The Effect of Squad Rotation on Physical Activity at the 2018 World Cup in Russia. Analysis the Most Exploited Players of the 4 Best Teams

Analysing substitutions in recent World Cups and European Championships in male and female elite football - influence of new substitution rules

Substitutions play a key role in modern football and can substantially affect the physical and overall performance of a team, and the recent substitution rule changes are worth investigating. This study explored the characteristics of substitutions, including different substitution rules, game results, sex, competition stages, tournaments and penalty shoot-outs success rates. We analysed data from a total of 3,738 substitutions from the last 10 years (2013-2023) of European Championships and World Cups, both men's and women's games. Non-parametric tests and chi-square tests were used for statistical analysis with the significance level set at p < 0.05. With the 5-substitution rule, 48% more substitutions occurred compared to the 3-substitution rule (4.26 ± 1.07 vs. 2.87 ± 0.43, p < 0.05) with a slight increase in the average substitution time (70.6 ± 14.3 vs. 69.2 ± 14.6 min, p < 0.05), and 10% more substitutions in the men's game compared to the women's game (p < 0.05). The timing of the first substitution was slightly different in the knock-out stage compared to group stage (59.8 ± 14.7 vs. 57.2 ± 13.3 min, p < 0.05), and the timing for the winning team and drawing team was later than for the losing team (p < 0.05). A total of 13.2% goals were scored by substitutes, with no significant difference between the 5-substitution rule (15.9%) vs the 3-substition rule (12.5%) (p > 0.05). Interestingly, substitute players had a lower success rate in penalty shoot-out compared to starters (61 vs. 74%, p < 0.05). Additionally, substitute player goal scorers entered the pitch later (p < 0.05) in male games compared to female games and in knock-out stage games compared to group games. This study highlights the importance of substitution rules and timing in modern elite football matches. The timing of the first substitution, introduction of substitutes in knock-out stages, and a lower success rate of substitute players in penalty shoot-outs are crucial factors to consider. Coaches can use this information to make strategic substitution decisions to improve team performance.

In which rounds were the most rotations of key players made, and how did this affect physical activity? Analysis of the eight best teams of the 2018 FIFA world cup Russia

BACKGROUND

Team management, especially player selection, rotation, and availability, are critical issues when dealing with the high demands of modern training and gameplay. As such, research continuously seeks ways to improve these actions or implement new ideas to gain a competitive advantage through the rotation of players in the starting line-up. The current study aimed to examine the rounds of the 2018 FIFA World Cup Russia in which the most rotations of key players were made and how this affected physical activity.

METHODS

The sample consisted of 110 players from the top eight teams in the 2018 World Cup Russia who played entire matches for up to 90 min in seven consecutive games. All players were divided into key players (KPs, n = 58) and non-key players (NKPs, n = 52). The analysis used data collected by an advanced motion analysis system known as STATS®, with physical activity variables analyzed, including total distance covered (TDC), distance covered with high intensity over 20 km/h (HIR), and the number of sprints undertaken. In statistical analysis, differences between categories and consecutive matches were calculated using the Kruskal-Wallis H test, and if a significant effect size was found, a multiple comparisons p values test was performed.

RESULTS

The best teams at the 2018 FIFA World Cup Russia used the most KP rotations with NKPs in the third match of the group stage. In addition, this was even more visible among more successful teams than less successful teams. The rotation strategy among the best eight teams allowed them to maintain the physical activity of KPs and NKPs in all rounds of the tournament.

CONCLUSIONS

Coaches and coaching staff should incorporate squad rotation that includes a large group of players in their team management to improve their success. Team management expertise in player rotation during matches played over congested schedules at top tournaments maintains high levels of physical activity indicators (TDC, HIR, and sprints).

The seven phases of match status differentiate the running performance of soccer players in UEFA Champions League

The purpose of this research was to investigate the running performance of professional soccer players in relation to seven phases which resulted in the changing or maintaining the match status in the UEFA Champion League games during season 2020/2021. Moreover, we aimed to define which match status phases occur at the earliest stage of regular game time. This study involved professional soccer players from 24 teams participating in the group stage of UEFA Champions League in season 2020/21. The match status was divided into seven phases that result in changing or maintaining the match outcome: DW (Drawing to Winning); LD (Losing to Drawing); WW (Winning to Winning); DD (Drawing to Drawing); LL (Losing to Losing); DL (Drawing to Losing); WD (Winning to Drawing). Such running performance variables as: total distance covered (TDC) and distance covered in high-intensity running (HIR) were analyzed. Players participating in the UEFA Champions League matches cover the longest TDC in DW, DL and DD phases. TDC in these stages was between 111 and 123 m min^-1. The highest HIR was recorded during phases: DW, DL and LL (range between 9.91 and 10.82 m min^-1). In contrast, the lowest total distance and distance in HIR is covered during WD phase (only 105.57 ± 1.89 m min^-1 and 7.34 m min^-1 respectively). On average, phases resulting in the change of the match status occur during the first half, while all phases maintaining the result in the second half. Coaching staffs should consider registering and analysing the physical match performance in relation to described seven match status phases. Such information allows to prepare team-specific training drills, that players should perform more often in order to change or maintain the status of the game.

Do players competing in the UEFA Champions League maintain running performance until the end of the match? Positional analysis between halves and 5-minute intervals

BACKGROUND

This investigation aimed to analyze differences in running performances amongst playing positions between the first and second halves of soccer matches and at 5-minute intervals during matches.

METHODS

Data were collected from 179 soccer players during 20 UEFA Champions League (UCL) 2020/2021 group stage matches. Data were examined using the InStat Fitness semi-automatic video system. Eight variables were selected to quantify players' running performance (RP). Players were categorized based on positional groups: central defenders (CD), fullbacks (FB), central midfielders (CM), wide midfielders (WM), and forwards (FW). Univariate differences in RP were analyzed using ANOVA and the t-test for dependent samples and multivariate differences were identified using canonical discriminant analysis.

RESULTS

The main findings were that all positions achieved significantly higher average speeds and walking distances in the first half of the match than in the second half. Furthermore, analysis of positions showed that CM covered more distance than CD in all 5-minute intervals. In addition, WM performed more high-intensity running than CD in all 5-minute intervals and FW performed more high-intensity running than all other playing positions.

CONCLUSIONS

The findings from the present study should help coaches design training exercises that are specific to parts of a match. Moreover, the findings can help provide better understanding of match demands and individualization of training. Analysis of 5-minute intervals may also help coaches understand the stages of a match where player substitutions will be most effective.

Responses of soccer players performing repeated maximal efforts in simulated conditions of the FIFA World Cup Qatar 2022: A holistic approach

This study aimed to assess the capacity for repeated maximal effort (RME) of soccer players in the thermo-natural conditions (NC) and in simulated conditions for the 2022 FIFA World Cup in Qatar (QSC). Twenty-four semi-professional soccer players participated in the study. The exercise test consisted of ten 6-second maximal efforts on a cycloergometer. A 90-second passive rest interval was used. The test was performed in a Weiss Technik WK-26 climate test chamber in two different conditions: 1) thermo-neutral conditions (NC-20.5°C; 58.7% humidity); and 2) simulated conditions for the 2022 World Cup in Qatar (QSC-28.5 ± 1.92°C; 58.7 ± 8.64% humidity). Power-related, physiological, psychomotor, blood, and electrolyte variables were recorded. Results showed that (1) players achieved higher peak power (max 1607,46 ± 192,70 [W] - 3rd rep), needed less time to peak power (min 0,95 ± 0,27 [s] - 3rd rep), and had a higher fatigue slope (max 218,67 ± 59,64 [W/sek] - 7th rep) in QSC than in NC (in each repetition of study protocol); (2) between the 1st repetition and subsequent repetitions a number of significants in among physiological, blood-related, and electrolyte variables were noted, but their direction was similar in both simulated conditions (e.g. V'O2/kg 37,59 ± 3,96 vs 37,95 ± 3,17 [ml/min/kg] - 3rd rep, LAC 13,16 ± 2,61 vs 14,18 ± 3,13 [mg/dl] - 10th rep or K 4,54 ± 0,29 vs 4,79 ± 0,36 [mmol/l] - 2nd rep when compare QCS and NC respectively); (3) an 8°C of temperature difference between the climatic conditions did not significantly affect the soccer players' physical and physiological responses in RME. The study results can be used in the design of training programs aimed to increase players' physiological adaptations by simulating soccer-specific conditions of play in terms of anaerobic capacity, in particular, repetitive maximal efforts. These findings will be useful during the upcoming 2022 World Cup in Qatar and in locations where high ambient temperatures are customary.

Season Match Loads of a Portuguese Under-23 Soccer Team: Differences between Different Starting Statuses throughout the Season and Specific Periods within the Season Using Global Positioning Systems

This study aimed to quantify the external match loads (EMLs) of a Portuguese u-23 soccer team, competing at the highest national level for the age group, comparing players with different starting status throughout a competitive season and specific blocks. Thirty-five outfield soccer players were split into three groups for the entire season analysis and for each 3-month block, based on the percentage of games played as a starter. The three groups consisted of “starters” (≥55% of the games as a starter), “fringe” (30−54%), and “non-starters” (<30%). EMLs were recorded using 10 Hz GPS technology throughout the whole season (26 matches). Differences (p < 0.05) were found for total distance (TD), exposure time, and the number of accelerations and decelerations between starters and non-starters throughout the season (d = 0.73 to 1.08), and within each block (d = 0.59 to 1.68). Differences were also found between starters and fringe players for the number of accelerations in Block 2 (p = 0.03; d = 0.69), and TD (p = 0.006; d = 1) and exposure time (p = 0.006; d = 0.95) in Block 3. Differences in the EML were almost always accompanied by large differences in game time. Our results highlight the differences in the EML of starters and non-starters, emphasizing the need for compensatory training, especially with players that obtain significantly less playing time, to prepare the players for match demands (e.g., high-intensity efforts such as sprinting, accelerations, and decelerations).