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Effect of Repetitive Bouts of Exhaustive Exercise with Different Interval on Oxygen Consumption in Juvenile Southern Catfish  [PDF]
FU Shi-jian,CAO Zhen-dong,PENG Jiang-lan
Journal of Chongqing Normal University , 2009,
Abstract: The paper is to investigate the repeating locomotive capacity of warmwater sit-and-wait southern catfish ( Silurus meridionalis Chen) and to test whether post-exercise recovery status has some effects on the next bout of exhaustive exercise metabolic recovery process. The oxygen consumption ( Vo2 ) of juvenile southern catfish ( 17.64~48.21 g, n=40) after repetitive bouts of exhaustive exercise (widely accepted hand-chasing method) with different intervals (10 min interval for a series of 3 bouts, 30 min interval for a series of 2 bouts and 24 h interval for a series of 2 bouts) was investigated at (25.0±1.0)℃ by using flow through respirometer made by laboratory of evolutionary physiology and behaviour (Patent No. ZL 200520010481.0 ). The resting oxygen consumption rate (Vo2rest) is (2. 39±0.13 )to(2.83±0.31 )mg·min-1·kg-1, the peak oxygen consumption rate (Vo2peak) is (8.36±0.26) to(10.39±0.44) mg·min -1·kg-1 and the magnitude of EPOC is (66.31 + 6.37 ) to (88.89±4.61) mg·kg-1. It is found that oxygen consumption can reach a relative stable status at 20~30 min after exhaustive exercise. The pre-exercise status can achieve after 24 h recovery. The recovery rates of post-exercise oxygen consumption are higher in the second and the third bouts of exhaustive exercise compared with the first bout in all interval treatments. However, there are no significant differences in peak oxygen consumption and EPOC magnitude among different bouts of exhaustive exercise. It suggests that exhaustive exercise can elicit the maximum oxygen consumption in juvenile southern catfish.
Can neuromuscular fatigue threshold be determined by short and non-exhaustive bouts?
Fontes, Eduardo Bodnariuc;Okano, Alexandre Hideki;Smirmaul, Bruno de Paula;Altimari, Leandro Ricardo;Gon?alves, Ezequiel Moreira;Triana, Ricardo Okada;Moraes, Antonio Carlos;
Revista Brasileira de Cineantropometria & Desempenho Humano , 2012, DOI: 10.5007//1980-0037.2012v14n3p254
Abstract: the present study determined the neuromuscular fatigue threshold (nft) using four different time-periods of analysis of the electromyographic signal and compared these estimations with critical power (cp). fifteen healthy young men (73.6 ± 5.1 kg, 177.8 ± 7.0 cm, 23.4 ± 5.2 years) performed 3-4 different severe constant workload trials until exhaustion on a cycle ergometer with simultaneous semg signals acquisition. the obtained data permitted nft estimation with four different periods of analysis as follows: initial 30s (t30), 1min (t1), 2min (t2) and total time (tt), as well as cp. t30 and t1 were significantly higher than tt and cp and, t2 and tt did not differ between each other, and both were significantly higher than cp. in addition, tt was significantly correlated to cp (0.72; p < 0.05) and to t2 (0.58; p < 0.05). we conclude that nft overestimates cp, independent of the time-period analysis used for its determination.
Swimming Training Induces Liver Mitochondrial Adaptations to Oxidative Stress in Rats Submitted to Repeated Exhaustive Swimming Bouts  [PDF]
Frederico D. Lima, Daniel N. Stamm, Iuri D. Della-Pace, Fernando Dobrachinski, Nélson R. de Carvalho, Luiz Fernando F. Royes, Félix A. Soares, Jo?o B. Rocha, Javier González-Gallego, Guilherme Bresciani
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0055668
Abstract: Background and Aims Although acute exhaustive exercise is known to increase liver reactive oxygen species (ROS) production and aerobic training has shown to improve the antioxidant status in the liver, little is known about mitochondria adaptations to aerobic training. The main objective of this study was to investigate the effects of the aerobic training on oxidative stress markers and antioxidant defense in liver mitochondria both after training and in response to three repeated exhaustive swimming bouts. Methods Wistar rats were divided into training (n = 14) and control (n = 14) groups. Training group performed a 6-week swimming training protocol. Subsets of training (n = 7) and control (n = 7) rats performed 3 repeated exhaustive swimming bouts with 72 h rest in between. Oxidative stress biomarkers, antioxidant activity, and mitochondria functionality were assessed. Results Trained group showed increased reduced glutathione (GSH) content and reduced/oxidized (GSH/GSSG) ratio, higher superoxide dismutase (MnSOD) activity, and decreased lipid peroxidation in liver mitochondria. Aerobic training protected against exhaustive swimming ROS production herein characterized by decreased oxidative stress markers, higher antioxidant defenses, and increases in methyl-tetrazolium reduction and membrane potential. Trained group also presented higher time to exhaustion compared to control group. Conclusions Swimming training induced positive adaptations in liver mitochondria of rats. Increased antioxidant defense after training coped well with exercise-produced ROS and liver mitochondria were less affected by exhaustive exercise. Therefore, liver mitochondria also adapt to exercise-induced ROS and may play an important role in exercise performance.
Neuromuscular adaptations to strength and concurrent training in elderly men. DOI: http://dx.doi.org/10.5007/1980-0037.2012v14n4p483
Eduardo Lusa Cadore,Ronei Silveira Pinto,Luiz Fernando Martins Kruel
Revista Brasileira de Cineantropometria e Desempenho Humano , 2012,
Abstract: DOI: http://dx.doi.org/10.5007/1980-0037.2012v14n4p483This paper aimed to review the results of studies on neuromuscular adaptations to strength training (ST) and concurrent training (CT) in elderly men. A literature search was conducted using PubMed, Scopus, and SciELO. The search was limited to studies published from 1980 to 2012. A total of 3,390 articles were retrieved. After reading their titles, 127 studies were further evaluated by reading their abstracts. This resulted in 92 papers that were read in full; 25 of these were selected and their results were described in the present review. Several studies showed that, in elderly subjects, ST can produce increases in muscle strength, power, activation and mass. ST-induced strength gain may be explained by neural and morphological adaptations. The main neural adaptations to ST included increased recruitment of motor units and increased motor unit firing rate. Morphological adaptations included increases in the physiological cross-sectional area (CSA) of the muscle, in muscle thickness, in muscle fiber pennation angle, and changes in muscle myosin heavy-chain isoforms, resulting in the conversion of muscle fiber from subtype IIx to IIa. The inclusion of moderate-to-high inten- sity (60-85% of maximum strength) ST in the routine of this population is recommended to improve neuromuscular function. CT can promote significant neuromuscular adaptations, but these gains may be of a lower magnitude than those obtained with ST. Although CT has an interference effect on neuromuscular adaptations, it also promotes improvement in cardiovascular function and is therefore the most frequently recommended intervention for health promotion in the elderly.
Relationship between running kinematic changes and time limit at vVO2max. DOI: http://dx.doi.org/10.5007/1980-0037.2012v14n4p428
Leonardo De Lucca,Sebasti?o Iberes Lopes Melo
Revista Brasileira de Cineantropometria e Desempenho Humano , 2012,
Abstract: DOI: http://dx.doi.org/10.5007/1980-0037.2012v14n4p428Exhaustive running at maximal oxygen uptake velocity (vVO2max) can alter running kinematic parameters and increase energy cost along the time. The aims of the present study were to compare characteristics of ankle and knee kinematics during running at vVO2max and to verify the relationship between changes in kinematic variables and time limit (Tlim). Eleven male volunteers, recreational players of team sports, performed an incremental running test until volitional exhaustion to determine vVO2max and a constant velocity test at vVO2max. Subjects were filmed continuously from the left sagittal plane at 210 Hz for further kinematic analysis. The maximal plantar flexion during swing (p<0.01) was the only variable that increased significantly from beginning to end of the run. Increase in ankle angle at contact was the only variable related to Tlim (r=0.64; p=0.035) and explained 34% of the performance in the test. These findings suggest that the individuals under study maintained a stable running style at vVO2max and that increase in plantar flexion explained the performance in this test when it was applied in non-runners.
Prevalence of low physical activity level among preschool children. DOI: http://dx.doi.org/10.5007/1980-0037.2012v14n4p390
Simone Storino Honda Barros,Adair Silva Lopes,Mauro Virgilio Gomes Barros
Revista Brasileira de Cineantropometria e Desempenho Humano , 2012,
Abstract: DOI: http://dx.doi.org/10.5007/1980-0037.2012v14n4p390Physical activity (PA) in children has a decisive role in motor development and prevention of childhood obesity. The available evidence suggests that there is high preva-lence of low levels of PA in children, but little is known about the level of PA in preschool children. The objective of this study was to identify the prevalence and the factors associated with low levels of PA in preschool children. This was a cross-sectional study performed in private schools in the municipality of Olinda (state of Pernambuco), with data collection through parent’s face-to-face interviews. The study included 265 children (54.3% girls) with mean age of 4.9 years (SD=0.8). Children who did not perform at least 60 minutes/day of outdoors physical activities were considered exposed to low levels of PA. Data analysis was performed by logistic regression considering low level of PA as the outcome. The results showed that 65.3% (95%CI: 9.4-70.8) of children were classified as exposed to ‘low level of PA’. Analysis showed that higher parental education (OR=2.41; 95%CI: 1.13-5.10), lack of space for playing at home (OR=2.36; 95%CI: 1.17- 4.78), and attending school in the afternoon (OR=2.92, 95%CI 1.55-5.49) or full-time (OR=57.1, 95%CI 6.57-496.2) were associated with low levels of PA. Preschoolers from families with higher number of children had lower likelihood of low level of PA (OR=0.49; 95%CI 0.26-0.93). It can be concluded that the proportion of children exposed to low levels of PA is high compared to the results of similar studies and that parental and environmental factors are associated with physical activity level in preschool-aged children.
Judging criteria in international professional surfing championships. DOI: http://dx.doi.org/10.5007/1980-0037.2012v14n4p439
Rosemeri Peir?o,Saray Giovana dos Santos
Revista Brasileira de Cineantropometria e Desempenho Humano , 2012,
Abstract: DOI: http://dx.doi.org/10.5007/1980-0037.2012v14n4p439This study investigated the association between judges’ scores and the varia-bles that represent judging criteria of surfing events. A total of 164 waves ridden by 21 international surfers were recorded and analyzed in two stages of the Brazilian ASP World Tour (2007 and 2010). The following tests were used for descriptive analysis of data: the Kolmogorov-Smirnov and the Student t test, one-way ANOVA, the Tukey post-hoc test and Pearson correlation analysis (p≤0.05). Significant differences were found between the scores of waves with bad, average and exceptional take-offs (p≤0.05) and with controlled exit, fall in the main section of the wave (MSW) and after the MSW (p≤0.001). There was a significant correlation (p≤0.05) between wave scores and the following variables: frequency of imbalance in the maneuvers (r=-0.30), percentage of maneuvers in the critical section of the wave (r=0.68), variety of maneuvers (r=0.62), frequency of carving (r=0.51), re-entry (r=0.43), floater (r=0.23) and cut-back (r=0.27) maneuvers, length of ride (r=0.76) and total frequency of maneuvers (r=0.79) for the ASP World Tour 2007; percentage of maneuvers in the critical section of the wave (r=0.34), variety of maneuvers (r=0.70), frequency of carving (r=0.46), re-entry (r=0.51), cut-back (r=0.30) and aerial maneuvers (r=0.30), length of ride (r=0.71) and total frequency of maneuvers (r=0.75) for the ASP World Tour 2010. The results showed that all surfing criteria used by judges in this study correlated significantly with scores in the ASP World Tour 2007 and 2010, except for frequency of imbalances in the second competition.
Developmental assessment and performance analysis of vertical jump in schoolchildren. DOI: http://dx.doi.org/10.5007/1980-0037.2012v14n4p460
Pedro Paulo Depra,Dalker Roberto Walter
Revista Brasileira de Cineantropometria e Desempenho Humano , 2012,
Abstract: DOI: http://dx.doi.org/10.5007/1980-0037.2012v14n4p460The vertical jump involves different levels of skill complexity and offers the individual a wide range of motor experiences. This study aimed to determine which movements in the developmental sequence performed by schoolchildren are associated with age and vertical jump performance. The sample consisted of 137 elementary school children of both sexes, aged 7-10y, with height of 1.19-1.63 m, and weight of 20-60 kg. All children were selected from first- to fourth-grade classrooms of a public school of the city of Maringá, state of Pa- raná, Brazil. A Gallahue & Ozmun matrix and a jumping platform were used as research instruments. During the experiment, each child performed three jumps. Simultaneous and coordinated upward arm lift was observed in 7-year-old children. In 9-year-old children, inconsistent preparatory crouch and lack of coordination between limb movements and trunk were observed. A prevalence of upper limb motor acts was observed when considering the significant associations found between elements of the developmental sequence and vertical jump performance. In children aged 7-10y, age group and jumping performance are associated with elements of the developmental sequence of the human body as a whole, especially with regard to the upper limbs.
Reproducibility of auscultatory blood pressure measurement during resistance exercise. DOI: http://dx.doi.org/10.5007/1980-0037.2012v14n4p450
Danyele Moura de Andrade,Annelise Lins Meneses,Tarciso Rogério Medeiros de Almeida,Alessandra de Souza Miranda
Revista Brasileira de Cineantropometria e Desempenho Humano , 2012,
Abstract: DOI: http://dx.doi.org/10.5007/1980-0037.2012v14n4p450The auscultatory method has been suggested as a viable option for blood pressure (BP) measurement during resistance exercise. However, indicators of reproducibility of this method during resistance exercise have not been established. This study aimed to analyze intra- and inter-examiner reproducibility of auscultatory BP measurements obtained du-ring resistance exercise. Fourteen subjects (24 ± 5 years; 22.0 ± 2.4 kg/m2; systolic BP, 116 ± 7 mmHg; diastolic BP, 75 ± 4 mmHg) performed three sets of 15 repetitions of the knee extension exercise at 50% of their 1-repetition maximum at two different time points (T1 and T2). Before and during exercise, systolic and diastolic BP were measured simultaneously in both arms by two examiners. The intra-examiner intraclass correlation coefficient (ICC) for systolic BP was 0.75 (0.57-0.86) and 0.76 (0.59-0.87) for examiners 1 and 2, respectively. In addition, systolic BP values were similar at T1 and T2 both for examiner 1 (144 ± 9 vs. 146 ± 18, p = 0.08) and examiner 2 (152 ± 9 vs. 153 ± 12, p = 0.32). Inter-examiner ICC was 0.68 (0.46-0.82) for systolic BP and 0.21 (0.11-0.50) for diastolic BP. It can be conclu-ded that auscultatory systolic BP measurement during resistance exercise shows intra- and inter-examiner reproducibility ranging from 0.68 to 0.76, whereas diastolic BP measurement during resistance exercise shows low reproducibility.
Individual and environmental factors associated with park and plaza use in adults from Curitiba, Brazil. DOI: http://dx.doi.org/10.5007/1980-0037.2012v14n4p377
Rogério César Fermino,Rodrigo Siqueira Reis,Ana Carina Cassou
Revista Brasileira de Cineantropometria e Desempenho Humano , 2012,
Abstract: DOI: http://dx.doi.org/10.5007/1980-0037.2012v14n4p377The aim of this study was to identify individual and environmental factors associated with park and plaza use in adults from Curitiba, state of Paraná, Brazil. A cross-sectional study was conducted in 2008 with 749 participants (59.9% men) selected in areas for physical activity (PA) in four parks and four plazas. Poisson regression was used to examine the associations of sociodemographic (sex, age, education) and health (body mass index, perceived health) variables, company for park/plaza use, access (perception of distance, access and commuting to the places), and leisure time PA (walking and moderate/ vigorous PA - MVPA) with frequent use of parks and plazas (≥1 time/wk). The percentage of park and plaza use was 68%, and company (PR: 0.74; CI95%: 0.62-0.89) and higher levels of walking (PR: 1.30; CI95%: 1.03-1.64) and MVPA (PR: 1.39, CI95%: 1.07-1.80) were asso-ciated with the use of the places. These results can be used to guide interventions aimed at providing services and facilities for PA practice in parks and plazas.
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