NO EFFECT OF ENDURANCE EXERCISE ON SERUM BILIRUBIN IN HEALTHY ATHLETES AND WITH CONGENITAL HYPERBILIRUBINEMIA (GILBERTS-SYNDROME)

Twenty male athletes, mean age 26 years, were studied by a work load t est with cycle-ergometer, with increasing power output for 60 minutes until an intensity corresponding to 70% of the individual maximal hear t rate was achieved. Ten of them had familial hyperbilirubinemia (Gilb ert's syndrome) and ten had been considered as healthy controls. The d iagnosis of Gilbert's syndrome was made using the following criteria: unconjugated hyperbilirubinemia, no systemic symptoms, no overt or cli nically recognizable haemolysis, normal liver function tests. Blood le vels of free fatty acids (FFA) showed a progressive significant increa se after muscular exercise in both healthy and Gilbert's syndrome subj ects (p<0.001). The increase was more evident in controls compared to Gilbert's syndrome subjects (p<0.05). Total and fractionated bilirubin showed no change in both groups. In conclusion, a competitive mechani sm between bilirubin and FFA is probably responsible for the lower inc rease in plasma FFA in Gilbert's syndrome.