Ce mois-ci, une nouvelle publication (sous presse) conduite par un étudiant australien en PhD, Pete Peeling, vous est proposée au regard de son intérêt majeur dans la problématique en course à pied des effets combinés de l'intensité de l'entraînement et de la surface de course sur les processus inflammatoire, hématologique :
Med Sci Sports Exerc. 2009
Training Surface and Intensity: Inflammation, Hemolysis, and Hepcidin Expression.
Peeling P, Dawson B, Goodman C, Landers G, Wiegerinck ET, Swinkels DW, Trinder D.
PURPOSE:: This investigation assessed the effects of training intensity and ground surface type on hemolysis, inflammation, and hepcidin activity during running.
METHODS:: Ten highly trained male endurance athletes completed a graded exercise test, two continuous 10-km runs on a grass (GRASS) and a bitumen road surface (ROAD) at 75%-80% peak V(dot)O2 running velocity, and a 10 x 1 km interval running session (INT) at 90%-95% of the peak V(dot)O2 running velocity. Venous blood and urine samples were collected before, immediately after, and at 3 and 24 h after exercise. Serum samples were analyzed for circulating levels of IL-6, free hemoglobin (Hb), haptoglobin (Hp), iron, and ferritin. Urine samples were analyzed for changes in hepcidin expression.
RESULTS:: After running, the IL-6 and free Hb were significantly greater, and serum Hp was significantly lower than preexercise values in all three conditions (P < 0.05). Furthermore, IL-6
levels and the change in free Hb from baseline were significantly greater in the INT compared with those in the GRASS (P < 0.05). There were no differences between the GRASS and ROAD training surfaces (P > 0.05). Serum iron and ferritin were significantly increased after exercise in all three conditions (P < 0.05) but were not different between trials.
CONCLUSION:: Greater running intensities incur more inflammation and hemolysis, but these variables were not affected by the surface type trained upon.