Correlation between sleep and psychological mood states in female wheelchair basketball players on a Japanese national team

[Purpose] Although some studies suggest the importance of getting adequate sleep for enhancing mood, there is not yet sufficient evidence on the relationship between sleep and mood states in athletes, especially for athletes with physical disability. The purpose of this study is to reveal relationships between sleep and psychological mood states in female wheelchair basketball players. [Subjects and Methods] Seventeen female wheelchair basketball players (30.9 ± 9.4 years old) on a Japanese national team participated. Sleep states were assessed with the Pittsburgh Sleep Quality Index (PSQI), and mood states with the Japanese version of the Profile of Mood States short form (POMS-SF). Spearman's rank correlations were computed. [Results] The mean PSQI score was 5.4 ± 2.6 points, and 9 athletes (52.9%) exceeded the cutoff point (5.5) for insomnia. Higher sleep efficiency (rS=0.58), fewer sleep disturbances (rS=-0.58), and lower total PSQI score (rS=-0.51) were significantly correlated with higher vigor. Lower likelihood of daytime dysfunction was also significantly correlated with lower tension (rS=0.50). [Conclusion] Vigor was the mood state most frequently correlated with sleep variables. Because vigor is a known key psychological factor in optimal performance, the findings are valuable for wheelchair basketball players.