Daniel Castillo

The influence of soccer match play on physiological and physical performance measures in soccer referees and assistant referees

ABSTRACT The aim of this study was to quantify the acute impact of soccer match officiating on selected physiological and physical performance measures. Twenty-four officials from the Spanish National 3rd Division participated in this study. External global positioning system and internal (heart rate) load data were collected for each match official during 8 official matches. Pre- and post-matches, the referees were assessed for tympanic temperature, blood lactate, 15- and 30-m sprint speeds and unilateral (dominant and non-dominant legs) and bilateral vertical jump performances. For referees, the acute physiological and physical performance effects of officiating (post-match value minus pre-match value) were large increases in blood lactate (1.7 mmol · l−1; ±90% confidence limit, 0.9 mmol · l−1; effect size, ES = 4.35), small increases in 15-m sprint (0.09; ±0.04 s; ES = 0.53) and 30-m sprint speeds (0.14; ±0.08 s; ES = 0.39) and a small increase in non-dominant leg jump performance (2.1; ±1.4 cm; ES = 0.31). For assistant referees, there was a small decrease in tympanic temperature (−0.3°C; ±0.2°C; ES = −0.65) and small increases in blood lactate (0.4; ±0.3 mmol · l−1; ES = 0.66), 15-m sprint speed (0.06; ±0.04 s; ES = 0.47), 30-m sprint speed (0.11; ±0.16 s; ES = 0.49) and bilateral countermovement jump height (3.4; ±1.5 cm; ES = 0.45). Taken together, these data demonstrate that the physical demands of soccer officiating are sufficient to elicit increases in blood lactate and small decrements in sprint performance and, thereby, provide some evidence for match-related fatigue.

Effects of horizontal plyometric training volume on soccer players’ performance

ABSTRACT The aim of this study was to examine the dose response effect of strength and conditioning programmes, involving horizontally oriented plyometric exercises, on relevant soccer performance variables. Sixteen soccer players were randomly allocated to two 6-week plyometric training groups (G1 and G2) differing by imposed (twice a week) training volume. Post-training G1 (4.13%; d = 0.43) and G2 (2.45%; d = 0.53) moderately improved their horizontal countermovement jump performance. Significant between-group differences (p < 0.01) in the vertical countermovement jump for force production time (T2) were detected post-training. No significant and practical (p > 0.05, d = trivial or small) post-training improvements in sprint, change of direction ability (CODA) and horizontal arm swing countermovement jump were reported in either group. Horizontal plyometric training was effective in promoting improvement in injury prevention variables. Doubling the volume of a horizontal plyometric training protocol was shown to have no additional effect over functional aspects of soccer players’ performance.

Influence of warm-up duration on physical performance and psychological perceptions in handball players

ABSTRACT The purpose of the study was to analyse the effect of two warm-up protocols of different duration on physical performance, perceived load and perception of being ready for a match in handball players. Eighteen handball players were randomly divided into two groups (Wup34min, warm-up protocol of 34 min, Wup17min, warm-up protocol of 17 min). Before and after the warm-up protocols, they performed a battery of physical tests and recorded their perception of feeling ready for a match. At the end of the warm-up protocols, all the players evaluated their differentiated perceived effort (dRPE). The results showed that neither of the protocols significantly modified (p > 0.05) the players’ physical performance. However, the Wup34min group showed higher values in the differentiated warm-up perceived load (dRPE-WL) (p < 0.01, TE = 0.97–1.27, high) than the Wup17min group. The players with a greater perceived muscular load (RPEMUSC) experienced a greater decrease in their acceleration capacity (r = 0.48–0.49, p < 0.05). In spite of the fact that neither of the warm-up protocols significantly modified the players’ physical performance, a greater perceived muscular load may cause a greater decrease in acceleration capacity.

Effects of the off-Season Period on Field and Assistant Soccer Referees `Physical Performance

Abstract The evolution of referees’ physical fitness has been studied over one or several seasons, however, the variation of the physical performance between the end of the competitive season (T1) and the start of the following pre-season (T2) has not been ascertained. Therefore, the aim of this study was to analyze the effects of the transition period on physical performance variables (i.e. linear straight sprint, change of direction ability and endurance) in National Soccer Division referees. Forty-five Spanish referees volunteered to participate in this study. Participants were classified according to competitive status, field referees (FR, n = 23) and assistant referees (AR, n = 22). A loss of performance (p < 0.05) was observed in the 20 and 30 m linear straight sprint between T1 and T2 in both FR (1.64-1.56%, d = 0.29 to 0.32) and AR (2.01-3.41%, d = 0.33 to 0.60). In T2 the FR significantly improved the distance covered (p < 0.05, 13.11%, d = 0.39) in the Yo-Yo Intermittent Recovery test (YYIR1). Besides, significant differences were observed between FR and AR in the distance covered (p < 0.05, −23.55%, d = −0.97) in the YYIR1 test in T2. More research may be necessary to focus on the off-season period in order to implement specific training programs and consequently reduce the loss of sprint ability in field and assistant referees and the decrease in cardiovascular fitness in assistant referees.

Relationships between Sprint Ability and Endurance Capacity in Soccer Referees

The aim of this study was to analyze the association between sprint ability and endurance capacity in soccer referees. Twenty-three Spanish officials participated in this study. Each referee undertook, in this order, a 40 m linear straight sprinting test (40 m Sprint) and the Yo–Yo intermittent recovery level 1 test (YYIR1) interspersed with a 8 min of self-administered rest. The results in the 40 m Sprint test showed that the time spent by referees was 5.56 ± 0.27 s and achieved a maximum velocity of 31.46 ± 2.85 km·h−1. Furthermore, during the YYIR1 the referees covered 1213.91 ± 432.26 m. The distance covered at YYIR1 was moderately correlated to the velocity achieved in the 40 m Sprint test (r = −0.404, p < 0.05). These results suggest that the ability to reach high speeds is a limiting factor in YYIR1 performance.

Influence of initial performance level and tactical position on the aerobic fitness in soccer players after preseason period

ABSTRACT Objectives: The purpose of this study was to examine the changes in aerobic fitness in young elite Spanish soccer players after the pre-competitive period over 12 seasons depending on the initial performance level and the tactical position. Methods: One hundred and thirty players belonging to the same reserve team of a Spanish La Liga Club participated in this study. Aerobic fitness capacity (the velocity associated with a blood lactate concentration [La]b of 3 mmol l–1 [V3]) was assessed in each season at the start of the preseason (i.e. July), Test 1 (T1), and the start of the competitive period (i.e. September), Test 2 (T2), from 1998 to 2013 season. Results: Taking all seasons together a most likely small improvement (effect size (ES) = 0.52; ±0.09) was found in V3 after preseason, but this varied from trivial to moderate among the seasons. A most likely large improvement was found for the players with lower V3 values in T1 (ES = 1.68; ±0.38) while a likely small enhancement was assigned to the group with higher V3 values (ES = 0.53; ±0.42). Conclusions: Technical staff should be cautious about affirming an improvement in aerobic fitness after preseason.

The association between physical performance and match-play activities of field and assistants soccer referees

ABSTRACT The aims of this study were to compare the external and internal match responses and fitness performance of national field referees (FRs) and assistant referees (ARs), and to examine the relationships between these fitness measures and physical and physiological responses during match play. Forty-four national soccer match officials (e.g. FRs and ARs) participated in this study. The distance covered and the VO2max in Yo-Yo Intermittent recovery test (YYIR1) and the 30 m sprint test correlated with high speed and high intensity activities during match play in FRs (r = −0.48–0.63, moderate to large, very likely to most likely, p < 0.05). In addition, YYIR1 performance was related to high accelerations (r = 0.41, moderate, likely, p < 0.05) and high decelerations (r = 0.44, moderate, very likely, p < 0.05) for FRs. Better sprint and cardiovascular fitness could be relevant to the performance of FRs during match play.

Differences in Physiological Responses During Wheelchair Basketball Matches According to Playing Time and Competition

ABSTRACT Purpose: The main purpose of the present study was to determine physiological responses in wheelchair basketball (WB) matches in relation to heart rate (HR), match load (ML), differentiated perceived exertion (dRPE), lactate concentrations (LA), and tympanic temperature (TEMP), while specifying the individual player’s playing time during different types of matches. Method: Nine Spanish First Division WB players participated in the study. Three groups were determined for each observation (i.e., HR, ML, dRPE, LA, and TEMP) according to the minutes played by the WB players: players who had played 30 min to 40 min (WB30–40), those who played 20 min to 30 min, and those who played 0 min to 20 min. Results: The WB30–40 group attained statistically significantly higher results in mean HR than the other groups in league and playoff matches (p < .05; Δ% > –25.73%; ES > –1.31, large). With regard to the difference in each variable between league and playoff matches, the differences were highlighted in the WB30–40 group according to ML (Edwards, p < .05, Δ% = –11.14%, ES = –0.87, large; Stagno’s modified TRIMP, p < .05, Δ% = –16.95%, ES = –0.77, large). Tympanic temperature also reached higher values in playoff matches compared with league matches in WB30–40 (p < .05; Δ% = 1.1%; ES = 0.67, moderate) but not in LA values. Conclusions: Coaches should take into account that playoff matches were more demanding than league matches, thus forcing coaches to try to peak WB players’ physical performance for the former.

Differences in Physical Performance According to the Competitive Level in Futsal Players

Abstract The purpose of the present study was to describe performance in acceleration capacity, change of direction ability, vertical jump, horizontal jump, repeated sprint ability, and endurance (Yo-Yo Intermittent Recovery Test Level 1) in futsal players, and analyze the differences according to competitive categories or levels. The total sample (n = 40) was divided into three groups depending on the category in which the participants competed: Second Division B (n = 15), Third Division (n = 12) and juniors (n = 13). All the tests were performed with participants’ regular competition shoes and on the usual playing surface, in an indoor pavilion with a floating wood floor. The results of the study did not show significant differences in acceleration capacity (5 and 15 m) or change of direction ability among the different categories. In contrast, significant differences were found among the categories with regard to horizontal jump and vertical jump capacity (p < 0.05); but not in all the variables analyzed. Performance in repeat sprint ability varied significantly among the different categories in 30 m (p < 0.01) but not in 5 m (p > 0.05). The distance covered in the Yo-Yo Intermittent Recovery Test Level 1 by the Second Division B and the Third Division groups was greater than that covered by the junior group. In the light of these results repeated sprint ability and aerobic endurance could be two discriminating qualities of the competitive level among different futsal categories.

Impact of Official Matches on Soccer Referees’ Power Performance

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.