Performance In Soccer Players Research Articles

The Effect of Strength and Balance Training on Kinesiophobia, Ankle Instability, Function, and Performance in Elite Adolescent Soccer Players with Functional Ankle Instability: A Prospective Cluster Randomized Controlled Trial

We aimed to implement strength and balance training for elite adolescent male soccer players with functional ankle instability (FAI) to assess kinesiophobia, ankle instability, ankle function, and performance. This cluster randomized controlled trial comprised 51 elite adolescent male soccer players with FAI recruited from six different teams, divided into strength, balance, and control groups (SG, n = 17; BG, n = 17; and CG, n = 17, respectively). The SG and BG underwent strength and balance training sessions three times per week for 6 weeks. Primary outcomes were the Tampa scale for kinesiophobia-17 (TSK) and Cumberland ankle instability tool (CAIT) scores to assess kinesiophobia and FAI, respectively. Secondary outcomes were ankle strength (four directions), dynamic balance, static balance (ellipse, displacement, velocity), and performance (figure 8 and side-hop tests). A significant interaction effect was observed for both TSK and CAIT post-intervention (both, P < 0.01). In post hoc analyses, the BG had significantly better outcomes in reducing TSK. The SG and BG showed greater improvements in CAIT scores. Regression analysis indicated that CAIT severity correlated significantly with TSK (P = 0.039, R = 0.289). For secondary outcomes, the SG and BG were superior in terms of ankle dorsiflexion/inversion strength, static balance displacement, and figure-8 and side-hop tests (all, P < 0.05). The BG showed significantly better static balance ellipse results (P < 0.05). The 6-week intervention significantly enhanced kinesiophobia management, ankle stability, and performance. Balance training effectively mitigated kinesiophobia and improved balance, compared with strength training alone. Even small variations in CAIT severity can influence kinesiophobia, highlighting the potential benefits of balance training. Integrating balance training into training programs can address both physical and psychological aspects of ankle instability. Research is recommended to explore the longitudinal effects of these interventions and their potential to prevent injury recurrence.

How Match-Related Variables Influence the Physical Demands of Professional Female Soccer Players during the Regular Season

To investigate how contextual or environmental factors may influence the athletic performance of female soccer players during competitions, this study aimed to assess the impact of match-related variables (playing surface; opponent levels; opponent result trends; match status, and match outcomes) on the athletic performance of professional female soccer athletes. Seventeen athletes (25.5 ± 4.3 years of age) from the same team competing in the Italian second division were divided into two groups according to their roles and athletic characteristics: Group A (central defenders and forwards) and Group B (right/left full-backs and midfielders). Total distance (TD) and sprint distance (SD); high-speed running (HSR), acceleration (ACC), and deceleration numbers (DEC); average and maximal heart rate (HR_avg; HR_max); and match-related factors were collected during the 22 regular season matches. A T-test and ANOVA were used to calculate the differences between groups in GPS and HR variables and the effects of match-related factors, respectively. Results showed higher running performance in the B group compared to the A group during matches. Increased ACC number was seen in matches played on artificial turf; winning was associated with decreased HR_max and increased DEC number. Athletes covered higher TD reaching lower HR_max when playing against lower-ranking opponents while matches lost/drawn resulted in higher HSR. High HRs (max and avg) were found when playing against a team with a positive performance trend. In summary, match-related factors and opponents’ characteristics can affect athletic performance in female soccer athletes. These factors should be considered during in-seasonal training to personalize match preparation and optimize athlete performance.

An Expected Goals on Target (xGOT) Metric as a New Metric for Analyzing Elite Soccer Player Performance

Introduction. Football analysis is an applied research area that has seen a huge upsurge in recent years. More complex analysis to understand the soccer players’ or teams’ performances during matches is required. The objective of this study was to prove the usefulness of the expected goals on target (xGOT) metric, as a good indicator of a soccer team’s performance in professional Spanish football leagues, both in the women’s and men’s categories. Method. The data for the Spanish teams were collected from the statistical website Football Reference (https://www.fbref.com). The 2023/24 season was analyzed for Spanish leagues, both in the women’s and men’s categories (LigaF and LaLiga, respectively). For all teams, the following variables were calculated: goals, possession value (PV), expected goals (xG) and xGOT. All data obtained for each variable were normalized by match (90 min). A descriptive and correlational statistical analysis was carried out. Results. In the men’s league, this study found a high correlation between goals per match and xGOT (R2 = 0.9248) while in the women’s league, there was a high correlation between goals per match (R2 = 0.9820) and xG and between goals per match and xGOT (R2 = 0.9574). Conclusions. In the LaLiga, the xGOT was the best metric that represented the match result while in the LigaF, the xG and the xGOT were the best metrics that represented the match score.

Brain endurance training improves soccer-specific technical skills and cognitive performance in fatigued professional soccer players

ObjectivesBrain Endurance Training (BET) — the addition of mentally fatiguing cognitive tasks to standard physical training — could improve sporting performance in soccer. We tested whether BET, with cognitive tasks intermixed with physical training activities, improved players' cognitive and soccer-specific technical performance compared to physical training alone when fresh and fatigued. DesignThe study employed a pre/training/midtest/training/posttest design. Methods31 professional male soccer players were randomly assigned to BET or control groups and completed 18 physical training sessions over 6 weeks. In between the physical training activities, the BET group completed demanding cognitive tasks, whereas the control group rested. Players completed the Loughborough soccer passing (LSPT) and shooting test (LSST) before and after completing a 30-min Stroop task. A brief psychomotor vigilance test (PVT-B), a visual analog rating of mental fatigue (MF-VAS), and rating of perceived exertion (RPE) were measured during testing and training. ResultsDuring testing, the 30-min Stroop task elicited a state of MF, confirmed by higher subjective ratings (P < .01). Compared to pre-testing, at mid- and post-testing, the BET group improved passing (all P < .01), shooting (all P < .01), and PVT-B performance (all P < .01) when tested after (fatigued) but not before (fresh) the Stroop task, whereas the control group did not change performance either way. During training the BET group reported higher MF (P < .01) and exhibited slower PVT-B responses (P < .01) compared to control. ConclusionsIntermixed BET was more effective than physical training alone at improving cognitive and soccer-specific technical performance of professional soccer players when fatigued.

Relation of general-perceptual cognitive abilities and sport-specific performance of young competitive soccer players.

In soccer, skill is significantly influenced by motor skills and physical constitution. In addition, perceptual-cognitive abilities are thought to affect sport-specific performance. Nevertheless, there are hardly any studies investigating the relationship of general cognitive abilities with sport-specific performance. Therefore, the aim of this study was to analyze relationships between general perceptual-cognitive abilities and soccer-specific performance in competitive youth sports. Thirty highly talented male youth soccer players aged 12-14years completed various perceptual-cognitive (selective attention, cognitive flexibility, inhibition, working memory, peripheral perception, and choice response) and sport-specific on-field tests. Cognitive abilities were assessed using a computer-based test system. Soccer-specific performance skills were evaluated by two sport-specific on-field tests. The relation between perceptual-cognitive abilities and soccer-specific performance was examined using a correlation analysis as well as a four-stage regression analysis. Overall, the expression of general perceptual-cognitive abilities was found to have an impact on performance in soccer-specific test situations, particularly cognitive flexibility and selective attention. Our results suggest that general cognitive tests could be an important tool for the evaluation of cognitive abilities in soccer. This study brings together key approaches in expertise research and makes a significant contribution to a better understanding of expertise in soccer.

Effectiveness of 12-Week Core Stability Training on Postural Balance in Soccer Players With Groin Pain: A Single-Blind Randomized Controlled Pilot Study.

Core stability training (CST) is effective in improving postural balance, core endurance, and self-reported outcomes in different populations. This study aimed to investigate the effect of CST in soccer players with groin pain (GP). CST would improve postural balance performance, core endurance, and self-reported outcomes in soccer players with GP. Randomized controlled trial. Level 2. Soccer players with GP who met the selection criteria were assigned randomly to a CST (CSTG, n = 10) or a control (CG, n = 10) group. The CG undertook no additional physical activity program besides their usual training. The CSTG performed a 12-week CST comprising 76 ~75 min sessions. Static (force platform) and dynamic (Y-Balance test) postural balance, core endurance (McGill trunk endurance tests), and self-reported outcomes (Copenhagen Hip and Groin Outcome Score [HAGOS]) were assessed before and immediately after the 12-week CST. Significant improvements were seen in dynamic postural balance (P = 0.04 to <0.01), HAGOS scores (P = 0.02 to <0.01), and core endurance measures (P < 0.01) in the CSTG in posttest compared with pretest session and compared with CG. Static bipedal postural balance measures showed significant improvements (eyes open, P = 0.02; eyes closed, P < 0.01) in the CSTG in posttest compared with pretest session. However, no significant differences (P > 0.05) were observed between CSTG and CG after the training period. A 12-week CST improved static (foam surface) and dynamic postural balance, core endurance measures, and HAGOS scores. The beneficial effect of CST on improving postural balance, core endurance, and self-reported outcomes in soccer players with GP suggests that this training would be an important feature of rehabilitation programs for these players. Coaches and clinicians should prioritize CST training when designing rehabilitation programs.

The Effect of Biomechanical and Viscoelastic Properties of Gastrocnemius (Lateral-Medial) Muscle and Achilles Tendon on Jumping Performance in Professional Soccer Players

Anaerobic performance (vertical jumps) is an important indicator in determining athletic performance in soccer. The aim of this study was to investigate the effects of biomechanical and viscoelastic properties of lateral and medial gastrocnemius (LG&amp;amp;MG) muscle and achilles tendon (AT) on jumping performance of professional soccer players. A total of 21 male professional soccer players with a mean age of 18.19±0.40 years, a mean height of 180.48±6.25 cm, a mean body weight of 70.71±7.82 kg, and a mean BMI of 21.66±1.65 kg/m₂ were included in this study. LG and MG muscle, as well as AT biomechanical and viscoelastic properties were evaluated with Myoton Pro device. Measurements were performed in the prone position of the soccer players, LG and MG at 50° plantar flexion, and AT at 0° (neutral position) at an angle of 4 cm above the calcaneal tubercle. Counter movement jump (CMJ) were recorded with the high-speed camera in the validated My Jump 2 application. A significant correlation was observed between the LG (F) tension value and CMJ (P) value and between the MG (R&amp;amp;C) values and the CMJ (F&amp;amp;P) value of professional soccer players (p&amp;lt;0.05). There was no significant relationship between AT values and CMJ values (p&amp;gt;0.05). It should not be forgotten that training coaches on this subject and applying this information to soccer players by conscious coaches will bring about increases in the athletic performance of soccer players, and all these performance characteristics can be achieved with planned and programmed training.

The Effects of Volume-Matched 1- and 2-Day Repeated Backward Sprint Training Formats on Physical Performance in Youth Male Soccer Players.

Bouguezzi, R, Negra, Y, Sammoud, S, Uthoff, A, Moran, J, Behrens, M, and Chaabene, H. The effects of volume-matched 1- and 2-day repeated backward sprint training formats on physical performance in youth male soccer players. J Strength Cond Res XX(X): 000-000, 2024-This study examined the effects of a 6-week, 1 vs. 2 sessions of volume-matched weekly repeated backward sprint training (RBST) on measures of physical fitness in youth male soccer players. Thirty male youth soccer players from a regional soccer team were randomly assigned to a 2-day group (n = 15; age = 16.40 ± 0.64 years; Maturity-offset = 2.19 ± 0.65 years) or a 1-day group (n = 15; age = 16.27 ± 0.51 years; Maturity-offset = 1.91 ± 0.40 years). Measures of jumping ability, linear sprint speed, change-of-direction (CoD) speed, aerobic endurance (AE), and repeated sprint ability (RSA) were measured before and after 6 weeks of training. The training interventions involved 1 to 2 sets, each comprising 7 repetitions over a 20-m distance of RBST in the 2-day group, and 2 to 4 sets, also with 7 repetitions each over the same distance, in the 1-day group. Statistical analyses were conducted using the analysis of covariance model with baseline measurements entered as covariates. Results indicated that RBST over 2 days generated greater benefits compared with a single day for improving CoD speed (∆4.91 vs. 0.04%; effect size [d] = 0.78 vs. 0.00, respectively), linear sprint speed (10-m: ∆4.74 vs. 0.36%; d = 0.96 vs. 0.00, respectively; 20 m: ∆3.34 vs. 0.82%; d = 1.00 vs. 0.49, respectively), and RSA performances (RSAbest: ∆2.61 vs. 0.29%; d = 0.71 vs. 0.16, respectively; RSAmean: ∆2.86 vs. 0.89%; d = 0.59 vs. 0.16, respectively; RSAtotal: ∆2.86 vs. 0.89%; d = 0.62 vs. 0.41, respectively). However, similar improvements in the 2 RBST formats were observed on jumping (2-day group: ∆6.9%; d = 0.75; 1-day group: ∆10.6%, d = 1.26) and AE performance (2-day group: ∆17.24%, d = 1.04; 1-day group: ∆27.25%, d = 2.25). In summary, the findings suggest that, when volume is matched, spreading the RBST regimen over 2 days may result in greater improvements compared with a single-day approach for enhancing CoD speed, linear sprint speed, and RSA performance.

The Effect of Traditional Strength Training on Sprint and Jump Performance in 12- to 15-Year-Old Elite Soccer Players: A 12-Month Controlled Trial.

Skratek, J, Kadlubowski, B, and Keiner, M. The effect of traditional strength training on sprint and jump performance in 12- to 15-year-old elite soccer players: a 12-month controlled trial. J Strength Cond Res XX(X): 000-000, 2024-The aim of the study was to evaluate the effect of traditional strength training on maximum strength (1 repetition maximum in front squat [FS] and back squat [BS]), jump (squat and countermovement jump), and linear sprint (LS) performance (5, 10, and 30 m) in elite young soccer players. A 12-month longitudinal design was chosen, and 48 elite male youth soccer players (age: 12-15 years) were included. The subjects were divided in 2 groups (a strength training group [STG] and a control group [CG]). The intervention group trained for 1 year over a competitive soccer season with additional sessions to their regular soccer practice (4 sessions per week), while the CG did not complete any additional sessions to the regular soccer training (4 sessions per week). The additional strength training (2 sessions per week [each approximately 30 minutes]) consisted of either parallel FS or BS. The squat variants switched in each session. Data were analyzed using a 2 × 3 (group × time) repeated-measures analysis of variance. The main findings of this study were that the STG resulted in significant pretest and post-test improvements in maximum strength (d = 3.75-5.58), jump (d = 0.84-1.14), and LS performance (d = -0.25 to 0.44), while for the CG, smaller increases or performance decreases were measured (maximum strength: d = 1.64-2.7; jump: d = 0.12-0.31; sprint: d = 0.00-025). A significant interaction effect in all variables indicated significant (p < 0.05) stronger performance improvements compared with the CG. Traditional strength training in elite youth soccer players is recommended to increase strength and speed-strength (jump and sprint performance) and should be considered in long-term athletic development programs.

Effects of Specific Dual Task Training on Change of Direction Ability, Cognitive Flexibility, and Inhibition in Young Soccer Players.

In the current study we aimed to investigate the effect of specific dual task training (SDTT) compared to conventional soccer training (CST) on motor and cognitive performances in U13 elite soccer players. Twenty-four young soccer players (all males) participated in this study. We measured their change of direction ability (CODA) and cognitive performances (cognitive flexibility and inhibition) before and after four weeks in either the SDTT group or the CST group. We administered the Trail-Making Test (TMT) to evaluate cognitive flexibility and the Stroop test to evaluate cognitive inhibition. We assessed CODA using the t test (TT). After training, CODA (p < .001), cognitive flexibility (p < .001), and inhibition (p < .001) were improved only in the SDTT group. These results suggest that SDTT seems more suitable than CST to optimally improve both CODA and cognitive performances in U13 elite soccer players.

Performance in professional soccer players: normative data and benchmarks from official matches for metabolic power and high-intensity activities.

The opportunity to compare data among players using normative data and benchmarks may represent a helpful tool for coaches to assess the players' physical performance easily and quickly. This study aimed to create normative data and benchmarks that can be exploited to compare professional soccer players' physical capacity competing in the Premier Division Championship (series A). Match data from six professional soccer teams competing in the Premier Division championship (Serie A and Italy Cup matches) were collected during the entire season. Players (N.=112) were divided based on the role positioning as follows: forwards and wingers (FW), midfielders (MF), side-backs (SB), and center-backs (CB). All the teams analyzed competed with a 4-3-3 formation, and only players who played for the entire match (85-95 minutes) were considered. The video analysis system STATS SportVU was used to collect the data during official matches. Average metabolic power (AP) was considered to estimate the energy cost. The number of power events (PE), distance (m) covered at more than 25 W/kg (D25), and finally, the distance covered at v>25 km/h (VHS) were considered as high-intensity assessments. Standardized T-scores (scaled from 0 to 100) were calculated for each role and variable. T-score data was used to create performance bands combined with qualitative description (ranging from extremely poor to excellent), and a traffic light system approach was implemented to simplify the data's interpretation. The results could be used to compare different athletes' performance quickly and effectively, to detect symptoms of overtraining, and to give helpful insights to coaches on what the training should be focused on.

Effects of muscle fatigue on quadriceps muscle performance in healthy amateur soccer players

IntroductionQuadriceps femoris muscle (QFM) fatigue has a detrimental impact on athlete performance. Therefore, it is crucial to evaluate various performance parameters under fatigued conditions. This study aimed to assess the performance of the QFM during both concentric and eccentric contractions before and after fatigue in the lower extremities of healthy amateur soccer players. MethodTwenty-four healthy amateur soccer players performed three consecutive knee extension and flexion movements concentrically and eccentrically at a velocity of 120°/s with maximum effort, using a Biodex dynamometer. Fatigue was induced by a protocol involving repetitive concentric knee extension and flexion movements at 120°/s, with a load of 50% of maximal voluntary isometric contraction (MVIC) of the QFM until its moment declined to 50% of MVIC. Separate 2-way analyses of variance were conducted to assess the influence of contraction and fatigue on various isokinetic parameters. ResultsNo significant interaction effect between contraction and fatigue was observed for any of the parameters. There was a significant main effect of fatigue on average power for both lower extremities. However, no significant main effect of fatigue was observed for normalized peak moment, angle of peak moment, moment at 0.2s, total work, acceleration, and deceleration times. In contrast, significant main effects of contraction were noted for normalized peak moment, moment at 0.2s, average power, acceleration, and deceleration times in both lower extremities. ConclusionAverage power appeared as the most sensitive performance parameter to fatigue. To enhance QFM performance, emphasizing eccentric exercises during training and conditioning programs could be beneficial for athletes.

The effect of post-match fatigue on physical performance in adolescent soccer players.

Soccer involves many physically challenging actions and engaging in such activities can induce a decline in performance due to physical fatigue which predisposes players to develop injuries. The present study aimed to examine the impact of post-match fatigue on functional performance and Inter-Limb Asymmetry Index (LSI) in adolescent soccer players. Thirty-eight adolescent male soccer players (15-18 years) completed a battery of functional performance measures (Rate of Perceived Exertion (RPE) scale, 10 m sprint, agility T-test, and Single leg hop for distance (SLHD) test). The data collection started prior to a soccer match and consisted of two testing sessions; two hours before the match, while the subsequent testing session was performed within two hours immediately following the match. The study results revealed a significant effect of post-match fatigue on change of direction abilities and SLHD (moderate effect size). However, no significant differences were observed in the 10 m sprint test and LSI (P>0.05). Functional performance measures such as agility test and SLHD test can detect physical ability changes due to post-match fatigue in adolescent soccer players. The study findings offer insightful and practical information on the importance of employing field-based functional performance measures in monitoring players' recovery following a game.

Transcranial Direct Current Stimulation (tDCS) on Soccer Players: A Mini-Review

Background: This mini-review explores the application of Transcranial Direct Current Stimulation (tDCS) in enhancing cognitive and motor performance in soccer players. This review synthesizes findings from recent studies focusing on tDCS’s impact on the primary Motor Cortex (M1) and the Dorsolateral Prefrontal Cortex (dlPFC). Results: studies conducted to date show that tDCS can enhance muscle strength, reduce perceived fatigue, and improve well-being in soccer players. For instance, anodal tDCS applied to the primary motor cortex has been shown to temporarily increase quadriceps strength, while stimulation of the dlPFC has improved recovery post-match and enhanced cognitive functions like reaction time and implicit motor learning. Conclusion: the mini-review highlights the need for more targeted research, emphasizing the importance of individualized protocols and advanced neuroimaging techniques to better understand tDCS’s mechanisms and optimize its use in sports. Future directions suggest adopting neurocircuit-based strategies such as RDoC to tailor interventions more precisely to athletes’ needs. This integration could potentially maximize the benefits of tDCS, offering a holistic approach to enhancing athletic performance and recovery in soccer players.

Effects of textured insoles on dynamic balance and ankle muscle activity in soccer players with and without chronic ankle instability.

Chronic ankle instability (CAI) poses challenges in sports. Textured insoles (TI) are a promising intervention for enhancing dynamic balance in CAI athletes. This study aimed to investigate the effects of TI on dynamic balance performance and ankle muscle activity in soccer players with and without CAI. Thirty-eight soccer players (19 CAI, 19 non-CAI) participated. Participants performed a modified star excursion balance test (mSEBT) while wearing TI and standard insoles (SI). The %SEBT reach distance and electromyography (EMG) activity of tibialis anterior (TA), medial gastrocnemius (MG), and peroneus longus (PL) were measured during maximum reached in each direction of the mSEBT. No significant effects or interactions were found between ankle conditions (CAI vs. non-CAI) or insole types (TI vs. SI) on %SEBT reach. However, CAI players showed greater MG activity in posteromedial and posterolateral direction (P=0.04, P=0.01). Overall, the application of TI did not have immediate effects on dynamic balance performance or ankle muscle activity in either CAI or non-CAI soccer players. Nonetheless, CAI players seemed to employ a different ankle strategy involving the MG muscle, possibly to control stability during dynamic movement, particularly in the posteromedial and posterolateral directions.

Effects of Fast-Tempo and Binaural Beat Therapy Music during Warm-Up on Repeated Sprint Ability Test Performance among Young Soccer Players.

This prospective crossover study aimed to investigate the effect of binaural beat therapy music on soccer player performance. Between July 2023 and December 2023, 45 athletes (31 females/14 males, mean age = 20.47 ± 0.99) wore Bluetooth earphones through which one of the following was given during initial 20 min warm-up exercises before undergoing repeated sprint ability tests: no music/fast-tempo music/fast-tempo music with background binaural beat therapy music. Heart rate change after warm-up exercises/repeated sprint ability (RSA) tests and the time to finish RSA tests were recorded. Despite no significant difference in heart rate increase after warm-up between the two genders regardless of intervention, larger increases after RSA tests were found in males following any of the three interventions (all p < 0.01) with the most notable difference observed after fast-tempo music (p < 0.0001). A significant effect size (r = 0.2) correlated with fast-tempo music during warm-up in either gender. Binaural beat therapy music during warm-up reached a significant effect size only when all participants were considered, suggesting limited benefits.

Norwegian male U14 soccer players have superior running capacity compared to Icelandic players.

The organisation and development strategies of youth soccer differ between Norway and Iceland. Whether this affect physical capacity is unknown. Thus, the first aim of the present study is to compare physical capacity between players from Iceland and Norway. Secondary aim is to assess associations between biological maturity and physical capacity in the Icelandic players since an association previously has been shown among the Norwegians. There were 48 U14 players from Iceland included and 103 players from Norway. Bone age (BA), measured with left-wrist x-ray, was used as an indicator of biological maturity. To measure physical capacity, 40 metre (m) linear sprint, standing long jump (SLJ), countermovement jump (CMJ), the Yo-Yo intermittent recovery test (IR1-test) and a maximal oxygen uptake test (VO2max) were used. Training load was assessed by questionnaire. The results showed that the Norwegian players ran faster (5.90 ± 0.38 vs. 6.37 ± 0.44 s, p < .001), had better intermittent endurance capacity (1,235 ± 461 vs. 960 ± 423 m, p < .001) and higher VO2max, (60.3 ± 6.5 vs. 54.8 ± 5.3 ml·kg-1·min-1, p < .001) than the Icelandic players. The players from Norway reported a higher number of weekly organised soccer training hours than the Icelandic. We also found significant correlations between BA and performance on 40 m linear sprint (r = -.566, p < .001), SLJ (r = .380, p = .008) and CMJ (r = .354, p = .014) among the Icelandic players. Moreover, no correlations were found between BA and VO2max or intermittent endurance capacity. In conclusion, the Norwegian players ran faster and had better VO2max and intermittent endurance capacity than the Icelandic players. Biological maturity level was associated with speed and jumping performance in U14 soccer players in Iceland, but not with VO2max or intermittent endurance capacity. Findings indicate that more research is needed to investigate the influence of different organisation and structure of youth soccer between the two countries on physical capacity.

Light load jump squat and plyometric training enhance jumping, sprinting, change of direction, and balance performance of male soccer players (U-19): a randomized controlled trial.

In sports science, optimizing athletic performance is pursued through an emerging approach that combined light-loaded squat (LLS) training and plyometric jump training (PJT), targeting strength, power, and neuromuscular adaptations, particularly beneficial for the dynamic demands of youth soccer. The aim of this study was to examine the effect of a combined LLS training and PJT program on athletic performance and balance in youth soccer players. Thirty-two male players were randomly assigned to two groups: an experimental group (EG: N.=16; age: 18.56±0.51 years; body mass: 66.87±4.99 kg; height: 1.78±0.07 m) and a control group (CG: N.=16; age: 18.68±0.47 years; body mass: 67.93±4.58 kg; height: 1.77±0.07 m) from the same U19 team of a professional club voluntarily participated in the study. Squat jump (SJ), countermovement jump (CMJ), horizontal jump (HJ), drop jump (DJ), 30 m sprint (30 mS), change of direction ability (4×5 m sprint test [S 4×5 m]) and static balance (the stork balance) performance tests were carried out in the week before and the week after the 8 weeks with combined LLS and PJT period. The two-way analysis of variance (ANOVA) was used for all tests. The results of this study show that the EG had significantly greater improvements than the CG in all tests (all P<0.001). Also, EG experienced higher performance between preintervention and post intervention measures (all P<0.05). There was no significant difference between the two groups in the 4×5mS performance (P>0.05). We conclude that coaches may be advised to use the combined LLS and PJT since it is as effective as traditional methods and perfect for sports and activities requiring fast, explosive movements during the in-season period than regular training.

Effects of Acute Ingestion of Guarana (Paullinia Cupana) on Soccer Player Performance: A Randomized, Cross-over, Placebo-Controlled Study

Objective To investigate the acute effects of ingesting a beverage containing guarana (Paullinia cupana) seed powder on performance during field tests related to physical capacities that are determinants of soccer performance, such as lower limb power, sprint, agility, and the capacity to carry out intermittent exercise. Methods The study was conducted using a randomized, crossover, and counterbalanced design, with a beverage containing guarana or placebo administered in a double-blind manner. Twenty-seven under-17 soccer players of a professional soccer club performed a battery of tests 60 min after the ingestion of guarana (3 g of the fruit seed powder) or placebo. Trials were performed with a 7-day washout period. The battery of tests included a countermovement jump test, sprints of 10 and 20 m, an Illinois agility test, and a Yo–Yo Intermittent Recovery Test level 1 (YYIR1). Results Guarana ingestion did not improve countermovement jump, sprints, or agility (p > 0.05). However, guarana ingestion increased the distance covered in the YYIR1, compared with placebo ingestion (p = 0.01). Conclusion Acute ingestion of guarana improves the capacity to perform intermittent exercise in soccer players but seems to be ineffective to improve lower limb power, sprint, and agility.

Physical performance in young female football athletes: a systematic review

The objective was to analyze the physical performance in female soccer players. A systematic review was performed by searching MedLine (PubMed), SPORTDiscus, Web of Science, ScienceDirect, Scopus, Lilacs (BVS) and SciELO databases for observational studies performed on female soccer players under 18 years of age, who underwent neuromuscular and/or cardiorespiratory physical testing. Of the 934 studies found, 19 were included. The sample size in the studies ranged from 11 to 499 players, with total of 1879 athletes, aged between 9 and 17 years. Neuromuscular tests were more used than cardiorespiratory ones. In conclusion, jumps, linear velocity and change of direction were more used in the context of soccer played by women to determine performance in young athletes. However, cardiorespiratory capacity tests were used to a lesser extent, with a predominance of the level 1 yo-yo intermittent recovery test (YYIR1).