Introduction: The purpose of this study was to examine the effect of progressive fatigue from continuous workouts on Session Rating of Perceived Exertion (sRPE). Methods: Twelve moderately fit college age students who were active for the past three months for at least three times a week for 30-minutes or more were recruited. Subjects performed a maximal incremental cycling test to determine max power output (MPO). Subjects completed workouts on the bike at varying percentages of their MPO to test the hypothesis that sRPE for a given exercise bout would change with progressive fatigue. The workouts were Monday through Thursday for two weeks. The first week was three 30-minute sessions followed by a 1-hour session. The second week was three 1-hour sessions followed by a 30-minute session. Blood lactate was measured periodically throughout each workout. sRPE was measured 30 minutes after each session. Results: The 30-minute sessions had a sRPE that was significantly less than the 1-hour sessions (p = .006). The analysis of HLa during the hard sessions showed significant differences between sessions (p = .002). The analysis of the RPE/HLa ratio showed significant differences between sessions (p = .003). Discussion: The results of this study supported our hypothesis. During the prolonged exercise bouts, there was a significant decrease in HLa and a progressive increase in sRPE.