Soccer Training Research Articles

The Effects of a Visual Stimuli Training Program on Reaction Time, Cognitive Function, and Fitness in Young Soccer Players.

The purpose of the present study was to examine whether a visual stimuli program during soccer training can affect reaction time (RT), cognitive function, and physical fitness in adolescent soccer players. Thirty-eight male soccer players aged 10–15 were randomly assigned to either the intervention (Group A) or the control group (Group B). At baseline and at the end of the 6-month study FITLIGHT Trainer, the Cognitive Function Scanner Mobile Test Suite, a Virtual Reality (VR) game, and the ALPHA—Fitness and the Eurofit test batteries were used to measure participants’ abilities. After the baseline assessment, Group A followed their regular soccer training combined with a visual stimuli program, while Group B continued their regular soccer training program alone for 6 months. At the end of the 6-month study, Group A showed statistically significant improvements in simple RT by 11.8% (p = 0.002), repeated sprints by 13.4% (p ≤ 0.001), and Pen-to-Point Cognitive Function by 71.62% (p < 0.001) and 72.51% for dominant and non-dominant hands, respectively. However, a between-groups analysis showed that there was no statistically significant difference between the two groups in most of the measurements studied. In conclusion, a visual stimuli training program does not seem to add any value to the traditional soccer training program for adolescents. Nevertheless, this study helps to underline the potential of newly emerging technology as a tool for the assessment of RT.

Anthropometric and Physiological Profiles of Hungarian Youth Male Soccer Players of Varying Ages and Playing Positions: A Multidimensional Assessment with a Critical Approach.

Background: This study aimed to create preliminary anthropometric and physiological profiles of Hungarian male soccer players belonging to different age categories (14, 15, 16, and 17–18-years) and assigned to different playing positions (forward, defender, midfielder, goalkeeper). Methods: Anthropometric and physiological profiles were created for four age groups: 14- (n = 20), 15- (n = 16), 16- (n = 22) and 17–18-year-olds (n = 23) representing the Hungarian soccer academy. Additionally, the variables were analyzed across the four player positions mentioned above. Results: The mean values of body mass, fat mass and BMI were within normal limits, although in some cases the anthropometric and body composition values were too high, particularly among the 17–18-year-olds. The mean values of HRrest were lowest among the 15-year-olds. The highest mean and maximal values of rVO2max and rVO2/AT [57.6 ± 8.12 (43.8–68.3) and 51.2 ± 7.24 (38.9–60.8) mL/kg/min, respectively] were noted in 14-year-olds. Goalkeepers performed significantly better than the remaining soccer players in terms of the most anthropometric and physiological characteristics, except for the Yo-Yo test (p < 0.001). Conclusions: The values of anthropometric parameters increased with age. As expected, the oldest group achieved the best results in the performance tests. Goalkeepers outperformed the players representing other playing positions in the tests when assessing lower limb strength, sprint performance (5- and 10-m distance), and agility tests. From a practical point of view, the presented anthropometric and physiological profiles of players representing different age groups and playing positions can be useful for soccer coaches, strength and conditioning specialists, and athletic trainers of other soccer clubs in terms of the individualization and optimalization of soccer training.

Perceptions Of Monitoring Techniques For Fatigue Used By Strength Coaches On NCAA Women's Soccer Players

NCAA Division II women soccer athletes may experience high levels of fatigue which can have a negative impact on their performance during competition. Although coaches agree that monitoring fatigue is an important element in program design, there is not one widely accepted fatigue measure used to monitor women’s soccer training. PURPOSE: To provide an investigation on the preferred mode of action by strength and conditioning coaches to reduce fatigue and increase performance of NCAA Division II women’s soccer players. METHODS: Eight (n = 8) head strength and conditioning coaches, two (n = 2) women’s soccer coaches, and eighteen (n = 18) women’s soccer players from the NCAA Division II PSAC participated in this retrospective qualitative case study from the fall 2019 semester. Strength and conditioning coaches and head women’s soccer coaches participated in a semi-structured interview while women’s soccer players completed an open-ended survey to share their insights to examine the current fatigue monitoring techniques utilized at the NCAA Division II level with all information subsequently analyzed thematically to code the data. RESULTS: All strength and conditioning coaches interviewed believed monitoring fatigue is important (100%) yet only a select number of coaches are currently implementing such fatigue monitoring techniques (38%). Of the fatigue techniques currently being implemented, the women’s soccer players believed the programs did help reduce fatigue (72%) and increase performance (78%). Thematic analysis of the barriers that strength and conditioning coaches face to implement a fatigue monitoring program were also identified which include limited staff, budget, and facilities at the NCAA Division II level. CONCLUSION: With the wide range of fatigue monitoring techniques available, selection and implementation of the most appropriate test based on the various factors at each specific university can provide an effective and productive system to garner the most out of each athlete during training and competition.

An exploratory study on the effect of a four-week stroboscopic vision training program on soccer dribbling performance

BACKGROUND: Perceptual-cognitive skill is a crucial component of expert performance in sport as expert athletes rely on the integration and processing of sensory information to execute complex actions. One of the topics of interest to skill acquisition researchers is therefore how the perceptual-cognitive system can be trained, and how that affects sport skill performance. One of the methods suggested to be able to aid in the training of perceptual-cognitive skill is restricted visual feedback training. Recently, stroboscopic vision glasses have been proposed as a tool that can restrict visual feedback during sport training and may therefore provide a useful tool for training sport-specific skills.However, despite its use in practice, evidence for the beneficial effect of stroboscopic vision on sport-specific performance across youth athletes with a range of performance levels is currently lacking. AIM: Therefore, this study aimed to investigate the effect of a four-week soccer training program with (experimental group) or without (control group) stroboscopic vision on the dribbling performance of relatively fast and slow dribblers. METHOD: To measure dribbling performance, this study used the Ugent Soccer dribbling task. RESULTS: A Repeated Measures MANOVA revealed that four weeks of stroboscopic vision training did not improve soccer dribbling skill measured through the time taken to complete the dribbling task as well as the number of touches of the ball while dribbling. CONCLUSION: While stroboscopic vision can likely lead to short term changes in perceptual-cognitive skill, it is likely not related to persistent changes in soccer dribbling performance in youth soccer players.

Four Weeks of Power Optimized Sprint Training Improves Sprint Performance in Adolescent Soccer Players.

This study compared the effects of heavy resisted sprint training (RST) versus unresisted sprint training (UST) on sprint performance among adolescent soccer players. Twenty-four male soccer players (age: 15.7 [0.5]y; body height: 175.7 [9.4]cm; body mass: 62.5 [9.2]kg) were randomly assigned to the RST group (n = 8), the UST group (n = 10), or the control group (n = 6). The UST group performed 8 × 20 m unresisted sprints twice weekly for 4 weeks, whereas the RST group performed 5 × 20-m heavy resisted sprints with a resistance set to maximize the horizontal power output. The control group performed only ordinary soccer training and match play. Magnitude-based decision and linear regression were used to analyze the data. The RST group improved sprint performances with moderate to large effect sizes (0.76-1.41) across all distances, both within and between groups (>92% beneficial effect likelihood). Conversely, there were no clear improvements in the UST and control groups. The RST evoked the largest improvements over short distances (6%-8%) and was strongly associated with increased maximum horizontal force capacities (r = .9). Players with a preintervention deficit in force capacity appeared to benefit the most from RST. Four weeks of heavy RST led to superior improvements in short-sprint performance compared with UST among adolescent soccer players. Heavy RST, using a load individually selected to maximize horizontal power, is therefore highly recommended as a method to improve sprint acceleration in youth athletes.

Design and Reliability of an Observational Framework to Evaluate the Individual Offensive Behavior in Youth Soccer-The INDISOC Tool.

Despite the great development of match analysis in professional soccer during the last decade, very few studies have assessed the individual technical and tactical behaviors of youth soccer players. The purpose of this paper was to design and assess the reliability of an observational instrument to evaluate the INDIvidual offensive behavior in competitive 7 and 11-a-side SOCcer (INDISOC). A total of eight experts in soccer training and analysis were included in the design of the tool by means of meetings and exploratory observations. This process involved design and re-design steps of the INDISOC tool to its final format which includes twelve dimensions related to the spatial, technical, and tactical constraints of individual behavior in soccer. The unit of analysis was the individual ball possession (IBP), described as the time that starts when a player can perform an action with the ball, and which ends when the IBP for another player begins. In the INDISOC tool, the IBP is analyzed taking into account three temporal moments: (1) receiving the ball, (2) processing the ball, and (3) culminating the individual action. Inter-observer and intra-observer analyses were performed and the kappa (K) coefficients were calculated to test the instrument reliability. The K values showed optimal inter (7-a-side: 0.73–0.95; 11-a-side: 0.76–0.98) and intra-observer (7-a-side: 0.84–1;11-a-side: 0.79–1) reliability levels. These results support the notion that the INDISOC observational tool could be a suitable instrument for analyzing the individual offensive behavior in competitive youth (7-a-side), junior and senior (11-a-side) soccer.

Effectiveness of wearable technology to optimize youth soccer players’ off-training behaviour and training responses: a parallel group randomized trial

ABSTRACT Background Although youth soccer players meet and exceed the weekly physical activity (PA) guidelines also exhibit high off-training sedentary behaviour (SB) levels. Recent evidence indicated that low PA preceding training leads to decreased PA intensity in soccer practice and that SB impairs sports performance and recovery. Thus, a parallel group randomized trial examined the effect of activity wristbands on young players’ off-training PA and SB profiles; assessed the added value of wearable wristbands with PA warnings; and investigated whether manipulating off-training PA can affect the players’ training responses. Methods Thirty-two adolescent soccer players (16.1 ± 0.9 years old) were monitored during weekdays for two weeks (interspersed with one week). Players were randomly assigned to a reminder to move (REM) and a non-reminder to move group (nREM). The REM wore an activity wristband (Fitbit Charge 2) with PA warnings in the last week of research, while the nREM wore identical monitors without PA feedback. Throughout the study, off-training PA was assessed using tri-axial accelerometers, and training responses were analysed using wearable inertial monitoring units. Gardner-Altman estimation plots and a Fisher’s Exact Test of Independence estimated each group’s off-training PA changes between the monitored weeks. Complementary, an analysis of covariance (ANCOVA) quantified the effect of Fitbit wristband configurations (with a reminder to move or without a reminder to move) on the off-training PA and soccer training external load variables. The independent variable group had two levels (REM and nREM). The off-training PA and training load values collected in the first week were introduced in the model as a covariate, the groups were designated fixed factors and the off-training PA and training load from the third week were the dependent variables. The team was also included as a covariate and the between-group differences post-intervention were adjusted for baseline and team. Results Interestingly, results showed that different wearable wristbands did not influence the players’ off-training PA profiles (p > 0.05). Concomitantly, no differences were observed in training responses (p > 0.05). Conclusion Findings emphasize the importance of health and youth sports organizations in developing newer approaches for promoting healthier lifestyles, beyond training practices, with potentially favourable implications for sports performance.

Effects of moderate altitude on the physical performance of elite female soccer players during an official soccer tournament

The aim of this study was to investigate the effects of moderate altitude (2800 m) on neuromuscular performance, body-mass, rating of perceived exertion, total quality recovery, and global positioning system–motion variables (distance covered, sprint distance, number of accelerations, and top-speed) during soccer training and official matches. Seventeen professional female soccer players performed vertical jump tests and were weighed over seven days during the altitude acclimatization. Global positioning system–motion variables, rating of perceived exertion, and total quality recovery were assessed over two training sessions at 2800 m and compared to the metrics collected during two sessions at sea level. Global positioning system–motion variables were measured during six official matches played at 2800 m and compared to six matches at sea level. Vertical jump height and body-mass did not change during acclimatization ( p &gt; 0.05). Rating of perceived exertion was higher and total quality recovery was lower after training sessions at altitude ( p &lt; 0.05). Total distance covered ( p = 0.002), total sprint distance ( p = 0.016), and total distance covered per minute ( p = 0.02) decreased and rating of perceived exertion increased ( p = 0.012) in the matches at moderate altitude compared to sea level. No differences were observed for top-speed and acceleration ( p &gt; 0.05). These findings suggest that moderate altitude can lead to substantial decreases in the physical performance (especially in total sprint distance), increased rating of perceived exertion, decreased total quality recovery in female players. These occurrences are critical to soccer performance.

Distributed Soccer Training Smart Sensors for Multitarget Localization and Tracking

This paper presents an in-depth study and analysis of the localization and tracking of multiple targets in soccer training using a distributed intelligent sensor approach. An event-triggered mechanism is used to drive the acoustic array sensors in the distributed acoustic array sensor network, which solves the problem of increased communication load caused by frequent communication of microphones and effectively reduces the communication load between microphones as well as the energy consumption of the acoustic array sensor network. By designing a suitable state estimation equation for the acoustic source target and fully utilizing the measurement and state estimation information of its nodes as well as the state estimation information of neighboring nodes, the next moment state of the acoustic source target can be accurately predicted. A correlation filtering tracking algorithm based on multiscale spatial co-localization is proposed. In the proposed algorithm, the tracker contains a total of several subfilters with different sampling ranges. Then, this paper also proposes a collaborative discrimination method to judge the spatial response of the target image samples of each filter and jointly localize the target online. Based on this, this paper further explores the potential of correlation filter tracking algorithms in complex environments and proposes a robust correlation filter tracking algorithm that fuses multiscale spatial views. The cross-view geometric similarity measure based on multiframe pose information is proposed, and the matching effect is better than that based on single-frame cross-view geometric similarity; to solve the problem of player appearance similarity interference, a graph model-based cross-view appearance similarity measure learning method is further proposed, with players in each view as nodes, player appearance depth features as node attributes, and connections between cross-view players as edges to construct a cross-view player graph. The similarity obtained by the graph convolutional neural network training is better than the appearance similarity calculated based on simple cosine distance.

CORE VS PLYOMETRIC TRAINING EFFECTS ON DYNAMIC BALANCE IN YOUNG MALE SOCCER PLAYERS

ABSTRACT Introduction: Today, different types and volumes of strength training are used to increase the performance of athletes. However, the effect of this training on dynamic balance in young soccer players is a matter of curiosity. Objective: The purpose of this study is to determine the effects of core and plyometric training on dynamic balance in young male soccer players. Materials and Methods: Eighteen male soccer players between 17 and 18 years of age participated in the study voluntarily. Subjects were randomly separated into three groups: core training group (C, n=6), plyometric training group (P, n=6), and control group (Con, n=6). Group C and P subjects participated in the determined training programs, in addition to soccer training, two days a week for eight weeks. The Con group only continued their soccer training. The Y-balance test (before and after eight weeks) was applied to determine the balance performance of the subjects. Results: After eight weeks of core training, significant differences in anterior (ANT) and posteromedial (PM) balance performance on the dominant side and in ANT, PM, and posterolateral (PL) balance performance on the non-dominant side were observed in group C subjects. The PL and PM balance performance of group P subjects after plyometric training was found to be significantly different on both sides. Conclusion: As a result, it was determined that applying core and plyometric training in addition to soccer training increases dynamic balance. We recommend that trainers and coaches use core and plyometric exercises in their training, as these programs will provide a positive performance increase in balance and gains in muscle strength. Level of Evidence III; Prospective comparative study.

Increased Risk of ACL Injury for Female but Not Male Soccer Players on Artificial Turf Versus Natural Grass: A Systematic Review and Meta-Analysis.

Background:Both natural grass (NG) and artificial turf (AT) are popular playing surfaces for soccer. Biomechanical studies have found increased frictional forces on AT that may lead to anterior cruciate ligament (ACL) injury. The increased risk of ACL injury during soccer in female participants may amplify this effect.Purpose:To systematically review the literature for studies comparing ACL injury risk in soccer players on AT versus NG and to specifically determine whether there were differences in injury risk in male versus female players when considering the playing surface.Study Design:Systematic review; Level of evidence, 3.Methods:A systematic review was performed using PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Three databases were searched for studies with evidence level 1 to 3 that compared the incidence of ACL injuries on AT versus NG in soccer players. Data recorded included study characteristics, sex, competition level, exposure setting (games or practices), turf type, and ACL injury information. Study methodological quality was analyzed using the methodological index for non-randomized studies (MINORS) score, and incidence rate ratios (IRRs) were calculated.Results:Included were 7 articles (3 studying professional soccer, 3 collegiate soccer, 1 youth-level soccer; 4 male cohorts, 2 female cohorts, and 1 male and female cohort; mean MINORS score, 20 ± 0.8). Pooled ACL injury IRRs demonstrated no significant differences in overall ACL injury risk when playing soccer on AT compared with NG (IRR = 0.57 [95% CI, 0.21-1.53]; P = .31). A significantly increased risk of ACL injury in games played on AT compared with NG was detected for female (IRR = 1.18 [95% CI, 1.05-1.31]; P = .004) but not for male players (IRR = 1.18 [95% CI, 0.97-1.42]; P = .09). Subgroup analyses showed no significant differences in injury risk for games (IRR = 1.07 [95% CI, 0.97-1.18]; P = .20) or practices (IRR = 0.21 [95% CI, 0.04-1.23]; P = .09).Conclusion:Findings indicated that female soccer players had a significantly higher risk of ACL injury when playing games on AT versus NG, whereas no significant difference was seen in male players. No differences were found for the combined male/female cohort or for soccer games or training sessions played on AT compared with NG.

Coordination variability reduced for soccer players compared to non-athletes during the stance phase of gait.

Soccer is a unilateral sports activity that may alter the spatiotemporal characteristics of gait. This may alter motor control of gait in the dominant leg in soccer players and lead to a sport-specific gait pattern, which has not yet been considered. We aimed to determine whether soccer players exhibit differences in the lower extremity coupling variability during gait compared to healthy non-athletes. Hip, knee, and ankle joint angles from fourteen soccer players and sixteen controls were acquired during treadmill walking. Hip-knee coupling, knee-ankle coupling and coupling angle variability (CAV) of the right leg in the sagittal plane were assessed using a vector coding technique. Soccer players showed reduced hip-knee CAV during the mid-stance and terminal-stance phases of gait compared to the control group (P<inf>adj</inf> =0.04 and P<inf>adj</inf> <0.001, respectively). In addition, soccer players less often used an ankle coordination pattern, in which only the ankle joint but not the knee joint rotates (P<inf>adj</inf> =0.01). In summary, soccer players show altered gait dynamics during normal walking, possibly due to intense soccer training. These changes provide evidence of adaptive strategies of the motor control system to sports activities that can be used for gait rehabilitation. Clinicians should note that some sport, such as soccer, may result in sport-specific gait patterns However, further works are needed to confirm this finding.

Soccer Scoring Techniques-A Biomechanical Re-Conception of Time and Space for Innovations in Soccer Research and Coaching.

Background: Scientifically, both temporal and spatial variables must be examined when developing programs for training various soccer scoring techniques (SSTs). Unfortunately, previous studies on soccer goals have overwhelmingly focused on the development of goal-scoring opportunities or game analysis in elite soccer, leaving the consideration of player-centered temporal-spatial aspects of SSTs mostly neglected. Consequently, there is a scientific gap in the current scoring-opportunity identification and a dearth of scientific concepts for developing SST training in elite soccer. Objectives: This study aims to bridge the gap by introducing effective/proprioceptive shooting volume and a temporal aspect linked to this volume. Method: the SSTs found in FIFA Puskás Award (132 nominated goals between 2009 and 2021) were quantified by using biomechanical modeling and anthropometry. Results: This study found that players’ effective/proprioceptive shooting volume could be sevenfold that of normal practice in current coaching. Conclusion: The overlooked SSTs in research and training practice are commonly airborne and/or acrobatic, which are perceived as high-risk and low-reward. Relying on athletes’ talent to improvise on these complex skills can hardly be considered a viable learning/training strategy. Future research should focus on developing player-centered temporal-spatial SST training to help demystify the effectiveness of proprioceptive shooting volume and increase scoring opportunities in soccer.

Physical Development Differences between Professional Soccer Players from Different Competitive Levels

In soccer, physical development is crucial for developing optimal performance. This study aimed to assess and compare the physical development of elite and non-elite professional soccer players. Seventy-eight male professional football players divided into four competitive levels participated in this study: the elite group (EG), the non-elite group A (NEG-A), the non-elite group B (NEG-B), and the under 23 group (U23). Body composition, static strength, lower-body explosive strength, flexibility, and balance were assessed. No significant statistical differences between elite and non-elite players were seen in body composition parameters. However, the EG performed better in static strength, lower-body explosive strength, flexibility, and balance, even after adjusting for the effects of chronological age. The analysis showed that the competitive level (group) explained 25% to 29% of the variance observed in the lower-body explosive strength tasks. Sports staff and coaches in different age categories or competitive levels should include specific lower-body explosive strength content during soccer training to promote players’ long-term development towards the elite level.

Poster 250: Increased Risk of Anterior Cruciate Ligament Injuries for Female but Not Male Soccer Players on Artificial Turf Versus Natural Grass: A Systematic Review and Meta-Analysis

Objectives:Both natural grass (NG) and artificial turf (AT) are popular playing surfaces for soccer. Biomechanical studies have found increased frictional forces on artificial turf that may lead to anterior cruciate ligament (ACL) injury. Few studies have examined the differences between ACL injury risk in male and female soccer athletes playing on AT versus NG. Given the higher risk for female ACL injury in sports, and soccer in particular, it is important to define whether AT may compound this injury risk. The purpose of this investigation was to systematically review the literature for studies comparing ACL injury risk on AT versus NG in soccer, and to specifically determine if there were differences in injury risk in males versus females when considering the playing surface.Methods:A systematic review was pre-registered on PROSPERO and performed using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. PubMed, SCOPUS, and Cochrane Central Register of Controlled Trials were searched for Level I-III studies that compared the incidence of ACL injuries on AT versus NG in soccer players. Data recorded included study demographics, sex, competition level, exposure setting (games or practices), turf type, and ACL injury information. Study methodological quality was analyzed using the Methodological Index for Non-Randomized Studies (MINORS) score. Incidence rate ratios (IRRs) were calculated by dividing the incidence of ACL injury on AT over NG, where IRRs < 1 indicate a lower incidence of ACL injuries on AT compared to NG, and IRRs > 1 signify a higher incidence of ACL injuries on AT compared to NG. A Mantel-Haenszel random effects model was used for meta-analyses of IRRs, and forest plots were generated for the pooled IRR for ACL injuries in game and training settings. Additionally, sub-analyses based on athlete sex were conducted for IRRs of ACL injuries in games. A p-value of less than 0.05 was set as significant.Results:Seven articles (four male, two female, one male and female cohort; mean MINORS score 20 + 0.8) were included and analyzed (Figure 1). There were two studies that investigated ACL injuries in a female only cohort, four studies that used a male only cohort, and one study that included both males and females (Table 1). Levels of play included professional (n = 3 studies), college (n = 3 studies), and youth (n = 1 studies). Pooled ACL injury IRRs demonstrated no significant differences in overall ACL injury risk when playing soccer on AT compared to NG (IRR = 0.61 [0.23-1.60], p = 0.31; Figure 2). A significantly increased risk of ACL injury in games played on AT compared to NG was detected for females (IRR = 1.18 [1.05-1.31], p = 0.004) but not for males (IRR = 1.18 [0.97- 1.42], p = 0.09; Figure 3). Subgroup analyses showed no significant differences in injury risk for games (IRR = 1.07 [0.97- 1.18], p = 0.20) or practices (IRR = 0.21 [0.04-1.23], p = 0.09; Figure 2). A total of 3,023 ACL injuries occurred on NG and 526 ACL injuries happened on AT, and the majority of soccer exposures in each study was on NG (range: 50.33% - 85.74%).Conclusions:.This investigation found that females had a significantly higher risk of ACL injury when playing games on AT versus NG, whereas no significant difference was seen in males. No differences were found for the combined male/female population nor soccer games or training sessions played on AT compared to NG.Figure 1.Flow diagram summarizing the literature search, screening, and review.Figure 2.Forest plot of the pooled incidence rate ratios {IRRs) for anterior cruciate ligament (ACL) injury on artificial turf (AT) versus natural grass (NG) in soccer players with sub-analysis by exposure setting (game versus training). CI - Confidence IntervalFigure 3.Forest plot of the sub-analysis based on sex (male or female) of pooled incidence rate ratios (IRRs) for anterior cruciate ligament (ACL) injury in soccer games played on artificial turf (AT) versus natural pass (NG). CI - Confidence IntervalTable 1.Summary of study demographics for included articles. MINORS - Methodological Index for Non-Randomized Studies; BJSM - British Journal of Sports Medicine, AJSM - American Journal of Sports Medicine; KSSTA - Knee Surgery, Sports Traumatology, Arthroscopy; OJSM - Orthopaedic Journal of Sports Medicine; SJMSS -Scandinavian Journal of Medicine & Science in Sports; NS - Not Specified

The Effect of Sportsmetrics on the Performance and Knee Valgus During Landing of Female Soccer Players

Purpose: Dynamic knee valgus and poor technique during landing are not only key risk factors for lower extremity injuries especially knee injury, but also can reduce the performance of athletes in the field. Sportsmetrics soccer training is one of the successful knee injury prevention and enhancement performance protocols for female soccer players. Because the effect of sportsmetrics soccer training has not been investigated on the performance and knee valgus during landing in female soccer players, we aimed to investigate this subject. Methods: The current field-trial study was conducted on 24 female soccer players with dynamic knee valgus that were randomly divided into two groups: the training group (TG) and the control group (CG). The assessment tests were the agility t-test, 40-yard test, vertical jump test, double leg squat test, and valgus landing error scoring system test (LESS). The TG group participated in sportsmetrics soccer training regularly for 6 weeks, three 90-min sessions a week. Analysis of covariance was used to analyze the obtained data (P&lt;0.05). Results: Six weeks of sportsmetrics soccer training in the TG group not only reduced dynamic knee valgus during landing (51% reduction, F=171.8, P=0.01) but also improved performance factors significantly: agility (0.50 s reduction, F=23.29, P=0.01), power (2.50 cm increase, F=13.20, P=0.01) and speed (0.30 s reduction, F=23.66, P=0.01). Conclusion: Sportsmetrics soccer training is strongly suggested for soccer players exposed to knee injuries due to dynamic knee valgus during landing.

PENGEMBANGAN ALAT BANTU JUGGLING DAN HEADINGPADA ATLET SEPAKBOLA SSB KOTA MEDAN TAHUN 2021

The purpose of this research is to find out: 1) Creating Juggling and Heading exercise aids. 2) To assist the trainer in carrying out the training process. 3) To assist athletes in carrying out the Juggling and Heading training process in football. The population in this study were 10 athletes from the SSB Tasbi club, 10 athletes from the SSB Mutiara club, and 10 athletes at the SSB Gumarang club. Heading and juggling training aids were first validated by 3 experts, 1 expert in tools/media, 1 trainer expert and 1 sports expert, where the average value of the validity presentation was 94.6%. and sports experts get a “Good/Decent” category. The method used is the research and development (R&amp;D) method of Sugiyono. The results of a small group trial involving 10 SSB Tasbi athletes concluded that the development of Juggling and Heading aids in this study obtained a percentage of 30% - 40%, the eligibility category was lacking and must be improved. The results of the large group trial involving 10 athletes from the SSB Gumarang Club, and 10 athletes from the Mutiara SSB Club that the development of juggling and heading aids obtained a percentage of 76% - 87%, the eligibility category was good and could be used in assisting the soccer training process. From the results of tool validation, small group trials and large group trials, it can be concluded that juggling and heading aids are needed in training at SSB Tasbi, SSB Gumarang, SSB Mutiara clubs and make it easier for coaches in the process of training juggling and heading for beginner athletes. with the form of a portable tool that makes it easier to use and increases the interest of athletes to continue to improve their training.

The effect of eight weeks beetroot juice supplement on aerobic, anaerobic power, and field performance of soccer players

ABSTRACT The purpose of the study investigated the effect of eight weeks of soccer training with beetroot juice supplement on aerobic power, anaerobic power, and field performance of soccer players. This is experimental research, by the control group in pre and post-test. The statistical population was male soccer players. Forty subjects were randomly divided into four groups including the exercise group (EX) the exercise group with beetroot juice supplement (EX&BRJS) the beetroot juice supplement group (BRJS), and the control group (C). Aerobic power, anaerobic threshold, and respiratory exchange ratio, measured by the gas analyser (Cosmed), anaerobic power (peak, mean power), and fatigue index, by Wingate cycle test (Monark, 839), and field performance by (Bangsbo, field test performance). The statistical methods include the Kolmogorov-Smirnov, Levin, covariance (ANCOVA), and pair comparison with Bonferroni test. The results showed eight weeks’ of soccer training with beetroot juice supplement, significantly changed aerobic power, respiratory exchange ratio, anaerobic threshold, anaerobic power, field performance, and fatigue index (P ≤ 0.05). Additionally, in all variables, the paired comparison showed that the EX&BRJS group progressed more than all other condition groups. The soccer athletes may use beetroot juice supplements along with soccer exercises to improve aerobic and anaerobic power and field performance.

PENGEMBANGAN ALAT LATIHAN SEPAK MULA (SERVICE) PADA PERMAINAN SEPAK TAKRAW

The purpose of this research isto develop a product of a soccer trainingtool (service) in the game of sepak takraw which functions to make theinitial soccer technique (service) effective, efficient and help thecoach's work in providing soccer technique material (service) becomeeasier. This research is a development research with several stages,namely, from potential and problems, data collection, product design,expert validation, expert validation, product revision, product testing,usage trials, and final results. Validation results from 1 material expert,1 practitioner expert, 5 respondents as small-scale trials and 17respondents as large-scale trials. From the results of this study it canbe seen that "Development of Soccer Training Tools (Service) inSepak Takraw" can be categorized as Eligible from the assessment ofmaterial experts 93.33 and expert practitioner assessments 97.5 as wellas assessments from small-scale trials 90.18% and assessment of theuse of large-scale trials 93.68%. Thus the conclusion of theDevelopment of Soccer Training Tools (Service) in the Sepak TakrawGame can be declared as suitable for use as a tool in training.

Etiology and Recovery of Neuromuscular Function Following Academy Soccer Training.

Aim: To profile the etiology and recovery time-course of neuromuscular function in response to a mixed-content, standard training week in professional academy soccer players. We concurrently examined physical performance, cognitive function, and perceptual measures of mood and wellness states to identify a range of simple tests applied practitioners could use in the field as surrogate measures of neuromuscular function. Methods: Sixteen professional academy soccer players completed a range of neuromuscular, physical, perceptual, mood, and cognitive function tests at baseline and after a strenuous training day (pitch and gym), with retest at 24, 48, and 72 h, and further pitch and gym sessions after 48 h post-baseline. Maximal voluntary contraction force (MVC) and twitch responses to electrical stimulation (femoral nerve) during isometric knee-extensor contractions and at rest were measured to assess central nervous system (voluntary activation, VA) and muscle contractile (potentiated twitch force, Qtw,pot) function. Results: Strenuous training elicited decrements in MVC force post-session (−11%, p = 0.001) that remained unresolved at 72 h (−6%, p = 0.03). Voluntary activation (motor nerve stimulation) was reduced immediately post-training only (−4%, p = 0.03). No change in muscle contractile function (Qtw,pot) was observed post-training, though was reduced at 24 h (−13%, p = 0.01), and had not fully recovered 72 h after (−9%, p = 0.03). Perceptions of wellness were impaired post-training, and recovered by 24 h (sleepiness, energy) and 48 h (fatigue, muscle soreness, readiness to train). Countermovement jump performance declined at 24 h, while RSI (Reactive Strength Index) decrements persisted at 48 h. No changes were evident in adductor squeeze, mood, or cognitive function. Conclusion: Elite youth soccer training elicits substantial decrements in neuromuscular function, which are still present 72 h post-strenuous exercise. Though central processes contribute to post-exercise neuromuscular alterations, the magnitude and prolonged presence of impairments in contractile function indicates it is the restitution of muscular function (peripheral mechanisms) that explains recovery from strenuous training in academy soccer players.