explain referees are essential factor of sports match
Answers
Explanation:
Abstract
The evaluation of match officials’ neuromuscular performance is now an important consideration and the vertical jump test is considered suitable for assessing lower limb power, partly because it is directly related to refereeing. The aim of this study, therefore, was to determine the effect of soccer matches on match officials’ vertical jump performance by assessing various biomechanical variables. Eighteen field referees (FRs) and 36 assistant referees (ARs) who officiated in 18 official matches participated in this study. Before the match, at half time and immediately after the match, officials performed two countermovement jumps. Flight phase time (FT), maximum force production (MFpropulsion), time to production of maximum force (TMFpropulsion), production of maximum power (MP), maximum landing force (MFlanding) and time to stabilization (TTS) were calculated for all jumps. There was a tendency for match officials’ jumping performance to improve after matches than beforehand (FR: effect size (ES) = 0.19 ± 0.36, possibly trivial; AR: ES = 0.07 ± 0.17, likely trivial). There were also likely small and very likely moderate differences between FRs’ MP in pre-match and half-time jumps (ES = 0.46 ± 0.47) and in their pre- and post-match jumps (ES = 0.71 ± 0.48). These results indicate that refereeing soccer matches does not reduce vertical jump performance; the subsequent neuromuscular fatigue is not sufficient to affect landing technique.
Key words: strength, biomechanics, competition, fatigue
Introduction
Refereeing soccer matches is a very physically demanding task for field referees (FRs) and assistant referees (ARs). FRs have been shown to cover approximately 10–12 km during the course of matches with a mean heart rate (HRmean) of 86% of their maximum heart rate (HRmax) (Mallo et al., 2009a) with 34% of the total distance being covered during high-intensity running (>13 km·h-1) (Mallo et al., 2009a). The physical demands of soccer matches on FRs have been shown to be similar to, or even higher than the demands on players (Weston et al., 2007). ARs, however, have been shown to run 5–6 km during soccer matches with almost 20% of this distance being covered during high-intensity running (Krustrup et al., 2009) and a HRmean of 77% of their HRmax (Mallo et al., 2009b).
A number of studies have shown that match officials perform a considerable amount of high-intensity running (Weston, 2014) and it is possible that they may experience fatigue during matches as a consequence. Fatigue has been shown to have a detrimental effect on physical performance (Weston, 2014): distance covered at high-intensity running and total distance covered were shorter during examined 15 min periods of the second half than in the first 15 min period of the first half. Accumulated match-related fatigue is determined by several factors, including running performance during the match (Weston et al., 2012), thus, in order to track development of fatigue directly, it is necessary to combine assessments of match running performance and the physiological impact of the match with performance tests before and after games (Krustrup et al., 2010). Although it is difficult to discern from match analysis data (Weston et al., 2012), some authors have attempted to infer how matches affect players’ (Cortis et al., 2013; Povoas et al., 2014) and FRs’ (Tessitore et al., 2007) fatigue levels from data on match-induced changes in vertical jump and sprint performance. However, to our knowledge only one study has investigated how soccer matches affect the physical performance of both FRs and ARs (Castillo et al., 2016).