Evaluation of the reliability of a goalkeeper-specific adaptation to the Yo Yo Intermittent Recovery Test Level 1

The evaluation of physical fitness is important for top soccer clubs in order to guide training programs and match preparation. Field tests are commonly used by coaches and training staff as they are more convenient and require less equipment than laboratory testing. The most commonly utilized and studied field test for soccer fitness is the Yo-Yo Intermittent Recovery Test Level 1 (YYIR1). Studies have shown strong correlations between YYIR1 results and distance covered at high intensity running speeds during match play, an important measure of physical performance (Rampinini et al., 2007; Krustrup et al., 2005). The YYIR1 has also been able to differentiate between skill levels and shown a gender difference similar to that seen in actual match play (Krustrup et al., 2003). The goalkeeper is an important position to match outcome but has been largely neglected in exercise science research. Current literature has shown only a handful of attempts at goalkeeper-specific tests, with most of them focused more on cognitive, reactive, or technical factors rather than evaluating the ability to meet the physical demands of the position (Knoop, Fernandez, & Ferruati, 2013). In addition, there have been few studies to include female goalkeepers. As the YYIR1 is the most popular and validated fitness test for soccer players, establishing a goalkeeper-specific adaptation to the test (YYIR1-GK) could benefit coaches and training staff in terms of guiding fitness programs and optimizing match and seasonal preparation.The primary objectives of this study were 1) to evaluate the test-retest reliability of the YYIR1-GK in both male and female collegiate soccer goalkeepers, 2) to determine whether performance on the YYIR1-GK correlates with performance on a validated cycling test of repeated sprint ability, and 3) to analyze group differences in performance on both tests in terms of gender. To accomplish these objectives, male and female NCAA goalkeepers were recruited for two identical visits exactly one week apart during which they completed both the YYIR1-GK and the 5x6 Second RSA Cycle Test.Upon analysis, the YYIR1-GK exhibited strong test-retest reliability as measured by Intraclass Correlation Coefficient, Pearson Product-Moment Correlation Coefficient, and Coefficient of Variation. The reliability outcomes are similar to those reported in past studies with the standard YYIR1. Additionally, the 5x6 Sec RSA Cycle test showed moderate to strong test-retest reliability in several outcome measures such as total power and work as well as peak sprint performance. There were no significant correlations between performance on the YYIR1-GK and the 5x6 Sec RSA Cycle test. There were however significant gender differences in performance on both tests, with men completing more stages on the YYIR1-GK and having higher outcomes for multiple measures of power and work on the cycle test. Overall, the results of this study would indicate that the YYIR1-GK is a reliable measure of intermittent fitness in collegiate soccer goalkeepers