EVALUATION OF ERYTHROPOIETIN IN ENDURANCE RUNNERS

To evaluate the role of erythropoietin (Epo) in the erythroid abnormal ities often found in athletes, Epo was evaluated by radioimmunoassay i n endurance runners (ER). In a first study, 46 experienced ER, 11 with iron deficiency (ID group), were studied during a training period. In ID and non-ID runners, serum Epo (SEpo) levels were similar to sedent ary controls (ID=19.1+/-4.9 U/L, non-ID=19.7+/-5.5 U/L and controls 19 .7+/-9.2 U/L). In a second study, serum and urine erythropoietin (UEpo ) levels were evaluated in 17 ER during a 6-hour race. Samples were ta ken before the race (pre-race), immediately following (6-hour) and 4 d ays after (post-race). No differences were observed in SEpo levels (pr e-race=19.8+/-4.1 U/L, 6-hour=21.2.+/-4.9 U/L and post-race =21+/-4 U/ L), but UEpo increased following the race (pre-race=15.4+/-9.6 U/L, 6- hour=26.1+/-6.2 U/L and post-race=14.1+/-6.5 U/L)(p<0.0001) and this U Epo increase was related to urine creatinine changes (rs=0.79, p<0.000 01). In conclusion, SEpo in ER does not differ from sedentary values a nd does not vary with competition; however, UEpo increases during a lo ng-distance race. These data may be important for a correct evaluation of Epo abusers and sports anemia.