A new study reveals a link between upper body muscle quality and a reduced risk of heart attacks and death, findings that could reinforce the role of physical activity in preventing heart disease.
The researchers reported that people with higher quality muscle mass in their back and chest muscles were less likely to suffer heart attacks or die during a 10-year follow-up period.
These findings came from a study published in the journal Radiology, in which researchers used artificial intelligence techniques to analyze CT scan images of 1,722 patients who participated in a cardiac CT scan trial in Scotland.
The patients, with an average age of 58, underwent imaging tests between 2010 and 2014 due to chest pain, and were then followed for ten years to monitor for heart attacks and deaths. During this period, 133 patients died, while 106 others suffered heart attacks, some of which were fatal.
The researchers identified what is known as "skeletal muscle attenuation," an index in CT scans that reflects muscle quality; low values indicate increased fat within the muscles, meaning lower quality. They found that an improvement in this index is associated with a reduced risk of heart attacks and death.
These examinations show the muscles of the upper body, especially the back muscles, the pectoralis major muscle, and the intercostal muscles, within what is known as computed tomography coronary angiography (CCTA).
The researchers indicated that muscle size alone was not associated with injury risk, but rather muscle quality and composition were the most important factors.
Experts explained these results by saying that higher quality muscles often reflect a higher level of physical activity, which has a positive impact on cardiovascular health.
Professor Brian Williams, chief scientific and medical officer at the British Heart Foundation, said that people with greater muscle mass may be more physically active, which improves heart health, adding that regular exercise can reduce the risk of heart disease by up to a third.
The researchers noted that every 10-point increase in muscle quality was associated with a 31% lower risk of heart attack and a 39% lower risk of death during the follow-up period, even after taking into account factors such as age, sex, and arterial calcification.
The team also found no clear relationship between the amount of body fat and the risk of heart attacks, which reinforces the importance of focusing on muscle quality and not just weight.
Professor Michelle Williams, the lead researcher on the study, explained that the findings open the door to a deeper understanding of the role of muscles in heart health, but stressed the need for more research, particularly on the impact of different types of exercise such as cycling, planks, and Pilates on muscle and heart health.
