Comparing the Yo-Yo intermittent and Bronco tests and their associations with match demands among amateur rugby union referees

This study compared the Yo-Yo intermittent recovery level 1 (YYIR ₁) and Bronco tests among amateur rugby referees and examined whether the results of these tests were associated with actual match demands. Sixty-seven (65 male, 2 female; 30 ± 11 years; 77.4 ± 13.1 kg; 175 ± 8 cm) amateur rugby referees participated. Match demands were assessed using Global Navigation Satellite System technology and heart rate (HR) recordings. Significant correlations (all p < 0.05) were found between the YYIR ₁ and Bronco test results (r: −0.88). The YYIR ₁ test was significantly correlated with match demands including total (r: 0.56) and high-intensity (r: 0.70) distance covered, maximal speed reached (r: 0.73), and the number of high-intensity accelerations (r: 0.54) and sprints (r: 0.68) completed. Furthermore, YYIR ₁ test maximum HR was significantly correlated with maximum HR (r: 0.72), average HR (r: 0.54), and internal load (r: 0.55) during match play. In contrast, the Bronco test was only significantly correlated with match demands including maximal speed reached (r: −0.68) and the number of high-intensity accelerations (r: −0.61). Moreover, Bronco test maximum HR was significantly correlated with maximal (r: 0.84) and average HR (r: 0.73) during match play. The results suggest that while the YYIR ₁ and Bronco tests might both be efficient tools to guide training prescription, the YYIR ₁ test might be as the more valuable test to assess match fitness in rugby referees.