Greater Psychophysiological Intensities in Conditioned Games May Impair Technical Performance: An Exploratory Study in Youth Male Soccer Players.

PURPOSE: The aim of this study was 2-fold: (1) to examine the relationships between psychophysiological responses and locomotor demands with variations in technical performance during 2v2 and 4v4 conditioned games and (2) to compare psychophysiological and locomotor responses among players exhibiting higher and lower technical performance levels during the conditioned games. METHODS: Twenty-four male youth soccer players (16.3 ± 0.8 y old) participating at the trained/developmental level underwent monitoring for psychophysiological responses (including heart rate, rating of perceived exertion, and visual analog scale), locomotor demands (such as distance covered), and technical performance variables (including successful and unsuccessful passes and shots, as well as lost balls) across 2v2 and 4v4 formats. These formats were applied 4 times within a single session and were replicated twice over 2 weeks. RESULTS: Large correlations between the number of lost balls per minute and mean heart rate were found in both the 2v2 and 4v4 games (r = .586 and r = .665, respectively). Successful shots were inversely and largely correlated with mean heart rate (r = -.518) in 4v4 games. The number of interceptions per minute was inversely and significantly correlated with the visual analog scale in 2v2 and 4v4 games (r = -.455 and r = -.710, respectively). The frequency of lost balls was significantly higher among players who attained a higher mean heart rate (2v2: +42.9%, P = .031, d = -0.965; 4v4: +57.1%, P < .001, d = -2.072). CONCLUSIONS: Coaches should be aware that highly psychophysiologically demanding scenarios may significantly impair technical performance. Therefore, prioritizing technical performance by deliberately adjusting the intensity should be considered.

Correlations of Aerobic Capacity with External and Internal Load of Young Football Players during Small-Sided Games.

Aerobic capacity plays a crucial role in football performance, making it a focal point in training processes. Small-sided games (SSGs) are widely used in football training, but the relationship between aerobic capacity and running performance during SSGs remains unclear. The aim of this study was to investigate possible correlations between maximum oxygen uptake (VO2max) and running performance in youth football players in SSGs (4:4, 3:3, 2:2, 1:1) with three different pitch sizes per player (150, 100, 75 m2/player). Sixteen male U15 football players participated in the study. Players underwent the Yo-Yo intermittent recovery test level 1, and their VO2max was estimated based on their performance. Subsequently, players participated in SSGs wearing GPS devices to measure internal and external load. Pearson or Spearman correlation was applied for statistical analysis depending on the normal distribution of the data. The results reveal that, for 4:4 and 3:3 relationships, larger pitches led to a greater impact of aerobic capacity (total distance (TD): 4:4, 150 m2/pl, r = 0.715, p = 0.002; 100 m2/pl, r = 0.656, p = 0.006; 75 m2/pl, r = 0.586, p = 0.017). In the 2:2 relationship, the opposite was observed, with more correlations appearing on smaller pitches (TD: 2:2, 100 m2/pl, r = 0.581, p = 0.018; 75 m2/pl, r = 0.747, p < 0.001). In the 1:1 relationship, correlations with VO2max, total distance, and speed were observed only on the larger pitch. In conclusion, the aerobic capacity of young football players can influence running performance indicators in SSGs. Therefore, aerobic capacity could serve as a criterion for team composition, making SSGs more competitive. Additionally, the variation in correlations in the 2:2 relationship and their limited presence in the 1:1 relationship may be attributed to technical-tactical factors, such as increased ball contacts and one-on-one situations typically occurring in smaller setups.

Understanding the role of gaze behaviour and coaching experience in the assessment of youth soccer teams.

This study aimed to explore the perceptual-cognitive characteristics of coaches as they assessed team performance in youth soccer. The primary focus was to investigate the alignment between coaches' subjective analyses of team behaviour and objective analyses, while also examining the relationship between coaches' gaze behaviour and their levels of coaching experience, particularly considering the potential differences that may exist among coaches with varying levels of experience. Sixty-five male and female adults with various soccer coaching experience (experienced, novice, other team sport experience, and non-team sport experience) watched five 4-minute videos and assessed team behaviour. These subjective evaluations were compared to objective data obtained from video analysis and GPS, which included measures of completed skills, spatiotemporal characteristics, and passing networks. The participants' fixation duration and frequency were measured for each video clip, and the area around the ball specifically. The study found no significant differences between groups regarding the number of times participants' subjective analysis aligned with the objective data (p = 0.059, ɳ2 = 0.07). However, coaches with soccer coaching experience demonstrated a higher fixation frequency and more revisits to the ball area when compared to participants without soccer experience (p = <.001, ɳ2 = 0.09). The current study offers a unique approach to uncovering soccer coaching expertise by combining objective and subjective evaluations of team performance. In summary, the study reveals that coaching experience did not impact how often coaches subjective analyses matched objective data. However, soccer coaches had distinctive gaze behaviour patterns where they revisited the area around the ball more often.

Coaches' perceptions of collective behaviour in soccer teams do not align with objective data, regardless of their level of coaching experience.Gaze behaviour differs between coaches with varying expertise levels.Both experienced and novice coaches visually revisit the area around the ball more often than non-coaches when assessing team performance.Quantitative data may provide an additional level of team analysis than subjective coach assessment alone.

Effects of a 16-week recreational small-sided games soccer intervention on body composition and physical fitness in sedentary young adults: A randomized controlled study.

Recreational small-sided games (SSGs) have demonstrated positive effects on body composition and physical fitness, while minimizing adverse outcomes. In this randomized controlled study, we aimed to investigate the impact of incorporating an additional 16-week intervention program involving recreational soccer SSGs on parameters related to body composition and physical fitness in sedentary young adult males and females. Sixty sedentary participants, with a mean age of 20.2 years, were randomly assigned to either the small-sided games group (SSG; n = 30) or the active control group, which participated in regular physical education classes (CG; n = 30). The SSG group engaged in the same activities as the control group but additionally participated in a recreational SSG football program. This program involved continuous and intermittent moderate-to high-intensity exercises conducted on 20 m × 30 m and 30 m × 50 m football fields. In contrast, the CG group received 1 h of physical education once a week. The interventions were administered for a duration of sixteen weeks. Baseline, 8-week, and post-intervention assessments were conducted to measure body mass (BM), body mass index (BMI), waist circumference (WC), hip circumference (HC), waist-to-hip ratio (WHR), skinfold thickness (SFT), standing broad jump (SBJ), vertical jump (VJ), handgrip strength (HG) for both left and right hands, shuttle run distance (SRD), and shuttle run estimated VO2max. Results indicated that both male and female participants in the SSG group exhibited significant improvements in BM, BMI, SFT, WC, HC, and WHR following the intervention (p < 0.05), whereas the control group demonstrated no significant changes over the study period (p > 0.05). Additionally, SSG participants (regardless of sex) displayed significant enhancements in SBJ, VJ, HG, SRD, and VO2max (p < 0.05), while the control group did not exhibit any significant alterations (p > 0.05). The findings from this experimental study suggested that a 16-week recreational soccer SSG intervention effectively enhanced body composition and physical fitness among overweight sedentary young adults, offering a pleasurable alternative to conventional training approaches.

Exploring Coaches' Cognitive Perception of Football Training Tasks: A Questionnaire-Based Study and Comparison with a Framework Tool for Assessing Cognitive Demands in Small-Sided Games / Exploración de la percepción cognitiva de los entrenadores sobre las tareas de entrenamiento de fútbol: un estudio basado en cuestionarios y una comparación con una herramienta marco para evaluar las demandas cognitivas en juegos reducidos / Exploração da perceção cognitiva de tarefas de treino em futebol: Estudo baseado numquestionário e comparação com uma ferramenta para avaliar e comparar as exigências cognitivas em jogos reduzidos

La función cognitiva es crucial en entornos de rendimiento competitivo debido al tipo de tareas y carga de trabajo involucradas. Sin embargo, aún se necesita determinar cómo toda la información ambiental en un entorno competitivo afecta la carga cognitiva.Por lo tanto, el objetivo fue investigar la percepción cognitiva de los entrenadores sobre las tareas de entrenamiento de fútbol, mediante el uso de un cuestionario y comparar los resultados con una herramienta de marco para evaluar las demandascognitivas en juegos reducidos. Un total de 57 entrenadores de fútbol (a nivel nacional y regional) completaron un cuestionario para calificar las demandas cognitivas percibidas de doce situaciones diferentes de juegos en espacios reducidos. Las respuestas fueron hechas por cada entrenador a partir de un conjunto de alternativas proporcionadas por los autores utilizando una escala de uso de Likert de 10 puntos. La carga cognitiva durante los juegos reducidos se calculó mediante una ecuación que incluía el número de jugadores implicados en la tarea, la superficie ocupada por cada jugador y la duración del ejercicio. Los resultados del cuestionario mostraron que los entrenadores de nivel nacional presentaron resultados de correlación más altos, mostrando una alta concordancia entre la percepción de los entrenadores y los resultados de la carga cognitiva en comparación con los entrenadores de nivel regional. La relación establecida entre todas las variables mostró que la complejidad de las tareas aumenta utilizando formatos con mayor número de jugadores, áreas pequeñas y ejercicios de mayor duración. Por lo tanto, el marco de carga cognitiva puede ser una herramienta útil y sencilla para quelos entrenadores evalúen las demandas cognitivas durante las sesiones de entrenamiento.(AU)

Cognitive function is crucial in competitive performance environments due to the type of tasks and workload involved. Thus, the present study aimed to investigate coaches’ cognitive perception of football training tasks, through the use of a questionnaire and compare the results with a framework tool to assess cognitive demands in small-sided games. A total of 57 football coaches (national and regional levels) filled out a questionnaire to rate the perceived cognitive demands of twelve different small-sidedgame situations. The answers were made by each coach from a set of alternatives supplied by the authors using a 10-point Likert use scale. The cognitive load during small-sided games was calculated using an equation that included the number of players involved in the task, the surface area occupied by eachplayer, and the duration of the exercise. The questionnaire results have shown that national-level coaches presented higher correlation results showing a high agreement between coaches' perception and the cognitive load results when compared to regional-level coaches. The relationship established between all variables showed that the complexity of tasks increases using formats with a larger number of players, small areas, and bigger duration drills. Thus, the cognitive load framework may be a useful and simple tool to coaches assess the cognitive demands during training sessions.(AU)

A função cognitiva é crucial em ambientes de desempenho competitivo devido ao tipo de tarefas e carga de trabalho envolvidas. No entanto, ainda precisa ser determinado como todas as informações ambientais em em contexto competitivo afetam a carga cognitiva. Assim, o objetivo deste estudofoi investigar a perceção cognitiva de treinadores sobre tarefas de treino de futebol, através de um questionário e comparando os resultados com um instrumento para avaliar as exigências cognitivas durante jogos reduzidos.Um total de 57 treinadores de futebol (nível nacional e regional) preencheram um questionário para avaliar as exigências cognitivas de doze situações diferentes jogos-reduzido. As respostas foram dadas por cada treinador a partir de um conjunto de alternativas fornecidas pelos autores utilizando uma escala de Likert de 10 pontos. A carga cognitiva durante pequenos jogos foi calculada através de uma equação queincluía o número de jogadores envolvidos na tarefa, a área de superfície ocupada por cada jogadore a duração do exercício. Os resultados do questionário mostraram que os treinadores de nível nacional apresentaram resultados de correlação mais elevados, mostrando uma alta concordância entre a perceção dos treinadores e os resultados de carga cognitiva em comparação com os treinadores de nível regional. A relação estabelecida entre todas as variáveis mostrou que a complexidade das tarefas aumenta utilizandoformatos com maior número de jogadores, áreas pequenas e exercícios de maior duração. Portanto, esta ferramenta para avaliar a carga cognitiva pode ser uma forma útil e simples para os treinadores avaliarem as exigências cognitivas durante as sessões de treino.(AU)

Physiological and locomotor variations of 3v3 and 5v5 small-sided games soccer formats: A 4-month study on sedentary young adults.

The objectives of this study were twofold: (a) to analyze the variability of 3v3 and 5v5 small-sided games (SSG) formats in sedentary young adults, and (b) to compare the physiological and locomotor demands of 3v3 and 5v5 SSG formats while considering variations based on sex. The study followed a longitudinal design over 4 months. Thirty sedentary young adults with a mean age of 20.2 ± 1.0 years, height of 1.67 ± 0.06 m, and body mass of 86.3 ± 11.8 kg were included in the study. The participants engaged in 3v3 and 5v5 SSG formats, with each format being played 10 times per month. During each session, heart rate (HR), rate of perceived exertion (RPE), and total distance were measured and analyzed. The within-player variability for HR ranged from a minimum of 1.6% to a maximum of 2.8% (considering the levels at each month), while the between-players variability for HR ranged from a minimum of 1.4% to a maximum of 2.6% (considering the levels at each month). Similar variability patterns were observed for the other outcomes. In terms of comparisons between the formats, the 3v3 format resulted in higher RPE than the 5v5 format for both male (p = 0.006) and female (p = 0.628) participants, as well as for the other outcome measures. In summary, these findings highlight the reproducibility of physiological responses in 3v3 and 5v5 SSG among sedentary individuals. Notably, the 3v3 format consistently induced higher RPE levels. These findings underscore the importance of programming SSG based on sex and format preferences for optimizing exercise outcomes in sedentary.

Health and performance effects of 12 weeks of small-sided street football training compared to grass football training in habitually active young men.

PURPOSE: The purpose of the present study was to investigate the health and exercise performance effects of street football training on very small pitches surrounded by boards in young habitually active men in comparison to small-sided football training on grass. METHODS: Thirty-nine habitually active men (30.7 ± 6.7 years, 90.9 ± 16.6 kg, 183.8 ± 4.5 cm, 39.6 ± 6.0 mL/min/kg) were randomly assigned to a street football training group (ST) or grass football group (GR) playing small-sided games for 70 min, 1.5 and 1.7 times per week for 12 weeks, respectively, or an inactive control group (CO). Intensity during training was measured using heart rate (HR) and GPS units. Pre- and post-intervention, a test battery was completed. RESULTS: Mean HR (87.1 ± 5.0 vs. 84.0 ± 5.3%HRmax; P > 0.05) and percentage of training time above 90%HRmax (44 ± 28 vs. 34 ± 24%; P > 0.05) were not different between ST and GR. VO2max increased (P < 0.001) by 3.6[95% CI 1.8;5.4]mL/min/kg in GR with no significant change in ST or CO. HR during running at 8 km/h decreased (P < 0.001) by 14[10;17]bpm in ST and by 12[6;19]bpm in GR, with no change in CO. No changes were observed in blood pressure, resting HR, total body mass, lean body mass, whole-body bone mineral density, fasting blood glucose, HbA1c, plasma insulin, total cholesterol(C), LDL-C or HDL-C. Moreover, no changes were observed in Yo-Yo IE2 performance, 30-m sprint time, jump length or postural balance. CONCLUSION: Small-sided street football training for 12 weeks with 1-2 weekly sessions led to improvements in submaximal exercise capacity only, whereas recreational grass football training confirmed previous positive effects on submaximal exercise capacity as well as cardiorespiratory fitness.

Speed Effects on the Accuracy of Heart Rate as Oxygen-Uptake Indicator in Short-Distance Shuttle Running.

Purpose: Despite the accuracy of heart rate (HR) as an indicator of the aerobic engagement has been evaluated in several intermittent on-court activities, its validity as an oxygen uptake (V˙O2) indicator during shuttle running over short paths remains uncertain. Moreover, it is unclear whether speed may affect such validity. This study evaluated the HR ability in estimating the V˙O2 during 5-m shuttle running at different speeds. Methods: V˙O2 and HR of 12 physically active young men were recorded during an incremental forward running (FW) protocol and a 5-m shuttle test at 50%, 60%, and 75% of maximal aerobic speed (MAS). Slope and intercept of the relationship between HR and V˙O2 (HR/V˙O2) were individually determined, in both protocols. The HR measured during the shuttle test was used in the FW HR/V˙O2 to estimate V˙O2 at each shuttle speed. A paired Student's t-test compared slopes and intercepts of the two HR/V˙O2. A two-way RM-ANOVA and an equality test examined, respectively, the differences and the equality between measured and estimated V˙O2. Lastly, a Bland-Altman plot described the accuracy and precision of the estimated V˙O2 at each shuttle intensity. Results: Slopes and intercepts of the HR/V˙O2 appeared not different between FW and shuttle running. At 50%MAS, HR underestimated the V˙O2 (~7%), whereas returned accurate values at the two higher velocities, although with high variability (±18%). Conclusions: When using HR as V˙O2 indicator during shuttle running over short paths, a separated analysis of the HR validity as V˙O2 indicator is recommended especially when administering different exercise intensities.

Examining the effect of task constraints on the emergence of creative action in young elite football players by using a method combining expert judgement and frequency count.

In adult football, small-sided games are associated with increased action variability and suggested to promote more creative actions compared to regular 11v11 formats. This aligns with predictions from an ecological approach to perception and action that creative actions emerge in environments that grant variability in action, instead of being an expression of the individual player's ability to generate ideas. To further evidence for this prediction, the current study aimed to expand this observation to elite youth football players. To this end, the number of different and creative actions in 4v4 small-sided game and a 11v11 regular-sided game among 10- to 12-year-old elite football players were examined. We analyzed a total of 7922 actions, which were categorized for type and creativity. Based on a subset of these actions, a panel of elite football coaches judged action types occurring below 0.5% as significantly more creative than more frequent action types. Hence, we used an occurrence of 0.5% as threshold to distinguish creative actions from non-creative actions. The results showed that the total number of actions, the number of different action types, the number creative actions and the number of different creative action types was significantly higher for the small-sided game format than the regular-sided game. In conclusion, this study confirms that in elite youth football, small-sided games induce a more variable and creative action repertoire. This shows that practitioners can design learning environments that promote the emergence of creative actions.

The effects of high-intensity interval training at the anaerobic and psychomotor fatigue thresholds on physiological parameters in young soccer players: a prospective study.

This study aimed to investigate the effects of a 4-week specific high-intensity interval training (HIIT) program performed between the anaerobic threshold (ANT) and the psychomotor fatigue threshold (PFT) on physiological parameters in 14 professional soccer players at the under-17 level. The first and second stages of the research protocol included a treadmill running exercise with increasing load and six 3-min four-versus-four games of soccer with a 3-min break between games. Players then participated in a training microcycle involving three specific HIIT exercises twice per week for 4 weeks, after which they repeated stages one and two, followed by an assessment of changes. The measurement of lactate (LA) determined ANT, whereas the choice reaction time (CRT) indicated PFT among other selected physiological parameters. The repeated-measure analysis of variance (ANOVA) compared mean values for the examined variables using Bonferroni post hoc test. It demonstrated significantly increased maximal oxygen consumption (VO2 max) from 45.9 ± 3.0 to 48.7 ± 2.6 at the ANT and from 49.1 ± 3.4 to 52.0 ± 3.6 on the PFT after 4 weeks of training. A significant increase in the running speed (RS) at both thresholds and heart rate (HR) at the ANT (p ≤ 0.05) was also recorded. Moreover, the players exceeded their intensity of effort during ANT while playing four-versus-four soccer matches, but they did not reach intensity during PFT. In conclusion, the findings of the study demonstrated that both thresholds shifted toward higher loads and the proposed specific HIIT effectively increased the exercise capacity of soccer players.

An ecological investigation of average and peak external load intensities of basketball skills and game-based training drills.

This study quantified average and peak external intensities of various basketball training drills. Thirteen youth male basketball players (age: 15.2 ± 0.3 years) were monitored (BioHarness-3 devices) to obtain average and peak external load per minute (EL · min-1; peak EL · min-1) during team-based training sessions. Researchers coded the training sessions by analysing the drill type (skills, 1vs1, 2vs2, 3vs0, 3vs3, 4vs0, 4vs4, 5vs5, 5vs5-scrimmage), court area per player, player's involvement in the drill (in percentage), playing positions (backcourt; frontcourt) and competition rotation status (starter; rotation; bench). Separate linear mixed models were run to assess the influence of training and individual constraints on average and peak EL · min-1. Drill type influenced average and peak EL · min-1 (p < 0.05), but with different directions of effects. EL · min-1 was higher in skills and 4vs0 drills, while higher peak EL · min-1 values were obtained in 5vs5 and 5vs5-scrimmage. Similarly, EL · min-1 was higher when involvement % increased (p = 0.001), while there was an opposite trend for peak EL · min-1 (lower with higher involvement %). Court area per player influenced peak (p = 0.025) but not average demands. No effects were found for playing position or competition rotation status (all p > 0.05), except for a moderately higher EL · min-1 in starters compared to bench players. The external load intensities of basketball training drills substantially vary depending on the load indicator chosen, the training content, and task and individual constraints. Practitioners should not interchangeably use average and peak external intensity indicators to design training but considering them as separate constructs could help to gain a better understanding of basketball training and competition demands.

Effects of Acute Caffeine Ingestion on Cognitive Performance before and after Repeated Small-Sided Games in Professional Soccer Players: A Placebo-Controlled, Randomized Crossover Trial.

Soccer is a team sport that requires players to process a significant amount of information quickly and respond with both speed and accuracy to the ever-changing demands of the game. As such, success in soccer depends not only on physical attributes but also on cognitive abilities such as perception and decision-making. The aim of the current study was to investigate the acute effects of caffeine ingestion on Stroop test performance before and after repeated small-sided games (SSG) in professional soccer players. Twelve professional male soccer players (29 ± 4.1 years; 78.1 ± 7.7 kg body mass) participated in this study. A randomized crossover double-blind placebo-controlled trial was used. Caffeine (5 mg.kg-1) or a placebo was ingested 45 min before a protocol consisting of five 5 min SSG with 1 min rest intervals. A computerized version of the colour Stroop test was completed immediately before and after the exercise protocol. During the Stroop test, words appeared on the computer screen in three different ways: (i) neutral words (neutral condition); (ii) correspondent colour (i.e., "red" painted in red; congruent condition), or; (iii) different colour (i.e., "red" painted in green; incongruent condition). The incongruent condition aimed to cause the interference effect, as the colour and the word did not match. Ratings of perceived exertion (RPE) were assessed after each SSG. RPE increased during the five sets of the SSG protocol (p < 0.001), without differences between the caffeine and placebo trials. The soccer-specific exercise protocol promoted a faster response during the Stroop test (two-way ANOVA main effect for SSG protocol: p < 0.05), with no differences in accuracy (p > 0.05). Caffeine ingestion resulted in slower reaction time during the Stroop test during the congruent and neutral trials but not during the incongruent trial (two-way ANOVA main effect for supplementation: p = 0.009, p = 0.045, and p = 0.071, respectively). Accuracy was lower in the caffeine trial in congruent and incongruent trials (p < 0.05 caffeine vs. placebo both on the pre- and post-SSG protocol). In conclusion, a soccer-specific exercise protocol improved the Stroop test performance in professional soccer players, but acute caffeine ingestion (5 mg.kg-1) was detrimental.

Acute locomotor, heart rate and neuromuscular responses to added wearable resistance during soccer-specific training.

PURPOSE: Investigate acute locomotor, internal (heart rate (HR) and ratings of perceived exertion (RPE)) and neuromuscular responses to using wearable resistance loading for soccer-specific training. METHODS: Twenty-six footballers from a French 5th division team completed a 9-week parallel-group training intervention (intervention group: n = 14, control: n = 12). The intervention group trained with wearable resistance (200-g on each posterior, distal-calf) for full-training sessions on Day + 2, D + 4 and unloaded on D + 5. Between-group differences in locomotor (GPS) and internal load were analyzed for full-training sessions and game simulation drills. Neuromuscular status was evaluated using pre- and post-training box-to-box runs. Data were analyzed using linear mixed-modelling, effect size ±90% confidence limits (ES ± 90%CL) and magnitude-based decisions. RESULTS: Full-training sessions: Relative to the control, the wearable resistance group showed greater total distance (ES [lower, upper limits]: 0.25 [0.06, 0.44]), sprint distance (0.27 [0.08, 0.46]) and mechanical work (0.32 [0.13, 0.51]). Small game simulation (<190 m2/player): wearable resistance group showed small decreases in mechanical work (0.45 [0.14, 0.76]) and moderately lower average HR (0.68 [0.02, 1.34]). Large game simulation (>190 m2/player): no meaningful between-group differences were observed for all variables. Training induced small to moderate neuromuscular fatigue increases during post-training compared to pre-training box-to-box runs for both groups (Wearable resistance: 0.46 [0.31, 0.61], Control: 0.73 [0.53, 0.93]). CONCLUSION: For full training, wearable resistance induced higher locomotor responses, without affecting internal responses. Locomotor and internal outputs varied in response to game simulation size. Football-specific training with wearable resistance did not impact neuromuscular status differently than unloaded training.

School-Based TGfU Volleyball Intervention Improves Physical Fitness and Body Composition in Primary School Students: A Cluster-Randomized Trial.

This study aimed to explore whether a 16-week Teaching Games for Understanding (TGfU) volleyball intervention could improve primary school students' physical fitness and body composition. Eighty-eight primary school students (age 13.3 ± 0.3 years) were randomized to a TGfU volleyball intervention group (VG) or a control group (CG). The CG attended three regular physical education (PE) classes per week, while the VG attended two regular PE classes and a TGfU volleyball intervention that was implemented in the third PE class. Body composition components (body weight, body mass index, skinfold thickness, body fat percentage, and muscle mass percentage) and physical fitness (flexibility, vertical jumps (squat and countermovement jump-SJ/CMJ), 30 m sprint, agility, and cardiorespiratory fitness) assessments were performed pre-and post-intervention period. Significant interaction effects between VG and CG and pre- and post-test were found for the sum of five skinfolds (p < 0.0005, ŋp2 = 0.168), body fat % (p < 0.0005, ŋp2 = 0.200), muscle mass % (p < 0.0005, ŋp2 = 0.247), SJ (p = 0.002, ŋp2 = 0.103), CMJ (p = 0.001, ŋp2 = 0.120), 30 m sprint (p = 0.019, ŋp2 = 0.062), agility T-test (p < 0.0005, ŋp2 = 0.238), and VO2max (p < 0.0005, ŋp2 = 0.253). Further examination revealed a greater improvement among VG students compared to CG students in certain body composition and physical fitness outcomes. Implementing a TGfU volleyball intervention in the physical education curriculum appears to have effective stimuli for reducing adiposity and promoting physical fitness levels in seventh-grade primary school students.

Recreational Football Training Increases Leg-Extensor Velocity Production in 55- To 70-Year Old Adults: A Randomized Controlled Trial.

This study investigated the effects of 10 weeks of recreational football training on the leg-extensor force-velocity (F-V) profile in 55- to 70-year-old adults. Simultaneous effects on functional capacity, body composition and endurance exercise capacity were examined. Forty participants (age 63.5 ± 3.9 years; 36♂ 4♀) were randomized in a football training (FOOT, n = 20) and a control (CON, n = 20) group. FOOT performed 45-min to 1-h of football training sessions with small-sided games twice a week. Pre- and post-intervention assessments were performed. The results revealed a greater increase in maximal velocity (d = 0.62, pint = 0.043) in FOOT compared to CON. No interaction effects were found for maximal power and force (pint > 0.05). 10-m fast walk improved more (d = 1.39, pint < 0.001), 3-step stair ascent power (d = 0.73, pint = 0.053) and body fat percentage (d = 0.61, pint = 0.083) tended to improve more in FOOT than in CON. RPE and HR values at the highest speed level during a submaximal graded treadmill test decreased more in FOOT compared to CON (RPE: d = 0.96, pint = 0.005; HR: d = 1.07, pint = 0.004). Both the number of accelerations and decelerations as well as the distance spent in moderate- and high-speed zones increased markedly throughout the 10-week period (p < 0.05). Participants perceived the sessions as very enjoyable and feasible. In conclusion, recreational football training resulted in improved leg-extensor velocity production, which translated to a better performance on functional capacity tests that rely on a high execution velocity. Simultaneously, exercise tolerance was improved and body fat percentage tended to reduce. It appears that short-term recreational football training can induce broad-spectrum health benefits in 55- to 70-year-old adults with only 2 hours of training per week.

Internal and External Loads of Young Elite Soccer Players during Defensive Small-Sided Games.

The aim of this study was to evaluate the effects of different time periods on the internal and external loads of soccer players during small-sided games (SSGs). Seventeen young soccer players performed a SSG of 5 vs. 5 + 5 with 2 floaters, where two teams had possession of the ball, and one had to recover it. With established periods of 30 s (SSG30), 1 min (SSG1) or 2 min (SSG2), teams participated in a defensive role for these periods of time. Total distance covered, moderate speed running distance, high speed running distance, sprint running distance, accelerations, decelerations and Player Load were monitored using global positioning systems devices. The maximal heart rate and modified training impulse were monitored using heart rate monitors. The rating of perceived exertion (RPE) was also measured. Data showed a small increase between SSG30 and SSG1 in Player Load (ES = -0.35; p < 0.01), and a small increase in high speed running (ES = -0.41; p < 0.05) and sprinting (ES = -0.47; p < 0.01) between SSG30 and SSG2. Also, SSG1 showed a small increase in sprinting (ES = -0.57; p < 0.01) and accelerations (ES = -0.37; p < 0.05) with respect to SSG2. In addition, SSG2 showed a small increase in the RPE with respect to SSG30 (ES = 0.46; p < 0.05). The results indicate that shorter defensive periods in SSGs increased high speed running, while longer defensive periods promoted greater perceived exertion. Manipulation of the duration of defensive periods in SSGs is a variable that should be considered in soccer training.

Kinematic parameters and metabolic power in elite soccer players: A small sided a large sided games comparison.

Introduction: The goal of this paper is to determine what happens in one minute (on average) in kinematic parameters and metabolic power in small sided games (SSG) (3v3; 5v5) and large sided games (LSG) (10v10) and in which games kinematic parameters and metabolic power are best developed. Methods: The participants of this study were 22 professional football players, height 182.95±6.52 cm, mass 77.17±8.21 kg, body mass index (BMI) 22.97±1.47 kg/m2, body fat 9.85±2.55 %, aged 27.1±5.4 yrs, who played in the Premier League of Bosnia and Herzegovina. Data total distance (TD), maximum speed (MS), number of accelerations (nAcc), number of decelerations (nDec), number of sprints (nS), high intensity distance (Z4≥19.8 km/h), sprint distance (Z5≥25.2 km/h) and movements requiring a certain metabolic power (Pmet), were collected using a 20 Hz Global positioning system (GPS) system Pro2 (GPEXE, Exelio srl, Udine, Italy), on a total of 307 individual observations. Results: The results showed that the average total distance was significantly higher in the 5v5 (135.16±18.78 m) and 10v10 (133.43±20.06 m) games (F=64.26, p<0.001) compared to the 3v3 (108.24±11.26 m). Furthermore, the values of the variables Z4 (8.32±3.38 m, F=97.59), Z5 (1.84±1.53 m, F=123.64), nS (0.13±0.10 n, F=96.14) as well as Maxspeed (27.06±1.90 km/h, F=139.33), are statistically significantly higher (p<0.001) in the 10v10 game compared to the other two game formats. The average number of nAcc (0.40±0.32 n, F=9.86, p<0.001) and nDec (0.62±0.36 n, F=6.42, p<0.001) is statistically significantly higher in the 5v5 game. The results showed that the 5v5 game is significantly more metabolically demanding Pmet (2.76±0.67 W•kg-1, F=66.08, p<0.001) compared to the other two game formats. Discussion: The data presented in this paper can be used as a basis for the construction of specific exercises based on kinematic and physiological requirements, and for planning and programming microcycles in football.

New Zealand Youth Rugby Sevens: A Comparative Match Demands Study.

Rugby sevens has established itself on the world stage since its inclusion in the 2016 Olympics. Participation among New Zealand (NZ) youth has surged. Sevens games have specific high demands, but little is known about these competitive demands in regards to youth. Two NZ male youth squads (U15, n = 13; U19, n = 14) were monitored during a national sevens tournament. Microsensor technology captured heart rate (HR) and kinematic performance. The rating of perceived exertion (RPE) was collected for U15 matches only. U19 and U15 players ran 108 ± 11 and 116 ± 13 m·min-1 at an average speed (VAVG) of 6.5 ± 0.6 and 6.9 ± 0.8 km·h-1. Peak speeds (VPEAK) reached 33.7 km·h-1, and high-intensity running distance (HIRD) averaged 252 ± 102 m. U15 (44.3 ± 9.2 game-1) and U19 (39.4 ± 6.1 game-1) showed different sprint rates. U15 covered more moderate-velocity distance (20-80% VMAX) and less low-velocity distance (<20% VMAX). RPE was 13 ± 1 (U15). An average HR of 90.0 ± 3.9% HRMAX was recorded. Upwards of 57% of game time was played at >95% HRMAX. Youth sevens competition is specifically demanding. U15 can experience greater loads than older peers in rugby. Coaches can use this information to optimize players' physical development.

The Influence of Pitch Dimensions during Small-Sided Games to Reach Match Physical and Physiological Demands on the Youth Soccer Players.

The aims of this study were to (i) analyze the physical and physiological responses of four matches competition and (ii) to investigate the relationships among three different pitch dimensions of small-sided game (SSG) on the youth soccer players. Fifteen male U19 soccer players (age 17.3 ± 0.5 years, height 175.7 ± 5.6 cm, weight 68.5 ± 8.6 kg, playing experience 7.8 ± 1.4 years) were randomly assigned to three play areas: small (50 m2), medium (SSG-m, 150 m2) and large (SSG-l, 250 m2) area per player including goalkeeper. During the 4-week intervention, both groups performed three sets of 8 min with a passive rest period of 5 min between games. Differences in time-motion characteristics of players were measured with the Global Positioning System and assessed using a repeated measures ANOVA to compare the three game conditions and the magnitude-based inference to evaluate the pairwise comparison effects. The results showed that only the variables distance covered between 7.0-12.9 km·h-1 was not statistically significantly different among game conditions (p < 0.05; η = 0.21; small) and physiological response (i.e., hear rate of playing time spent 85-89% HRmax) also showed differences (p < 0.05; η = 0.25; small). The responses in SSG-m and SSG-l established them ass the format sizes ideal for replicating the physical responses during match competition. These findings could provide relevant information for coaches for use adequate pitch size (areas of 150 m2 and 250 m2) to reach the match-play scenarios found in match competition.