Soccer-specific Test Research Articles

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.

Asymmetry in Ball Kicking Speed between Preferred and Non-preferred Leg in Young Soccer Players

Kicking ability is one of the most important skills in soccer. It is very important to have a good kicking ability with both feet. The main goal of this research was to determine a ball kicking asymmetry (KA) between preferred and non-preferred leg in young soccer players for the U-15 and the U-17 age category. The second goal was to determine differences in kicking asymmetry (KA) between players of different playing positions. 183 young players in U-15 category as well as 87 players from U-17 age category were tested with simple soccer specific test to evaluate kicking velocity (km/h) with preferred and non-preferred leg using Pocket radar. Testing took place on the artificial grass during dry and warm weather and ball was kicked while stationary at the 11-m spot. Results obtained with Student’s T-test showed that differences in the maximum kicking velocity with the preferred and non-preferred leg were statistically significant (p≤0.05) in both age groups (90.2±8.8 km/h /78.5±9.8 km/h for U-15) and (102.7±6.4 km/h /89.5±9.4 km/h for U-17) which confirmed KA is present. Additionally, univariate analysis of variance (ANOVA) showed that there were significant differences in KA between different playing positions in U-17 group (KA=14.57/9.72/14.1 for defenders, midfielders and attackers, respectively). Soccer kicking can be a quality indicator for assessing the soccer kicking ability. By assessing kicking ability, relevant results can be obtained in a fast, and efficient way and can be utilized in the selection process of young talents.

Effects of Game-Specific Demands on Accelerations during Change of Direction Movements: Analysis of Youth Female Soccer

The aim of this study was to assess center of mass (COM) acceleration and movement during change of direction (COD) maneuvers during a competitive soccer game to elucidate situation-specific demands of COD performance. This information can assist in developing soccer-specific tests and training methods. Fifteen elite-level female youth soccer players were tracked for one game with inertial measurement units (IMU) attached to the lower back. COD movements in combination with situational patterns were identified using high-speed video. LASSO regression was used to identify the most important predictors associated with higher vertical peak accelerations (PAv) of the COM during COD movements. COD angle, running speed, contact, and challenge from the opposition were identified as important features related to higher PAv. This study adds to the literature on the demands of COD performance in soccer match-play. The unique approach with game-specific situational data from female youth players provides increased insight into the game-demands of COD and agility performance. PAv in games was higher with larger COD angles, increased running speed, or with contact when the player was challenged by the opposition. A larger study including more games is warranted to increase confidence in using these variables as a basis for training or testing agility.

The Effect of a Single Dose of Citrulline on the Physical Performance of Soccer-Specific Exercise in Adult Elite Soccer Players (A Pilot Randomized Double-Blind Trial)

The purpose of this study was to evaluate the effect of a single intake of citrulline at 3 g and 6 g doses in adult elite soccer players performing sport-specific exercise. This randomized double-blind placebo-controlled study analyzed 18 soccer players from the top divisions of three European countries. Participants were randomized into three groups of six each and performed a field-based soccer-specific test for 18 min. Comparative analysis of heart rate, fatigue and post-exercise recovery was conducted. There were no statistically significant differences in most of the analyzed parameters, nor at any of the time points for lactate concentration. Players' RPE exercise test score did not reveal any differences. Neither a single intake of 3 g nor of 6 g of citrulline malate affected physical performance, subjective feelings of fatigue or post-exercise recovery in adult elite soccer players who performed a soccer-specific test.

Association Between Mental Imagery and Change of Direction Performance in Young Elite Soccer Players of Different Maturity Status.

Previous studies have not considered the potential influence of maturity status on the relationship between mental imagery and change of direction (CoD) speed in youth soccer. Accordingly, this cross-sectional study examined the association between mental imagery and CoD performance in young elite soccer players of different maturity status. Forty young male soccer players, aged 10-17 years, were assigned into two groups according to their predicted age at peak height velocity (PHV) (Pre-PHV; n = 20 and Post-PHV; n = 20). Participants were evaluated on soccer-specific tests of CoD with (CoDBall-15m) and without (CoD-15m) the ball. Participants completed the movement imagery questionnaire (MIQ) with the three- dimensional structure, internal visual imagery (IVI), external visual imagery (EVI), as well as kinesthetic imagery (KI). The Post-PHV players achieved significantly better results than Pre-PHV in EVI (ES = 1.58, large; p < 0.001), CoD-15m (ES = 2.09, very large; p < 0.001) and CoDBall-15m (ES = 1.60, large; p < 0.001). Correlations were significantly different between maturity groups, where, for the pre-PHV group, a negative very large correlation was observed between CoDBall-15m and KI (r = –0.73, p = 0.001). For the post-PHV group, large negative correlations were observed between CoD-15m and IVI (r = –0.55, p = 0.011), EVI (r = –062, p = 0.003), and KI (r = –0.52, p = 0.020). A large negative correlation of CoDBall-15m with EVI (r = –0.55, p = 0.012) and very large correlation with KI (r = –0.79, p = 0.001) were also observed. This study provides evidence of the theoretical and practical use for the CoD tasks stimulus with imagery. We recommend that sport psychology specialists, coaches, and athletes integrated imagery for CoD tasks in pre-pubertal soccer players to further improve CoD related performance.

Specific physical performances among male elite youth soccer players: effect of maturity status.

There is a lack of studies that investigated the relationship between anthropometric profile, biological maturity and specific soccer performances. Therefore, the aims of the present study were to establish normative data of anthropometric and specific physical performances and to determine the impact age and somatic maturation on young soccer players (U13-U19, n=487). Measurements include anthropometric variables to determine the age of peak height velocity (PHV), leg muscle volume (LMV) and soccer specific test (SST); Squat jump (SJ), Counter Movement jump (CMJ), sprint 10 meter (T<inf>10m</inf>), sprint 20 meter (T<inf>20m</inf>), sprint 30 meter (T<inf>30m</inf>) and intermittent-endurance tests. Reference values showed a significant difference between anthropometric variables, LMV and SST according to PHV categories. (M)ANOVA analysis showed a significant age using maturity interaction effect of all anthropometric variables. A significant result was reported in the majority of SST performances for the age, the T<inf>10m</inf> and for T<inf>20m</inf> performances. The full model of multiple regressions and the multiple equations was used to determine the best predictors of physical performances according to anthropometric variables. This study provides normative data for anthropometric characteristics and physical performances according to chronological age (U13-U19) and maturity groups of young soccer players.

Relationship Between Repeated Sprint Ability, Aerobic Capacity, Intermittent Endurance, and Heart Rate Recovery in Youth Soccer Players.

Rodríguez-Fernández, A, Sanchez-Sanchez, J, Ramirez-Campillo, R, Nakamura, FY, Rodríguez-Marroyo, JA, and Villa-Vicente, JG. Relationship between repeated sprint ability, aerobic capacity, intermittent endurance, and heart rate recovery in youth soccer players. J Strength Cond Res 33(12): 3406-3413, 2019-To investigate the relationship between repeated sprint ability (RSA) and several aerobic and anaerobic-related soccer-performance indicators, 45 youth soccer players (age 16.8 ± 0.1 years) were classified into "high" (HAF) or "low" aerobic fitness (LAF) (VO2max ≥ or <60 ml·kg·min, respectively) and completed an RSA test measuring best (RSAbest), mean (RSAmean), total sprint time (RSAtotal), and percent sprint decrement (Sdec). A laboratory VO2max test (LabTest) together with anaerobic threshold (VT) and peak speed was measured (vLabTest). In addition, a 20-m multistage shuttle run test (MSRT) and a soccer-specific test (TIVRE-Soccer test-TST) were completed. Heart rate (HR) and HR recovery (HRR) were measured during all tests. High aerobic fitness presented greater (p ≤ 0.05) performance in LabTest, MSRT and TST, at maximal effort, at VT, as well as faster HRR. RSA was similar between HAF and LAF. Contrary to HAF, LAF showed negative correlation between vLabTest with RSAmean (r = -0.6, p = 0.000) and Sdec (r = -0.4, p = 0.044). Also, LAF showed negative correlation between TST end speed (vTST) and RSAmean (r = -0.5, p = 0.005) and Sdec (r = -0.5, p = 0.003). In LAF, RSA was strongly correlated with locomotor factors (e.g., vTST; VT) in both laboratory and field tests. Athletes with high total HRR (>12.5%) in TST presented better (p ≤ 0.05) Sdec in the RSA test. The multiple regression revealed that the LAF vLabTest explained 44.9, 40.0, and 13.5% of the variance in RSAbest, RSAmean, and Sdec, respectively. Practitioners may consider these findings to optimize youth athletes' assessment and preparation processes.

Effects of Caffeinated Gum on a Battery of Soccer-Specific Tests in Trained University-Standard Male Soccer Players.

The purpose of this study was to determine whether caffeinated gum influenced performance in a battery of soccer-specific tests used in the assessment of performance in soccer players. In a double-blind, randomized, crossover design, 10 male university-standard soccer players (age: 19 ± 1 years, stature: 1.80 ± 0.10m, body mass: 75.5 ± 4.8kg) masticated a caffeinated (200mg; caffeine) or control (0mg; placebo) gum on two separate occasions. After a standardized warm-up, gum was chewed for 5min and subsequently expectorated 5min before players performed a maximal countermovement jump, a 20-m sprint test, and the Yo-Yo Intermittent Recovery Test Level 1. Performance on 20-m sprints was not different between trials (caffeine: 3.2 ± 0.3s, placebo: 3.1 ± 0.3s; p = .567; small effect size: d = 0.33), but caffeine did allow players to cover 2.0% more distance during Yo-Yo Intermittent Recovery Test Level 1 (caffeine: 1,754 ± 156m, placebo: 1,719 ± 139m; p = .016; small effect size: d = 0.24) and increase maximal countermovement jump height by 2.2% (caffeine: 47.1 ± 3.4cm, placebo: 46.1 ± 3.2cm; p = .008; small effect size: d = 0.30). Performance on selected physical tests (Yo-Yo Intermittent Recovery Test Level 1 and countermovement jump) was improved by the chewing of caffeinated gum in the immediate period before testing in university-standard soccer players, but the sizes of such effects were small. Such findings may have implications for the recommendations made to soccer players about to engage with subsequent exercise performance.

Evidence of balance training-induced improvement in soccer-specific skills in U11 soccer players.

The present study aimed to determine the role of balance training improving technical soccer skills in young players. Two U11 soccer teams were randomly assigned one to either balance training (BT; n=22) or control group (Ctrl; n=21). At the end of their habitual soccer training (identical in BT and Ctrl), BT underwent additional balance training for 12weeks (3sessions/week, 20minutes per session), while Ctrl had a 20-minute scrimmage. Before and after the intervention, BT and Ctrl underwent two soccer-specific tests (Loughborough Soccer Passing, LSPT, and Shooting, LSST, Tests), and bipedal and unipedal balance evaluations. After intervention, both groups decreased the trials time and improved passing accuracy, with larger improvements in BT than Ctrl (LSPT penalty time [CI95% ]: -2.20seconds [-2.72/-1.68]; ES [CI95% ]: -2.54seconds [-3.34/-1.74]). Both groups improved balance ability, with BT showing larger increments in bipedal tests than Ctrl (static balance: -29mm [-42/-16]; ES: -1.39 [-2.05/-0.72]; limit of stability: 4% [3/5]; ES 3.93 [2.90/4.95]; unipedal quasi-dynamic balance: 0.07a.u. [0.03/0.11]; ES: 1.04 [0.40/1.67] and active range of motion: -5% [-8/-2]; ES -0.89 [-1.51/-0.26]). Low-to-moderate correlations between the players' technical level and unipedal balance ability were retrieved, particularly in the non-dominant limb (R from 0.30 to 0.48). Balance training improved some technical soccer skills more than habitual soccer training alone, suggesting that young soccer players may benefit from additional balance training added to their traditional training.

Importance of Reactive Agility and Change of Direction Speed in Differentiating Performance Levels in Junior Soccer Players: Reliability and Validity of Newly Developed Soccer-Specific Tests.

Agility is a significant determinant of success in soccer; however, studies have rarely presented and evaluated soccer-specific tests of reactive agility (S_RAG) and non-reactive agility (change of direction speed – S_CODS) or their applicability in this sport. The aim of this study was to define the reliability and validity of newly developed tests of the S_RAG and S_CODS to discriminate between the performance levels of junior soccer players. The study consisted of 20 players who were involved at the highest national competitive rank (all males; age: 17.0 ± 0.9 years), divided into three playing positions (defenders, midfielders, and forwards) and two performance levels (U17 and U19). Variables included body mass (BM), body height, body fat percentage, 20-m sprint, squat jump, countermovement jump, reactive-strength-index, unilateral jump, 1RM-back-squat, S_CODS, and three protocols of S_RAG. The reliabilities of the S_RAG and S_CODS were appropriate to high (ICC: 0.70 to 0.92), with the strongest reliability evidenced for the S_CODS. The S_CODS and S_RAG shared 25–40% of the common variance. Playing positions significantly differed in BM (large effect-size differences [ES]; midfielders were lightest) and 1RM-back-squat (large ES; lowest results in midfielders). The performance levels significantly differed in age and experience in soccer; U19 achieved better results in the S_CODS (t-test: 3.61, p < 0.05, large ES) and two S_RAG protocols (t-test: 2.14 and 2.41, p < 0.05, moderate ES). Newly developed tests of soccer-specific agility are applicable to differentiate U17 and U19 players. Coaches who work with young soccer athletes should be informed that the development of soccer-specific CODS and RAG in this age is mostly dependent on training of the specific motor proficiency.

The effects of Cold Water Immersion on the performance of soccer specific fitness test

The effects of Cold Water Immersion on the performance of soccer specific fitness test

Physiological Characteristics of Incoming Freshmen Field Players in a Men's Division I Collegiate Soccer Team.

Freshmen college soccer players will have lower training ages than their experienced teammates (sophomores, juniors, seniors). How this is reflected in field test performance is not known. Freshmen (n = 7) and experienced (n = 10) male field soccer players from the same Division I school completed soccer-specific tests to identify potential differences in incoming freshmen. Testing included: vertical jump (VJ), standing broad jump, and triple hop (TH); 30-m sprint, (0–5, 5–10, 0–10, and 0–30 m intervals); 505 change-of-direction test; Yo-Yo Intermittent Recovery Test Level 2 (YYIRT2); and 6 × 30-m sprints to measure repeated-sprint ability. A MANOVA with Bonferroni post hoc was conducted on the performance test data, and effect sizes and z-scores were calculated from the results for magnitude-based inference. There were no significant between-group differences in the performance tests. There were moderate effects for the differences in VJ height, left-leg TH, 0–5, 0–10 and 0–30 m sprint intervals, and YYIRT2 (d = 0.63–1.18), with experienced players being superior. According to z-score data, freshmen had meaningful differences below the squad mean in the 30-m sprint, YYIRT2, and jump tests. Freshmen soccer players may need to develop linear speed, high-intensity running, and jump performance upon entering a collegiate program.

The Hoff circuit test is more specific than an incremental treadmill test to assess endurance with the ball in youth soccer players.

The assessment of aerobic endurance is important for training prescription in soccer, and is usually measured by straight running without the ball on a track or treadmill. Due to the ball control and technical demands during a specific soccer test, the running speeds are likely to be lower compared to a continuous incremental test. The aim of the present study was to compare the heart rate (HR), rating of perceived exertion (RPE) and speeds corresponding to 2.0 mmol∙L-1, 3.5 mmol∙L-1, lactate threshold (Dmax method) and peak lactate determined in the laboratory and in the Hoff circuit soccer-specific test. Sixteen soccer players (16±1 years) underwent two incremental tests (laboratory and Hoff circuit tests). The speeds were significantly higher in the treadmill test than on the Hoff circuit (2.0 mmol∙L-1: 9.5±1.2 and 8.1±1.0 km∙h-1; 3.5 mmol∙L-1: 12.0±1.2 and 10.2±1.1 km∙h-1; Dmax: 11.4±1.4 and 9.3±0.4 km∙h-1; peak lactate: 14.9±1.6 and 10.9±0.8 km∙h-1). The HR corresponding to 3.5 mmol∙L-1 was significantly higher on the Hoff circuit compared to the laboratory test (187.5±18.0 and 178.2±17.6 bpm, respectively; P <0.001), while the RPE at the last incremental stage was lower on the Hoff circuit (P < 0.01). The speeds during the Hoff specific soccer test and the HR corresponding to 2.0 mmol∙L-1, 3.5 mmol∙L-1 and Dmax/threshold were different compared with the laboratory test. The present study shows that it is possible to assess submaximal endurance related variables specifically in soccer players.

Physical characteristics that predict involvement with the ball in recreational youth soccer

ABSTRACTThis study examined the relative contribution of age, stage of puberty, anthropometric characteristics, health-related fitness, soccer-specific tests and match-related technical performance to variance in involvements with the ball during recreational 5-a-side small-sided (32 × 15 m) soccer matches. Using a cross-sectional design, 80 healthy male students (14.6 ± 0.5 years of age; range 13.6–15.4) who played soccer recreationally were randomly divided into 10 teams and played against each other. Measurements included height, body mass, pubertal status, health-related fitness (12-min walk/run test, standing long jump, 15-m sprint and sit-ups in 30 s), soccer-specific tests (kicking for speed, passing for accuracy and agility run with and without a ball), match-related technical performance (kicks, passes and dribbles) and involvements with the ball during matches. Forward multiple regression analysis revealed that cardiorespiratory fitness (12-min walk/run test) accounted for 36% of the variance in involvements with the ball. When agility with the ball (zigzag running) and power (standing long jump) were included among the predictors, the total explained variance increased to 62%. In conclusion, recreational adolescent players, regardless of their soccer-specific skills, may increase participation in soccer matches most through physical activities that promote improvement in cardiorespiratory fitness, muscle power and agility.

Comparison of Beep Test and Hoff Test for VO2max Estimation Among Soccer Players

PURPOSE: Examining cardiorespiratory fitness levels (CRF) among athletes are important to coaches and can be measured through a variety of field tests. CRF assessed directly through a maximal graded treadmill test in a laboratory setting is not realistic for most coaches to measure maximal oxygen consumption (VO2max). Thus a variety of field tests exist to estimate VO2max. The current study was designed to examine the validity of VO2max estimates from the Beep and Hoff test. METHODS: The Beep Test and soccer specific test, Hoff test, were conducted on male Division III soccer athletes. The Beep Test involves running a 20-m distance at a certain pace; pace progressively increased through stages and simulates a graded treadmill test. Two published equations and an iPhone application were used to estimate VO2max from the Beep Test. The Hoff test consists of running and changing directions while dribbling a soccer ball for 8 minutes; total distance covered was used to estimate VO2max. RESULTS: Comparing two published equations to estimate VO2max from the Beep Test was significant (51.06+4.81 vs 53.16+3.30 ml.kg-1.min-1, p<.05). When comparing estimated VO2max from the published equations and from the app (52.13+4.57 ml.kg-1.min-1), significant correlation coefficients were found (r=.906 and r=.913, p.05). Estimated VO2max values using the app and Hoff test provided fair results, r=.661, p<.05. CONCLUSIONS: Estimating VO2max using the Beep Test is a valid field test for coaches to gauge CRF levels. For coaches, using an app to predict VO2max is a feasible option; for a more accurate estimation published equations should be used to estimate CRF levels among athletes. Incorporating a sport specific test to estimate VO2max may require more practice and familiarity with the test itself to accurately estimate fitness levels.

The Influence of Anaerobic and Aerobic Fitness on the Technical Skill Ability of National Elite Male Under-18 African Soccer Players

Aim. Elite level soccer players cover about 10 km during a 90-minute game. Although running is the predominant activity in soccer, explosive movements such as sprinting, jumping and kicking are important for successful performance. The aims of this study were to determine the technical skill ability, aerobic- and anaerobic fitness of elite male under-18 African soccer players; and to determine whether a relationship exists between the technical skill ability and aerobic and anaerobic fitness. Methods. One-hundred-and-sixty-nine (n=169) elite male under-18 soccer players from eleven African countries participated in the study. Technical skill ability (dribbling, crossing, shooting, passing) was assessed using four soccer-specific tests. Aerobic and anaerobic fitness was measured through a 20-metre multi-stage shuttle run test and a repeated sprint ability test respectively. Results. The results showed that VO2max level (47.71 ml·kg-1·min-1) was much lower than indicated in literature (60 ml·kg- 1·min-1). An average total distance of 704.36 m was recorded for the repeated sprint ability test. A positive correlation was found between dribbling and both aerobic and anaerobic fitness. Results indicated differences among various playing positions with forwards producing best performance in the passing and shooting skills test, forwards and defenders possessing the highest level of aerobic fitness and goalkeepers displaying the lowest level of aerobic and anaerobic fitness. Conclusion. Aerobic and anaerobic fitness influenced the players’ ability to dribble. The African soccer players generally have a lower level of both aerobic and anaerobic fitness. DOI: 10.5901/mjss.2014.v5n27p1704

Reliability and validity of the soccer specific INTER field test

The aims of this study were to explain how the Intermittent Endurance Running (INTER) test is executed, describe physiological responses during testing, and evaluate reliability and content validity in this new soccer specific test. The test consists of 20 m shuttle running, interspersed with straight sprints, agility sprints, walking and resting. Shuttle run speed is increased at each level until exhaustion. Thirteen male professional players participated in the present study. Exercise tolerance time, distance covered, mean blood lactate and mean heart rate were 25:51 ± 2:41 min, 2892 ± 324 m, 5.5 ± 1.2 mmol · L−1 and 161 ± 11 beats · min−1, respectively, during the INTER test. Sprint and agility performance decreased significantly at higher levels. Eight of the players performed a retest for reliability evaluations. Mean difference ± 95% limits of agreement, coefficient of variation (CV) and intraclass correlation coefficient (ICC) for exercise tolerance time between test and retest were -00:41 ± 02:25 min, 2.5% and 0.75, respectively. The CV for sprint and agility performance between test and retest was <1%. The INTER test mimics soccer games on distance/time ratio, frequency of sprints, heart rate and blood lactate values, and could be an alternative field test for evaluating essential physical performance aspects in soccer players.

Relationship between Functional Capacities and Performance Parameters in Soccer

Aim of this study was to determine the relationship between functional capacities and skills performance among young soccer player. The research was conducted on a sample of 22 players aged U-14, members of the elite junior soccer club. Players were tested for aerobic capacities (Soccer specific endurance tests, Beep test), anaerobic capacities (Sprint test, Repeated sprint test, 300 meter run test) and skill performace in phase of attack and defense. Anaerobic capacity of players explain 37% of the variance (p = 0.03) for defensive tactical elements, while the set of functional aerobic variables (Hoff test, p = 0.18; beep test, p = 0.93) has explained 37% (p = 0.03) of defensive players ability. Set of predictors of functional anaerobic variables (Sprint test, Repeated Sprint Ability, 300 meter run test) explain 32% (p = 0.04) criteria, while the set of predictors of functional aerobic variables (Hoff test, 20m multi-stage shuttle run test) explain 26% (p = 0.03) criteria. On the basis of the research we can conclude that there is a strong correlation between the players’ performance and tactical skill, whether it is a tactical-technical element of the phase of attack or defense. Therefore, coaches need to develop both components to achieve desired results in the competition games.

Is there a relationship between the playing position of soccer players and their food and macronutrient intake?

Many authors have proposed the necessity of the design and implementation of dietary and nutrition education programs for soccer players, although little information is available about the determinants of food selection and nutrient intake. The aim of this study was to evaluate the nutritional intake and eating patterns of soccer players according to their playing position in the team. Eighty-seven young male soccer players (aged 16-21 years) were recruited from the junior teams of a Spanish First Division Soccer League Club and divided into 6 positional categories (goalkeepers, full-backs, centre-backs, midfielders, wingers, and forwards). Body composition (height, weight, and body fat), performance in soccer-specific tests (jumping, sprinting, and intermittent endurance), and dietary intake (weighed food intake method) were assessed. A spontaneous higher carbohydrate intake was observed for full-backs, midfielders, and wingers (g·kg(-1) body mass: 4.9 ± 1.0, 4.9 ± 1.3, 4.9 ± 0.8; % of energy intake: 47 ± 5, 46 ± 6, 46 ± 4), compared with goalkeepers and centre-backs (g·kg(-1) of body mass: 3.9 ± 1.0, 4.3 ± 1.1; % of energy intake: 44 ± 3, 42 ± 4). These differences were related to food selection patterns, and a higher contribution to daily energy intake of cereals, derivatives, and potatoes was observed between full-backs compared with goalkeepers and centre-backs (33% vs. 27% and 25%). The magnitude of these differences is limited considering the whole diet, and an inadequate nutrient intake were observed in most individuals of every group. The design and implementation of nutrition intervention programs, taking into consideration positional differences in nutritional intake, would be useful for these players.

Effects of carbohydrate and caffeine co-ingestion on a reliable simulated soccer-specific protocol

The aim of this study was to evaluate the effect of co-ingesting carbohydrate and caffeine (CHO+CAF) in comparison to carbohydrate (CHO) and placebo (PLA), during a reliable soccer-specific test (Currell...