A, IL-8 arterial plasma concentration before (0 h), during (0.5 and 1.5 h) and after 3 h of two-legged knee-extensor exercise, and 2 h (5 h) after the end of exercise. Values are means ± s.e.m. (n = 6). B, leg plasma femoral venous–arterial (fv–a) IL-8 difference before (0 h), during (0.5 and 1.5 h) and after 3 h of two-legged knee-extensor exercise, and 2 h (5 h) post exercise. Values are means ± s.e.m. (n = 6). *Significant difference (P < 0.05) from before (0 h). C, leg blood flow before (0 h), during (0.5 and 1.5 h) and after 3 h of two-legged knee-extensor exercise, and 2 h (5 h) after the end of exercise. Values are means ± s.e.m. (n = 6). *Significant difference (P < 0.05) from before (0 h). D, leg net IL-8 balance (ng min−1) values before (0 h), during (0.5 and 1.5 h) and after 3 h of two-legged knee-extensor exercise, and 2 h postexercise (5 h). Values are means ± s.e.m. (n = 6). *Significant difference (P < 0.05) from before (0 h).