Is endurance exercise bad for your heart?

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1. 1

   Exercise Volume and Coronary Artery Calcification: A Systematic Review.

   CJC open (Ellingson et al.)Published Dec 30, 2025Checked Oct 4, 2026

   “Exercise volume (minutes per week) was stratified into 4 categories: low; moderate; moderate-high; and high.ResultsA total of 33 studies met the inclusion criteria: 15 reported higher CAC scores in their highest-volume groups; 8 showed no association or inverse associations; and 10 included single-cohort data. Nine of 12 comparative studies with participants exercising > 450 min/wk showed higher CAC scores in high-volume exercisers. The majority of the 9 studies reporting clinical outcomes showed no relationship or an inverse association between exercise volume and mortality or CV events. Among 5 studies assessing plaque composition, 4 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 that of less-active individuals with similar CAC scores.ConclusionsHigh-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.RegistrationPROSPERO CRD42024607693.”

2. 2

   Masters athletes with abnormal cardiovascular findings: a clinical consensus statement of the European Association of Preventive Cardiology of the ESC and the American College of Cardiology.

   European heart journal (Eijsvogels et al.)Published Jun 1, 2026Checked Oct 4, 2026

   “The purpose of this joint EAPC/ESC and ACC Clinical Consensus Statement is to provide an in-depth update on the current state of knowledge on abnormal cardiovascular findings in Masters athletes. We present an expert-based approach on the diagnostic assessment, management, and prognosis of (i) atrial fibrillation, (ii) bradyarrhythmias, (iii) ventricular arrhythmias, (iv) coronary atherosclerosis, (v) aortic dilatation, (vi) myocardial fibrosis, and (vii) exercise-induced arrhythmogenic cardiomyopathy. Clinical challenges, areas of ongoing controversy, and uncertainty and the potential underlying mechanisms are discussed. We also present future perspectives and research directives to further refine current best practice strategies. This includes the need for clinical outcome studies, dedicated randomized controlled trials in athletes, and international registries with diverse populations and longitudinal follow-up to evaluate the natural history of cardiac abnormalities and facilitate development of evidence-based approaches in the clinical management of Masters athletes with cardiovascular abnormalities.”

3. 3

   Effects of Endurance Training on Blood Pressure, Blood Pressure–Regulating Mechanisms, and Cardiovascular Risk Factors

   Hypertension (Cornelissen & Fagard)Published Sep 13, 2005Checked Sep 30, 2026

   “The meta-analysis involved 72 trials, 105 study groups, and 3936 participants. After weighting for the number of trained participants and using a random-effects model, training induced significant net reductions of resting and daytime ambulatory blood pressure of, respectively, 3.0/2.4 mm Hg (P<0.001) and 3.3/3.5 mm Hg (P<0.01). The reduction of resting blood pressure was more pronounced in the 30 hypertensive study groups (-6.9/-4.9) than in the others (-1.9/-1.6; P<0.001 for all). Systemic vascular resistance decreased by 7.1% (P<0.05), plasma norepinephrine by 29% (P<0.001), and plasma renin activity by 20% (P<0.05). Body weight decreased by 1.2 kg (P<0.001), waist circumference by 2.8 cm (P<0.001), percent body fat by 1.4% (P<0.001), and the homeostasis model assessment index of insulin resistance by 0.31 U (P<0.01); HDL cholesterol increased by 0.032 mmol/L(-1) (P<0.05). In conclusion, aerobic endurance training decreases blood pressure through a reduction of vascular resistance, in which the sympathetic nervous system and the renin-angiotensin system appear to be involved, and favorably affects concomitant cardiovascular risk factors.”

4. 4

   Exercise-based cardiac rehabilitation for coronary heart disease

   Cochrane Database of Systematic Reviews (Heran et al.)Published Jul 4, 2011Checked Sep 30, 2026

   “The eight trial-based economic evaluation studies showed exercise-based CR to be a potentially cost-effective use of resources in terms of gain in quality-adjusted life years (QALYs). AUTHORS' CONCLUSIONS: This updated Cochrane Review supports the conclusions of the previous version, that exercise-based CR provides important benefits to people with CHD, including reduced risk of MI, a likely small reduction in all-cause mortality, and a large reduction in all-cause hospitalisation, along with associated healthcare costs, and improved HRQoL up to 12 months' follow-up. Over longer-term follow-up, benefits may include reductions in cardiovascular mortality and MI. In the last decade, trials were more likely to include females, and be undertaken in LMICs, increasing the generalisability of findings. Well-designed, adequately-reported RCTs of CR in people with CHD more representative of usual clinical practice are still needed. Trials should explicitly report clinical outcomes, including mortality and hospital admissions, and include validated HRQoL outcome measures, especially over longer-term follow-up, and assess costs and cost-effectiveness.”

5. 5

   Marathon-associated sudden cardiac death: a mini review of risk perception, pathophysiological mechanisms, and prevention strategies.

   Frontiers in cardiovascular medicine (Zhang et al.)Published May 28, 2026Checked Oct 4, 2026

   “Coronary artery disease remains the predominant cause in middle-aged and older runners, whereas inherited cardiomyopathies, congenital coronary anomalies, and myocarditis are more relevant in younger athletes. We further discuss the mechanistic basis of exercise-triggered fatal events, including acute ischemia, malignant ventricular arrhythmias, myocardial fibrosis, and inflammatory myocardial injury. Current preventive approaches, including pre-participation cardiovascular screening, electrocardiography, advanced imaging, genetic evaluation in selected individuals, and rapid on-site resuscitation systems, have improved event recognition and survival outcomes, but important controversies persist regarding optimal screening intensity, interpretation of subclinical findings, and the dose-response relationship between extreme endurance exercise and cardiovascular risk. Future efforts should prioritize precision risk stratification, longitudinal evaluation of subclinical cardiovascular abnormalities, integration of wearable monitoring technologies, and standardized race-day emergency preparedness to improve the safety of long-distance running.”

6. 6

   Health benefits of physical activity: the evidence

   Canadian Medical Association Journal (Warburton)Published Mar 13, 2006Checked Sep 30, 2026

   “The primary purpose of this narrative review was to evaluate the current literature and to provide further insight into the role physical inactivity plays in the development of chronic disease and premature death. We confirm that there is irrefutable evidence of the effectiveness of regular physical activity in the primary and secondary prevention of several chronic diseases (e.g., cardiovascular disease, diabetes, cancer, hypertension, obesity, depression and osteoporosis) and premature death. We also reveal that the current Health Canada physical activity guidelines are sufficient to elicit health benefits, especially in previously sedentary people. There appears to be a linear relation between physical activity and health status, such that a further increase in physical activity and fitness will lead to additional improvements in health status.”

7. 7

   Health Benefits of Exercise

   Cold Spring Harbor Perspectives in Medicine (Ruegsegger & Booth)Published May 15, 2017Checked Sep 30, 2026

   “Overwhelming evidence exists that lifelong exercise is associated with a longer health span, delaying the onset of 40 chronic conditions/diseases. What is beginning to be learned is the molecular mechanisms by which exercise sustains and improves quality of life. The current review begins with two short considerations. The first short presentation concerns the effects of endurance exercise training on cardiovascular fitness, and how it relates to improved health outcomes. The second short section contemplates emerging molecular connections from endurance training to mental health. Finally, approximately half of the remaining review concentrates on the relationships between type 2 diabetes, mitochondria, and endurance training. It is now clear that physical training is complex biology, invoking polygenic interactions within cells, tissues/organs, systems, with remarkable cross talk occurring among the former list.”

8. 8

   Physical Activity and Public Health

   Circulation (Haskell et al.)Published Aug 1, 2007Checked Sep 30, 2026

   “Vigorous-intensity activity is exemplified by jogging, and causes rapid breathing and a substantial increase in heart rate.In addition, every adult should perform activities that maintain or increase muscular strength and endurance a minimum of two days each week.[IIa (A)] Because of the dose-response relation between physical activity and health, persons who wish to further improve their personal fitness, reduce their risk for chronic diseases and disabilities or prevent unhealthy weight gain may benefit by exceeding the minimum recommended amounts of physical activity.[I (A)] (Circulation.2007;116:1081-1093.)Key Words: benefits Ⅲ risks Ⅲ physical activity dose Ⅲ physical activity intensity I n 1995 the Centers for Disease Control and Prevention ( CDC) and the American College of Sports Medicine (ACSM) issued a public health recommendation that ''Every US adult should accumulate 30 minutes or more of moderate-intensity physical activity on most, preferably all, days of the week'' (49).The purpose of the recommendation was to provide a ''clear, concise, public health message'' that would "encourage increased participation in physical activity" by a largely sedentary US population.”

9. 9

   Exercise and Physical Activity in the Prevention and Treatment of Atherosclerotic Cardiovascular Disease

   Circulation (Thompson et al.)Published Jun 23, 2003Checked Sep 30, 2026

   “ng physical activity programs for their patients, and identifies areas for future investigation.This statement focuses on aerobic physical activity and does not directly evaluate resistance exercises, such as weight lifting, because most of the research linking physical activity and cardiovascular disease has evaluated aerobic activity.Whenever possible, the writing group has cited summary articles or meta-analyses to support conclusions and recommendations.This evidence supports the recommendation from the Centers for Disease Control and Prevention (CDC) and the American College of Sports Medicine (ACSM) that individuals should engage in 30 minutes or more of moderate-intensity physical activity on most (preferably all) days of the week.7 The American Heart Association makes every effort to avoid any actual or potential conflicts of interest that may arise as a result of an outside relationship or a personal, professional, or business interest of a member of the writing panel.Specifically, all members of the writing group are required to complete and submit a Disclosure Questionnaire showing all such relationships that might be perceived as real or potential conflicts of interest.”

10. 10

    Coronary Artery Disease in Male Athletes-Is Sport Healthy in the Long Run?

    Journal of clinical medicine (Kampka & Wybraniec)Published Jul 8, 2026Checked Oct 4, 2026

    “Despite increased longevity and lower overall CV risk, CAD remains a serious problem in athletes, being responsible for the majority of sudden cardiac death (SCD) cases in sportsmen over 30 years. Endurance athletes engaging in high-intensity training are burdened with increased coronary artery calcification (CAC) of multifactorial pathophysiology, embracing i.a. wall shear stress, excessive reactive oxygen species, inflammatory mediators and increased levels of parathyroid hormone. Thanks to improved coronary vasodilatory capacity and coronary collateralization, sportsmen are rarely affected by hemodynamically significant coronary artery stenosis, and the atherosclerotic plaques are mostly of benign, calcified morphology. The basic screening should embrace medical history, CV risk assessment and rest electrocardiogram (ECG). Stress ECG tests, computed tomography (CT) with or without contrast, and functional imaging tests are additional diagnostic options. Because CAD in athletes remains a subject of research, the article aims at bringing closer the up-to-date findings on this matter, with a summary of diagnostic tools and clinical implications.”