Everyone knows that exercise is good for the heart, so the recent news that excessive exercise can block arteries may shock many people.
This study, widely reported by the media, found that very active people have higher coronary artery calcium (CAC) scores than less active people. The CAC score measures the calcium content in the walls of coronary arteries, which are the arteries that supply blood and oxygen to the heart muscle.
An increase in calcium in the coronary arteries may increase a person’s risk of heart attack because the presence of calcium in the coronary arteries indicates that there may also be a buildup of plaque, called atherosclerosis. Plaque buildup is usually the result of an unhealthy lifestyle, such as smoking, drinking, being overweight, and lack of exercise. Therefore, doctors often use CAC scores to identify people at risk of heart disease.
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Researchers from the Korean University School of Medicine and the Bloomberg School of Public Health at Johns Hopkins University in the United States analyzed more than 25,000 healthy adults (mainly men) aged 30 and over between March 2011 and December 2017. Coronary Artery Calcification. Participants underwent two full examinations during the study period to monitor changes in their coronary arteries.
The researchers wanted to find out whether there is a link between physical activity and increased coronary artery calcification.
All study participants completed a questionnaire to determine the amount of exercise they performed each week. Nearly half of the participants (47%) were classified as inactive, 38% were classified as moderately active, and 15% were classified as extremely active (equivalent to running 6.5 kilometers per day).
Compared with participants who were less physically active, those who were more physically active tended to be older and less likely to smoke.
Scans performed at the beginning of the study showed that the average CAC score was 9.5 for the inactive group, 10.2 for the moderately active group, and 12 for the highly active group. At the end of the study, the average score of people who exercised moderately and vigorously increased by 3 to 8 points. Therefore, moderate and vigorous exercise seems to increase the accumulation of calcium deposits in the arteries.
The benefits of exercise are beyond doubt
However, the researchers did not find a link between a higher coronary artery calcification score caused by exercise and a cardiovascular “event” (such as a heart attack or stroke). Therefore, headlines claiming that exercise “increases the risk of heart attack” are both wrong and dangerous. In fact, the researchers warned against such explanations. They concluded: “The cardiovascular benefits of physical exercise are beyond doubt.”
The health benefits of exercise are significant. The higher the level of exercise, the lower the risk of heart disease and premature death. This suggests that although exercise may increase CAC scores, it reduces the risk of cardiovascular diseases, such as heart attacks and strokes. The benefits of exercise greatly outweigh the risks. People should do at least 150 minutes of moderate-intensity exercise or 75 minutes of vigorous exercise every week.
Interestingly, the increase in calcium density in the coronary arteries caused by exercise may have a protective effect because it reduces the likelihood of rupture of plaque in the arteries, which can cause heart attacks. So doctors need to be careful when interpreting the CAC scores of healthy people.
This article is republished from – The Conversation – Read the – original article.
