Effect of marathon and ultra‐marathon on inflammation and iron homeostasis

The physiological response to high‐level endurance exercise, such as running a marathon, poses several beneficial but also potentially harmful metabolic changes. The objective of this study was to determine the impact of marathon (M) and ultra‐marathon (UM) on inflammation and iron homeostasis in paired samples. Fifteen well‐trained, non‐professional endurance athletes (14 males, 1 female) performed both a 130 km ultra‐marathon and a traditional 42.195 km marathon. We determined markers of inflammation and iron homeostasis before, immediately after, and within 5 days after finishing each run, respectively. Biomarkers of inflammation (leucocytes, neutrophil granulocytes, monocytes, and c‐reactive protein [CRP]) increased significantly after both marathon and ultra‐marathon with higher levels of CRP after ultra‐marathon compared with marathon both immediately after the race (18.15 ± 12.41 vs 5.58 ± 9.65 mg/L, P