People with strong chest and back muscles are less likely to have a heart attack or die prematurely, according to an analysis using artificial intelligence led by the University of Edinburgh. The study, published in the journal Radiology, examined hospital scans of 1,722 patients, mostly in their 50s, who had chest pain.
AI Reveals Muscle Density Link
Researchers used AI to assess skeletal muscle attenuation—the brightness or darkness of muscle in a scan. Denser muscle appears lighter because more X-ray beams bounce off it, indicating better quality muscle with less fat. For every 10-point increase in scan brightness, a person was 31% less likely to have a heart attack and 39% less likely to die within 10 years after the scan.
Prof Michelle Williams, senior author of the study, found the results so compelling that she now exercises twice a week and walks an hour daily. “It is fascinating that people’s skeletal muscle could be linked to their risk of having a heart attack,” she said. “The muscles which show up in the scans we use are principally the back muscles, part of the pectoral muscles, and the intercostal muscles between the ribs. So I am now personally interested in exercises like cycling, planks and pilates, which I enjoy and may have an effect on these muscles.”
Muscle Composition Matters More Than Size
The size of people’s muscles was not linked to heart attack or early death risk, suggesting composition—not bulk—is key. Researchers suspect those with greater muscle density exercise more, reducing their risk. Future routine heart scans could identify patients with poorer muscle quality, allowing targeted interventions such as exercise programs, closer monitoring, or preventive drugs.
Prof Bryan Williams, chief scientific and medical officer at the British Heart Foundation, which part-funded the study, said: “It is likely that people in this study with more dense muscle mass were more physically active and as a result may have better heart health. That is yet more evidence supporting the power of exercise.”
The findings underscore the potential of AI-enhanced imaging to reveal hidden risk factors and promote preventive health strategies.
