To compare the physiological stress (AUCg values) between the different situations analyzed (resting, training, and matches), a two way repeated measures ANOVA and Tukey test were used.
To analyze the physiological stress, the resting situations (C1, C2, and C3), training (C4 to C9), and match (C10, C11, and C12) were used to calculate the area under the curve in relation to zero (AUCg) using the trapezoid formula.
Figure 1 shows the average values of AUCg for cortisol concentrations found in soccer athletes Under-17 in the 5 situations evaluated in this study (resting, during training 1, 2, and 3, and during the match).
This was done to compare the psychological stress with the athlete's physiological stress (i.e., data obtained by calculating AUCg for concentrations of cortisol) during two training situations.
It was found a positive correlation (P = 0.037) only between the amount of cortisol (AUCg) and the scale of General Recovery in Training 1.
Significant differences in the values of AUCg were found between resting and training situations (1, 2, 3) as well as between trainings (1, 2, 3) and the match.
(36) who found significant differences in the values of AUCg between resting situation and the competitive situation.
Correlation between the Current State of Stress and Recovery (RESTQ-76-Sport) and the Current State of Physiological Stress (values of AUCg) in Situations of Training and Matches
Interestingly, in the present study, the correlation was found only between the scale of General Recovery RESTQ-76-Sport and AUCg value (related to the concentration of salivary cortisol) in Training 1.
The analysis of physiological levels of stress presented by the athletes in those different moments evaluated (resting, training and competition) demonstrates significant differences between the values of AUCg for the most of the situations analyzed (i.e., between resting and training and between training and matches).