The purpose of the study was to reexamine the relationship between the Wingate and Critical Power tests of anaerobic capacity (AC) and anaerobic reserve (AR), respectively. A second purpose was to observe gender differences. Both tests were administered to 16 female and 13 male subjects(N = 29) on a Monark cycle ergometer with six subjects repeating AR measurement. The results show that AC (240.2 ± 30.5 J·kg-1, calculated from total work for 30 s) and AR (184.0± 1.2 J·kg-1) were not well-correlated (r = 0.07,P > 0.72). When expressed as total energy independent of body mass, the relationship was significant but low (r = 0.41, P > 0.02). Since AR was 23% lower than AC, which is believed to underestimate true anaerobic capacity, the data suggest that the Critical Power and Wingate tests do not assess the same anaerobic compartments. AR from the Critical Power test may not include the energy component of anaerobic glycolysis. Therefore, intrinsic methodological and theoretical differences between the tests make the absolute comparison of AC and AR problematic.