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A soccer match induce changes in physiological stress biomarkers as testosterone (T), cortisol (C), and testosterone:cortisol (T:C) ration. Hydration state may also modulate these hormones, and therefore may alter the anabolic/catabolic balance in response to soccer match. The role of hydration status before the match in this biomarkers has not yet been reported. The aim of this study was to compare the salivary T, C, and the T:C ratio responses after two friendly matches in well-hydrated and mild-dehydrated (MD) elite young male soccer player. Seventeen players (age, 16.8 ± 0.4 years; VO2max 57.2 ± 3.6 ml/kg−1/min−1) were divided into two teams. Before the matches the athletes were assessed for hydration level by the urine specific gravity method and divided for the analysis into well-hydrated (WH; n = 9; USG < 1.010 g/mL−1) and mild-dehydrated (MD; n = 8; USG 1.010 to 1.020 g/mL−1) groups. Hormones were collected before and after each match by saliva samples. The mean (HRmean) and maximal (HRmax) heart rate were measured throughout the matches. A two-way ANOVA was used to compare T, C, and T:C between and within groups. Similar HRmean (WH, 83.1 ± 4.7%; MD, 87.0 ± 4.1; p = 0.12) and HRmax (WH, 93.2 ± 4.4%; MD, 94.7 ± 3.7%; p = 0.52) were found for both groups during the matches. No differences were found before the matches in the T (p = 0.38), C (p = 66), nor T:C (p = 0.38) between groups. No changes within groups were found after matches in neither group for T (WH, p = 0.20; MD, p = 0.36), and T:C (WH, p = 0.94; MD, p = 0.63). Regarding the C, only the MD group showed increases (28%) after the matches (MD, p = 0.03; WH, p = 0.13). In conclusion MD group exacerbate the C response to friendly matches in elite young male soccer players, suggesting that dehydration before match may be an added stress to be considered.

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SUMMARYEucalyptus nitens is an important commercial fast growing species planted mainly in Chile and Australia (Tasmania). In Chile there are not previously published studies quantifying leaf area in adult forest plantations of E. nitens. This study presents the effect of pruning and thinning intensities, applied at age 6 in a E. nitens stand, and on the amount of leaf area sustained at 15 years old. A factorial experiment considering pruning (0 m, 3.5 m and 7 m height) and stocking (1,100, 800 and 400 trees ha -1 ) was established in 1989 near Los Álamos town in central Chile. Using the average tree method, 27 trees were sampled destructively for biomass and leaf area assessments. Projected leaf area, leaf area index, and specific leaf area were estimated for each sampled tree. The results indicate that projected leaf area and leaf area index reached a maximum of 64.7 m 2 tree -1 at 400 trees ha -1 stocking and 3.48 m 2 m -2 at 800 trees ha -1 stocking respectively. Specific leaf area was higher (43.2 cm 2 g -1 ) at higher stocking (1,100 trees ha -1 ). For all treatments projected leaf area and leaf area index were higher in the central section of the crown. Allometric relationships were obtained using diameter at the base of the live crown and stump diameter. The information presented in this study allows giving a more functional explanation of the horizontal and vertical behavior of the leaf area, at different stocking.Key words: Eucalyptus nitens, leaf area, pruning, thinning. RESUMENEucalyptus nitens es una especie de rápido crecimiento plantada principalmente en Chile y Australia (Tasmania). En Chile, no hay estudios publicados de área foliar en bosques adultos de E. nitens. Se investigó el efecto de la poda y el raleo en el área foliar de E. nitens. Los datos utilizados provienen de una plantación de 15 años de edad, luego de nueve años de establecido el ensayo. El estudio fue realizado en una plantación efectuada el año 1989, cercana a la localidad de Los Álamos, zona central de Chile, según un arreglo factorial de dos factores: intensidad de raleo y severidad de poda. Utilizando el método del árbol medio, se seleccionaron 27 árboles que posteriormente fueron volteados. Con las mediciones realizadas se obtuvo el área foliar proyectada, índice de área foliar y área foliar específica. El análisis de varianza evidenció un efecto significativo del raleo sobre el área foliar. El área foliar proyectada e índice de área foliar es máxima en los tratamientos de densidad 400 árboles ha -1 (64,7 m 2 árbol -1 ) y en tratamientos de densidad 800 árboles ha -1 (3,48 m 2 m -2 ), respectivamente. El área foliar específica es mayor en tratamientos de densidad 1.100 árboles ha -1 (43,2 cm 2 g -1 ). El área foliar proyectada e índice de área foliar se concentran en la sección central de la copa. Los modelos alométricos determinados utilizan como variable predictora el diámetro en la base de la copa viva y el diámetro de tocón. La información presentada en el estudio permite dar una explicación más funcional del comportami...

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