Exercise Volume and Coronary Artery Calcification: A Systematic Review

<h2>Abstract</h2><h3>Background</h3> Exercise confers numerous health benefits, including a reduction in all-cause and cardiovascular (CV) mortality. However, conflicting evidence suggests high-volume endurance exercise may increase coronary artery calcification, a robust predictor of CV events. This systematic review investigated the relationship between exercise volume and coronary artery calcium (CAC) scores. <h3>Methods</h3> A systematic search of Medline, EMBASE, PubMed, and Cochrane Library (1990 to November 26, 2025) was conducted. Studies reporting exercise volume and CAC scores were included. The methodological index for non-randomized studies (MINORS) scale was implemented to test study quality. Exercise volume (min/wk) was stratified into four categories: low, moderate, moderate-high, and high. <h3>Results</h3> Thirty-three studies met the inclusion criteria: 15 studies reported higher CAC scores in their highest-volume groups; eight studies showed no or inverse associations; 10 studies included single-cohort data. Nine of 12 comparative studies with participants exercising >450min/wk showed higher CAC scores in high-volume exercisers. The majority of the nine studies reporting clinical outcomes showed no relationship or an inverse association between exercise volume and mortality or CV events. Among five studies assessing plaque composition, four reported a more benign, calcified plaque composition among their high-volume exercisers, representing a potential mechanism for the lower risk of CV events and mortality reported in this population compared to less active individuals with similar CAC scores. <h3>Conclusion</h3> High-volume exercisers may have higher CAC scores compared to less active cohorts. Despite elevated CAC scores, lower mortality and CV event rates observed in these groups challenge the clinical significance of this observation.