Muscle lactate metabolic recovery in sea bass juveniles was studied in respect to the water temperature. The fish used in this study were cultured with the semi-extensive mesocosm method, and the water temperatures were 15 and 20 degrees C. Fish were led to exhaustion by exercising in a swimming channel, and the muscle lactate levels were measured seven times before and after exercise. The results showed that muscle lactate concentration rises during exercise until it reaches a maximum (exhaustion point), and then it keeps falling during the recovery time. Also, fish exercised at 20 degrees C exhibited higher lactate values at the exhaustion point and faster decomposition rates during recovery.