Research

Mixed

Prolonged strenuous running (e.g., marathons, ultra-marathons) causes acute, transient elevations in biomarkers typically associated with pathology (such as creatine kinase, cardiac troponins, and liver enzymes), but these changes represent physiological stress and tissue microtrauma rather than chronic disease or injury.

If you have recently completed a long run or race, expect your blood work to show elevated markers for muscle, liver, or heart stress. These results are transient and reflect the physical effort, not disease. Inform your clinician about recent strenuous exercise to avoid misdiagnosis.

GoodQualifiesHIGH confidence
Strenuous running exercise can produce changes to biomarkers that are normally associated with disease and injury, but these do not necessarily reflect chronic pathology.
Stephen R. Bird et al. · Annals of Clinical Biochemistry International Journal of Laboratory Medicine · 2013

Why this rating

Review article synthesizing multiple studies on marathon and ultra-endurance events.

Source

Acute changes to biomarkers as a consequence of prolonged strenuous running

Stephen R. Bird et al. · Annals of Clinical Biochemistry International Journal of Laboratory Medicine · 2013

DOI 10.1177/0004563213492147

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DOI resolved against Crossref · corpus check 2026-06-10

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