Muscle damage and inflammation biomarkers after two ultra-endurance mountain races of different distances: 54 km vs 111 km

The aims of this study were 1) to describe the effects of a 54 km and 111 km ultra-endurance mountain race on the biomarkers of muscle damage and inflammation, 2) to compare the effects between the two races regarding the biomarkers of muscle damage and inflammation.Sixteen ultra-endurance amateur runners volunteered to participate in this study. Ten runners completed a 54 km race (Group 1; age: 27.0 ± 5.7; height: 179.5 ± 5.8 cm; and body mass: 77.3 ± 10.7 kg) and six completed a 111 km race (Group 2; age: 30.5 ± 8.0; height: 179.4 ± 5.5 cm; and body mass: 76.2 ± 9.4 kg). Blood samples were taken at five different points during the investigation, 24 h before the race, immediately post-race, and again at 24, 48, and 72 h after the race.There were increases in leukocyte (Group 1: p ≤ .001, ES = 2.8; Group 2: p = .001, ES = 3.5) and platelet concentrations (Group 1: p ≤ .001, ES = 2.3; Group 2: p = .02, ES = 1.7) post-races. Significant inter-race differences were also observed in leukocyte at 72 h (Group 1: 5.5 ± 0.9, Group 2: 4.2 ± 0.9, p = .012, ES = 1.5). Erythrocytes, hematocrit and hemoglobin concentration decreased after 54 km and 111 km races at 24, 48 and 72 h (p ≤.001, ES = 2.0–3.18). Serum uric acid concentration increased after the 54 km race (pre = 4.9 ± 1.2 – post = 7.3 ± 1.0 8 mg/dl; p ≤ .001, ES = 2.4), and also the 111 km race (pre = 5.3 ± 0.9 – post = 6.7 ± 0.8 mg/dl; p < .008, ES = 2.2). GPT, GOT and LDH had changed by the end of the races (p < .05) and differences between the groups were observed in GOT post-race (p = .008, ES = 1.7) 24 h (p = .004, ES = 1.8), 48 h (p = .007, ES = 1.6), and 72 h (p = .02, ES = 1.4) and also in LDH at 24, 48, 72 h. Serum creatinine decreased post-race in Group 1 (pre = 1.1 ± 0.1 – post = 1.4 ± 0.2 mg/dl; p = .001, ES = 1.5) and Group 2 (pre = 1.2 ± 0.1, post = 1.5 ± 0.2; p = .002, ES = 3.3) along with CK and myoglobin. In addition, values did not return to baseline levels after 72 h in Group 2 for C-reactive protein, myoglobin, and CK. Differences between the races were also observed post-race in Troponin I (Group 1 = 0.06 ± 0.05, 111 km = 0.02 ± 0.01 μg/l, p = .047, ES = 1.1) and C-reactive protein post-race (Group 2 = 2.5 ± 1.6, 111 km = 18.2 ± 6.4 mg/l, p ≤ .001, ES = 4.4) at 24 and 48 h.The athletes had increased concentrations of markers associated with damage, inflammation, muscle injury and cardiac damage after the races. Furthermore, athletes who completed the greater distance (111 km) had higher concentrations of the markers associated with muscle damage and muscle inflammation which remained changed for a period of 72 h. However, the participants of the ‘shorter race’ showed higher values associated with cardiac damage. Consequently, athletes who take part in these kinds of races should wait at least 72 h before training with high load.