Marathon Running Triggers Temporary Heart Biomarker Spikes, Study Finds

Marathon running has grown in popularity as a test of endurance and fitness. Yet the impact of such extreme exertion on the heart remains unclear, with researchers balancing transient changes against potential long-term stress. A recent meta-analysis of over 3,200 runners showed sharp rises in cardiac biomarkers like cTnT, cTnI, and NT-proBNP within an hour after finishing a marathon. These levels often exceeded clinical thresholds for heart attacks or heart failure. However, echocardiographic evaluations found only modest changes in cardiac chamber dimensions and left ventricular ejection fraction, all within safe clinical limits.

Cardiac MRI scans revealed no consistent structural damage to the heart muscle after the race. Biomarker elevations and functional changes varied depending on the runners’ finishing times, training levels, age, and sex. The study also noted that most participants were men, leaving a gap in understanding how these effects apply to women.

Researchers emphasised the need for longitudinal studies to track the long-term cardiac health of endurance athletes. They also called for more inclusive research, involving women, diverse ethnic groups, and detailed training data to improve accuracy. The findings suggest marathon running causes temporary cardiac biomarker spikes without immediate structural harm. These results highlight the importance of further study to refine exercise guidelines and personalised risk assessments. Future work must address current research gaps to ensure broader applicability.