Chronic administration of β-alanine has been shown to increase muscle carnosine content and improve anaerobic performance. It is not clear whether acute ingestion of carnosine and beta alanine may have the same effects. With a view to investigating acute effects of carnosine and β-alanine ingestion on anaerobic intermittent running performance and on the responses of Interleukin-6 and -10 to exercise, twelve healthy, young, active participants (age: 21 ± 4 years) underwent the running-based anaerobic test (RAST) twice (with 30 min recovery in between) on two separate occasions (randomized, crossover design). The test consisted of 6 × 35-m sprints interspersed with 10 s rests after acute ingestion (4 hours before the test) of either 2 g L-carnosine + 2 g β-alanine or placebo. The overall performance decreased (RAST1 vs RAST2, carnosine + β-alanine: 32.8 ± 1.3 s, 33.4 ± 1.2 s; Placebo: 32.9 ± 1.0 s, 33.6 ± 1.2 s), pain after RASTs increased (RAST1 vs RAST2, carnosine + β-alanine: 3.0 ± 2.1 a.u., 4.2 ± 1.9 a.u.; Placebo: 3.0 ± 1.8 a.u., 3.4 ± 1.2 a.u.) almost in the same way in both groups, and RPE did not show any difference. IL6 and IL10 gene expression increased and decreased respectively in response to exercise in the same fashion in both conditions. During RAST 2 we found a potentially increased performance in the carnosine + β-alanine group (main effect of condition, p