Implementation and utility of an online psychological assessment tool in youth soccer players: a one-year longitudinal study

Most studies on digital tools for assessing psychological states in sports have focused on screening athletes who show pathological tendencies, while few have examined their potential use for team management or coaching strategies. Moreover, little evidence exists regarding long-term, voluntary use among youth athletes. This study introduced an online psychological assessment system into a youth sports team to examine the effectiveness of digital tools for monitoring athletes' psychological states, based on usage patterns and assessment results. Participants were 81 male soccer academy athletes aged 12-17 years. Analyses were conducted on annual participation frequency, overall score trends, intraindividual variability, and the relationships between motivation to continue participation and satisfaction measures. The athletes completed the assessments an average of 4.16 times over the year, but participation rates declined in the latter half of the period. The variance in relationship with coach and satisfaction with growth increased during the competitive season. Satisfaction with life and satisfaction with time in daily life showed large intraindividual fluctuations. Satisfaction with growth, relationship with coach, satisfaction with life, and satisfaction with time in daily life significantly influenced motivation to continue participation. These results indicate that psychological assessment tools may be useful for tracking seasonal changes in athletes' psychological states, enabling early detection of dissatisfaction or concerns beyond team activities, and guiding the prioritization of support to promote sustained sport participation. Digital tools enabling regular psychological monitoring can reduce respondent burden, complement coaches' expertise, and serve as effective resources for team management and mental health support.