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1.
Biol Sport ; 34(2): 185-196, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28566813

RESUMO

Kickboxing is one of the modern combat sports. The psychophysiological demands of a kickboxing competition require athletes to achieve high thresholds of several aspects of physical fitness. The aim of the current review is to critically analyse and appraise the kickboxer's anthropometric, physiological, physical and psychological attributes with the activity profile and injury epidemiology in order to provide practical recommendations for training as well as new areas of scientific research. The available information shows that both amateur and elite-level male kickboxers are characterized by a higher proportion of mesomorphy with a well-developed muscle mass and low body fat percentage. While there is some variation in the maximum oxygen uptake of kickboxers, moderate to high cardio-respiratory levels are reported for these athletes. Regardless of kickboxers' level, a high peak and mean anaerobic power output were reported. High-level kickboxing performance also requires well-developed muscle power in both the upper and lower limbs. Psychological factors contribute to success that requires high levels of self-confidence, motivation, dispositional hope and optimism, mental toughness/resiliency, and adaptive perfectionism. Psychological attributes also distinguished successful from less successful kickboxers. The activity-to-rest ratio was higher in elite (1:1) than both amateur and national-level (from 1:2 to 1:5) kickboxers, with no significant differences between rounds (round 1=1:4, and rounds 2 and 3=1:5) as well as between winners and losers in amateur and national-level simulated combats. These particular psychophysiological characteristics and performance aspects of kickboxers influence performance and could serve as guidance for training. Finally, kickboxing is characterized by chronic repetitive head trauma, which causes hypopituitarism due to traumatic brain injury (TBI). Future investigations into the physical, physiological and psychological characteristics related to age, gender and competitive levels of kickboxers are required to enrich the current knowledge and to help create the most suitable training programme.

2.
Plant Physiol ; 100(4): 1656-60, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16653181

RESUMO

Cabbage leaf discs (Brassica oleracea L., Capitata group) were floated adaxial side up in 0, 0.05, or 0.25 m CaCl(2) solutions at 15 degrees C for 14 d in the dark. To assess whether the delay of senescence by calcium treatment involved protection of membrane lipids, chlorophyll and protein content and the lipid composition of the membranes were determined during incubation. Chlorophyll and protein content decreased with time, in correlation with a reduction in the amount of phospholipids. The degree of unsaturation of phospholipids and free fatty acids decreased, whereas the ratio of sterol to phospholipid increased. The proportions of phospholipid classes did not change during senescence. The catabolism of phospholipids was delayed by 0.05 m calcium, but accelerated by 0.25 m, as compared to the untreated control. Based on the levels of the lipid intermediates, phospholipase D, phosphatidic acid phosphatase, lipolytic acyl hydrolase, and lipoxygenase appeared to be involved in the breakdown of phospholipids during senescence. Phospholipase D and phosphatidic acid phosphatase may be directly influenced by calcium. The calcium treatment apparently did not affect the activity of acyl hydrolase. Lipoxygenase, responsible for the peroxidation of the polyunsaturated fatty acids, was probably indirectly influenced by calcium. We conclude that the delay of senescence of cabbage leaf discs by calcium treatment involved protection of membrane lipids from degradation.

3.
J Food Prot ; 55(8): 595-600, 1992 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31071882

RESUMO

The diets of six groups of weaned mice were supplemented with ultra high temperature (UHT) milk containing a washed suspension of lactic acid bacteria (mixture of 8 strains) or with UHT milk fermented by the same strains and heat-treated or not. Control groups received physiological saline or UHT milk only. The mice were infected intranasally by Klebsiella pneumoniae AD-1 on the 13th d of feeding. The effect on the immune system (specific and nonspecific) before and after infection was evaluated by measuring the phagocytosis of alveolar macrophages (using zymosan particles) and by measuring of total immunoglobulin G and A levels in serum and in pulmonary fluid (using the enzyme-linked immunosorbent assay method). Postinfection survival was 0.7 d longer for mice receiving fermented milk than for the saline control group. The percent phagocytosis did not vary significantly, while serum immunoglobulin G levels differed between mice fed fermented milk and those fed bacterial suspensions in unfermented milk. Fermentation appears to be essential for the beneficial effects on the immune system and survival time; this effect no longer occurs after pasteurization of fermented milk.

4.
Plant Foods Hum Nutr ; 38(4): 343-53, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3237636

RESUMO

The objective of this work was to study the effect of the extraction of phenols by methanol/acetone/water and proteolysis (pepsin 1 hour; trypsin 2 hours) on the nutritional characteristics of unheated rapeseed protein as measured by weight gain, protein intake, net protein ratio, apparent digestibility and absorbed protein. The effect of proteolysis of the methanol/acetone/water extracted rapeseed protein, and the effect of mixing the methanol/acetone/water extract back with the extracted rapeseed protein was also studied. Extraction of phenolic compounds from rapeseed flour significantly improved weight gain, protein intake, net protein ratio and absorbed protein value. However, the mixing of phenolic extract with the extracted rapeseed protein did not appear to have a significant effect. Enzymatic hydrolysis (1 hour with pepsin and 2 hours with trypsin) of the raw material significantly improved the weight gain and protein intake. The combined methanol/acetone/water extraction and protein hydrolysis treatments were beneficial on all nutritional quality parameters of rapeseed protein. These results suggest that the protein-bound phenolic compounds, rather than the free phenolic compounds contribute mainly to the decrease in the nutritional values of proteins associated with phenolic compounds in raw flour before extraction.


Assuntos
Brassica/análise , Proteínas de Plantas/análise , Acetona , Animais , Interpretação Estatística de Dados , Hidrólise , Metanol , Valor Nutritivo , Fenóis , Ratos , Ratos Endogâmicos
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