Biological maturity status and motor performance in fourteen-year-old basketball players / Estado de madurez biológica y desempeño motriz en jugadores de baloncesto de catorce años de edad

The aims of this study were to detect biological maturity and certain athletic skills in boys aged 14 participating in competitive basketball, and to compare certain athletic skills of participants according to their biological maturity status. The participants were most talented Serbian basketball players (n= 49) who were divided into three groups according to their maturity status: early (n= 14), average (n= 24) and late maturing (n= 11). Biological maturity status of participants was assessed by technique developed by Mirwald et al. (2002). Nine tests of basic athletic skills: vertical jump, medicine ball throwing, run at 20, 30 and 50 m, agility t-test, zigzag agility drill, agility run 4x15 m, the line drill, as well as four basketball skills field tests (speed spot shooting, passing, control dribble and defensive movement) were applied. The results of this study showed that the three groups of subjects differed in applied variables (p <0.05). Average maturers achieved the best results in almost all variables, while late maturers achieved the worst results. Early maturers achieved the best results only in one variable - medicine ball throwing. Only harmonized chronological and biological age, i.e. chronological and biological growth and development, enable the best demonstration of motor abilities based on morphological characteristics.

Los objetivos fueron detectar la madurez biológica y ciertas habilidades atléticas en los varones mayores de 14 años que participan en el baloncesto competitivo, y compararlas en función de su estado de madurez biológica. La muestra se conformó con jugadores de baloncesto serbios de mayor talento (n= 49) que fueron divididos en tres grupos de acuerdo a su estado de madurez: temprana (n= 14), promedio (n= 24) y tardía (n= 11). El estado de madurez biológica de los participantes se evaluó mediante la técnica desarrollada por Mirwald et al. (2002). Se aplicaron nueve pruebas de habilidades atléticas básicas: salto vertical, lanzamiento de balón medicinal, carrera de 20, 30 y 50 m, prueba t de agilidad, agilidad en zig-zag, carrera en 4x15 m, línea de perforación, así como pruebas de campo de baloncesto de cuatro habilidades (velocidad de disparos punto, de paso, control de regate y movimiento defensivo). Los resultados de este estudio mostraron que los tres grupos de sujetos diferían en variables aplicadas (p <0,05). Los jugadores de maduración media obtuvieron los mejores resultados en casi todas las variables, mientras que los jugadores de maduración tardía alcanzaron los peores resultados. Los jugadores de maduración temprana lograron el mejor resultado en sólo una variable ­ el lanzamiento de balón medicinal. Solamente el desarrollo cronológico armónico y la edad biológica, es decir, el crecimiento y el desarrollo cronológico y biológico, permiten la mejor demostración de las habilidades motoras basadas en características morfológicas.

Speed and agility of 12- and 14-year-old elite male basketball players.

The aims of this study were (a) to identify and compare the speed and agility of 12- and 14-year-old elite male basketball players and (b) to investigate relations between speed and agility for both age groups of basketball players, to help coaches to improve their work. Sixty-four players aged 12 (M = 11.98 years, SD = 0.311) and 54 players aged 14 (M = 14.092 years, SD = 0.275) were tested. Three agility tests: agility t-test, zigzag agility drill, and agility run 4 × 15 m and 3 speed tests: 20-m run, 30-m run, and 50-m run were applied. Fourteen-year-old players achieved significantly better results in all speed and agility tests compared with 12-year-old players. The correlation coefficient (r = 0.81, p = 0.001) showed that 12-year-old players have the same ability in the 30- and 50-m runs. The other correlation coefficient (r = 0.59, p = 0.001) indicated that 20- and 30-m runs had inherently different qualities. The correlation coefficients between agility tests were <0.71, and therefore, each test in this group represents a specific task. In 14-year-old players, the correlation coefficients between the speed test results were <0.71. In contrast, the correlation coefficients between the agility tests were >0.71, which means that all the 3 tests represent the same quality. During the speed training of 12-year-old players, it is advisable to focus on shorter running distances, up to 30 m. During the agility training of the same players, it is useful to apply exercises with various complexities. In speed training of the 14-year-old players, the 30- and 50-m runs should be applied, and agility training should include more specific basketball movements and activities.

The influence of training status on oxidative stress in young male handball players.

Although exercise-induced oxidative stress receives considerable scientific attention, there is still little information available regarding exercise-induced adaptations of the antioxidant defence system in adolescent and child athletes. The aim of our study was to establish the effects of long-term exercise training on the redox state of adolescents, and to find correlations between elements of redox homeostasis and aerobic power. Thirty-three handball players and 14 non-athletes, 16-19-years old, were subjected to blood sampling to measure levels of nitric oxide (NO; estimated through nitrites (NO2⁻), superoxide anion radical (O2⁻), hydrogen peroxide (H2O2), lipid peroxidation (estimated through TBARS), superoxide dismutase (SOD) and catalase (CAT). Subjects were also subjected to maximal progressive exercise test to estimate their maximal oxygen consumption (VO2max). Athletes had significantly (P < 0.05) higher SOD activity and lower CAT activity compared with non-athletes (SOD: 2175.52 ± 362.07 compared with 1172.16 ± 747.40 U/g of hemoglobin x 10³, and CAT: 2.19 ± 0.31 compared with 3.08 ± 0.47 U/g of hemoglobin x 10³). These differences were the most obvious when comparing non-athletes and athletes with poor/average aerobic power. H2O2 and TBARS levels differed among subjects with poor, average or good aerobic power (P < 0.01, and P < 0.05, respectively). Sports engagement and aerobic capacity are important factors in inducing changes in redox status.