Evaluation of a goalkeeper-specific adaptation to the Yo-Yo intermittent recovery test level 1: Reliability and variability

The Yo-Yo Intermittent Recovery Test Level 1 (YYIR1) has been shown to be a reliable test with strong correlations to physical match performance in field soccer players. However, the YYIR1 has less goalkeeper (GK) specificity. Therefore, the purpose of this study was to evaluate the test-retest reliability of a goalkeeper-specific adaptation of the YYIR1 (YYIR1-GK). Sixteen National Collegiate Athletic Association (NCAA) collegiate GKs (8 men and 8 women) performed the YYIR1-GK test twice (>4 and <7 days apart) to determine its reliability and variability. Subjects were tested at the same time of day and in a controlled indoor environment. Heart rate using polar monitors and rating of perceived exertion were obtained at the end of each stage of the YYIR1-GK. Test-retest reliability for each test was assessed by Pearson correlations, intraclass correlation coefficient (ICC), and coefficient of variation (CV). The YYIR1-GK was shown to have a strong test-retest reliability and low variability for male (r = 0.981, ICC = 0.980, CV = 5.82%) and female (r = 0.969, ICC = 0.956, CV = 9.60%) NCAA GKs, respectively. Male GKs performed significantly more stages and therein covered a greater distance in the YYIR1-GK than the female GKs (p = 0.05). This study suggests that the YYIR1-GK is a consistent assessment of intermittent fitness with high test-retest reliability and low variability in male and female NCAA GKs. It is suggested that larger numbers of GKs of various skill levels be evaluated in the future