Erythrocyte Adaptation to Oxidative Stress in Endurance Training

We tested the hypothesis that endurance training may reduce exercise oxidative stress damage on erythrocytes.Fifteen subjects performed a standardized endurance exercise at 75% of maximal oxygen consumption weekly during a 19-week training period. Blood samples taken before and after exercise were analyzed by Fourier transform-infrared (FT-IR) spectrometry to determine exercise-induced change in plasma concentrations and erythrocyte IR absorptions.Training first induced a stabilization of plasma concentration changes during exercise (unchanged for glucose, increased for lactate, triglycerides, glycerol, and fatty acids), whereas erythrocyte phospholipid alterations remained elevated (p0.05). Further, training reduced the exercise-induced erythrocyte lactate content increase (nuC-O; p0.05) and phospholipid alterations (nuC-H(n) and nuP=O; p0.05) during exercise. These changes paralleled the decrease of exercise-induced hemoconcentration (p0.05) and plasma lactate increase (p0.05).These correlated changes between plasma and erythrocyte parameters suggest that endurance training reduces erythrocyte susceptibility to oxidative stress.