Background: Exercise-induced gastrointestinal syndrome (EIGS) is characterized by increased intestinal permeability, splanchnic hypoperfusion, and gastrointestinal (GI) distress symptoms such as nausea, bloating, and abdominal pain. While EIGS has been extensively studied in endurance athletes, its effects on rowers remain unclear. This study aims to evaluate markers of intestinal damage and increased gut permeability following a 6000-meter maximal rowing ergometer test, in order to determine whether prolonged exertion contributes to intestinal barrier disruption.
Methods: Twenty-one elite male rowers from the Polish National Team participated in this observational study. The athletes performed a 6000-meter maximal test on a rowing ergometer. Blood samples were collected at three time points: pre-exercise, immediately post-exercise, and one hour into recovery. Serum levels of intestinal permeability markers (I-FABP, CLDN-3) and endotoxemia markers (LPS, LBP) were analyzed using ELISA assays. Gastrointestinal symptoms were assessed using a standardized questionnaire.
Results: A significant increase in I-FABP levels was observed post-exercise (p=0.0023), indicating enterocyte damage. CLDN-3 levels significantly increased from resting to post-exercise (p=0.0112) and continued rising during recovery (p=0.0099). LPS levels exhibited an upward trend from post-exercise to recovery (p=0.0155), and LBP levels significantly increased from baseline to recovery (p=0.0011). Strong correlations were found between LPS and CLDN-3 (p<0.0001, r=0.431), LPS and I-FABP (p=0.002, r=0.381), and CLDN-3 and I-FABP (p=0.012, r=0.313).
Conclusion: The 6000-meter maximal rowing test led to significant increases in gut permeability and endotoxemia markers, suggesting prolonged high-intensity exercise compromises intestinal barrier function. These results may guide strategies to protect gut integrity in endurance rowing.
