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1.
A complex study of the physical working capacity of five- to six-year-old children (n = 106) was performed. It was found that the physical working capacity of preschool children at this age is determined by the following five major factors: (I) aerobic capacity, (II) anaerobic glycolytic working capacity, (III) absolute aerobic power, (IV) relative aerobic power, and (V) anaerobic alactic working capacity. Sex-related differences in some parameters reflecting the physical working capacity and fitness, characterizing the anaerobic alactic and anaerobic glycolytic productivity of the body were revealed. These differences are apparently related to an advanced development of anaerobic energy-supply mechanisms of girls compared to age-matched boys. The procedure of a complex assessment of the physical working capacity of five- to six-year-old children has been developed, which includes informative parameters characterizing the power and capacity of energy systems selected on the basis of results of factor analysis and expert assessment. A rapid procedure for a complex assessment of working capacity based on calculating the time during which a physical load (2 W/kg) can be sustained is proposed. The study showed that shifts in the intensity of physical activity within the optimal range resulted in multifold changes in its duration. Importantly, the duration of physical activity’s performance at an intensity of 175–180 bpm in children with a high working capacity is comparable to the maximum work duration at a heart rate of 140–145 bmp in preschool children with a low physical condition. Differences between children with high and low physical working capacity were found to increase with an increase in the physical load aerobicity. The physical working capacity of five- to six-year-old children can be differentiated best of all on the basis of aerobic capacity parameters. The enormous range of changes in the aerobic capacity parameters makes them especially valuable for characterizing the level of somatic health of preschool children. The results of this study were used to construct a nomogram for the determination of the allowable training load depending on its intensity and physical working capacity.  相似文献   

2.
The energy supply for muscle activity in healthy boys aged 13–14 years (n = 162) at various puberty stages (PSs) has been studied using functional and ergometric working capacity indices. It has been established that boys at PSs II–IV significantly differ in the indices of power, capacity, and efficiency of bioenergy systems. Three groups of bioenergy indices have been distinguished that differ in the direction of variations in adolescents depending on the rate of puberty. The first group includes the physiological variables the highest levels of which are observed in adolescents with high rates of development. All these indices belong to the anaerobic alactic and anaerobic glycolytic components of physical capability. The second group includes the physiological variables the highest levels of which are observed in adolescents with medium rates of development; the lowest levels, in adolescents with accelerated rates of development. These indices mainly reflect the set of aerobic capacities. The third group includes the physiological variables the highest levels of which are observed in adolescents with low rates of development and the lowest levels, in boys with accelerated rates of maturation. These indices reflect the maximal aerobic power and endurance. It was found that adolescents aged 13–14 years with moderate rates of development are characterized by higher indices of power and capacity of the aerobic energy supply system as compared to adolescents with accelerated maturation. This group of adolescents has also been observed to exhibit a lower maximal aerobic power against a background of higher capacity and efficiency of the aerobic system functioning as compared to adolescents with slow maturation. Adolescents with moderate rates of maturation have been shown to surpass schoolboys with accelerated or slow development with respect to the power of mixed aerobic-anaerobic work. Boys aged 13–14 years with accelerated development have been found to differ from schoolboys with moderate or slow maturation by high anaerobic capacity, relatively low aerobic capacities and an increase in the tone of the parasympathetic nervous system. This should be taken into consideration in terms of a differentiated approach to the formation of load during physical education and athletic training of adolescents aged 13–14 years.  相似文献   

3.
In work on the basis of use functional and ergometric working capacity indicators specificity of power supply of muscular activity of healthy boys of 13-14 years (n = 162) with various at puberty stages (PSs). It is established, that the boys, being on II-IV PSs, considerably differ on indicators of power, capacity and efficiency of energy systems. Three groups of the bioenergy systems indicators differing on an orientation of their changes at teenagers depending on rates of puberty stages. The first group includes the physiological variables which most considerable levels are observed at children with high rates of development. All of them concern to anaerobic alactic and anaerobic glycolytic to components of physical working capacity. The second group unites the physiological variables which highest values are marked at teenagers with average rate of development, and the least--at children with the accelerated rate of maturing. These indicators reflect, mainly, set of aerobic possibilities of an organism. The third group includes the indicators which highest levels are marked at teenagers with low rate of development, and the least--at boys with the accelerated rate of maturing. They reflect the maximum aerobic power and endurance to power work. It is revealed, that teenagers of 13-14 years with average rates of development are characterised in comparison with children with the accelerated maturing, higher indicators of power and capacity of aerobic system of energy-supply, and in comparison to teenagers to the slowed down development--lower maximum aerobic power against higher capacity and profitability of functioning of aerobic system. Adolescents with average rates of maturing surpass also schoolboys with the accelerated and slowed down development concerning capacity of work in mixed anaerobic-aerobic a mode. In turn boys of 13-14 years with the accelerated development differ from schoolboys with the average and slowed down rates of maturing, high anaerobic productivity of an organism, rather low aerobic possibilities and increase of a tone of parasympathetic department of autonomic nervous system (AHC). The given circumstance is necessary for considering at realisation of the differentiated approach to rationing of loadings in the course of physical education and sports training of adolescents of 13-14 years.  相似文献   

4.
The study aimed at optimizing the functional state (FS) of anxious six- to eight-year-old children showed that integrated use of physical exercises of a mainly aerobic character, relaxation training, respiratory exercises, and functional music is more effective in the long-term aspect than selective use of these means. Only physical exercises exert a marked influence in the FS of six- to eight-year-old anxious children under a stressful informational load. The use of other means of optimizing the FS appears to be less effective. The high effectiveness of physical exercises is determined by adaptive changes in the mechanisms of FS regulation in anxious children. Apparently, long-term adaptation to an adequate muscular activity ensures improved functioning of, and a better interaction between, the activating and inactivating structures of the modulating brain system located at different levels of the CNS, in particular, in the frontal cortical areas. It is emphasized that the peculiarities of the influence of different means of regulation of the FS on the body of anxious elementary school children are, largely determined by the immaturity of the frontothalamic regulatory system and the specifics of the functional organization of the limbic brain structures.  相似文献   

5.
We determined the independent factors that reflect the fundamental characteristics of the functional state (FS) in adolescents aged 13–14 years (n = 162): the sympathetic regulation and parasympathetic regulation of FS, physical working capability; the efficiency of cognitive performance; the hemodynamic basis of cognitive activity; nonspecific resistance to upper respiratory tract infections. Using the systematic approach, we investigated the physiological basis of these factors and determined the indices suitable for estimating the FS of adolescents at different stages of puberty. We observed progressive dynamics of FS parameters related to factors listed above in boys of the same chronological age at different puberty stages. Beginning from stage II to stage IV, we observed a heterochronic and nonlinear decrease in the tension of system of autonomic FS regulation, an increase in the efficiency of cognitive activity and its hemodynamic supply, as well as an improvement of anaerobic working capability.  相似文献   

6.
Regulation of fermentative capacity was studied in chemostat cultures of two Saccharomyces cerevisiae strains: the laboratory strain CEN.PK113-7D and the industrial bakers’ yeast strain DS28911. The two strains were cultivated at a fixed dilution rate of 0.10 h−1 under various nutrient limitation regimes: aerobic and anaerobic glucose limitation, aerobic and anaerobic nitrogen limitation on glucose, and aerobic ethanol limitation. Also the effect of specific growth rate on fermentative capacity was compared in glucose-limited, aerobic cultures grown at dilution rates between 0.05 h−1 and 0.40 h−1. Biomass yields and metabolite formation patterns were identical for the two strains under all cultivation conditions tested. However, the way in which environmental conditions affected fermentative capacity (assayed off-line as ethanol production rate under anaerobic conditions) differed for the two strains. A different regulation of fermentative capacity in the two strains was also evident from the levels of the glycolytic enzymes, as determined by in vitro enzyme assays. With the exception of phosphofructokinase and pyruvate decarboxylase in the industrial strain, no clear-cut correlation between the activities of glycolytic enzymes and the fermentative capacity was found. These results emphasise the need for controlled cultivation conditions in studies on metabolic regulation in S. cerevisiae and demonstrate that conclusions from physiological studies cannot necessarily be extrapolated from one S. cerevisiae strain to the other.  相似文献   

7.
S E Davies  K M Brindle 《Biochemistry》1992,31(19):4729-4735
The influence of 6-phosphofructo-1-kinase on glycolytic flux in the yeast Saccharomyces cerevisiae was assessed by measuring the effects of enzyme overexpression on glucose consumption, ethanol production, and glycolytic intermediate levels under aerobic and anaerobic conditions. Enzyme overexpression had no effect on glycolytic flux under anaerobic conditions, but under aerobic conditions, it increased glycolytic flux up to the anaerobic level. The Pasteur effect was thus abolished in these cells. The increased glycolytic flux was accompanied by a compensatory decrease in flux in oxidative phosphorylation. The concentrations of the enzyme substrates showed only small or insignificant changes. These data imply that the enzyme has a low flux control coefficient for glycolysis. However, in cells overexpressing the enzyme, there was a compensatory decrease in 6-phosphofructo-2-kinase activity which was accompanied by a corresponding decrease in fructose 2,6-bisphosphate concentration. Measurements in vitro showed that the decrease in the concentration of this positive allosteric effector of 6-phosphofructo-1-kinase could significantly lower its specific activity in the cell and that this could compensate for the increased enzyme concentration in the overproducer.  相似文献   

8.
A method was used for organizing training for aerobic working capacity. Its salient feature was individualization of the main components of the training process: dosing of the physical load at a level of 90–95% of the anaerobic threshold and optimizing the duration of rest on the basis of revealing the phase of superrecovery of the aerobic working capacity. The study, which enrolled 64 healthy males and females aged 16–20 years, provided evidence for the high effectiveness of the method. After 12 weeks of training, the anaerobic threshold, the systolic work index, and the results of Cooper’s 12-min test increased, respectively, by 9.7, 24, and 16% in the males and by 9.2, 32, and 25% in the females. The method of organizing the training process is proposed not only for the development of aerobic working capacity in healthy individuals but also for primary and secondary prophylaxis of cardiovascular diseases such as arterial hypertension and atherosclerosis.__________Translated from Fiziologiya Cheloveka, Vol. 31, No. 4, 2005, pp. 131–133.Original Russian Text Copyright © 2005 by El’chaninova, Varshavskii, Ladanov, Kalachev, Filippova.  相似文献   

9.
The psychophysiological cost of activity was determined in 5- to 14-year-old children and adolescents (n = 612) by correlating the performance of intense information load with the value of autonomic shifts in the course of the test. It was shown that the psychophysiological cost of information load in the state of functional comfort (self-determined speed) decreased 2.2- to 5.4-fold in the period from 5–6 to 13–14 years of age and the psychophysiological cost of intense intellectual activity with the maximum speed under the conditions of a time deficit (the maximum speed) decreased 1.2- to 4-fold. The greatest changes in the psychophysiological cost of intense intellectual activity were observed at the beginning of regular schooling and during puberty. The data indicate the need for a continuous search for new, efficient, and more physiologically adequate ways of control of the process of training and education taking into consideration the psychophysiological cost of intense academic activity in different periods of ontogeny and ensuring a beneficial effect of educational technologies on the health and development of schoolchildren.  相似文献   

10.
The ability of human skeletal muscle to provide anaerobically derived ATP during short-term, intense activity is examined. The paper emphasizes the information obtained from direct measurements of substrates, intermediates, and products of the pathways in muscle that provide anaerobically derived ATP. The capacity of muscle to provide ATP via anaerobic pathways is approximately 370 mmol/kg dry muscle (dm) during dynamic exercise lasting approximately 3 min. Anaerobic glycolysis provided approximately 80%, phosphocreatine (PCr) degradation approximately 16%, and depletion of the ATP store approximately 4% of the total ATP provided. When the blood flow to the working muscles is reduced or occluded, the anaerobic capacity decreases to approximately 300 mmol/kg dm. This reduction is due to a lower glycolytic capacity associated with an inability to remove lactate from the muscles. Directly measured maximal rates of anaerobically derived ATP provision from PCr degradation and glycolysis during intense muscular activity are each approximately 9-10 mmol.kg-1 dm.s-1. Evidence suggests that both of these pathways are activated instantaneously at the onset of maximal activity. Spring training does little to the capacity or rates of the pathways, although a 10-20% increase in glycolytic ATP provision has been reported. The only study comparing direct and indirect estimates of the anaerobic capacity in humans suggests that O2 deficit measured at the mouth accurately predicts the anaerobic capacity of a single muscle group and that O2 debt does not. There are many unresolved issues regarding the capacity of the PCr and glycogenolytic--glycolytic systems to provide ATP during short-term intense muscular activity in humans.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

11.
The psychophysiological condition of first-year students (males) going or not going in for sport in the course of training was investigated. Baevskii’s method was used to determine the level of stress of regulatory mechanisms. The functional level of the nervous system, the stability of neural responses, and the level of functional abilities of the developed functional system were evaluated using the variation chronoreflexometric method. It was established that an improvement in the mental capacity parameters (increased mental capacity, reduction in the number of errors, an increase in the level of functional abilities, and shortening of the latent period of visuomotor response) was accompanied by an increase of stress of the body regulatory systems, which was more marked in individuals with a low level of physical activity. This fact indicates that physical activity reduces the cost of the adaptation of the body to permanently changing environmental conditions. The optimal human adaptive systemic reactions are ensured by the dynamic interaction of the functional systems forming complex correlations in the somatic, autonomic, motor, and psychoemotional spheres of the body’s activity.  相似文献   

12.
In the research directed on optimisation of a functional state (FS) of disturbing children of 6-8 years, complex application of physical activities of mainly aerobic character, relaxation training is shown, that, respiratory exercises and functional music in long-term aspect selective use of considered means possesses more efficiency. At selective influence the expressed influence on FS disturbing children of 6-8 years in the conditions of intense information loading is rendered only by physical exercises. Application of other ways of optimisation FS is less effective. High effectiveness of use of physical exercises is caused by adaptable changes of mechanisms of regulation FS of disturbing children. Apparently, long-term adaptation to adequate muscular activity provides improvement of functioning and perfection of interaction activating and nonactivating structures of modulating system of the brain, localised on different levels the central nervous system (CNS) and, in particular, frontal departments of a bark. It is underlined, that features of influence of various receptions of regulation FS on an organism of disturbing children of younger school age are substantially caused by immaturity frontocortical-thalamic regulating system and specificity of the functional organisation limbic brain structures.  相似文献   

13.
Summary In this communication, the results of an enzyme histochemical study on the working myocardial fibres and Purkinje fibres of the atrioventricular conducting system of the human heart under ischaemic and inflammatory conditions are presented. The material was selected from patients showing changes which could be classified in three major groups: (1) early changes due to acute ischaemia either in the myocardial fibres or in the conducting system or in both; (2) chronic ischaemic changes due to cardiovascular insufficiency, such as old infarction, or coronary arteriosclerosis or both; and (3) inflammatory conditions such as myocarditis.The activity and location of about 20 enzymes that play a role in the aerobic and anaerobic pathways of energy metabolism were examined. The activity and location of some hydrolytic enzymes and the glycogen and lipid content were also studied.The most important findings were an obvious depletion of the glycogen reserves under acute ischaemic changes in both types of fibre. This was associated with a transient or permanent reduction in activity of many enzymes that play a role in aerobic and anaerobic metabolism. Further, there was an instantaneous and persistent increase in the activity of the NADPH-regenerating enzymes of the pentose phosphate pathway and of glyceraldehyde-3-phosphate dehydrogenase, the rate-limiting enzyme of glycolysis under ischaemic conditions. Chronic ischaemic changes were characterized by a gradual long-term increase in the activity of many anaerobic glycolytic enzymes. Moreover, there was an absence of activity of acetylcholine esterase immediately after the onset of infarction in the fibres of the conducting system. Lastly, a slight increase in lipid content was found in the hypertrophic chronic ischaemic fibres and in old infarcted areas. Cardiac fibres in inflamed areas showed a marked increased activity of the pentose phosphate shunt enzymes and a less pronounced increased activity of most anaerobic and hydrolytic enzymes. In contrast to the cardiac fibres in infarcted areas, the fibres in inflamed areas did not reveal a decrease or absence of activity of aerobic enzymes such as succinate dehydrogenase.  相似文献   

14.
The filamentous fungus Fusarium oxysporum is known for its ability to produce ethanol by simultaneous saccharification and fermentation (SSF) of cellulose. However, the conversion rate is low and significant amounts of acetic acid are produced as a by-product. In this study, the growth characteristics of F. oxysporum were evaluated in a minimal medium using glucose as the sole carbon source in aerobic, anaerobic and oxygen-limited batch cultivations. Under aerobic conditions the maximum specific growth rate was found to be 0.043 h(-1), and the highest ethanol yield (1.66 mol/mol) was found under anaerobic conditions. During the different phases of the cultivations, the intracellular profiles were determined under aerobic and anaerobic conditions. The profiles of the phosphorylated intermediates indicated that there was a high glycolytic flux at anaerobic growth conditions, characterized by high efflux of glyceraldehyde-3-phosphate (G3P) and fructose-6-phosphate (F6P) from the pentose phosphate pathway (PPP) to the Embden-Meyerhof-Parnas (EMP) pathway, resulting in the highest ethanol production under these conditions. The amino acid profile clearly suggests that the TCA cycle was primarily active under aerobic cultivation. On the other hand, the presence of high levels of gamma-amino-n-butyric acid (GABA) under anaerobic conditions suggests a functional GABA bypass and a possible block in the TCA cycle at these conditions.  相似文献   

15.
The characteristics of the physical state were studied in 13- to 14-year-old adolescents with high (n = 97) and low (n = 85) stress reactivities. The data showed that, during the period of sexual maturation, the development of the mechanisms of energy for muscular activity was heterochronic and nonlinear. Hyperreactive boys exhibited relatively high anaerobic nonlactic and low aerobic capacities of the body and enhanced physiological costs of the high-power function. In hyperreactive adolescents, the motor function was specifically characterized by a combination of a high level of movement speed and power and a relatively low level of general endurance. In 13- to 14-year-old adolescents, the differences in muscular working capacities and motor abilities, associated with various stress reactivity, appear during different sexual maturation stages (SMSs). At SMSs II and III, hyper- and hyporeactive adolescents exhibit higher indices of aerobic body capacities and relatively low anaerobic capacities as compared to the children at SMS IV. It is supposed that, in the hyperreactive adolescents, the efficiency of the mechanisms of body protection from hypoxia is lower.  相似文献   

16.
Immunodiffusion tests conducted under aerobic conditions demonstrated that cross-reactive material to antiserum prepared against the MoFe protein component of nitrogenase from soybean nodule bacteroids was detectable in extracts of free-living Rhizobium japonicum cells cultured in a standard medium under: aerobic conditions; aerobic conditions with nitrate; aerobic conditions with ammonia; anaerobic conditions with nitrate; and anaerobic conditions with nitrate and ammonia. The most intense precipitin bands resulted from cross-section of the antiserum with extracts of cells cultured anaerobically with nitrate or anaerobically with ammonia and nitrate. Immunodiffusion experiments with crude bacteroid extract and purified MoFe protein revealed a greater number of precipitin bands in tests conducted under aerobic conditions than those conducted under anaerobic conditions. These results indicate that some of the cross-reactive material observed under aerobic conditions resulted from breakdown of the MoFe protein. Bacteroid extracts of nodules from plants supplied with ammonia exhibited only a trace of nitrogenase activity. The addition of an excess of the Fe protein component of nitrogenase, however, resulted in a 270-fold enhancement of activity indicating the presence of active MoFe protein in these extracts.Our experiments together with results published elsewhere provide evidence that the genetic information for synthesis of a part of the MoFe component of nitrogenase is carried by Rhizobium.  相似文献   

17.
Painted turtles hibernating during winter may endure long-term exposure to low temperature and anoxia. These two conditions may affect the aerobic capacity of a tissue and might be of particular importance to the cardiac muscle normally highly reliant on aerobic energy production. The present study addressed how hibernation affects respiratory characteristics of mitochondria in situ and the metabolic pattern of turtle myocardium. Painted turtles were acclimated to control (25 degrees C), cold (5 degrees C) normoxic and cold anoxic conditions. In saponin-skinned myocardial fibres, cold acclimation increased mitochondrial respiratory capacity and decreased apparent ADP-affinity. Concomitant anoxia did not affect this. Creatine increased the apparent ADP-affinity to similar values in the three acclimation groups, suggesting a functional coupling of creatine kinase to mitochondrial respiration. As to the metabolic pattern, cold acclimation decreased glycolytic capacity in terms of pyruvate kinase activity and increased lactate dehydrogenase (LHD) activity. Concomitant anoxia counteracted the cold-induced decrease in pyruvate kinase activity and increased creatine kinase activity. In conclusion, cold acclimation seems to increase aerobic and decrease anaerobic energy production capacity in painted turtle myocardium. Importantly, anoxia does not affect the mitochondrial functional integrity but seems to increase the capacity for anaerobic energy production and energy buffering.  相似文献   

18.
The effects of culture conditions (aerobic or anaerobic) and glucose in the medium on the production of spirosomes in Escherichia coli B were studied by SDS-PAGE and electron microscopy. The Mr of the spirosome of E. coli B was estimated to be 97,000. Electron microscopy revealed that the amount of spirosomes derived from anaerobic cultures was about eightfold larger than that from aerobic cultures. In SDS-PAGE, the bands of spirosome protein derived from anaerobic cultures were more intense than those derived from aerobic cultures, either in peptone water or in Davis-Mingioli's minimal medium. With increased glucose concentration under aerobic conditions, the intensity of the band of spirosome protein was similar to that observed under anaerobic conditions in basal media. These results suggest that spirosome production by E. coli B is related to its anaerobic glycolysis activity.  相似文献   

19.
1. The concentrations of some phosphorylated glycolytic intermediates and of NADH were measured in glycolysing rat liver slices. 2. In anaerobically incubated liver slices the concentration of hexose monophosphates decreases during the first 20min. of incubation, whereas the concentrations of fructose diphosphate and triose phosphates increase progressively. 3. In liver slices from fed rats, previously exposed to oxygen, the stimulated anaerobic glycolysis is accompanied by an increase in the concentration of hexose monophosphates; fructose diphosphate and triose phosphates maintain the concentrations reached at the end of the aerobic preincubation. 4. The same pattern in the concentration of glycolytic phosphorylated intermediates is seen under all conditions where aerobic preincubation brings about a stimulation of anaerobic glycolysis. A similar pattern is also found in liver slices from fed rats incubated anaerobically in the presence of fructose; these slices display a high glycolytic activity, which is not further affected by previous aerobic incubation. 5. The concentration of NADH decreases in liver slices during exposure to oxygen; during the subsequent anaerobic glycolysis the concentration increases but is always lower in preincubated than in non-preincubated liver slices. 6. The results of the present experiments suggest that the limiting step mainly affected by the preliminary exposure to oxygen might be at the level of the utilization of triose phosphates.  相似文献   

20.
Research on studying influence of the rate of muscular training in conditions of additional resistive resistance to breath on a level of physical working capacity, aerobic productivity and a functional condition of system of breath was performed. It is shown, that regular muscular loadings in a combination to resistive resistance to breath in a mode of an interval exposition provide an increase of profitability and efficiency of functioning of breathing system as expressed in increase of expiratory force respiratory muscles, rationalization of parity of volumetric-time parameters of breath pattern that promotes more effective gas exchange and decrease in power cost of respiratory movements and as a result leads to increase in aerobic productivity and growth of the general and special working capacity. At continuous exposition of resistive resistance against a background of muscular training, the increase of inspiratory force of respiratory muscles, increase of functional capacity of system of breath were revealed at physical activity as well as a significant gain of the general physical working capacity.  相似文献   

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