The reliability, validity and sensitivity of a novel soccer-specific reactive repeated-sprint test (RRST).
OBJECTIVE
The aim of this study was to determine the reliability, validity and sensitivity of a reactive repeated-sprint test (RRST).


METHODS
Elite (n = 72) and sub-elite male (n = 87) and elite female soccer players (n = 12) completed the RRST at set times during a season. Total distance timed was 30 m and the RRST performance measure was the total time (s) across eight repetitions. Competitive match running performance was measured using GPS and high-intensity running quantified (≥ 19.8 km h(-1)).


RESULTS
Test-retest coefficient of variation in elite U16 and sub-elite U19 players was 0.71 and 0.84 %, respectively. Elite U18 players' RRST performances were better (P < 0.01) than elite U16, sub-elite U16, U18, U19 and elite senior female players (58.25 ± 1.34 vs 59.97 ± 1.64, 61.42 ± 2.25, 61.66 ± 1.70, 61.02 ± 2.31 and 63.88 ± 1.46 s; ES 0.6-1.9). For elite U18 players, RRST performances for central defenders (59.84 ± 1.35 s) were lower (P < 0.05) than full backs (57.85 ± 0.77 s), but not attackers (58.17 ± 1.73 s) or central and wide midfielders (58.55 ± 1.08 and 58.58 ± 1.89 s; ES 0.7-1.4). Elite U16 players demonstrated lower (P < 0.01) RRST performances during the preparation period versus the start, middle and end of season periods (61.13 ± 1.53 vs 59.51 ± 1.39, 59.25 ± 1.42 and 59.20 ± 1.57 s; ES 1.0-1.1). Very large magnitude correlations (P < 0.01) were observed between RRST performance and high-intensity running in the most intense 5-min period of a match for both elite and sub-elite U18 players (r = -0.71 and -0.74), with the best time of the RRST also correlating with the arrowhead agility test for elite U16 and U18 players (r = 0.84 and 0.75).


CONCLUSIONS
The data demonstrate that the RRST is a reliable and valid test that distinguishes between performance across standard, position and seasonal period.
Department of Sport and Exercise Sciences, University of Sunderland, Sunderland, UK.
Michele
M
Di Mascio
Department of Sport and Exercise Sciences, University of Sunderland, Sunderland, UK.|Medical Department, Newcastle United Football Club, Newcastle upon Tyne, UK.
Jack
J
Ade
Carnegie School of Sport, Leeds Beckett University, Leeds, UK. paulbradley94@yahoo.co.uk.
Paul S
PS
Bradley
D000293:Adolescent; D000328:Adult; D056352:Athletes; D054874:Athletic Performance; D005260:Female; D006801:Humans; D008297:Male; D012680:Sensitivity and Specificity; D012916:Soccer / Q000502:physiology*
Fitness testing; Football; High-intensity; Intense periods