Many adolescent sport activities can be classified as anaerobic in nature. A reliable method to assess fatigue associated with this type of exercise is necessary with regard to investigating performance decrements. PURPOSE: This study evaluated performance and fatigability utilizing intermittent high-intensity cycling sprints and the Wingate Anaerobic Test (WAnT). METHODS: Six healthy males (15.9 ± 0.8 yrs) voluntarily completed two exercise trials consisting of a WAnT bout followed by ten 10-second sprints and a second WAnT bout; 30 seconds of rest was allotted between exercise intervals. Exercise trials were separated by at least 48 hours and matched for time of day. Peak power (PP) and mean power (MP) were measured during each WAnT. Average PP (avgPP) and average MP (avgMP) were measured during the ten sprint bouts. WAnT data were analyzed with a two-way (trial x time) ANOVA. A student's T-test was used to compare avgPP and avgMP. An intraclass correlation was used to assess reliability. RESULTS: Across time, PP averaged 432.6 ±42.8 W and 296.6 ± 35.7 W in the first trial and 423.0 ±62.0 and 312.8 ± 59.6 Win the second trial (p < 0.05). There were no trial or interaction effects. MP was 332.5 ± 32.8 W and 216.0 ± 16.3W and 326.3 ±33.9 W and 230.2 ± 19.6 W in trials one and two, respectively. The decrease over time was significant, but the trial and interaction effects were not. AvgPP (325.2 ± 44.2 and 325.7 ± 25.5 W) and avgMP (269.6 ± 35.7 W and 272.7 ± 28.7 W) for the first and second exercise trials were similar (p > 0.05). Intra-class correlation coefficients ranged from 0.58-0.93; and were significant, except for PP in the second WAnT (p = 0.09). CONCLUSIONS: Use often 10-second cycling sprints between two WAnT bouts appears to yield repeatable performance outcomes. Furthermore, sufficient fatigue was elicited in WAnT performance with adolescent males. The ability to quantify muscle fatigue responses in a reliable manner is necessary for accurate performance assessment. Funding provided by: Gatorade Sports Science Institute, Barrington, IL