Mental fatigue in elite hockey match play and its relationship with internal load, external load and recovery

Introduction Elite athletes may encounter the challenge of sustained mental fatigue (MF) during competitions, which could have cumulative effects. However, current research on this issue is insufficient. The sustained MF experienced by elite athletes during competition differs from the acute MF typically examined in laboratory settings. Investigating this phenomenon and identifying influencing factors is crucial for enhancing practical sports performance. Method The study involved 17 elite athletes from the Chinese men's hockey team. The 23-day schedule was divided into four rounds: two warm-up and two formal competition rounds, categorize into match days (MD), technical days (TD) and recovery days (RD). The Firstbeat heart rate monitor was used to track load and recovery data. Athletes reported daily MF using a visual analogue scale and completed ratings of perception (RPE). The analysis examined variations in these indicators across rounds and days and explored the correlation between MF and other variables. Result The data analysis results for different rounds showed no significant within-timepoint differences in MF (P = 0.433). However, there were only highly significant differences in MF between different days within Round 3 (P = 0.000) and Round 4 (P = 0.008). Correlation analysis of summary data showed that MF significantly associated with increased HRr (P < 0.001, r = 0.250). In addition, MF significantly associated with reduced RPE (P < 0.001, r = − 0.187), HRVr (P < 0.01, r = − 0.141) and HRVm (P < 0.05, r = − 0.127). Discussion This study suggests that MF during competitions exerts short-term and day-specific fluctuations. Notably, MF was generally lower in match rounds than warm-up rounds. Furthermore, actual competition contexts revealed that the perceived importance of a competition has a negative correlation with intraday MF, suggesting the athletes' self-regulation and willingness to win were influential factors. The study found that elite athletes maintained stable recovery status during match rounds, likely due to their extensive training, which helped them adapt to physical and psychological demands. Overall, this study contributes evidence supporting short-term and day-specific fluctuations in MF, revealing that MF of elite hockey players is related to match load and recovery status.