The effects of body size and training environment on the physical performance of adolescent basketball players: the INEX study.

BACKGROUND: Although adolescent basketballers differ in body size, shape, and composition, less is known about how these factors interact during physical development. AIM: We used ontogenetic allometry to identify the optimal body size and shape characteristics associated with physical performance in adolescent basketball players, and investigated the effects of training experience, training volume, maturity status, and club characteristics on physical performance development. SUBJECTS AND METHODS: Two hundred and sixty-four male basketballers, from five age-cohorts (11-15 years of age), were followed consecutively over three years. Three physical performance components, anthropometrics, training information, and biological maturation were assessed bi-annually. Longitudinal multiplicative allometric models were developed. RESULTS: Players with a physique that had a dominant ectomorphic component performed better in all physical performance components. When adjusting for confounders other than size, the development of running speed was independent of body size. Players advanced in maturation were physically fitter. Training data had no significant effect on developmental trajectories of running speed or lower body explosive strength. Club characteristics had no significant association with any physical performance trajectories. CONCLUSION: Leaner players have advantages in physical performance and individual characteristics play an important role, over and beyond club structure, in developing physical performance.

The role of growth, maturation and sporting environment on the development of performance and technical and tactical skills in youth basketball players: The INEX study.

In this paper, we outline a systematic testing programme developed to help identify excellence in youth basketball players. We examine the links between biological maturation and training experience with anthropometry, body composition, physical performance, technical and tactical skills from five age-cohorts, and characterize, in detail, facets of their environment. In total, 238 young basketball players aged 11-15 years, clustered into five age-cohorts (11, 12, 13, 14, 15 years) were recruited. We assessed measures across three domains: (1) biological [anthropometry, body composition, biological maturation and physical performance]; (2) skill/game proficiency [technical skills and tactical skills]; and (3) contextual [family support, coach knowledge and competence and club context]. The data were analysed using one-way ANOVAs and multivariate analysis of covariance adjusting for biological maturation and training experience. We report significant differences favouring older basketball players on most biological and skill/game proficiency variables. However, differences between age-cohorts in physical performance and technical skills were mitigated after controlling for the effects of both covariates. In conclusion, our findings highlight the important role of both biological maturation and training experience on youth basketball players' performance and development. We discuss the implications of these findings for research as well as for athletes, parents, coaches and clubs.

Patterns of physical performance spurts during adolescence: a cross-cultural study of Canadian, Brazilian and Portuguese boys.

BACKGROUND: Data relating physical performance to the timing of the adolescent growth spurt are limited. Aim: This study identifies: (i) age-at-peak height velocity (APHV), (ii) physical performance spurt patterns aligned to APHV; and (iii) cross-cultural and time patterns in Canadian, Brazilian and Portuguese boys. Subjects and methods: A total of 512 boys (131 Canadian, 250 Portuguese and 131 Brazilian), 8-17 years of age were followed serially using longitudinal data. APHV was identified and five physical performance measures velocities [trunk extension (TE), trunk flexion (TF), standing long jump (SLJ), curl-ups (CU) and handgrip strength (HG)] were aligned at 6-month intervals, 4 years around the attainment of PHV. Velocities were estimated using a non-smooth mathematical procedure. Results: APHV was 13.9 ± 1.0, 13.4 ± 1.6 and 13.0 ± 0.8 years for Canadian, Brazilian and Portuguese boys, respectively. Maximal velocity in SLJ was attained between 12 and 6 months prior to PHV. For HG, peaks were attained 12-24 months after PHV. Maximal velocity in TE occurred between 12 and 0 months prior to PHV, while CU peaked between PHV and 6 months after PHV. Conclusion: Patterns of spurts in physical performance have remained relatively the same and do not appear to be influenced by cross-cultural differences.

Are There Sensitive Periods for Skill Development in Male Adolescent Basketball Players?

PURPOSE: Although spurts in physical capacities during adolescence are well known, little is known about the existence of such spurts in sport-specific skill development, especially during the period of rapid growth in stature. Our aims were to examine the timing, intensity, and sequence of basketball-specific skill spurts aligned with biological (years from peak height velocity (PHV)) rather than chronological age. We then defined putative sensitive periods (windows of optimal development) for each skill aligned to the adolescent growth spurt. METHODS: Altogether, 160 adolescent male basketballers aged 11-15 yr were tested biannually over 3 consecutive years. The years from attainment of PHV was estimated, and six skill tests were aligned to each year from PHV in 3-month intervals. Skill velocities were estimated using a nonsmooth polynomial model. RESULTS: Maximal gains in slalom dribble occurred 12 months before PHV attainment (intensity, 0.18 m·s -1 ·yr -1 ), whereas in speed shot shooting (intensity, 9.91 pts·yr -1 ), passing (intensity, 19.13 pts·yr -1 ), and slalom sprint (intensity, 0.19 m·s -1 ·yr -1 ), these skill spurts were attained 6 months before PHV attainment. The mean gains in control dribble (intensity, 0.10 m·s -1 ·yr -1 ) and defensive movement (intensity, 0.12 m·s -1 ·yr -1 ) peaks coincided with attainment of PHV. We identified different sized windows for optimal development for each skill. CONCLUSIONS: Peak spurts in skill development, for most basketball skills, were attained at the same time as PHV. The multiple peaks observed within the defined windows of optimal development suggest that there is room for skill improvement even if gains might be greater earlier rather than later in practice. Our findings highlight the need to make coaches aware of where their players are relative to the attainment of PHV because different skills appear to develop differently relative to PHV. Such knowledge may help in designing more relevant training regimes that incorporate the athlete's current growth status so that skill development can be maximized.

The effects of resistance training on explosive strength indicators in adolescent basketball players.

The purpose of this study was to assess the effects of a lower- and upper-body 10-week in-season resistance training program on explosive strength development in young basketball players. Twenty-five adolescent male athletes, aged 14-15 years old, were randomly assigned to an experimental group (EG; n = 15) and a control group (CG; n = 10). The subjects were assessed at baseline and after training for squat jump (SJ), countermovement jump (CMJ), Abalakov test, drop jump, and seated medicine ball throw (MBT). The EG showed significant increases (p < 0.05) in all the variable scores. Conversely, the CG significantly decreased (p < 0.05) in SJ, CMJ, and Abalakov test scores and significantly increased in the results of MBT test (p < 0.05). The groups were similar on pretest, but significant differences (p < 0.05) occurred on posttest in all the variables. The results of this study show that a 10-week in-season resistance training program with moderate volume and intensity loads increased vertical jump and MBT performance in adolescent male basketball players. Coaches should know that such a short resistance training program specifically designed for young basketball players induce increased explosivity levels, which are essential to a better basketball performance, with no extra overload on adolescents' skeletal muscle development.

The effects of plyometric training followed by detraining and reduced training periods on explosive strength in adolescent male basketball players.

The aims of this study were to determine the effects of (a) plyometric training on explosive strength indicators in adolescent male basketball players and (b) detraining and reduced training on previously achieved explosive strength gains. Two groups were formed: an experimental and a control group. The former was submitted to a 10-week in-season plyometric training program, twice weekly, along with regular basketball practice. Simultaneously, the control group participated in regular basketball practice only. At the end of this period, the experimental group was subdivided into 2 groups: a reduced training group and a detraining group. All participants were assessed on squat jump, countermovement jump, Abalakov test, depth jump, mechanical power, and medicine ball throw at the beginning and at the end of the 10-week in-season plyometric training and on weeks 4, 8, 12, and 16 of the in-season detraining and reduced training periods. In the first phase of the study, the experimental group significantly increased all the assessed indicators (p < 0.05). In the following phase and in general all the groups maintained the previously achieved results. In conclusion, plyometric training showed positive effects on upper- and lower-body explosive strength in adolescent male basketball players. Moreover, we can state that both detraining and a reduced training program indistinctly contribute to maintenance of strength levels. These results highlight the unique power that basketball-specific training seems to have on the sustainability and maintenance of sport performance.

Muscular Strength Spurts in Adolescent Male Basketball Players: The INEX Study.

Although successful performance in basketball requires high levels of muscular strength during adolescence, its development is confounded by the effects of normal growth. We examine the timing, intensity and sequence of muscular strength according to biological age (years from peak height velocity (PHV)) and hypothesize that young basketball players attain their peak muscular strength spurts around PHV. A total of 160 adolescent male basketballers, aged 11-15 years, were followed bi-annually over 3 consecutive years. The years from attainment of PHV and peak weight velocity (PWV) were estimated and five muscular strength measures (sit-ups, handgrip, seated medicine ball throw, squat jump and countermovement jump) were aligned to years from PHV in 3-month intervals. Strength velocities were estimated using a non-smooth mathematical model. The mean ages at-PHV and at-PWV were 13.90 ± 1.40 years and 13.90 ± 1.79 years, respectively. Maximal velocity in sit-ups was attained 6 months prior to attainment of PHV (intensity = 10.69 repetitions·year-1), whereas maximal velocity in squat jump occurred 6 months after-PHV (intensity = 3.93 cm·year-1). Handgrip strength, seated medicine ball throw and countermovement jump maximal velocity peaked at-PHV (intensity = 8.47 kgf·year-1, intensity = 0.75 m·year-1, intensity = 5.59 cm·year-1, respectively). In general, maximal velocity spurts did not differ in their timing, with the velocities reaching a peak concurrent with PHV and PWV or within 6 months of its attainment. Basketball coaches, as well as strength and conditioning trainers, should consider individual differences in strength development and be aware of rapid periods of growth in stature when planning and designing muscular strength training regimes.

Modelling the dynamics of change in the technical skills of young basketball players: The INEX study.

Although technical skills are a prerequisite for success in basketball, little is known about how they develop over time. In this study, we model the trajectories of technical skill development in young basketball players and investigate the effects of training experience, training volume, body composition, maturity status, physical performance, and club characteristics on skill development. A total of 264 male basketballers from five age-cohorts (11 to 15 years of age) were followed consecutively over three years using a mixed-longitudinal design. Technical skills, training experience and volume, basic anthropometrics, body composition, biological maturation and physical performance were assessed bi-annually. A multilevel hierarchical linear model was used for trajectory analysis. Non-linear trends (p < 0.01) were observed in speed shot shooting, control dribble, defensive movement, slalom sprint, and slalom dribble. Being more experienced and physically fitter had a significant (p < 0.05) positive effect on technical skill development; greater fat-free mass negatively affected skills demanding quick running and rapid changes of direction with or without the ball (p < 0.05). Training volume and biological age did not explain differences in technical skill development (p > 0.05). Moreover, belonging to different clubs had no significant influence on the technical skills trajectories of players. Our findings highlight the important role that individual differences play, over and beyond club structure, in developing skills. Findings improve our understanding on how technical skills develop during adolescence through training, growth, and biological maturation.

Tracking Technical Skill Development in Young Basketball Players: The INEX Study.

This study investigated developmental stability, or tracking, in the development of technical skills in youth male basketball players and retrospectively profiled stable and unstable tracking patterns over time. A total of 97 basketball players were tracked bi-annually over 3 consecutive years. Players were divided into two age-categories according to their age at baseline: under-12; and under-14. Technical skills were assessed using the American Alliance for Health, Physical Education, Recreation and Dance test battery. Anthropometric, body composition, biological maturation and physical performance data were collected. Cohen's kappa (κ) was used to estimate tracking. With the exception of defensive movement in the under-12 age-category, tracking was low in all skill tests for both under-12 (0.22 ≤ κ ≤ 0.33) and -14 (0.20 ≤ κ ≤ 0.26) groupings. The overall technical skill showed moderate tracking for under-12 players (κ = 0.47) and low tracking for under-14 players (κ = 0.26). At baseline, players who were consistently more skilled or became more skillful (in the under-12 age-category) over time had a better growth-motor performance profile and most of them were selected to be members of regional teams. In conclusion, tracking of individual skill trajectories was low-to-moderate. Moreover, a better growth-motor performance profile seems crucial to maintain high levels of skill performance over time. It is recommended that basketball coaches track the developmental trajectories of their players to better understand the erratic nature of skill development and help design more effective practice regimes.

Effects of reduced training and detraining on upper and lower body explosive strength in adolescent male basketball players.

The purpose of this study was to assess and compare the effects of detraining and of a reduced training program on upper- and lower-body explosive strength in adolescent male basketball players. To study this, 15 subjects, aged 14 to 15 years old, were randomly assigned to 1 of the 2 following groups: reduced training (RT; n = 8) and detraining (DTR; n = 7). The participants were assessed on squat jump (SJ), countermovement jump (CMJ), Abalakov test (ABA), depth jump (DJ), mechanical power (MP), and medicine ball throw (MBT) after a 10-week in-season complex training program (T0) and at the end of 4 (T4), 8 (T8), 12 (T12), and 16 (T16) weeks of detraining and of the reduced training periods. Both groups showed maintenance of explosive strength values and statistical similarity between them whatever the moment of evaluation. In conclusion, 16 weeks of detraining or of reduced training allow for the maintenance of the gains previously achieved by the application of a 10-week in-season complex training program. However, the lack of differences between detraining and reduced training leads to the conclusion that regular basketball practice can sustain by itself the previously achieved explosive strength gains, considering its mainly explosive characteristics.

How Does Biological Maturation and Training Experience Impact the Physical and Technical Performance of 11-14-Year-Old Male Basketball Players?

This study (1) investigated the effects of age, maturity status, anthropometrics, and years of training on 11-14-year-old male basketball players' physical performance and technical skills development, and (2) estimated the contribution of maturity status and training years on players' physical and technical performances. The sample consisted of 150 participants, average age 13.3 ± 0.7 years, grouped by early, average, and late maturation. Biological maturation, anthropometry, and training data were collected using standard procedures. Measures of physical performance assessed included: aerobic fitness, abdominal muscular strength and endurance, static strength, lower body explosive power, upper body explosive power, speed, and agility and body control. Basketball-specific technical skills were also recorded. Analysis of variance (ANOVA) and analysis of covariance (ANCOVA) were used to compare group differences. Results indicated that early maturers were taller, heavier, and had greater strength, power, speed, and agility (p < 0.05). When controlling for age, height, and body mass, early maturers remained stronger, quicker, and more agile (p < 0.05). They were also more skillful in the speed shot shooting test (p < 0.05). Apart from tests of aerobic fitness, abdominal muscular strength and endurance, and lower body explosive power, maturity status was the primary contributor to the variance in the physical performance tests. Years of training was the primary contributor to the variance in the technical skills tests. Whilst physical performance was dependent on maturity status, technical skills were influenced by years of training. Since both biological maturation and years of training play an important role in basketball performance, we recommend that coaches consider the effects of these two confounders when recruiting and selecting youth basketballers.

Effects of complex training on explosive strength in adolescent male basketball players.

The purpose of this study was to evaluate the effects of a complex training program, a combined practice of weight training and plyometrics, on explosive strength development of young basketball players. Twenty-five young male athletes, aged 14-15 years old, were assessed using squat jump (SJ), countermovement jump (CMJ), Abalakov test (ABA), depth jump (DJ), mechanical power (MP), and medicine ball throw (MBT), before and after a 10-week in-season training program. Both the control group (CG; n = 10) and the experimental group (EG; n = 15) kept up their regular sports practice; additionally, the EG performed 2 sessions per week of a complex training program. The EG significantly improved in the SJ, CMJ, ABA, and MBT values (p < 0.05). The CG significantly decreased the values (p < 0.05) of CMJ, ABA, and MP, while significantly increasing the MBT values (p < 0.05). Our results support the use of complex training to improve the upper and lower body explosivity levels in young basketball players. In conclusion, this study showed that more strength conditioning is needed during the sport practice season. Furthermore, we also conclude that complex training is a useful working tool for coaches, innovative in this strength-training domain, equally contributing to a better time-efficient training.

Efeitos do treino e do destreino específicos na força explosiva: um estudo em jovens basquetebolistas do sexo masculino / Effects of specific training and detraining in explosive strength: a study on yong male basketball players

Os objetivos do presente estudo foram os seguintes: a) identificar os efeitos do treino pliométrico nos indicadores da força explosiva (velocidade, agilidade, salto a partir de uma posiçäoestática, salto com contra-movimento e potência mecânica média dos membros inferiores) de jovens basquetebolistas; e b) perceber os efeitos do destreino específico e da aplicaçäo de um treino pliométrico reduzido, nos ganhos anteriormente obtidos. A amostra foi constituída por 19 jovens basquetebolistas do sexo masculino (idade 14 e 15 anos). A estrutura adaptada para a consecuçäo do presente estudo acentuou em duas partes fundamentais. Numa primeira parte, o s indivíduos foram sujeitos a um programa de treino pliométrico (saltos no lugar, saltos com deslocamento, saltos em profundidade e saltos com carga adicional), com a duraçäo de oito semanas e uma freqüência de três vezes por semana. No final deste período, o test-t de medidas repetidas revelou incrementos estaisticamente significativos em todos os indicadores de força explosiva (p<0,05). Na segunda parte, imediatamente após as oito semanas de treino, os sujeitos foram aleatoriamente distribuídos por dois grupos: O primeiro (G1,n=10), respeitou um período de treino específico de quatro semanas mantendo, contudo, os treinos regulares de basquetebol; os indivíduos restantes (G2,n=9) cumpriram um programa de treino pliométrico reduzido em simultâneo com os treinos regulares de basquetebol. A estrutura de treino adaptada foi idêntica à fase inicial, com os mesmos níveis de intensidade, mas com uma reduçäo na freqüência (uma vez por semana) e no volume. No final deste período, o test-t de medidas repetidas permitiu verificar: no G1, mehorias estatisticamente significativas na velocidade, no salto a partir de uma posiçäo estática e no salto com contra-movimento (p<0,05), mantendo praticamente inalterados os valores referentes à agilidade e à potência mecânica média; no G2, incrementos estatisticamente significativos para a velocidade e agilidade (p<0,05), tendo as restantes variáveis mantido os níveis anteriormente atingidos. Posteriormente, o test-t de medidas independentes (G1 vs. G2), revelou a semelhança entre os grupos relativamente às variáveis em estudo...