Moderate and regular physical activity are well-known to have benefits on cardiovascular health. However, a growing body of research on intense, long-term exercise seems to favor the appearance of coronary diseases.

Nation World News reported a new study adds to the evidence that suggests extremely trained athletes may not be protected from cardiovascular diseases, like altering the arteries that supply blood, oxygen, and nutrients to the heart. Clinical and experimental data revealed the unexpected side effects of high-intensity exercise in healthy and genetically predisposed athletes.

Study on Animal Models Show How High-Intensity Physical Activity Affects Heart Health

Cardiologist Eduard Guasch from the Hospital Clinic Barcelona and the head of the IDIBAPS group of Arrhythmias and physical activity said that the prevalence of cardiovascular diseases in athletes who run marathons or engage in extreme or high-intensity sports for many years could be explained by their findings.

He and his team conducted the study titled "Long-Term Strenuous Exercise Promotes Vascular Injury by Selectively Damaging the Tunica Media: Experimental Evidence," published in the Journal of the American College of Cardiology, to show the effects of intense exercise in an animal model.

They used male rats in the experiments and divided them into three groups. The first group followed a regimen of moderate exercise with an active lifestyle, the second group was subjected to high-intensity physical activity, and the third group led a sedentary lifestyle and remained inside their cages.

Rodents exercised on the treadmill for 16 weeks, equivalent to 10 to 12 years of exercise in human lives. Then the researchers analyzed the rigidity and structure of the animals' aorta and its endothelial function to see whether there is hardening of the arteries, also known as atherosclerosis, that causes myocardial infarction.

The press release from Clinic Barcelona showed that high-intensity physical activity dilates and increases the rigidity of the aorta and carotid artery compared to a sedentary lifestyle. Moreover, it promotes rupture of the elastic coating arteries by increasing the rigidity of the cells. Guasch noted that these effects are not found in the first group who had moderate physical activity.

The team also identified mechanisms involved in the vascular remodeling that was maintained even after four weeks of the experiment. Guasch said that despite the limitations of their animal mode, their findings do not directly point to a causal relationship between intense exercise and atherosclerosis. Rather, it links to a different process similar to vascular aging.

 High-Intensity Exercise Damages Arteries That Supply Blood, Oxygen, and Nutrition to the Heart
(Photo : Pixabay/StockSnap)
High-Intensity Exercise Damages Arteries That Supply Blood, Oxygen, and Nutrition to the Heart

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Too Much Exercise Is Bad

Too much of anything is bad, even exercise. A separate study from 2017 published in the Mayo Clinic Proceedings showed that people who exercise above the current recommendations of 150 minutes of moderate physical activity a week are at higher risk of early heart disease.

Men's Health magazine reported that the researchers followed 3,175 young adults over the course of 25 years. At the end of that time period, they used CT scans to see whether there was a buildup of calcium in their arteries and whether it could be a marker for coronary disease.

They found that those who exercised three times the recommended guidelines or about 450 minutes per week of moderate physical activity are 27% more likely to show significant calcium levels in their arteries than those who exercised less than 150 minutes per week. Meanwhile, those who met the exercise recommendations were at no increased risk.

It is not the first study on such a topic, but it does not mean people should stop exercising. Instead, it reminds people that anything too much is bad for them.

RELATED ARTICLE: Is Exercise Safe? AHA Advises to be Safe While Being Active As Sudden Cardiac Death May Happen During A Session

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