Evaluation of Mental Workload for Athletes´ Training Based on Salivary NO3- Concentration

We think that salivary NO₃^- concentration corresponds to mental workload. To confirm that, so far we have a lot of experiments for navigators in handling-a-ship simulator, which can be arranged an experiment´s surroundings. Through this experiment, we trust in the effectiveness of salivary NO₃^- concentration as a physiological index, because the salivary NO₃^- has a special characteristic to show quick response to mental workload on the spot and such trend as moving average. On the other hand, we confirm the effectiveness of a variety of physiological indices, heart rate variability (R-R interval), nasal temperature, and salivary amylase as well as salivary NO₃^- concentration, but these are not good at giving us a response of mental workload instantly because these physiological indices need to analyse numerical values from data. After all, to evaluate mental workload quantitatively by salivary NO₃^- concentration helps younger navigators to grasp the handling-a-ship skill of veteran navigators, in concrete terms younger navigators understand the risky handling-a-ship situations from mental workload veteran navigators feel. As mentioned earlier, salivary NO₃^- concentration is a good index to measure mental workload, however, actually measurement errors by this index occur in experiments. So in this paper, we confirm one of the errors, occurred by exercise, and can decrease the error.