Marathon Running Acutely Elevates Cardiac Injury Biomarkers and Alters Heart Structure/Function
Background
The intense physical demands of marathon running are known to induce various cardiovascular effects, but the precise nature and clinical significance of these acute changes remain a subject of debate. While some studies suggest transient, benign physiological adaptations, others raise concerns about potential harmful cardiac alterations. Understanding these immediate post-marathon responses is crucial for athletes, coaches, and clinicians to better assess risk and recovery. This systematic review and meta-analysis specifically aimed to comprehensively characterize the acute cardiac effects, including myocardial biomarkers, cardiac morphology, and function, immediately following a marathon race in healthy adults.
Study Design
Researchers conducted a systematic review and meta-analysis by searching PubMed, Embase, and SPORTDiscus for studies published up to April 11, 2025. Inclusion criteria required primary data in English from healthy adults completing a road marathon, with quantitative pre- and post-marathon cardiac effect measurements. Data on myocardial biomarkers, morphology, and function were extracted. Random-effect meta-analyses were performed on 69 eligible studies (totaling 3274 participants, aged 30-55 years, >80% men), with 49 studies contributing to meta-analyses across three biomarkers, 18 echocardiography metrics, and five cardiac MRI metrics. Meta-regression analyses were conducted for metrics with ≥7 studies.
Results
Marathon running consistently induced significant acute increases in circulating myocardial injury biomarkers. Specifically, troponin T levels rose by +42 (32.6, 52.3) ng/L (p<0.001), troponin I by +77 (55.1, 98.3) ng/L (p<0.001), and N-terminal pro B-type natriuretic peptide (NT-proBNP) by +114 (89.0, 138.6) ng/L (p<0.001). These elevations indicate acute myocardial stress or injury. > Echocardiography revealed post-marathon decreases in left ventricular (LV) volume and diastolic function, alongside reduced right ventricular (RV) systolic function, while RV end-systolic and diastolic volumes increased. Conversely, cardiac MRI data indicated an increase in LV ejection fraction. Meta-regression analyses further demonstrated that these acute cardiac responses varied significantly based on participant age, sex, training status, and marathon performance, highlighting the individual variability in physiological adaptation to extreme exertion.
Key Findings
- Marathon running increased circulating troponin T by +42 ng/L (p<0.001).
- Troponin I levels rose by +77 ng/L (p<0.001) post-marathon.
NT-proBNPincreased by +114 ng/L (p<0.001) after marathon completion.- Echocardiography showed decreased
LVvolume and diastolic function, and reducedRVsystolic function. - Cardiac MRI indicated an increase in
LVejection fraction post-marathon.
Why It Matters
This comprehensive meta-analysis provides robust evidence that marathon running consistently induces acute, measurable changes in cardiac biomarkers, structure, and function. For athletes and coaches, this means understanding that elevated troponins and NT-proBNP are common post-marathon physiological responses, not necessarily indicative of pathology in healthy individuals, though their clinical significance remains to be fully elucidated. Runners should be aware of these transient cardiac changes, but the current data does not suggest a need for immediate concern without other symptoms. For clinicians, it underscores the importance of interpreting these biomarker elevations in the context of extreme exercise, avoiding misdiagnosis of acute coronary syndromes. Further research is essential to determine the long-term implications and potential for harm, especially in susceptible individuals or those with underlying conditions.
marathon
running
cardiovascular
cardiac-function
myocardial-injury
biomarkers