Performance In Soccer Players Research Articles

Effects of Two In-Season Short High-Intensity Interval Training Formats on Aerobic and Neuromuscular Performance in Young Soccer Players

Supplementary high-intensity interval training (HIIT) programs, focusing on different aspects of fitness, are commonly used in soccer practice. This study examined the impact of two different HIIT formats applied during the competitive season on aerobic and neuromuscular performance. Twenty-six young players from two youth amateur soccer teams (aged 18.1 ± 0.7 and 18.7 ± 1.1 years) participated. In a randomized design, Team A served as an experimental group, performing either a 10s/10s linear running HIIT or a 15s/15s HIIT with changes of direction, both at 100% of maximum aerobic speed, twice per week for six weeks. In that period, team B acted as a control group, maintaining their usual training soccer regimen. Following two weeks of lower volume and frequency training, team B added the two HIIT formats in their training for six weeks, while team A acted as control. Before and after each 6-weeks period, aerobic fitness and neuromuscular performance was evaluated by the countermovement jump (CMJ). The 3-way ANOVA showed that both HIIT formats significantly enhanced Yo-Yo Intermittent Recovery Test Level 1 (Yo-YO IR1) performance compared to the respective control periods. However, the main finding was that the 10s/10s compared with the 15s/15s HIIT format induced 45-50% greater improvements in Yo-YO IR1 (total distance: 18.5 ± 11.7% vs. 9.0 ± 8.5%, V̇O2max: 5.6 ± 3.2% vs. 3.0 ± 2.7%, and vV̇O2max: (3.3 ± 1.9% vs. 1.8 ± 1.7%, all p = 0.39, d = 0.85). Countermovement jump performance remained unchanged across both groups (p > 0.68). During HIIT rating of perceived exertion was higher in the 15s/15s vs. the 10s/10s format (6.4 ± 0.5 vs. 4.7 ± 1.2 a.u., p < 0.001). These findings suggest that while both HIIT formats effectively enhance aerobic performance during the season, the 10s/10s format offers superior benefits with less perceived exertion, while the 15s/15s format induces higher internal load.

An Online Training Program Was Effective on Improving Physical Performance and Body Composition in U20 Soccer Players During the COVID-19 Quarantine

Abstract It is recommended for athletes keep training to reduce the negative effects of detraining. This study aimed to verify the effects of a 15-week online training intervention during a pandemic quarantine in body composition and physical capacity of highly trained soccer players. Sixteen male under-20 soccer players were assessed after the first period of COVID-19 quarantine (March 2020 to September 2020; 170 days), and after the second period of COVID-19 quarantine (November 2020 to February 2021, 107 days). Body composition, vertical jump height, hamstring maximum strength and aerobic capacity were assessed. The online training program was performed during the second lockdown. In comparison with first pre assessments, results showed that fat mass (−0.95 ± 1.27), free fat mass (1.22 ± 1.19), squat jump height (5.36 ± 1.99) and counter movement jump (3.19 ± 3.77) were significantly improved (P < 0.05). However, there were no significant changes in total body mass, hamstring eccentric strength, and Yo-Yo IR1 after online training (P > 0.05). In summary, the findings of this study highlight the importance of carrying out a training program during a period of absence from traditional soccer training, in order to maintain the level of physical capacities of youth soccer players.

Effects of Light Versus Very Heavy Resisted Sprint Training on Multidirectional Speed in Semi-professional Soccer Players.

Baena-Raya, A, Robles-Ruiz, J, Pérez-Castilla, A, Pareja-Blanco, F, and Rodríguez-Pérez, MA. Effects of light versus very heavy resisted sprint training on multidirectional speed in semi-professional soccer players. J Strength Cond Res XX(X): 000-000, 2024-The purpose of this study was to evaluate the effects of an 8-week resisted linear sprint training (RST) program with 2 loading conditions (light vs. very heavy) on linear sprint (LS), curve sprint (CS), and change of direction (COD) performance in young soccer players. Thirty-eight male under-19 soccer players were assessed for 30-m LS, CS, and modified 505 COD tests. Players were randomly allocated into 3 groups: control (n = 18), light (n = 10), and very heavy RST (n = 10). Light and very heavy RST groups performed RST with external loads resulting in a 25 and 75% velocity loss from the player's maximal LS velocity, respectively. The control group did not perform any sprint training. Significant group × time interactions were observed for LS, CS, and COD performances (p < 0.05). The control group showed no performance improvement. Both RST groups showed significant improvements in LS at 10-, 20-, and 30-m (p ≤ 0.03; effect size [ES] ≥ 0.62), whereas no significant changes were observed for the split times (p > 0.05). CS performance was significantly increased by the 2 RST groups (p ≤ 0.03; ES ≥ 0.60), except for light RST on CS right side at 17-m (p = 0.09; ES = 0.46). Change of direction performance was only significantly enhanced by the very heavy RST group (p ≤ 0.001; ES ≥ 0.80). No significant changes between RST groups were observed. In conclusion, using both light and very heavy RST can enhance LS and CS performance, whereas very heavy RST is recommended to optimize COD performance in young soccer players.

The Impact of Anterior Cruciate Ligament Tear on Player Performance and Longevity in La Liga League Soccer Players

AbstractAnterior cruciate ligament (ACL) rupture is among the most studied sports injuries. We investigate the impact of ACL reconstruction (ACLR) on performance and longevity in La Liga to elucidate performance parameters impacted after surgery in professional soccer players and variables impacting return-to-play (RTP).Demographic and performance data for La Liga players with ACLR between 1993 and 2020 were collected three seasons before and after injury and compared with two healthy controls. Analysis was conducted between and within ACLR and control groups. Pearson's correlation coefficients and a multiple linear regression model analyzed relationships between demographic variables and RTP.After exclusion, 23 professional soccer players were identified for the ACLR group. One year after index, ACLR had lower goals, shots on-target, assists, pass percentage, tackles, tackle success percentage, blocks, and clearances compared with control (p &lt; 0.05). Two years after index, ACLR had lower assists, pass percentage, and tackle success percentage than control (p &lt; 0.05). Three years after index, ACLR had fewer matches and blocks versus control (p &lt; 0.05). Pearson's correlation showed a positive correlation between experience and RTP (p = 0.001). Multiple linear regression found RTP to increase 32.66 days for each additional year of experience (p &lt; 0.001).With performance metrics showing significant decreases up to 2 years post-ACLR but largely recovering within 3 years of RTP, results support that soccer players undergoing ACLR eventually recover to preinjury levels of play. Players should be counseled on initial declines in performance metrics the first few years after RTP.

The Relationship Between Playing Formations, Team Ranking, and Physical Performance in the Serie A Soccer League

The influence of playing formations and team ranking on the physical performance of professional soccer players is an open question that needs to be explored. The present study aimed to investigate the impact of these factors on the physical exertion of Serie A soccer players. We analyzed match data from 375 players, categorizing teams based on their final ranking and comparing performance across different playing formations. The Kruskal–Wallis test and the Dunn test with Bonferroni adjustment revealed that high-ranking (HR) teams exhibited a higher percentage of high-intensity (HI) accelerations compared to mid-ranking teams, suggesting the critical role of HI efforts in achieving favorable match outcomes. Moreover, the 4-3-3 playing formation was associated with greater acceleration demands than other formations, particularly in HR teams. Our study also established benchmarks for various performance metrics, enabling coaches to assess player performance and identify potential signs of overtraining. These findings contribute to a deeper understanding of the physical demands in soccer and offer practical implications for coaches and players in optimizing training and performance strategies.

Age Is a New Indicator of Long-Ball Kicking Performance in Young Soccer Players: Analysing Kinanthropometry, Flexibility and Strength

(1) Background: The kick of the ball in soccer is considered one of the most important technical gestures in soccer. Despite this, there is little evidence on ball-striking performance factors in base soccer. The main objectives of the present study were to identify the potential factors of long-ball kicking (LBK) performance and to determine the target training cut-off for LBK performance in young soccer players. (2) Methods: A cross-sectional observational study was conducted with 31 soccer players, with ages ranging from 12 to 18 years. Age, anthropometric data, sport experience, range of motion (ROM) and maximal isometric strength (MIS) of the lower limb were noted. Kick-of-the-ball performance was assessed by maximum ball displacement per kick. A k-mean cluster analysis determined two groups according to ball-kicking performance: low group (LPG-LBK) and high group (HPG-LBK). (3) Results: Differences were found between both groups in age, body mass, body mass index, leg length and knee flexion ROM (BF10 ≤ 6.33; δ ≥ 0.86 (moderate or higher)). Among the factors discussed above, age was the strongest predictor of ball-striking performance (odds ratio = 2.867; p = 0.003). The optimal cut-off for age predicting those players most likely to have a higher ball-striking performance was determined to be 13.5 years (p = 0.001; area under the curve = 85.3%). (4) Conclusions: Age over 13.5 increases the chances of a higher optimal ball-striking performance. The flexibility (knee flexion ROM) and strength (knee flexors) must be specifically trained in soccer players beginning at an early age.

Less Total-Body Fat and Lower-Extremity Fat Are Associated with More High-Intensity Running during Games in Female University Soccer Players

This study examined the relationship between body composition and on-field, in-game physical performance in female collegiate soccer players. Body composition, including total mass, fat mass, and lean tissue mass for the lower extremities and total body, was measured in 10 starting players using dual energy x-ray absorptiometry (DXA). On-field, in-game physical performance was tracked via a global positioning system (GPS) over 14 regular-season games, measuring total distance and distance covered in six speed zones. Players covered 4544.7 ± 495.2 m in the first half of the game and significantly less distance in the second half (3356.5 ± 1211.7 m, p = 0.004). A repeated measures ANOVA revealed decreased distances in jogging, low-, and moderate-intensity running during the second half compared to the first half of the game (p &lt; 0.001). Lower total-body fat mass, total-body fat percentage, and lower-extremities fat mass were correlated with greater distances at moderate- and high-intensity running during the second half and entire game (r values from −0.644 to −0.745, p &lt; 0.01 to 0.04). These findings suggest that body composition can influence the distance covered at moderate- and high-intensity running speed during competitive games. Training strategies aimed at reducing fat mass and incorporating high-intensity training may benefit female soccer players and enhance team success.

Physical fitness, psychological characteristics, and game performance in youth male soccer players of different levels of competition

ABSTRACT This cross-sectional study examined the differences and associations regarding physical fitness, psychological characteristics, and game performance between elite (n = 64), sub-elite (n = 82), and non-elite (n = 97) youth male soccer players aged 16.2 ± 0.5 years. Physical fitness parameters were assessed using field tests, psychological characteristics were evaluated using validated questionnaires and technical – tactical data were recorded during a competitive soccer match using a multicamera, semiautomatic optical tracking system. Elite players demonstrated superior performance in cardiorespiratory fitness, countermovement jump (CMJ), 10 m sprint, and agility, compared to the sub-elite and the non-elite players. Also, the elite and sub-elite players had faster 40 m sprints than the non-elite players. Game performance was significantly better in the elite group than the other groups and was associated with coping with the adversity and coachability, tension-anxiety, anger-hostility, and fatigue-inertia subscales. Among the physical fitness parameters examined, only agility and CMJ were associated with game performance. In conclusion, elite youth soccer players performed significantly better in various physical fitness and psychological parameters and demonstrated a higher game performance indicator score compared to their sub-elite and non-elite peers. Results suggested that physical fitness and psychological parameters are essential predictors of game performance.

Effects of resisted sprint training with ball on speed and agility performance in U-19 elite soccer players.

The purpose of this study was to analyze the effects on speed and agility of including ball driving during resisted sprint training in relation to regular soccer training. Thirty male soccer players (age: 18.10 ± 0.66 years; height: 179 ± 0.06 cm; body mass: 76.22 ± 4.76 kg; systematic practice: 8.6 ± 1.73 years) participated in the study and were randomly assigned to an experimental group (EG; n = 18) or a control group (CG; n = 12). The research was conducted during a training camp. The intervention period lasted 6 weeks and during that period all players performed their usual soccer training. However, the EG performed two weekly sessions of a supplementary training of resisted sprints with a ball. Within-group analysis showed significant improvements in 5-m (p = 0.005) and 10-m (p = 0.016) sprint performance; and New multi-change of direction agility test (NMAT; p = 0.002), Illinois (IAT; p = 0.002), T-test (p = 0.003), Arrowhead COD (Arrowhead-R, p = < 0.001; Arrowhead-L, p = < 0.001) test and Zigzag agility test (Zigzag-B; p = 0.006) from pretest to posttest in EG. However, the CG didn't show any significant improvements. Between-groups analysis revealed differences in favor of the EG in Zigzag-B, IAT, Arrowhead-R, Arrowhead-L and NMAT. This study's results support the efficacy of a short-term training program that includes resisted sprints exercises to improve the performance of soccer players.

Association Between Field Test Performance And Match Physical Performance In Collegiate Female Soccer Players

Association Between Field Test Performance And Match Physical Performance In Collegiate Female Soccer Players

No transfer of 3D-Multiple Object Tracking training on game performance in soccer: a follow-up study

The impact of domain-general cognitive ‘brain’ training on improving sports performance is highly debated. This study sought to follow-up on research that showcased the benefits of perceptual-cognitive 3D-Multiple Object Tracking (3D-MOT) training in enhancing the on-field performance of soccer players. Additionally, it explored the correlation between athletes’ cognitive performance and early career success.Sixty-two males from a professional soccer academy were randomly divided into a dual-task 3D-MOT training group (n=30) and a control group (n=32). Participants underwent a 3D-MOT test, a cognitive test of attention, and small-sided games at pre- and post-training. Pre-post-test performances were compared using ANCOVAs. A Chi-squared test evaluated the association between the training regimen and early career success. A Spearman test assessed the correlation between performance on the 3D-MOT, attention test, and early career success.The dual-task 3D-MOT trained group significantly improved its performance on 3D-MOT compared to the control group (p < 0.001). However, no significant pre-post-test differences were observed between the groups in the near-transfer cognitive test and on-field performance (ps > 0.05). There were no associations between the athletes’ early career success and the training regimen, and no associations between cognitive test performances and early career success (ps > 0.05).This follow-up study failed to replicate previous findings with dual-task 3D-MOT training unable to produce near or far transfer on soccer performance. In addition, cognitive performance was not related to early career success in this study. The value of cognitive screening and training in sport is discussed.

Analysis of match performance of elite soccer players across confederations during the Men’s and Women’s World Cup

ABSTRACT This study aimed to benchmark and analyze match performance of elite soccer players from various confederations during the FIFA World Cup Qatar 2022 (Men’s WC) and FIFA Women’s World Cup Australia and New Zealand 2023 (Women’s WC). A total of 128 matches were analyzed using an optical tracking system (n = 1,351 player observations). Players from various national teams were categorized into their respective confederations: Europe (UEFA), South America (CONMEBOL), North/Central America and Caribbean (CONCACAF), Africa (CAF) and Asia and Oceania (AFC/OFC). Generalized Linear Mixed Models and Linear Mixed Models were employed to assess performance differences between confederations. Data revealed that CONMEBOL players in the Men’s WC covered less total distance than UEFA players (p = 0.0396; ES = 0.6). However, no differences were found in high-intensity running and sprinting distances across confederations in both tournaments. UEFA players in both competitions typically demonstrated superior technical/tactical performances. In particular, UEFA players in the Women’s World Cup made more passes, had 7–16% higher pass completion rates and achieved 10–15% greater line break completion rates compared to those from CAF, CONCACAF and AFC/OFC (p < 0.0001 to p = 0.0199, ES = 0.5–1.3). These findings suggest that UEFA players may possess a tactical/technical edge in international competitions. However, caution should be exercised when interpreting data due to high variations within confederations. This is the first comprehensive study describing match performance between confederations during the Men’s and Women’s WC, providing valuable insights into the physical and technical/tactical aspects of elite soccer.

Knee muscle strength, body composition, and balance performance of youth soccer players

BackgroundMuscle strength and balance abilities have been related to game performance injury prevention. This study aimed to (1) assess knee muscle strength performance based on intra- and inter-limb asymmetries, (2) investigate the relationships between knee muscle strength, body composition, and balance, and (3) analyze the variance in the overall stability index (OSI) explained by knee muscle strength indicators after controlling for age and body composition.MethodsThe sample included 104 young male soccer players (16.0 ± 1.6 years). Body composition, knee muscle strength, and balance ability were assessed. A paired samples t-test was used to examine differences between the preferred leg (PL) and the non-preferred leg (NPL). Pearson correlations and hierarchical multiple regression were conducted to explore the relationships between strength, body composition, and balance.ResultsNo significant inter-limb asymmetries were detected for the knee flexors (KF) and knee extensors (KE) performance. The hamstrings-to-quadriceps ratio does not suggest the existence of intra-limb asymmetries (p = 0.06). Significant and negative correlations were found between KF (r = -0.38, p ≤ 0.01) and KE (r = -0.58, p ≤ 0.01) for the PL. Concerning the NPL, KE also revealed a significant and negative relationship with balance (r = -0.30, p ≤ 0.01). Significant and positive relationships were found between bodyweight, fat-free mass, and balance. After controlling for age and body composition, knee muscle strength could explain between 13% and 30% of the variance observed in the OSI (NPL and PL, respectively).ConclusionsThe results underline knee muscle strength as an important predictor of balance. Thus, training programs targeting knee muscle strength development should be considered during the season periodization by coaches and their staff throughout the players’ developmental stages.

Reliability of single-leg maximal dynamic strength performance and inter-limb asymmetries in pre-pubertal soccer players. The influence of maturity in asymmetries

The aims of this repeated measures study were (I) to determine the reliability of single-leg squat 1RM and inter-limb asymmetries in pre-pubertal athletes, and (II) to assess associations between bilateral and/or unilateral squat 1RM performance, inter-limb asymmetries, and participants’ chronological and biological age. Thirty-one soccer players (age [mean ± standard deviation] = 8.48 ± 0.47 years; body mass = 28.32 ± 3.47 kg; body height = 121.70 ± 4.11 cm) practiced two familiarization and two experimental sessions. Bilateral and unilateral squat 1RM and asymmetries between both legs were assessed. Biological age was obtained through the age at peak height velocity (12.87 ± 0.38 years) and maturity offset (3.92 ± 0.44 years). Absolute and relative reliability and Pearson's correlations were calculated. Right and left leg 1RM and asymmetries presented good relative reliability (ICCrange = 0.84–0.85) levels, but non-acceptable absolute reliability (CV ~ 12 %). Asymmetries presented trivial to small correlations with strength (Range = 0.01–0.11). Similarly, chronological, and biological age presented small correlations with strength and asymmetries (Range = 0.01–0.22). Considering the good reliability, the bilateral and unilateral 1RM back half squat test can be considered in youth soccer players. Finally, lower-body mechanical performance and asymmetry between legs show trivial to small correlations, with maturation not affecting asymmetry in male youth soccer players. In conclusion, strength and power activities and training should be placed on younger soccer players with high asymmetry scores regardless of their stage of maturation.

The Evaluation of the Modified Wave Periodization Model Efficiency on the Example of Young Soccer Players' Sprint Tests

The research aimed to evaluate the modified model of wave periodization efficiency in running speed tests conducted among soccer players aged 12 to 16. Participants included prospective players of a leading Polish top league soccer club. The research was carried out from 2018 to 2022 in June (Testing A) and December (Testing B) of each year. The test involved 30-m straight line running with 5-, 10-, and 30-m split time measurements. For this purpose, electronic photocells were used (FITLIGHT, Canada). The six-month training intervention increased the athletes' speed as there was a considerable decrease in the running time over the distance of 5 m (F = 7.86; p &lt; 0.001), 10 m (F = 73.99; p &lt; 0.001) and 30 m (F = 127.55; p &lt; 0.001). Analysis of running performance of young soccer players aged 12–16 showed a significant improvement in speed at distances of 5, 10 and 30 m, confirming training effectiveness based on the wave periodization model. The negative correlation between testing year and performance suggests the influence of biological development on players' speed. The COVID-19 pandemic has impacted training, which was reflected in reduced differences between test scores. Improving initial running technique can contribute to better match results, which emphasizes the need for an individual approach to the physical preparation of players.

Analysis of the impact of different intensities and time periods on the physical and technical performance of professional soccer players

Soccer match simulations provide valuable information on player performance and training methods but how intensity during a game affects a player's physical/technical performance has yet to be explored. The objective of the study was to analyse the impact of variable intensity intervals during the first block of the Copenhagen Soccer Test. A repeated measures study was designed to compare three intensity levels, three time periods and their effects on sprint speed, perceived effort, goal shooting accuracy, dribbling, and long pass accuracy in professional soccer players. The comparison analysis between different phases showed a significant decrease in sprint speed (p &lt; 0.001) and an increase in perceived effort (p &lt; 0.001), however, the technical variables did not change (p &gt; 0.05). When comparing the data based on intensity, significant decreases were observed in all variables (p &lt; 0.001). The combined analysis of the results indicates that the speed decreases and the rate of perceived exertion increases as the simulation progresses. Meanwhile, the accuracy of goal kicks, dribbling, and long passes are negatively affected by high-intensity efforts, but demonstrate recovery over the course of the simulation. The increase in intensity affects the speed more than the accuracy of shots on goal, dribbling and passing. Keywords: Performance, Soccer, Intensity, Physical performance, Technical performance.

Ecological-Dynamic Approach vs. Traditional Prescriptive Approach in Improving Technical Skills of Young Soccer Players.

Background: This study contributes to expanding the existing literature on learning technical skills in youth soccer by comparing the effectiveness of different training approaches in the development of passing skills. The ecological-dynamic approach, which emphasizes the continuous and adaptive interaction between the athlete and the environment, is analyzed in comparison to the traditional prescriptive approach, which relies on predefined techniques and exercises. The aim of the study is to determine which of the two approaches is more effective in improving the performance of young soccer players. Methods: Thirty players (age 12 ± 1.2 years) were randomly assigned to two groups: the ecological-dynamic group (ECG) and a control group (CON). Both groups underwent an eight-week training program with equal sessions. The ECG group's training focused on adjusting constraints like the learning environment, game rules, and visual restrictions to boost adaptability and problem-solving skills. The CON group followed a traditional prescriptive approach with specific instructions, goal setting, immediate feedback, and structured exercise progression. Passing abilities were evaluated before and after the program using the Loughborough Soccer Passing Test, with a retention test administered five weeks later. Descriptive statistics, including mean values and percentage improvements, were used. A repeated measures ANOVA compared differences between the groups. Results: The analysis revealed a significant Occasion × Group interaction for all performance variables, indicating that the ECG group experienced greater improvements than the CON group. Specifically, the ECG group showed significant reductions in Trial Time (p = 0.001, ηp2 = 0.6), Penalty Time (p = 0.016, ηp2 = 0.4), and Overall Performance (p = 0.011, ηp2 = 0.8) from pre-test to post-test. However, these improvements did not persist into the retention test (p = 0.131, p = 0.792, and p = 0.192, respectively). The CON group also improved significantly in Trial Time (p = 0.003), Penalty Time (p = 0.002), and Overall Performance (p = 0.001) from pre-test to post-test, but with smaller effect sizes and no sustained gains at retention. Conclusions: The ecological-dynamic approach (EDG) has proven to be more effective in enhancing passing skills compared to the traditional prescriptive approach (CON). Although both methods led to performance improvements, the EDG group achieved more significant progress.

COVID-19 affects match running performance in professional soccer players

Objectives: To compare the match running performance of male soccer players in the Brazilian A series before and after being infected with COVID-19. Methods: The sample consisted of 20 professional soccer players from Rio de Janeiro-based teams during the 2020 and 2021 seasons, pre- and post-COVID-19 infection. Match running performance data were collected using a Global positioning system (GPS), and the analysis includes average data across 1 to 17 games pre-infection and 1 to 13 games post-infection per player. Results: COVID-19-infection induced an unclear effect on the total distance traveled during the match [SWC-Factor = -1.9, 90 % CL (-4.7; 0.9)], the number of sprints at speeds over 24 km/h [SWC-Factor = 1.1, 90 % CL (-1.7; 3.9)], maximum speed reached [SWC-Factor = 0.1, 90 % CL (-2.6; 2.9)], the number of decelerations [SWC-Factor = -2.2, 90 % CL (-5.0; 0.6) ], explosive efforts [SWC-Factor = -2.4, 90 % CL (-5.1; 0.4) ], distance traveled at speeds between 0 and 7 km/h [SWC-Factor = 2.4, 90 % CL (-0.4; 5.2) ], and distance traveled at speeds between 7 and 14 km/h [SWC-Factor = -1.8, 90 % CL (-4.5; 1.0) ]. However there was a moderate and significant decrease in distance covered during high-intensity running, defined as speeds greater than 20 km/h [SWC-Factor = -4.2, 90 % CL (-7.0; -1.5) ], the number of accelerations greater than 3 m/s² [SWC-Factor = -3.6, 90 % CL (-6.4; -0.9) ], and distance traveled at speeds between 14 and 20 km/h [SWC-Factor = -3.5, 90 % CL (-6.2; -0.7) ]. The results also showed that COVID-19-infection led to a substantial decrease in minutes played during matches [SWC-Factor = -4.0, 90 % CL (-6.8; -1.3)], affecting the analysis of match variables' absolute values. Conclusion: The results suggest that players infected with COVID-19 experienced changes in match running performance, notably decreases in distance covered during high-intensity running and increases traveled at speeds between 0 and 7 km/h. Further analysis of other player populations (in other leagues) is necessary to verify these findings. Keywords: Coronavirus, Physiology, Task Performance and Analysis, Match running, External Load.

Effects of Music on Repeated-Sprint Performance of Elite Tunisian Soccer Players: Comparing Morning to Afternoon Practice Sessions.

Our aim in the present study was to examine the effect of listening to self-selected music during soccer warm-ups in morning and afternoon sessions on repeated-sprint performances of elite soccer players. Twenty elite academy male soccer players performed a repeated-sprint ability (RSA) test in the morning (i.e., 07:00hours) and in the afternoon (i.e., 17:00hours), with or without listening to music during the warm-up period. The RSA test consisted of six 40-meter sprints with 180° direction changes interspersed with a 20-second passive recovery period. Ratings of perceived exertion (RPE) were obtained at the end of the warm-up period and immediately after the RSA test. Results showed that listening to music during warming-up had no significant effect on these selected performance measures (i.e., mean sprint time, best sprint time, RSA decrement), regardless of whether performances were in the morning or the afternoon. Moreover, players reported higher post-warm-up RPE scores in the music listening condition than in the no-music listening condition, only in the afternoon session. Furthermore, RPE scores measured after the RSA test were higher in the no-music listening condition compared to the music listening condition, only in the morning session. Thus, the use of music during warming-up in elite soccer players appears to be an individual athlete's choice but not a reliable means of enhancing performance.

Effect of Speed, Agility, and Quickness Training on Linear Sprint, Jump, and Change of Direction Speed Performance in Soccer Players: A Systematic Review and Three-Level Meta-Analysis

Effect of Speed, Agility, and Quickness Training on Linear Sprint, Jump, and Change of Direction Speed Performance in Soccer Players: A Systematic Review and Three-Level Meta-Analysis