Research

Mixed

Participating in a high-altitude ultramarathon (161 km) causes significant, transient elevations in cardiac troponin I (cTnI) and creatinine levels, with higher intensity (faster finish times) correlating with greater cTnI release.

If you complete a 100-mile race, expect your cardiac and kidney biomarkers to spike temporarily. This is a normal physiological response to extreme stress, not necessarily a sign of injury. Ensure adequate recovery and hydration, but do not assume permanent damage based on post-race blood tests alone.

ModerateSupportsMEDIUM confidence
Mean cTnl increased from 0.001 to 0.047 ng/mL (p = 0.005)... Mean creatinine increased from 0.93 to 1.17 mg/dL (p < 0.05)... runners who finished the race in faster time had higher cTnl levels compared to those who finished the race close to the 30-hour cut-off finish time (P = 0.005).
Morteza Khodaee et al. · International Journal of Sports Medicine · 2015

Why this rating

Small sample size (n=10 paired, n=21 post-race), observational design, and use of a portable analyzer which may have different sensitivity than central lab assays.

Source

Effects of Running an Ultramarathon on Cardiac, Hematologic, and Metabolic Biomarkers

Morteza Khodaee et al. · International Journal of Sports Medicine · 2015

DOI 10.1055/s-0035-1550045

cohort · n=31Cited 35×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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