The purpose of this study was to investigate the influence of glycogen stores on the maximal responses of IL-1beta, IL-6, and IL-10 to a discontinuous, progressive cycle ergometry test. Eight trained cyclists completed two progressive maximal cycle ergometry tests (5 min stages with 5 min recovery), one normally fed and one following glycogen-depletion (2-h at 60-65% VO2max). Percent changes in circulating IL-1beta, IL-6, and IL-10 were measured during exercise and recovery and peak changes were compared. IL-6 showed a trend towards significant interaction effect of exercise time and trial condition (p = 0.054) in both trials, but there were no significant differences among percent changes in IL-1beta or IL-10. Glycogen-reduction appeared to cause all cytokines to peak earlier, but the trend was not significant.