Relationship between the cardiovascular capacity and repeated sprints ability in high-standard soccer referees

Los objetivos de este estudio fueron por un lado, describir el rendimiento en una prueba de rendimiento cardiovascular realizada en laboratorio y en otra de esprints repetidos (RSA) en árbitros de fútbol de alto nivel, y por otro lado, analizar la asociación entre los resultados obtenidos en ambas pruebas. Doce árbitros de fútbol de alto nivel (Divisiones 1ª, 2ª y 2ª B, 28,8±5,1 años, 73,2±6,6 kg, 1,8±0,1 m 22,82±1,38 kg·m-2) participaron en el estudio. Los árbitros obtuvieron un consumo máximo de oxígeno (VO2max) de 59,50±4,56ml·kg-1·min-1. El tiempo medio de los esprints repetidos (RSAMedia) en 15 y 30 m fue de 2,54±0,09 s y 4,43±0,14 s, respectivamente, tardando 15,26±0,53 s y 26,60±0,82 s en completar los seis esprints (RSATotal). Los índices de fatiga en 15 y 30 m fueron de 2,25±1,05% y 3,33±1,59% (RSASdec) y de 3,45±2,92% y 6,31±4,63% (RSACambio). Se obtuvieron asociaciones positivas entre distintas variables cardiovasculares y de tiempo en RSA. Por el contrario, el consumo de oxígeno en las intensidades de umbral ventilarorio 1 (VT1) y umbral ventilatorio 2 (VT2) correlacionó negativamente con el índice de fatiga RSASdec. Una mayor capacidad cardiovascular en árbitros de fútbol, a pesar de poder producir un efecto negativo sobre el tiempo empleado en el RSA, puede minimizar la fatiga durante los esprints repetidos

Relación entre la capacidad cardiovascular y la capacidad de esprints repetidos en árbitros de fútbol de alto nivel

The aims of this study were on the one hand, to describe the performance in a laboratory cardiovascular test and in a repeated sprint ability (RSA) test, and on the other, to analyze the association between the results obtained in both test. Twelve high-standard soccer referees (1st, 2ndy 2ndB Divisions, 28,8 ± 5,1 years, 73,2 ± 6,6 kg, 1,8 ± 0,1 m and 22,82 ± 1,38 kg·m-2) participated in this study. Soccer referees obtained 59,50 ± 4,56 ml·kg-1·min-1of maximum oxygen consumption (VO2max). Mean time (RSAMedia) spent to perform the repeated sprints in 15 and 30 m distances was 2,54 ± 0,09 s and 4,43 ± 0,14 s, and total time (RSATotal) was 15,26 ± 0,53 s and 26,60 ± 0,82 s, respectively. Fatigue indexes (RSASdecand RSACambio) in 15 and 30 m distances were 2,25 ± 1,05% and 3,33 ± 1,59%, and 3,45 ± 2,92% y 6,31 ± 4,63%, respectively. Positive associations were found between cardiovascular variables and RSA time variables. On the other side, oxygen consumption at ventilatory threshold 1 (VT1) and ventilatory threshold 1 (VT2) and fatigue index (RSASdec) correlated negatively. Despite a higher cardiovascular capacity in soccer referees may generate a negative effect on the time spent in RSA, it also minimize the fatigue during repeated sprints. Physical trainers should focus the training of soccer referees on the cardiovascular capacity and they should implement acceleration specific training.  Los objetivos de este estudio fueron por un lado, describir el rendimiento en una prueba de rendimiento cardiovascular realizada en laboratorio y en otra de esprints repetidos (RSA) en árbitros de fútbol de alto nivel, y por otro lado, analizar la asociación entre los resultados obtenidos en ambas pruebas. Doce árbitros de fútbol de alto nivel (Divisiones 1ª, 2ª y 2ª B, 28,8±5,1 años, 73,2±6,6 kg, 1,8±0,1 m 22,82±1,38 kg·m-2) participaron en el estudio. Los árbitros obtuvieron un consumo máximo de oxígeno (VO2max) de 59,50±4,56ml·kg-1·min-1. El tiempo medio de los esprints repetidos (RSAMedia) en 15 y 30 m fue de 2,54±0,09 s y 4,43±0,14 s, respectivamente, tardando 15,26±0,53 s y 26,60±0,82 s en completar los seis esprints (RSATotal). Los índices de fatiga en 15 y 30 m fueron de 2,25±1,05% y 3,33±1,59% (RSASdec) y de 3,45±2,92% y 6,31±4,63% (RSACambio).Se obtuvieron asociaciones positivas entre distintas variables cardiovasculares y de tiempo en RSA. Por el contrario, el consumo de oxígeno en las intensidades de umbral ventilarorio 1 (VT1) y  umbral ventilatorio 2 (VT2) correlacionó negativamente con el índice de fatiga RSASdec.Una mayor capacidad cardiovascular en árbitros de fútbol, a pesar de poder producir un efecto negativo sobre el tiempo empleado en el RSA, puede minimizar la fatiga durante los esprints repetidos

Validation of an Inductively Coupled Plasma-Optical Emission Spectrometry Method for the Determination of Major Elements in Farmed Rainbow Trout (Oncorhynchus mykiss)

An inductively coupled plasma−optical emission spectrometry method was optimized and validated for the determination of major elements (Ca, K, Mg, Na and P) in cultivated freshwater fish (rainbow trout Oncorhynchus mykiss). The method was validated by analysis of a Certified Reference Material, consisting in a frozen tissue homogenate from lake trout (Salvelinus namaycush namaycush). The linearity of this method was very good, as evidenced by the coefficients of correlation (r) for calibration graphs that were higher than 0.9999 in all cases and by linearity test (response factor <5% and relative calibration graph slope <2%). Accuracy, expressed as relative recovery (%) in comparison with certified concentration ranged from 100 to 109%, and precision, expressed as residual standard deviation (%) ranged from 1.2 to 6.5% (repeatability) and from 1.0 to 9.6% (reproducibility). The limit of quantification ranged from 4 ng/mL (Ca and Mg) to 203 ng/mL (P). The optimized method was applied to major element determination in skin and muscle samples from rainbow trout fillets

Effect of inclusion level of linseed on the nutrient utilisation of diets for growing broiler chickens

1. Diets containing linseed at inclusions of 0, 80, 120 and 160 g/kg were evaluated for digestibility of nutrients and AMEn content with male broiler chickens. 2. Increasing the concentration of linseed decreased the retention of nitrogen and the digestibility of amino acids, crude fat and fatty acids of diets. 3. Dietary AMEn (MJ/kg) was also affected by the rate of inclusion of linseed, values decreasing from 14.39 to 12.49. 4. In general, a linear regression model explained the relationship between dietary linseed content and nutritive parameters. However, the quadratic response found for the digestibility of several amino acids and fatty acids indicated a non-additive change in their digestibility. 5. Viscosity of jejunal digesta was markedly increased by each increment of linseed in the diets. This is attributable to the presence of mucilage in linseed and it might explain many of the results obtained in this study. © 2001 British Poultry Science Ltd.Peer Reviewe

Yields and chemical composition of different parts of the common vetch at flowering and at two seed filling stages

In annual forage legumes such as the common vetch (Vicia sativa L.), in which the pods represent a substantial proportion of the total biomass, the optimum harvesting stage may not adjust to the classical model of decreasing nutritive value after flowering. The effect of harvest time on the yield of the main chemical components of common vetch was evaluated under field conditions typical of the Castilian Plain (Mediterranean continental-type climate under rain-fed conditions). Over two growing seasons (1996-1997 and 1997-1998), plants were harvested at flowering and at two stages during seed filling (characterized by a progressively higher dry matter content of the seed; 280 and 380 g kg-1 respectively). The results show that the greater quality and quantity of the pods offsets the decrease in quality occasioned by the aging of the vegetative plant parts (stems plus leaves). Crude protein yields were not affected by delaying the harvest-time. Starch yields were higher when the plant was harvested during seed-filling. Sugar yields increased between flowering and seed filling in the first growing season but decreased in the second. Yields of structural components such as neutral-detergent fibre, acid-detergent fibre and acid-detergent cellulose, followed a pattern similar to that of crude protein. There therefore appears to be a flexible harvest period ranging from flowering until the beginning of seed filling (seeds with 380 g dry matter kg-1), which may be advantageous when trying to select optimum haymaking conditionsEn leguminosas forrajeras anuales como la veza común (Vicia sativa L.), en las que la legumbre representa una proporción considerable de la biomasa total, el momento óptimo de corte puede no ajustarse al modelo clásico de disminución del valor nutritivo después de la floración. En este trabajo se evaluó el efecto del momento de recolección de la veza común sobre el rendimiento de los principales constituyentes químicos en condiciones de secano típicas de la Meseta Castellana. Las plantas se cosecharon durante dos años consecutivos (1996-1997 y 1997-1998), en floración y en dos estados de madurez de la legumbre (materia seca de la semilla 280 y 380 g kg-1, respectivamente). Los resultados mostraron que, al avanzar la madurez, la mayor calidad y cantidad de la legumbre contrarresta la disminución de la calidad de las partes vegetativas de la planta. Los rendimientos de proteína bruta no se vieron afectados por un retraso en la fecha de recolección. Los de almidón, sin embargo, fueron mayores al estado de legumbre madura, y los de azúcares aumentaron desde la floración al estado de legumbre en el primer año, mientras que disminuyeron en el segundo año. Los rendimientos de constituyentes estructurales (fibra neutro-detergente, fibra ácido-detergente y celulosa ácido-detergente) siguieron una tendencia similar a los de la proteína bruta. Se concluye que existe un margen de maniobra entre la floración y las primeras fases de formación de la semilla (semilla con 380 g de materia seca kg-1) que permite elegir las mejores condiciones de henificació

Effects of removal of mucilage and enzyme or sepiolite supplement on the nutrient digestibility and metabolyzable energy of a diet containing linseed in broiler chickens

Two experiments were conducted with broiler chickens from 22 to 28 days of age. In Experiment 1, the effect of adding enzyme preparations to a maize, soyabean meal and linseed (125 g kg-1) basal diet was evaluated. Commercial enzyme complexes (Energex® CT, Luctazyme® aviar and Pectinase Lucta) with high xylanase and pectinase activities were used. The results showed that responses to enzymes in terms of digestibility of protein, amino acids, fat and major fatty acids as well as dietary AME value (AMEn) were not significant. Digesta viscosity value at the jejunal level was not affected by enzyme treatment. In Experiment 2, the effects of substituting demucilaged-linseed for linseed in the basal diet and addition of sepiolite to a diet containing linseed were evaluated. Removal of mucilage was achieved by extracting the seed with hot water (80°C) for 2 h. The substitution of demucilaged-linseed for linseed significantly improved the digestibility of fat and major fatty acids as well as AMEn. Moreover, digesta viscosity was markedly reduced (29.6 vs. 4.9 cP). Addition of sepiolite to the diet containing linseed had no influence on the nutrient utilization and on intestinal digesta viscosity. © 2002 Elsevier Science B.V. All rights reserved.Peer Reviewe

Effect of dietary high-oleic acid sunflower seed, palm oil and vitamin E supplementation on broiler performance, fatty acid composition and oxidation susceptibility of meat

1. A study was conducted to evaluate the effect of inclusion of two fat sources: high-oleic acid sunflower seed (HOASS; 0, 50, 100, 150 and 200 g/kg diet) and palm oil (PO), and dietary supplementation of vitamin E (α-tocopheryl acetate, 200 mg/kg diet) on performance, fatty acid composition and susceptibility to oxidation of white and dark chicken meat during refrigerated storage. Female chicks (3 to 6 weeks) were given one of 5 diets containing 90 g/kg of added fat with increasing monounsaturated fatty acid (MUFA) content, adjusted by progressively replacing PO by HOASS.2. Body weight gain and gain:food ratio of birds were depressed in diets containing the highest proportions of HOASS (150 and 200 g/kg). Relative abdominal fat was reduced in birds fed diets including HOASS, except in the diet containing 100 g HOASS/kg. The inclusion of α-tocopheryl acetate improved body weight gain and gain:food ratio.3. According to the fatty acid profile of the diets, saturated and polyunsaturated fatty acid (SFA and PUFA, respectively) contents were significantly reduced and MUFA content was significantly increased in white and dark chicken meats when the saturated oil, PO, was replaced progressively by HOASS in the diet. The inclusion of α-tocopheryl acetate increased PUFA content in both meats.4. After 4 and 7 d of refrigerated storage, white and dark meat samples obtained from birds fed on diets containing HOASS had significantly lower thiobarbituric acid reacting substance (TBARS) values than those derived from the PO diet. The addition of α-tocopheryl acetate significantly reduced the lipid oxidation in white and dark meat.5. Overall, the results showed that increasing MUFA content of chicken meat by replacing dietary PO with HOASS (up to 100 g/kg) did not adversely affect broiler performance and reduced the susceptibility of meat to oxidation during refrigerated storage. Dietary α-tocopherol supplementation improved chicken performance and was effective in protecting lipid meat from oxidation.This study was supported by a grant from CICYT (Comisión Interministerial de Ciencia y Tecnología) of Spain as a part of Project AGL2001-1116.Peer reviewe

Interaction of dietary high-oleic-acid sunflower hulls and different fat sources in broiler chickens

The effect of dietary fat sources (high-oleic-acid sunflower seeds, HOASS; palm oil, PO; and high-oleic-acid sunflower oil, HOASO) and high-oleic-acid sunflower hulls (HOAS hulls; 40 g/kg of diet) on performance, digestive organ size, fat digestibility, and fatty acid profile in abdominal fat and blood serum parameters was evaluated in chickens (from 1 to 21 d of age). Bird performance and digestive organ size were not affected by either dietary fat source or sunflower hull supplementation. Fat digestibility in birds fed diets enriched (HOASS and HOASO) in monounsaturated fatty acids (MUFA) was increased compared with those fed the PO diet. The addition of sunflower hulls did not modify fat digestibility. The fatty acids pattern of abdominal fat reflected the dietary fat profile. The greatest concentrations of C16:0 and C18:0 were found in birds fed PO diets. The C18:1n-9 content was increased in birds that received HOASS and HOASO diets compared with those fed PO diets. The greatest content of C18:2n-6 was observed in birds fed HOASS diets. The ratio of polyunsaturated fatty acid (PUFA) to MUFA was significantly increased in birds fed PO diets compared with those fed HOASS or HOASO diets. The addition of sunflower hulls to the diets resulted in a decrease of C18:2n-6 and PUFA concentrations and PUFA:MUFA ratio in abdominal fat. Dietary fat sources and sunflower hulls modify blood triglycerides and serum lipoproteins. A decrease in triglyceride concentrations was observed in birds fed HOASS diets compared with those fed PO and HOASO diets. The greatest concentrations of serum high density, very low density (VLDL), and low density lipoproteins were found in birds receiving HOASO, PO, and HOASS diets, respectively. The addition of sunflower hulls to the diets caused an increase of serum triglycerides and VLDL concentrations. The MUFA-enriched diets had lower triglyceride and VLDL concentrations than did diets rich in saturated fatty acids. However, the sunflower hull addition had the opposite effect. © 2009 Poultry Science Association Inc.The authors wish to thank the Comisión Interministerial de Ciencia y Tecnología for financial support of this investigation (Project AGF2001–1116).Peer Reviewe