Inflammation, muscle damage and post-race physical activity following a mountain ultramarathon.

BACKGROUND The study aimed at exploring whether muscle membrane disruption, as a surrogate for muscle damage, and inflammation recovery following a mountain ultramarathon (MUM) was related with race performance and post-race physical activity. METHODS Blood samples were obtained from thirty-four athletes (29 men and 5 women) before a 118-km MUM, immediately after and three and seven days post-race. Creatine kinase (CK), lactate dehydrogenase (LDH) and C-reactive protein (CRP) were compared between faster (FR) and slower (SR) runners. Physical activity performed during the week following the MUM was objectively analyzed using accelerometers and compared between FR and SR. RESULTS CK was significantly higher in FR at 3 days post-race (p<0.012, d=1.17) and LDH was significantly higher in FR at 3 and 7 days post-race (p=0.005, d=1.01; p<0.015, d=1.05 respectively), as compared to SR. No significant differences were identified in post-race physical activity levels between FR and SR. Significant relationships were found between race time and CK and LDH concentrations at 3 days post-race (rs=-0.41, p=0.017; rs=-0.52, p=0.002 respectively) and 7 days post-race (rs=-0.36, p=0.039; rs=-0.46. p=0.007 respectively). However, post-race physical activity was not associated with muscle damage and inflammation recovery, except for light intensity and CRP at 3 days post-race (rs=-0.40, p=0.025). CONCLUSIONS Race time appeared to have a higher influence on muscle damage recovery than the intensity of physical activities performed in the week after running a MUM. Inflammatory activity takes longer to normalize than muscle damage following a MUM, it is not related with race time and lightly related with post-race physical activity.