Reliability and validity of Yo-Yo tests in 9- to 16-year-old football players and matched non-sports active schoolboys

Abstract

The purpose of this study was to examine the test–retest reliability and construct validity of three age-adapted Yo-Yo intermittent tests in football players aged 9–16 years (n = 70) and in age-matched non-sports active boys (n = 72). Within 7 days, each participant performed two repetitions of an age-related intensity-adapted Yo-Yo intermittent test, i.e. the Yo-Yo intermittent recovery level 1 children's test for 9- to 11-year-olds; the Yo-Yo intermittent endurance level 1 for 12- to 13-year-olds and the Yo-Yo intermittent endurance level 2 test for 14- to 16-year-olds. Peak heart rate (HR_peak) was determined for all tests. The distance covered in the tests was 57% (1098 ± 680 vs. 700 ± 272 m), 119% (2325 ± 778 vs. 1062 ± 285 m) and 238% (1743 ± 460 vs. 515 ± 113 m) higher (p ≤ .016), respectively for football-trained than for non-sports active boys aged 9–11, 12–13 and 14–16 years. The typical errors of measurement for Yo-Yo distance, expressed as a percentage of the coefficient of variation (confidence interval), were 11.1% (9.0–14.7%), 10.1% (8.1–13.7%) and 8.5% (6.7–11.7%) for football players aged 9–11, 12–13 and 14–16 years, respectively, with corresponding values of 9.3% (7.4–12.8%), 10.2% (8.1–14.0%) and 8.5% (6.8–11.3%) for non-sports active boys. Intraclass correlation coefficient values for test–retest were excellent in both groups (range: 0.844–0.981). Relative HR_peak did not differ significantly between the groups in test and retest. In conclusion, Yo-Yo intermittent test performances and HR_peak are reliable for 9- to 16-year-old footballers and non-sports active boys. Additionally, performances of the three Yo-Yo tests were seemingly better for football-trained than for non-sports active boys, providing evidence of construct validity.

Keywords:

• Reliability
• heart rate
• intense intermittent exercise
• HIIT
• youth football
• aerobic endurance

Acknowledgements

The authors gratefully acknowledge the help and support of all the students who participated in the data collection from the undergraduate course in Physical Education and Sport and master's courses on Physical Education and Sport Sciences, Specialization in Sports Training and in The Teaching of Physical Education in Basic and Secondary Education at University Institute of Maia – Ismai. We also thank Dr. Luke Connolly for editing the manuscript.

Disclosure statement

No potential conflict of interest was reported by the authors.