RESUMO
The aims of this study were: i) to verify whether player internal load (PIL) monitored via heart rate (HR) varies with game-time and playing position; ii) whether intermittent running capacity (IRC) is related to the maintenance of within-match PIL in elite youth (U-15) soccer players. Method: Twenty-one elite soccer players (14±0.5 yrs, 172±7 cm, 63±6 kg) had their heart rate monitored (beats/min) in five matches and were tested twice for IRC (Yo-YoIR2, distance [m]) over a seven-week competitive season. Percentage of maximal heart rate (%HRmax) and time spent (TS%) in five zones (Z1[<70%]; Z2[71-85%]; Z3[86-90%]; Z4[91-95%] and Z5[>96%]) were our PIL indexes. Data from three complete games in the same position of each player were analyzed and matches halves, time intervals (T1 to T6), and playing positions (fullbacks, central defenders and forwards [N=5 each], midfielders [N=6]) were compared, and the relationship between IRC and within-match PIL was determined. Results: PIL was higher in 1st (86±3%) than in the 2nd half (84±4%; p<.001). The 2nd half had more TS% in Z1 and Z2 (p<.05). PIL in T4 was the lowest (p<.01), and in T6, it was lower than T1 and T2 (p<.01). Fullbacks and midfielders showed higher PIL and higher TS% in Z4 (p<.05) than the other positional roles. The average IRC correlated with PIL in T6 (r=.56, p<.01) only. Conclusion: In conclusion, the internal load in elite youth (U-15) soccer players varies with game-time and playing position; and their IRC is related to the maintenance of within-match PIL.(AU)
Assuntos
Humanos , Masculino , Adolescente , Futebol/fisiologia , Desempenho Atlético/fisiologia , Frequência Cardíaca/fisiologia , Atletas , Esportes JuvenisRESUMO
The aim of this research was the estimation of anthropometric characteristics of elite male basketball players from four Bosnian first league teams, as well as the identification of possible differences between players who play in different positions in the teams. Fifty-five, healthy players (age: 19.09±3.13 years; body height: 189.13±8.30 cm; body mass: 83.42±12.48 kg) were divided into three different subsamples according to their positional role (twenty two guards, nineteen forwards and fourteen centers). Twenty morphological variables were measured and afterwards one (BMI) was calculated. For all anthropometric characteristics, descriptive parameters (mean, standard deviation and range) were calculated. In order to determine the possible differences between the players that play in different positions in the teams the analysis of variance (ANOVA) with Bonferoni post-hoc test for multiple comparisons was used. The results obtained show that there are significant differences between the different groups of players in sixteen out of twenty-one measured variables. Centers (big players) are dominantly heavier, taller, with longer and wider skeletons dimensionality as well as with bigger body circumferences compared to forwards and guards. Forwards are significantly heavier and taller with longer leg and arm lengths compared to guards. There are no significant differences between the groups in terms of body fat percentage, fat free percentage, body mass index and biepicondylar breadth of the femur and humerus. Generally, the values of the measured variables rise from guards to centers, except for body fat percentage and skinfolds. The obtained information can help coaches to indirectly evaluate fitness levels of the players and to design training and nutritional programs for basketball players.
El objetivo fue estimar las características antropométricas de los jugadores de baloncesto de elite en cuatro equipos bosnios de primera liga. Además, fueron identificadas las posibles diferencias entre los jugadores que ocupan distintas posiciones en los equipos. Fueron evaluados 55 jugadores sanos (edad: 19,09±3,13 años; altura del cuerpo: 189,13±8,30 cm; masa corporal: 83,42±12,48 kg) se dividieron en tres submuestras diferentes de acuerdo a su rol posicional (22 guardias, 19 aleros y 14 centros). Se midieron 20 variables morfológicas y luego se calculó el IMC y otros parámetros descriptivos (media, desviación estándar y rango) para todas las características antropométricas. Para determinar las posibles diferencias entre los jugadores que juegan en distintas posiciones se utilizó el análisis de varianza (ANOVA) con la prueba post-hoc de Bonferoni de comparaciones múltiples. Existen diferencias significativas en dieciséis de las veintiuna variables medidas entre los diversos grupos de jugadores. Los jugadores de centro son predominantemente más pesados y más altos, con una dimensión de esqueleto más amplia, como también una circunferencia corporal mayor, en comparación con jugadores en posiciones forwards y guardias. Los delanteros son significativamente más pesados y más altos con un largo mayor de piernas y brazos en comparación con los guardias. No existen diferencias significativas entre los grupos en términos de porcentaje de grasa corporal, porcentaje de grasa, IMC y la amplitud bicondilea del fémur y húmero. Con excepción del porcentaje de grasa corporal y pliegues cutáneos, los valores de las variables medidas aumentan desde los jugadores guardias a los jugadores de centro. Esta información puede ayudar a los entrenadores a evaluar los niveles de aptitud de los jugadores, como también en la planificación de capacitación y programas de nutrición para los jugadores de baloncesto.