The objective of this study was to verify the influence of the natural antioxidant, hidro-etanolic extract of yerba-mate (Ilex paraguariensis St. Hil), on the lipid oxidation, cholesterol content and profile of the fatty acids, of the meat of cut chickens, when submitted the dietary with natural antioxidant. The results of cholesterol assays the of chicken breast had varied of 32.17 the 52.90 mg/100g of meat, and 42.21 the 68.59 mg/100g of meat in the thigh cuts. The treatment with 0,3% of natural antioxidant for the chicken breast differed from the others treatments, getting low the cholesterol. The results of the test of inhibition of the oxidation had been of 21.81%, 63.64% and 50.91% respectively for 0.3%, 0.5% and 0.7% of the natural antioxidant. The treatment with 0.7% of natural antioxidant, has presented the greater total phenols concentration (10.56g/ml), followed for treatments 0.5% (7.71g/ml) and 0.3% (5.29g/ml). The natural antioxidant provided a reduction of the cholesterol in the chicken meat, behavior that can be explained by potential the biological effect of phenolic composites as kidnapping of free radicals, acting in such a way in the stage of initiation as in the propagation of the oxidation process. These results suggest, therefore, an antioxidant effect of phenols identified in the extract hidro-etanolic of yerba-mate, on the mechanism of formation of the in vivo cholesterol of chickens. The natural antioxidant exerted a preponderant influence on the oxidation quality of the chicken meat, during the period of storage under refrigeration and freezing. The values of pH if had kept normal, the TBARS (2-thiobarbituric acid) suffered to a considerable increase with variation from 0.117- 1.053mg of malondialdehyde /kg and 0.078-0.780mg of alondialdehyde /kg for breast and thigh of chicken respectively, indicating reduction in the oxidation speed of the meat. In the period of freezing the values of TBARS for the thigh cut, (trat. 0.3%), greater stability was observed, an variation of 0.117-0.234 mg of malondialdehyde /kg until the two months of freezing, after this period was raised until 0.780mg of malondialdehyde /kg. The prolife fatty acid polyunsaturated n-3, in the cuts of chest of chicken (trat.0.3%) and greater insaturated fatty acid content. Was observed twenty six (26) fatty acid in the cuts of the breast and thigh of chicken. The fatty acid, C16:1, C18:1 , C18:2, C22:5 (DPA), C18:3 e C20:4, they had been found in greater porcentage that the other fatty acid in the cuts of chicken breast (trat. 0.3%) the percentage acid monoinsaturado oleic, of the family n-9, it presented higher level (2.10g/100g) that the observed in literature. Of this form it is possible to consider the use of the natural antioxidant of yerba-mate, with the purpose to have meats and products meat with important functional properties for the health human being. / O objetivo deste trabalho foi verificar a influência do antioxidante natural, extrato hidro-etanólico de erva mate (Ilex paraguariensis St. Hil), sobre a oxidação lipídica, conteúdo de colesterol e perfil dos ácidos graxos, da carne de frangos de corte, quando submetidos á dieta com antioxidante natural. Os resultados dos teores de colesterol nos cortes de peito variaram de 32,17 a 52,90 mg/100g de carne, e de 42,21 a 68,59 mg/100g de carne nos cortes de coxa. O tratamento com 0,3% de antioxidante para o peito de frango diferiu dos demais tratamentos, obtendo o menor teor de colesterol. Os resultados do teste de inibição da oxidação foram de 21,81%, 63,64% e 50,91% respectivamente para 0,3%, 0,5% e 0,7% do antioxidante natural. O tratamento com 0,7% de antioxidante, apresentou a maior concentração de fenóis totais (10,56g/ml), seguidos pelos tratamentos 0,5% (7,71g/ml) e 0,3% (5,29g/ml). O antioxidante natural proporcionou uma diminuição do colesterol na carne de frango,comportamento que pode ser explicado pelo efeito biológico potencial dos compostos fenólicos como seqüestradores de radicais livres, agindo tanto na etapa de iniciação como na propagação do processo oxidativo. Estes resultados sugerem, portanto, um efeito antioxidante dos fenóis identificados no extrato hidro-etanólico de erva mate, sobre o mecanismo de formação do colesterol in vivo de frangos. O antioxidante natural exerceu uma influência preponderante sobre a qualidade oxidativa da carne de frango durante o período de armazenamento sob refrigeração e congelamento. Os valores de pH se mantiveram normais, o TBARS (substâncias reativas ao ácido tiobarbitúrico) sofreu um aumento considerável com variação de 0,117 a 1,053mg de malonaldeido/kg e de 0,078 a 0,780mg de malonaldeido/kg para peito e coxa de frango respectivamente, indicando diminuição na velocidade oxidativa da carne. No período de congelamento os valores de TBARS para os corte de coxa (trat. 0,3%), observou-se maior estabilidade, uma variação de 0,117 a 0,234mg de malonaldeido/kg até os dois meses de congelamento, após este período elevou-se até 0,780mg de malonaldeido/kg. O perfil de ácidos graxos mostrou aumento no conteúdo dos ácidos graxos poliinsaturados ômega 3 nos cortes de peito de frango (trat.0,3%) e maior conteúdo de ácidos graxos insaturados. Foram detectados vinte e seis (26) ácidos graxos nos cortes de peito e coxa de frango. Os ácidos graxos C16:1, C18:1 , C18:2, C22:5 (DPA), C18:3 e C20:4 foram encontrados em maior porcentagem que os demais ácidos graxos nos cortes de peito de frango (trat. 0,3%) o percentual do ácido monoinsaturado oléico , da família ômega-9, apresentou teores mais elevados (2,10g/100g) que os encontrados na literatura. Desta forma é possível propor a utilização do antioxidante natural de erva mate, com a finalidade de obter carnes e produtos cárneos com propriedades funcionais importantes para a saúde humana.

Background: Epidemiological findings indicate a higher risk of muscular thigh strain injury during the latter stages of both halves of soccer match-play, with muscular fatigue highlighted as a key etiological factor in injury causation. Anthropometric, biomechanical and physiological differences present in the Black African population may elicit unique thigh injury risk profiles, different from those of European and American players. Objectives: The purpose of the current research was to investigate the impact of soccer-specific fatigue on the risk of hamstring and quadricep injury in amateur Black African soccer players, in both the dominant and non-dominant legs. Methods: Participants were required to perform a soccer matchplay simulation (SAFT⁹⁰), consisting of multidirectional and utility movements, as well as frequent acceleration and deceleration. Selected physical, physiological and psychophysical responses were collected at specific time intervals throughout fatigue protocol performance. Results: Heart rate responses were observed to increase significantly (p<0.05) in response to the start of both halves, and remain elevated (but showing no further significant increase) during the performance of the remainder of the fatigue protocol. Significant (p<0.05) changes in both concentric and eccentric isokinetic variables of the knee flexors and extensors highlight the effect of muscular fatigue on performance in soccer match-play. Eccentric hamstring peak torque was observed to decrease significantly over time (60°.s⁻ₑ=17.34%, 180°.s⁻ₑ=18.27%), with significant reductions observed during both halves. The functional H:Q ratio at 180°.s⁻ₑ indicated a significant decrease over time (10.04%), with a significant decrease indicated during the second half of the SAFT⁹⁰ protocol. The passive half time interval did not result in significant changes in isokinetic variables. Isokinetic strength, work and power indicated no significant effects of leg dominance.. ‘Central’ and ‘Local’ ratings of exertion were observed to increase significantly (p<0.05) as a function of exercise duration. Conclusion: The overall reduction in both the eccentric hamstring peak torque and the functional strength ratio was illustrated to be similar to that of other soccer-specific fatigue research. As a result, the risk of thigh strain injuries is suggested to be similar regardless of playing level and race. These time dependent changes may have implications for competitive performance and increased predisposition to hamstring strain injuries during the latter stages of both halves of match-play

No description available.

The purpose of this experiment was to investigate skeletal muscle blood flow and glucose uptake in m. biceps (BF) and m. quadriceps femoris (QF) 1) during recovery from high intensity cycle exercise, and 2) while wearing a compression short applying ~37 mmHg to the thigh muscles. Blood flow and glucose uptake were measured in the compressed and non-compressed leg of 6 healthy men by using positron emission tomography. At baseline blood flow in QF (P = 0.79) and BF (P = 0.90) did not differ between the compressed and the non-compressed leg. During recovery muscle blood flow was higher compared to baseline in both compressed (P&lt;0.01) and non-compressed QF (P&lt;0.001) but not in compressed (P = 0.41) and non-compressed BF (P = 0.05; effect size = 2.74). During recovery blood flow was lower in compressed QF (P&lt;0.01) but not in BF (P = 0.26) compared to the non-compressed muscles. During baseline and recovery no differences in blood flow were detected between the superficial and deep parts of QF in both, compressed (baseline P = 0.79; recovery P = 0.68) and non-compressed leg (baseline P = 0.64; recovery P = 0.06). During recovery glucose uptake was higher in QF compared to BF in both conditions (P&lt;0.01) with no difference between the compressed and non-compressed thigh. Glucose uptake was higher in the deep compared to the superficial parts of QF (compression leg P = 0.02). These results demonstrate that wearing compression shorts with ~37 mmHg of external pressure reduces blood flow both in the deep and superficial regions of muscle tissue during recovery from high intensity exercise but does not affect glucose uptake in BF and QF. © 2013 Sperlich et al. / <p>:doi 10.1371/journal.pone.0060923</p>