3.3. Subjective stress
Psychosocial stress was evaluated by each participant at the end of daily practice using VAS
(0–10). The average score was significantly lower in the theanine-group than in the placebo-group (p = 0.020;one-way ANOVA; Table 1), which trait is notable from the first day of pharmacy practice (Fig. 4).A positive correlation between subjective stress and post-practice sAA was observed both in the theanine-group (R = 0.771, p = 0.0090;Fig. 5b) and in the placebo-group (R = 0.582, p = 0.077: Fig. 5a). The correlation coefficients were not significantly different (p N 0.05, Fisher's z-test). Next, the participants were divided into three grades based on
the subjective stress score (low: 0–3.4, middle: 3.5–6.4, and high: 6.5–10). The participants with low subjective stress exhibited significantly lower post-practice sAA in the theanine-group than in the placebogroup (p = 0.0023; one-way ANOVA; Table 2). No theanine-group participants showed high subjective stress. A close relationship between subjective stress and STAI was observed in theanine-group (R = 0.866 and p = 0.0012; Fig. 5d) but not in placebo-group (Fig. 5c).