likely to die of a heart attack or stroke than those who exercised only two to four days a week.” Endurance exercise also increases the risk of atrial fibrillation. It is a cardiac arrhythmia that greatly increases the risk of stroke. These health risks come with consistent vigorous exercise. It is important to exercise and be active, but always know when to stop. 
Works Cited
http://www.healthline.com/health-news/why-too-much-exercise-can-be-bad-042514
http://www.cbsnews.com/news/too-much-exercise-may-be-bad-for-the-heart/
http://www.huffingtonpost.com/brad-stulberg/health-and-fitness_b_5622445.html
http://www.ajc.com/news/lifestyles/health/too-much-exercise-bad-your-health/nfxmX/#__federated=1
http://www.dailymail.co.uk/health/article-2511045/Getting-exercise-bad-getting-all.html
http://online.wsj.com/articles/SB10001424052702304908304579561802820076042
I knew that you could overwork yourself but not to this extent. When I read this, the first thing that came to my mind was James Harrison. I could not find the same article that I saw before, but he lifts multiple times a day to stay in football shape. At one point, he would lift four times a day. Although he is one of the premier athletes in the world, everybody has a breaking point. Here is a video of him talking about the evolution of his training.
http://www.stack.com/video/14204931001/james-harrison-on-his-training-evolution/
I knew over exercising could be bad, especially in terms of weight loss but I had no idea it could affect your heart. It’s interesting that people are often told that working out would reduce their risk of heart disease and stroke, when in fact it’s possible they are increasing their risk by doing so. I was very surprised that 5 hours a week was the number given for this study. Athletes are known to train much longer than this, however they don’t appear to have increased risk of stroke or heart attack. I wonder why this is and I think it would be an interesting addition to this study.
Very well-written blog, great post! I also believe in that too much excercise is bad. There comes to a point where the body gets use to that excercise and then it no longer becomes beneficial. Also, being way too run down can negatively effect our hearts more than not working out at all. From personal experience, I have two field hockey coaches in high school. The first one we would have practice three hours a day in the summer and we did really well that year. On my junior year we had a coach that had us at practice from 8 am to 8pm six days a week. That year we did very poorly and it was because we were always so run down in time for the games. While there could be other variables such as different players and some graduated, I do storngly believe over working people will negatively effect them. Thanks for sharing!