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OBJECTIVES: The aims of this study were to analyze the relationships between minutes of play (MP) and maturity status, fitness, and hormonal levels and to explain how those measures influence the time of play. METHODS: Twenty-six youth soccer players U15 participated in this study over a full-season period. Anthropometric measures, maturity status, growth hormone (GH), insulin-like growth factor and physical levels such as maximal oxygen uptake (VO2max), fatigue index, countermovement jump (CMJ) performance were collected. At the end-season, players were assessed in 6 different tests over four days. RESULTS: VO2max largely correlated with GH (r = 0.57) and CMJ (r = 0.51). Also, GH largely correlated with CMJ (r = 0.55). MP had moderate correlations with VO2max (r = 0.44) and CMJ (r = 0.42). Multiple linear regression with maturation, physical fitness and hormonal levels explained R2 of 0.62 of the MP (F (8, 17) = 3.47, p = 0.015). Although each independent variable alone was not able to determine the playing time, when using the interactions, the model significantly explained the MP. CONCLUSIONS: The combination of maturity status, physical fitness, and hormonal levels seem to play a determinant role in explaining the match participation in youth soccer players.
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Desempenho Atlético , Hormônio do Crescimento Humano , Futebol , Adolescente , Exercício Físico , Humanos , Masculino , Aptidão Física , Estudos ProspectivosRESUMO
Background and Objectives: The aim of this study was twofold: (i) to analyze the relationships between fitness status (repeated-sprint ability (RSA), aerobic performance, vertical height jump, and hip adductor and abductor strength) and match running performance in adult women soccer players and (ii) to explain variations in standardized total distance, HSR, and sprinting distances based on players' fitness status. Materials and Methods: The study followed a cohort design. Twenty-two Portuguese women soccer players competing at the first-league level were monitored for 22 weeks. These players were tested three times during the cohort period. The measured parameters included isometric strength (hip adductor and abductor), vertical jump (squat and countermovement jump), linear sprint (10 and 30 m), change-of-direction (COD), repeated sprints (6 × 35 m), and intermittent endurance (Yo-Yo intermittent recovery test level 1). Data were also collected for several match running performance indicators (total distance covered and distance at different speed zones, accelerations/decelerations, maximum sprinting speed, and number of sprints) in 10 matches during the cohort. Results: Maximal linear sprint bouts presented large to very large correlations with explosive match-play actions (accelerations, decelerations, and sprint occurrences; r = -0.80 to -0.61). In addition, jump modalities and COD ability significantly predicted, respectively, in-game high-intensity accelerations (r = 0.69 to 0.75; R2 = 25%) and decelerations (r = -0.78 to -0.50; R2 = 23-24%). Furthermore, COD had significant explanatory power related to match running performance variance regardless of whether the testing and match performance outcomes were computed a few or several days apart. Conclusion: The present investigation can help conditioning professionals working with senior women soccer players to prescribe effective fitness tests to improve their forecasts of locomotor performance.
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Desempenho Atlético , Corrida , Futebol , Adulto , Estudos de Coortes , Teste de Esforço , Feminino , HumanosRESUMO
Optimizing athlete's performance is one of the most important and challenging aspects of coaching. Physiological and positional data, often acquired using wearable devices, have been useful to identify patterns, thus leading to a better understanding of the game and, consequently, providing the opportunity to improve the athletic performance. Even though there is a panoply of research in pattern recognition, there is a gap when it comes to non-controlled environments, as during sports training and competition. This research paper combines the use of physiological and positional data as sequential features of different artificial intelligence approaches for action recognition in a real match context, adopting futsal as its case study. The traditional artificial neural networks (ANN) is compared with a deep learning method, Long Short-Term Memory Network, and also with the Dynamic Bayesian Mixture Model, which is an ensemble classification method. The methods were used to process all data sequences, which allowed to determine, based on the balance between precision and recall, that Dynamic Bayesian Mixture Model presents a superior performance, with an F1 score of 80.54% against the 33.31% achieved by the Long Short-Term Memory Network and 14.74% achieved by ANN.
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Desempenho Atlético , Aprendizado Profundo , Reconhecimento Automatizado de Padrão , Dispositivos Eletrônicos Vestíveis , Teorema de Bayes , Humanos , Redes Neurais de Computação , EsportesRESUMO
This study aimed to observe the intraseasonal stability of anthropometric, technical and functional test results in academy soccer players of different age categories. In total, 103 participants (age range: 7.7-13.4 years) by 5 age categories of the same academy were recruited for this study. Players were submitted to a field-test battery comprising 3 anthropometric measurements (body mass, stature and body mass index), 6 soccer technical tests (to assess the ability of ball control, ball control with the head, pass accuracy, shooting accuracy, dribbling and dribbling with pass) and 3 functional tests (countermovement jump with the hands on the hip, countermovement jump with free hands and 15-m linear sprint) that was administered in 4 test sessions during the same season. Though anthropometric results showed a clear increment in each age category across the season, the fluctuation of technical test results depended on age category and test session. Moreover, a significant increase in the results of functional tests was observed in most of the age categories, in particular, for the assessment of lower power limb. In conclusion, collecting repeated intraseason measurements permits the identification of players' fluctuations of performance across the season and allows coaches to make frequent adjustments of their programmes.
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Desempenho Atlético , Destreza Motora , Movimento , Força Muscular , Aptidão Física , Corrida , Futebol , Adolescente , Antropometria , Criança , Teste de Esforço , Humanos , Extremidade Inferior , Masculino , Estações do AnoRESUMO
The aim of this study was to analyse the association between physical/technical variables and the tactical prominence variables in U14 soccer matches. Twenty-two young amateur soccer players (13.5 [Formula: see text] 0.5 years old, 5.4 [Formula: see text] 0.5 years of practice, 163.3 [Formula: see text] 9.8 cm in body height) from two teams of the Portuguese regional league volunteered for the study. Our results showed positive and moderate correlation between dribbling test and betweenness centrality (r = 0.324; p = 0.142), and negative moderate correlation between %fatigue index and betweenness centrality (r = -0.390; p = 0.073). Physical and technical variables had no statistical differences among tactical positions. Nevertheless, when tactical prominence of players from four tactical positions were compared, significant differences were found in terms of degree prestige (p = 0.001) and degree centrality (p = 0.002). This pilot study did not find strong correlations between physical/technical levels and tactical prominence in soccer matches.
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Desempenho Atlético/fisiologia , Desempenho Atlético/psicologia , Comportamento Competitivo , Futebol/fisiologia , Futebol/psicologia , Adolescente , Teste de Esforço , Humanos , Projetos Piloto , PortugalRESUMO
Studies have provided empirical evidence on the prognostic relevance of test batteries and the "coach's eye" for talent identification. The aims were 1) to compare objective and subjective assessments as well as a combined soccer-specific potential index between future selected and non-selected players and 2) to evaluate the prognostic validity of a multidimensional model as a tool for talent identification in soccer. The sample was composed by 132 male players (14,5 ± 1,4 years; regional competitive level) from U13 to U17 age groups of a Brazilian soccer talent development program. Athletes completed a multidimensional test battery and were subjectively rated by their coaches for sporting potential. Players' success was evaluated five years later and was operationalized by achieving under-20 category of the Brazilian Championship or adult professional level (success rate, 15.9%). Confirming univariate prognostic validity, future selected outperformed non-selected players regarding 20-m sprint (p = .009), agility (p = .04), countermovement jump (p = .04), sit-and-reach (p = .001), Yo-Yo IR1 (p = .001), dribbling (p < .001), perceived competence (p = .007), peaking under pressure (p = .01), confidence/motivation (p = .03), coping skills (p = .03), intangibles (p < .001) and player potential (p < .001). A combined index (objective tests, athlete's assessments and coach's eye) named Gold Score Soccer (GSS) showed high prognostic validity (p < .001). A binary logistic regression estimated the probability of success (yes/not) with GSS, ambidextrous and predicted age at peak height velocity as predictors. This multidimensional model named GoldFit Soccer showed high prognostic validity (sensitivity = 85.7%; specificity = 83.8%; accuracy = 84.1%; area under the ROC curve = .93 [.87-.98]). Thus, GoldFit Soccer is a valid multidimensional scientific model for talent identification in soccer.
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The purpose of this study was to determine the differences in functional capacities and hormonal indices according to biological maturity and seasonal playing time status in young soccer players. Twenty-three male under-15 players (14.6 ± 0.2 years) were divided into two groups, based on their maturity status and seasonal playing time. They were measured for anthropometrics, Yo-Yo intermittent recovery level 1 (YYIR1), seven repeated sprint test (7RST), countermovement jump (CMJ), skeletal age, growth hormone, and insulin-like growth factor-1 (IGF-1) level. Age at peak height velocity (APHV) was determined to estimate the maturity timing. The results revealed that players who advanced in maturation were significantly heavier (p = 0.029) and had higher values in skeletal age (p < 0.001), sitting height (p = 0.005), CMJ (p = 0.038), and IGF-1 (p = 0.013). Players given greater playing time exhibited significantly lower fatigue index (p = 0.012), but higher CMJ (p = 0.003) and IGF-1 (p = 0.001) values. The overall results highlighted that early-maturing players and players with greater playing time obtained higher values in both CMJ and IGF-1. The findings may provide an insight on the coaches' evaluation of players and on the possible factors that may affect the future playing status of young male soccer players.
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Desempenho Atlético , Corrida , Futebol , Adolescente , Humanos , Fator de Crescimento Insulin-Like I , Masculino , Aptidão FísicaRESUMO
The purpose of this study was to evaluate the strength of the knee flexors and extensors and hip abductor and adductor muscles in young soccer players. Twenty-three male under-19 soccer players participated in this study (age: 17.7 ± 0.2 years; height: 173.0 ± 1.1 cm; body mass: 66.1 ± 1.3 kg). Body composition was measured using a bioelectrical impedance (InBody770), and the dynamometry was performed by an isokinetic dynamometer (Biodex System 3) for knee flexion and extension, and by an isometric dynamometer (Smart Groin Trainer), for hip adduction and abduction. Comparisons were made between dominant members (D) vs. non-dominant members (ND) and adductors vs. abductors (ADD:ABD) using the Wilcoxon test. There were statistically significant differences in the peak torques between the dominant and non-dominant members in the flexion function (Z = -4.198, p < 0.01) and in the extension function (Z = -4.197, p < 0.01) of the knee in concentric muscular action, and the flexion (Z = -4.198, p < 0.01) and in the extension (Z = -4.198, p < 0.01) of the knee in eccentric muscular action. No statistically significant differences were obtained in the conventional ratio (Z = -0.456, p = 0.648) nor the functional ratio (Z = -0.335, p = 0.738) between D and ND members. There were no statistically significant differences between adductors and abductors at the moment of strength for absolute values (N). The reference absolute and normalized to the weight values and the ADD:ABD can be used as a guideline for classifying players in screening and comparison in return tests to sports practice after an injury.
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Futebol , Adolescente , Humanos , Joelho/fisiologia , Articulação do Joelho , Masculino , Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Futebol/fisiologia , TorqueRESUMO
BACKGROUND: The main purpose of this study was to investigate the relationships between minutes played (MP) with maturity status, fitness, and hormonal levels, and to quantify their influence on minutes played. METHODS: Twenty-four elite youth soccer players under-16 years participated in this study, over a full-season period. Anthropometric measures, maturity status, hormonal and physical fitness levels were collected. Participants were monitored during the season. After the end-season, players were assessed in 6 different tests over a four-day period. RESULTS: The maximum oxygen consumption (VÌO2max) was strongly correlated with MP (r = 0.75), maturity offset (r = 0.52), and countermovement jump (r = 0.53). Multiple linear regression explained 76% of MP (F (8, 15) = 6.05, p = 0.001), with an R2 of 0.76. Moreover, Growth hormone (GH) and VÌO2max. were the most influential factors in MP (F (2, 21) = 17.92, p ≤ 0.001), with an R2 of 0.63. CONCLUSION: High levels of GH and VÌO2max have a preponderant role in MP by elite youth soccer players, it appears to be more pragmatic to consider other contextual dimensions, as they can impact selection for competition and minutes of participation in a match.
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This study examined the relationship between maturation and signal detection skills, as well as the effect of signal detection on the tactical behavior efficiency of young soccer players. Fifty-four male soccer players participated in the study (U-11, U-13, and U-15). Maturation was evaluated by the Khamis-Roche method, and peak height velocity was estimated. A computer-based test in the Vienna Test System® was used to assess signal detection skills, whereas tactical behavior efficiency was assessed using the System of Tactical Assessment in Soccer. Descriptive analysis, the Kolmogorov-Smirnov test, the Spearman bivariate correlation and the univariate analysis of variance (one-way ANOVA) were performed. Effect sizes were reported as Cohen's d, and the significance level was set at p < .05. Relationships were observed between the percentage of predicted adult height and signal detection performance. Also, signal detection skills were found to affect the tactical behavior efficiency of young soccer players. It is concluded that the players, as seen more mature, can perceive the game faster and more effectively, and are able to provide quicker responses in the game context.
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Desempenho Atlético , Futebol , Análise de Variância , Desempenho Atlético/fisiologia , Estatura , Humanos , Masculino , Futebol/fisiologiaRESUMO
The aim of this cohort study was two-fold: (i) to analyze within-group changes of final velocity in a 30-15 intermittent fitness test (VIFT), final velocity in a Vameval test (Vvameval), 20-m sprint and countermovement jump (CMJ); (ii) to explore the relationships between VIFT and Vvameval outcomes and their changes with internal and external loads. Twenty-two professional soccer players (mean ± SD; age 27.2 ± 3.4 years, height 174.2 ± 3.6 cm, body mass 69.1 ± 6.4 kg, and body fat 10.4 ± 4.1%, 3.1 ± 1.5 years in the club) participated in this study. External and internal loads were obtained using global positioning system, heart rate and rate of perceived effort (sRPE) after each training session. Players were assessed in CMJ, 20-m sprint, Vameval and 30-15 intermittent fitness test, before and after the observed period. Very large relationships were observed between VIFT and Vameval for pre- (r = 0.76), post (r = 0.80) and pooled-data (r = 0.81). Vvameval showed less sensitivity (-22.4%, [-45.0 to 9.4]), ES -0.45 [-1.05 to 0.16]) than VIFT. ∆VIFT had unclear associations with all sRPE, but had moderate correlations with objective internal and external measures, while, ∆Vvameval varied between large and very large relationships with all sRPE, but had unclear associations with all other selected training loads. Objective internal and external loads may be used to track aerobic power related changes from VIFT.
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Futebol , Adulto , Estudos de Coortes , Sistemas de Informação Geográfica , Frequência Cardíaca , Humanos , Aptidão Física , Adulto JovemRESUMO
The purposes of this study were (1) to analyze between-session variations of external and internal load measures during small-sided games (SSGs) and (2) to test the relationships between the maximum speed reached (VIFT) during the last stage of the 30-15 Intermittent Fitness Test, hemoglobin levels, and training load measures during SSG intervals among professional soccer players. Sixteen professional soccer players (mean ± SD; age 27.2 ± 3.4 years, height 174.2 ± 3.6 cm, body mass 69.1 ± 6.4 kg, and body fat 10.4 ± 4.1%) participated in this study. Hemoglobin and aerobic performance were first tested, and then a 3-week SSG program was applied using a 3 vs. 3 format. During those 3 weeks, internal and external load of entire sessions were also monitored for all training sessions. Trivial-to-small, standardized differences were observed between sessions for external and internal measures during SSGs. Total distance (TD) and mechanical work (MW) were the only variables that indicated small changes. Large-to-very-large relationships were found between VIFT and external loads: TD (r range: 0.69; 0.87), high-intensity running (HIR; r range: 0.66; 0.75), and MW (r range: 0.56; 0.68). Moderate-to-large negative relationships were found between hemoglobin levels and internal loads: Edwards' TRIMP (r range: -0.36; -0.63), %HRmax (r range: -0.50; -0.61), and red zone (r range: -0.50; -0.61). VIFT had unclear relationships with overall internal loads, while hemoglobin levels presented unclear relationships with overall external loads. In conclusion, no meaningful changes were found between sessions considering the format of play used. Additionally, the detected relationships indicate that VIFT and hemoglobin levels are good indicators of the performance capacity and physiological profile of players during SSGs. Also, the use of SSGs protocols as a monitoring complement of the 30-15IFT is suggested.
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Studies assessing age and maturation effects on morphological and physical performance measures of young judokas are scarce. This study aimed to assess the independent and combined effects of chronological age and biological maturation on anthropometry and physical performance of 67 judokas aged 11-14. Participants' anthropometric profiles were assessed, and physical performance tests were completed. Multivariate analyses of variance revealed an independent effect of age (anthropometry: F = 1.871; p < 0.05; Pillai's trace = 0.545; η2 p = 0.272; physical performance: F = 2.876; p < 0.01; Pillai's trace = 0.509; η2 p = 0.254) and maturity (anthropometry: F = 10.085; p < 0.01; Pillai's trace = 0.669; η2 p = 0.669; physical performance: F = 11.700; p < 0.01; Pillai's trace = 0.581; η2 p = 0.581). There was no significant combined effect of age and maturity. The maturation effect remained significant when controlled for age (anthropometry: F = 4.097; p < 0.01; Pillai's trace = 0.481; η2 p = 0.481; physical performance: F = 3.859; p < 0.01; Pillai's trace = 0.0.318; η2 p = 0.318). Inadolescent judokas, the maturation effect on growth and physical performance seems to be more relevant than the age effect, leading to the need to control this effect in training routines and competitive events. As in studies with youth soccer players and other youth athletes, bio-banding can be a strategy for controlling maturation in combat sports.
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This study aimed to analyze the variations of fitness status, as well as test the relationships between accumulated training load and fitness changes in women soccer players. This study followed an observational analytic cohort design. Observations were conducted over 23 consecutive weeks (from the preseason to the midseason). Twenty-two women soccer players from the same first Portuguese league team (22.7 ± 5.21 years old) took part in the study. The fitness assessment included anthropometry, hip adductor and abductor strength, vertical jump, change of direction, linear speed, repeated sprint ability, and the Yo-Yo intermittent recovery test. The training load was monitored daily using session rating of perceived exertion (s-RPE). A one-way repeated ANOVA revealed no significant differences for any of the variables analyzed across the three moments of fitness assessments (p > 0.05). The t-test also revealed no differences in the training load across the moments of the season (t = 1.216; p = 0.235). No significant correlations were found between fitness levels and accumulated training load (range: r = 0.023 to -0.447; p > 0.05). This study revealed no differences in the fitness status during the analyzed season, and the fitness status had no significant relationship with accumulated training load.
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Condicionamento Físico Humano , Corrida , Futebol , Adolescente , Adulto , Teste de Esforço , Feminino , Humanos , Aptidão Física , Estações do Ano , Adulto JovemRESUMO
This study examined the effect of a competitive season on salivary responses [cortisol (sC), testosterone (sT), Testosterone/Cortisol ratio (sT/C), Immunoglobulin A (sIgA), sIgA secretion rate (srIgA), alpha-amylase (sAA)] and upper respiratory symptoms (URS) occurrence in three teams of male soccer players (Under-15, Under-17 and Under-19 yrs.). Training and competition volumes, salivary biomarkers and URS were determined monthly. No differences were found for monthly training volume between teams. Incidence of URS was higher for the U15 (44.9% of the total cases). Higher sT and srIgA were observed for the U19, lower sC were found for the U17 and sAA showed higher values for the U15 throughout the season. In the U15, significant difference (p = .023) was found for sIgA concentration with higher concentration values in January compared to December (-42.7%; p = .008) and the sT showed seasonal variation (p < .001) with the highest value in January significantly different from October (-40.2%; p = .035), November (-38.5%; p = 0.022) and December (-51.6%; p = .008). The U19 presented an increase in sC in March compared to February (-66.1%, p = .018), sT/C were higher in February compared to March (-58.1%; p = .022) and sAA increased in March compared to September (-20.5%; p = .037). Negative correlations, controlled for age group, were found between URS occurrence and srIgA (r = -0.170, p = .001), sAA (r = -0.179, p = .001) and sT (r = -0.107, p = .047). Monitoring salivary biomarkers provides information on mucosal immunity with impact in URS occurrence. Coaches could manipulate training loads to attenuate the physical stressors imposed on athletes, especially at demanding and stressful periods.
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Atletas , Imunidade nas Mucosas , Doenças Respiratórias/imunologia , Saliva/imunologia , Futebol , Adolescente , Biomarcadores/metabolismo , Humanos , Hidrocortisona/metabolismo , Imunoglobulina A Secretora/metabolismo , Masculino , Estações do Ano , Testosterona/metabolismo , alfa-Amilases/metabolismoRESUMO
RESUMO Este artigo tem como objetivo principal analisar o financiamento público do esporte no Brasil e Portugal, a partir do indicador de magnitude dos recursos públicos destinados ao setor entre 2004 e 2020, bem como comparar os valores per capita investidos no esporte por estes países. Caracteriza-se como uma pesquisa descritivo-analítica de abordagem qualitativa e abrangência exploratória, baseada em processo científico realizado em três etapas: a) fase exploratória; b) trabalho de campo; e c) análise e tratamento do material empírico e documental. Os países apresentaram em comum um baixo percentual do orçamento geral dedicado ao esporte e aquém de proposições de representações coletivas do setor, além de um comportamento descendente de gastos com o esporte em período recente.
ABSTRACT This article aims to analyze the public funding of sport in Brazil and Portugal, from the indicator of magnitude of public resources allocated to the sector between 2004 and 2020, as well as to compare the per capita amounts invested in sport by these countries. It is characterized as a descriptive-analytical research of qualitative approach and exploratory scope, based on a scientific process carried out in three stages: a) exploratory phase; b) field work; and c) analysis and treatment of empirical and documentary material. The countries presented in common a low percentage of the general budget dedicated to sport and short of propositions of collective representations of the sector, in addition to a pattern of spending on sport in the recent period.
RESUMEN El principal objetivo de este artículo es analizar la financiación pública del deporte en Brasil y Portugal, a partir del indicador de la magnitud de los recursos públicos destinados al sector entre 2004 y 2020, así como comparar los importes per cápita invertidos en el deporte. por estos países. Se caracteriza por ser una investigación descriptivo-analítica con enfoque cualitativo y alcance exploratorio, basada en un proceso científico realizado en tres etapas: a) fase exploratoria; b) trabajo de campo; yc) análisis y tratamiento de material empírico y documental. Los países tenían en común un bajo porcentaje del presupuesto general dedicado al deporte y escaso de propuestas de representaciones colectivas del sector, además de una tendencia a la baja del gasto en deporte en los últimos tiempos.
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This study is focused on the strategies adopted by Italian 'Serie A' soccer clubs during the non-competitive period. Thus, duration (i.e., number of days) of the specific non-competitive periods (i.e., off- plus pre-season, off-season, pre-season, summer camp), the number of games (i.e., friendly, official and polled games) and days between games (i.e., ≤ 3, 4-5, or ≥ 6 days between two consecutive games) of the entire non-competitive period were recorded and compared by clubs participating in the European Championships (EU), only 'Serie A' (A) and promoted from 'Serie B' (B) during five and single seasons (i.e., 2009/10-2013/14). Due to the short B off-season duration (2009/10-2013/14, 2010/11, 2011/12, 2012/13, 2013/14, p≤.001), effects between clubs emerged also for the off- plus preseason (2009/10-2013/14, EU vs A, p≤.01, EU vs B, p≤.01, A vs B, p≤.001; 2011/12, 2012/13, 2013/14, p≤.001). Nevertheless, no difference between clubs resulted for the pre-season. Reduced duration of summer camps was reported by the EU (i.e., 2009/10-2013/14, 2009/10, 2013/14, p≤.001). A higher number of official games were played by EU than A (i.e., 2009/10-2013/14, p≤.001; 2010/11, p≤.01). No effect emerged for the days between games. Therefore, despite the longer 'Serie B' schedule and EU preliminary UEFA games that determined the off-season restriction, clubs demonstrated the tendency to guarantee satisfactory pre-season duration.
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Studies focused on position-related characteristics of young soccer players often ignore the goalkeepers. The aim of this study was to examine the effect of playing position on anthropometry, physiological attributes, soccer skills, and goal orientation across adolescence. One hundred forty-five soccer players age 11-19 y were assessed in training experience, body size, maturation, physiological parameters, soccer skills, and goal orientation. Factorial ANOVA was used to test the effect of age group, playing position, and respective interaction terms, while analysis of variance was used to compare goalkeepers vs outfielders in middle (under 13 [U-13] and U-15) and late (U-17 and U-19) adolescence. Discriminant analysis was used to identify the variables that contributed to explaining playing positions. Age group was a consistent source of variation for all variables except task and ego orientations. Fat mass, agility, endurance, dribbling speed, shooting accuracy, and passing were affected by the gradient derived from the classification between goalkeepers and outfielders. It was possible to correctly classify the playing position based on fat-free mass and 3 manipulative skills in younger players and on 4 skills in U-17 and U-19 soccer players. Future research should include longitudinal information to improve our understanding of the factors that contribute to distinguish goalkeepers from outfielders.
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Antropometria , Desempenho Atlético/fisiologia , Destreza Motora/fisiologia , Futebol/fisiologia , Adolescente , Fatores Etários , Tamanho Corporal , Criança , Estudos Transversais , Humanos , Masculino , Maturidade SexualRESUMO
Abstract There is growing interest in identifying morphological, motor, maturation characteristics, as well as their changes, of children and adolescents in systematized training in various sports. Knowledge of these characteristics is important for coaches and researchers because they provide parameters for assessing youth development during training. For track and field, studies on the category under 16 are scarce. Thus, the objectives of this study are to describe the profile and to design a percentile table of morphological, motor, maturation and event-specific variables of under 16 athletes. 105 young athletes were evaluated on two consecutive days. On the first day, an anamnesis of athletes and coaches was performed. Anthropometric and anaerobic measurements were analyzed in shot put, long jump, 800 m run. On the second day, flexibility, vertical impulse, upper limb strength, speed and maximal aerobic speed were evaluated. The biological maturation was evaluated by the percentage of the predicted height. A table with percentiles was prepared with the data of all athletes. Another table with the results of the whole group plus mean and standard deviation was prepared. A last table was prepared containing data divided by group of sports events. The morphological variables presented differences between the groups as to body mass, BMI and sum of skinfolds. Significant differences were observed only for the motor variable VMA. No significant differences were observed only for long jump. When divided by groups, it was evident that throwers are different from the other athletes in some morphologic variables and in specific sports events.
Resumo É crescente o interesse em identificar características morfológicas, motoras e maturacionais, bem como suas modificações em crianças e adolescentes inseridos em treinamentos sistematizados nas mais variadas modalidades esportivas. O conhecimento dessas características é importante para que treinadores e pesquisadores tenham parâmetros de avaliação do desenvolvimento do jovem durante o treinamento. Para o atletismo, são limitados estudos para a categoria sub 16. Desta forma, os objetivos são, descrever o perfil e elaborar uma tabela de percentil das variáveis morfológicas, motoras, maturacionais e de provas específicas de atletas sub 16. Foram avaliadas 105 jovens atletas em dois dias consecutivos. No primeiro dia, foi realizada a anamnese nos atletas e treinadores, medidas antropométricas, anaeróbicas e as provas do arremesso de peso, salto em distância, corrida de 800m. No segundo dia, foi avaliada a flexibilidade, impulsão vertical, força de membro superior, velocidade e velocidade aeróbia máxima. A maturação biológica foi avaliada pelo percentual da estatura predita. Foram elaboradas uma de percentis com resultado de todas as atletas, outra com média e desvio padrão com os resultados do grupo todo e uma última dividida por grupo de provas. Nas variáveis morfológicas foram encontradas diferenças entres os grupos para a massa corporal, IMC e somatório de dobras, nas motoras apenas na VMA e nas provas específicas não foi observada diferença significativa apenas salto em distância. Quando dividido pelos grupos, se evidenciou que as lançadoras são diferentes das demais atletas em algumas variáveis moforlógicas e nas provas específicas.