Elite Soccer Research Articles

Ultrasound-guided interventions in elite soccer players.

In the world of elite soccer, or football as we call it in the UK, a player who cannot play for any length of time costs the team money and team performance. The time to return to play (RTP) is crucial in any player's career, and the use of ultrasound-guided ultrasound injections has become important in the management of injury. In this article, I will explain the importance of good practice when performing these procedures and the use of steroids, sodium hyaluronic acid, platelet-rich plasma (PRP), and other therapies in achieving the goal of decreasing the time of RTP for the footballer. KEY POINTS: •Injection therapies are routine practice in maintaining and treating soccer injuries. •Injection therapies can be safely performed under ultrasound guidance.

Recovery patterns of low-frequency fatigue in elite youth soccer players after official match

This study aimed to analyze the associations between recovery of low-frequency fatigue, jump height and perceptual responses following official soccer matches. Forty-two male youth elite soccer players (age: 17.13±0.70 years; height: 179.17±5.94 cm; weight: 69.74±4.91 kg) participated in this study. Low-frequency fatigue, countermovement jump, perceived fatigue, muscle soreness and perceived recovery were assessed at -2h, +30 min, +24h and +48h relative to the match. Linear mixed models analysis showed that low-frequency fatigue was reduced at the match-end (ES=-0.679 [95% CI = -1.01; -0.34]; p<.001) but returned to baseline after 24h (ES=0.149 [95% CI = -0.26; 0.56]; p=1.00). Perceptual responses were impaired for up to 48 hours following the match (ES=-0.868–1.174; p<.001). Countermovement jump did not differ between any time point (ES=-0.204–0.216; p>0.05). Additionally, the within-subject correlation analysis showed that low-frequency fatigue pre- to post-match changes presented moderate to large associations with perceived fatigue (rm[57]=-0.43; p<.001), muscle soreness (rm[57]=-0.52; p<.001) and perceived recovery (rm[57]=0.38; p=.003). The assessment of low-frequency fatigue could serve as an additional objective measurement for monitoring post-match fatigue, as findings suggest that young elite soccer players experience transient reductions following match-play, which are strongly correlated with subjective markers of recovery.

Contextualised physical metrics: The physical demands vary with phase of play during elite soccer match play.

The physical demands of elite soccer match play have traditionally been measured using aggregated whole-match metrics. However, match play is increasingly considered as distinct phases of play, although the influence of phase of play on match physical demands remains largely unknown. This study compared physical intensity, acceleration and deceleration demands, between phases of play and according to playing position. The duration of each match from a major European league (n=1083) was divided into one of five reciprocal phases (for the in-/out-of-possession team) using event and tracking data: build-up/high-block, progression/mid-block, chance creation/low-block, fast attack/fast defence, or attacking transition/defensive transition. Player tracking data were used to calculate physical intensity as the rate of distance covered (m⋅min-1) in total and within five speed categories, and the proportion of time spent accelerating and decelerating (>2ms-2) during each phase of play. Rate of distance covered in total differed markedly with phase of play; fast attack 35%-53% greater, and fast defence 33%-50% greater, than other in-/out-of-possession phases respectively, and these effects were amplified for the rate of distance covered at higher speeds (e.g., sprinting ≥4-fold differences between phases). Match phase also affected the proportion of time spent accelerating and decelerating (highest for fast attack and chance creation, respectively), especially when in-possession for forwards and when out-of-possession for defenders (p<0.001). Phase of play had a large effect on the physical intensity of match play, particularly rates of distance covered at higher speeds, as well as the acceleration and deceleration demands, and in a position specific manner.

Environmental Heat Stress Detrimentally Affects Match Running Performance of Elite Soccer Teams Competing in the UEFA Champions League.

Modric, T, Clemente, FM, Versic, S, Chmura, P, Andrzejewski, M, Kryściak, J, and Sekulic, D. Environmental heat stress detrimentally affects match running performance of elite soccer teams competing in the UEFA Champions League. J Strength Cond Res XX(X): 000-000, 2024-This study aimed to examine the effect of environmental heat stress (EHS), defined by wet-bulb globe temperature (WBGT), on match running performance (MRP) while controlling for match-related contextual factors. For this purpose, 2 approaches were implemented: (a) the MRP in heat stress nonrisking environment (NoEHS) (WBGT <22° C) and heat stress risking environment (EHSrisk) (WBGT ≥22° C) were compared and (b) changes in MRP according to the 1° C increase in WBGT were evaluated. Data on MRP were collected using an optical tracking system from all teams ( n = 32) in all UEFA Champions League matches ( n = 125) during the 2022-23 season. Metrics included total distance (TD), low-intensity (LIR), moderate-intensity (MIR), and high-intensity running (HIR) distances. Results indicated that less TD (108.84 vs. 110.71 km; Cohen's d [ d ] = 0.53), MIR (15.91 vs. 17.09 km; d = 0.85), and HIR (8.75 vs. 9.23 km; d = 0.46) were covered in matches played in EHSrisk compared with the NoEHS. Further investigation indicated that for every 1° C increase in WBGT, TD averagely decreased by 0.16 km ( d = -0.48), MIR by 0.13 km ( d = -1.09), and HIR by 0.06 km ( d = -0.69). These findings demonstrated decreased overall and intensive workload during the matches in EHSrisk, suggesting the detrimental effect of EHS on match volume and intensity in elite soccer. When EHS risk is anticipated, consideration of playing and recovery strategies should be implemented by coaches to achieve tactical goals while minimizing physical strain during a match.

Pricing in response to new information: The case of betting markets

AbstractMarkets are information aggregators. But how do they incorporate new data into their pricing? We examine the response of prediction markets to a novel information shock in a quasi‐natural experiment: How did the absence announcements of elite soccer players influence the betting odds of affected matches? Analyzing the first four statistical moments of 117,174 odds from 32 bookmakers, we identify initial inertia followed by a lagged reaction that we cannot reason with learning. Our findings raise questions about how bettors and bookmakers incorporate new information into their beliefs. It has broader implications regarding information processing in markets.

Self-regulation and performance among elite youth soccer players: the role of approach-avoidance motivation.

This study aimed to investigate the motivational processes behind self-regulated learning and performance among 192 soccer players (82 girls) for three age groups (14-16 years old) eligible for the Norwegian national football team. A conditional process model was proposed and tested with achievement goals as mediators between achievement motives on the one hand and coach-reported performance and self-regulated learning on the other hand. The probability of success was examined as a potential moderator in the motivational process. As predicted, motives to achieve success directly influenced planning and reflection/evaluation, whereas the influence of the success motive on regulation of effort was explained partly by task- and self-based approach goals. The motive to achieve success was, however, particularly crucial for maintaining these beneficial regulatory processes when the probability of success was found to be from moderate to low. Concerning the avoidance paths, the data supported only some of our original hypotheses. The motive to avoid failure predicted all three types of avoidance-based (task, self, and other) and other-based approach goals but did not contribute to explaining planning, reflection/evaluation, regulation of effort, or performance. There were no significant correlations between motivation variables and coach-reported performance. Moreover, girls were more motivated to avoid failure than boys, while both sexes achieved similar scores for football-specific self-regulated learning, probability of success, achievement goals, and motive to achieve success. The results are discussed considering a hierarchical motivation model.

Validity and Reliability of a New Wearable Chest Strap to Estimate Respiratory Frequency in Elite Soccer Athletes.

Assessing respiratory frequency (fR) is practical in monitoring training progress in competitive athletes, especially during exercise. This study aimed to validate a new wearable chest strap (wCS) to estimate fR against ergospirometry as a criterion device in soccer players. A total of 26 elite professional soccer players (mean [standard deviation]: 23.6 [4.8] years; 180.6 [5.7] cm; 77.2 [5.4] kg) from three Italian Serie A League teams participated in this cross-sectional study. The sample included attackers, midfielders, and defenders. fR was assessed during a maximal cardiopulmonary exercise test (CPET) on a treadmill using (i) a breath-by-breath gas exchange analyzer (Vyntus® CPX, Vyaire Medical) and (ii) a novel wCS with sensors designed to assess breath frequency following chest expansions. Pearson's correlation coefficient (r), adjusted coefficient of determination (aR2), Bland-Altman plot analysis, and Lin's concordance correlation coefficient (ρc) were used for comparative analysis (correlation and concordance) among the methods. The repeated measures correlation coefficient (rrm) was used to assess the strength of the linear association between the methods. The intraclass correlation coefficient (ICC) and the Finn coefficient (rF) were used for inter-rater reliability. All statistical analyses were performed within the R statistical computing environment, with 95% confidence intervals (95% CIs) reported and statistical significance set at p < 0.05. A total of 16529 comparisons were performed after collecting the CPET data. The robust time series analysis with Hodges-Lehmann estimation showed no significant differences between both methods (p > 0.05). Correlation among devices was statistically significant and very large (r [95% CI]: 0.970 [0.970, 0.971], p < 0.01; aR2 [95% CI]: 0.942 [0.942, 0.943], p < 0.01) with strong evidence supporting consistency of the new wCS (BF10 > 100). In addition, a high concordance was found (ρc [95% CI]: 0.970 [0.969, 0.971], bias correction factor: 0.999). VyntusTM CPX, as a standard criterion, showed moderate agreement with wCS after Bland-Altman analysis (bias [95% lower to the upper limit of agreement]; % agree: 0.170 [-4.582 to 4.923] breaths·min-1; 69.9%). A strong association between measurements (rrm [95% CI]: 0.960 [0.959, 0.961]), a high absolute agreement between methods (ICC [95% CI]: 0.970 [0.970, 0.971]), and high inter-rater reliability (rF: 0.947) were found. With an RMSE = 2.42 breaths·min-1, the new wCS seems to be an valid and reliable in-field method to evaluate fR compared to a breath-by-breath gas exchange analyzer. Notwithstanding, caution is advised if methods are used interchangeably while further external validation occurs.

Elite women's soccer match demand can be described using complexity-based analyses and multifractals

The present study aimed to investigate the variability of the displacements in elite women soccer players during official matches according to the position of the players and to the match progression using non-linear analyses (entropy and multifractal spectrum).Sixty-three velocity profiles from global positioning devices of elite professional women soccer players were analyzed. The mean, coefficient of variation, and maximum velocity were calculated during the match using four equal segments. Sample entropy and seven parameters derived from the multifractal detrended fluctuation analysis were also calculated. The players were split into five field playing positions: forwards (FW), offensive midfielders (OM), defensive midfielders (DM), central defenders (CD), and lateral defenders (LD).No significant playing position × period interaction was found for the different parameters analyzed. However, most parameters showed a significant main effect for playing position (p < .01) and period (p < .01). Compared to the other players, FW and OM have the lowest entropy. All players showed a dominance of small velocity fluctuations but FW players showed the widest multifractal spectrum primarily. In contrast, CD had a narrow spectrum and reduced amount of small fluctuations. As the game progressed, mean velocity and entropy significantly decreased. In contrast, the multifractal peak value significantly alongside with changes in asymmetry.From the present results, velocity profiles during elite women's soccer games depicted multifractal features sensitive to player position and match segment, which can help to understand the dynamics and variability of players' responses during a match.

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.

Improvements in executive functions by domain-specific cognitive training in youth elite soccer players

This study examined the impact of sport-specific cognitive training (CT) on executive functions (EFs) in youth soccer players. Thirty-one athletes (13–15 years) participated, 13 in the intervention group (IG) and 18 in the control group (CG). The IG underwent an 8-week soccer-focused CT program, while the CG maintained regular training. The assessments included working memory, inhibition, and cognitive flexibility tasks. The results revealed no significant improvements in EFs in the IG compared to those in the CG. Both groups showed enhanced cognitive flexibility, possibly due to general cognitive development or learning effects. The study suggested that an 8-week sport-specific CT may not enhance EFs in young soccer players, potentially due to a ceiling effect in highly skilled athletes. These findings should be considered when designing cognitive training programs for athletes, and future research could explore the optimal duration of such programs.

Strength And Functional Asymmetries In Elite Soccer Players

Strength And Functional Asymmetries In Elite Soccer Players

Is Travel Associated With Match Performance in Elite North American Professional Soccer? An Exploratory Study.

Travel fatigue impacts cognitive and physiologic systems, but its association with elite soccer match performance is unclear. In this retrospective observational study, we aimed to explore the association between travel and match outcomes in elite North American soccer. Travel data and match outcomes(team points or goals scored and conceded) and physical performance outcomes from 26 elite professional soccer teams and their players were analyzed (148 matches [team-based data] and 1252 player matches from 297 players; age 22.7 [4.5]y). Player- and match-level correlations between performance measures and both acute and cumulated travel metrics were analyzed. Cumulative travel metrics were positively associated with team (travel distance [r = .20; 95% CI, .03-.25], travel time [r = .20; .06-.37], and time away [r = .20; .06-.37]) and individual player (travel distance, [r = .14; .08-.19], travel time [r = .17-.23], and time away [r = .13; .07-.18]) high-intensity running. Cumulative time away was negatively associated with team points (r = -.14; -.28 to -.001) and positively associated with goals conceded (r = .14; .01-.27); no clear association between acute travel metrics and match outcomes or physical performance was observed. As travel cumulated, away teams and their players ran more but for less reward (team points), although the magnitude of these associations was small. These data are exploratory and do not imply acausal relationship; however, further research should consider cumulation of travel.

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.

Association between Hip/Groin Pain and Hip ROM and Strength in Elite Female Soccer Players.

Background/Objectives: Hip strength and range of motion have been compared in soccer players with and without hip and groin pain but only in male footballers or gender-combined samples. In female soccer players, the biomechanics contributing to this injury remain poorly understood compared to other sporting injuries. The aim of the present study is to investigate whether differences exist in adductor and abductor isometric test values and hip joint range of motion between elite female soccer players with longstanding groin pain and injury-free controls. Methods: Ten female elite soccer players with current longstanding hip and groin pain and twenty-five injury-free controls from the same teams were included in the study. Hip adductor and abductor isometric strength were evaluated with a hand-held dynamometer. A bent knee fall-out test was also utilized to examine the hip joint range of motion. Results: A significant difference in abductor isometric test values was observed between the control group (2.29 ± 0.53 N/Kg) and the hip and groin pain group (2.77 ± 0.48 N/Kg; p = 0.018). Furthermore, the injured group showed a decreased adductor/abductor ratio compared to the control group (1.00 ± 0.33 vs. 1.27 ± 0.26; p = 0.013). No differences were observed in the bent knee fall-out test (p = 0.285). Conclusions: Female elite soccer players with current longstanding hip and groin pain exhibited higher abductor isometric strength and lower adductor/abductor ratio compared to non-injured women players. There were no differences in the BKFO test between groups.

“Who’s Got Talent?” Change of Direction, Anthropometric Characteristics and Maturity Offset Differences Between Elite and Sub-Elite Young Soccer Player

ABSTRACT Agility, anthropometrics and maturity-offset have been considered fundamental for talent identification in soccer. The aim of this study is to compare 83 young soccer players (U12) from elite (28) and sub-elite (55) teams, to investigate the influences of anthropometric characteristics and maturation on Change-of-Direction (CoD) with the ball (dribbling) and without the ball. ANCOVA was run to investigate potential differences in Agility T-Test and Shuttle Dribble Test between categories while simultaneously controlling for the effects of anthropometric variables such as Peak Height Velocity (PHV), Weight, and Height. Agility T-Test performance does not significantly differ between the two categories (F-value = 0.537, p > .05). However, the Weight significantly influences the results (F-value = 18.425, p < .001, Eta-Squared = 0.172) and also PHV has a significant impact on them (F-value = 10.099, p < .01, Eta-Squared = 0.094). The Shuttle Dribble Test performance significantly varies between two groups (F-value = 5.207, p < .05, Eta-Squared = 0.057). Only Weight significantly influences this test (F-value = 4.324, p < .05, Eta-Squared = 0.048). Our findings indicate that during the U-12 age period, technical skills emerge as a crucial discriminant factor between elite and sub-elite young soccer players, contrarily to the athletic performance without the ball. In addition, the maturity stage specifically influences the Agility T-Test and Weight is significantly related to lower time to complete both in Agility T-Test and SDT.

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.

Recovery Supplementation Strategies Applied to Elite Soccer Players

Purpose of review: During soccer seasons, athletes have canned a 48 number of matches. Therefore, recovery supplementation strategies that optimize recovery and/or reduce the damage caused by the number of matches during a season are important to help elite football players in their state of recovery. This way, the purpose of this review is to provide a holistic view of the mainly recovery supplements and their effects on elite soccer players recovery, based on what the literature recommends decreasing the oxidative stress, muscle damage and help them in the status recovery. Recent findings: Vitamin C e vitamin E in co-administration (500 mg vitamin C with 1200 IU vitamin E per day), 6 g per day of glutamine supplementation, and 60 mL drinks per day of Turmeric Original Shot (1400 mg curcumin combined with 10 mg of piperine), were able to decrease oxidative stress and lower rates of injury. 1000 mg magnesium citrate twice a day and 5000 IU (international units) cholecalciferol supplement daily were improving the recovery status. Coenzyme Q10 100 mg twice daily and omega 3 (550 mg DHA and 550 mg EPA) proven a reduction in the levels of the muscle-damage marker. Summary: Recovery supplements should include the vitamin's C, E, and D, besides that glutamine, magnesium, and turmeric with piperine to be able supplements to help the elite soccer players recovery, decreasing oxidative stress and rates of injury.

The Role of Athlete Leadership Quality in the Characteristics of Team Resilience in Elite Soccer Teams: A Cross-Sectional and Longitudinal Mediation of Team Identification

We present two studies examining the relationship between athlete leadership quality and team resilience and explored the mediating effect of team identification. In Study 1, 194 soccer players (Mage = 18.50, SD = 4.49) from eight national teams participated. Structural equation modeling showed cross-sectionally that the four types of athlete leadership qualities were positively related to the characteristics of resilience and negatively to vulnerability under pressure. Team identification was shown to be a mediator of these relationships. Study 2, with four different time-points, involved 208 young soccer players (Mage = 16.05, SD = 3.39) from two professional clubs (i.e., La Liga). Cross-lagged panel models revealed that task leadership quality (Times 1–2) was positively related to the characteristics of resilience (Times 3–4) and negatively to vulnerability under pressure (Times 3–4). However, team identification did not mediate these relationships. Therefore, practitioners should consider the perceptions of leader quality to achieve benefits during competition.

The effect of motor control impairment and low back pain on the athletic performance of elite soccer players

The effect of motor control impairment and low back pain on the athletic performance of elite soccer players