Figure 1. Vitamin C in serum, GSSG·GSH-1 ratio in blood and in RBCs during the ski marathon (x ± SD). Note. pre-COMP - precompetition level; post-COMP - immediately after the competition; RECOV - 18-hour recovery period; * p < 0.05, different from pre-COMP; # p < 0.05, different from post-COMP.