187 research outputs found

    HEART RATE DYNAMICS BY NOVEL CHAOTIC GLOBALS TO HRV IN OBESE YOUTHS

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    Objective: this study aimed to assess the heart rate dynamics in young obese subjects by novel chaotic globals to HRV. Methods: eighty-six young subjects were distributed in two equal groups (n = 43) according to the nutritional status: obese and control following Body Mass Index. For the analysis of HRV indexes, the heart rate was recorded heartbeat to heartbeat with the young resting in dorsal (prone) position for 30 minutes. Results: after Anderson-Darling and Lilliefors tests, the data was deemed non-normal. So, Kruskal-Wallis test of significance was applied for the statistical analysis, level set at (p < 0.01). Principal Component Analysis (PCA) identified two components represented 100% of total variance. The algorithm which applies all three parameters is suggested as the most influential and statistically very significant at the level (p < 0.001); it also elevates the chaotic response. Conclusion: youth obesity increases the chaotic response. The reasons for the study include quantitative assessment to allow effective dietary, pharmacological or even surgical intervention in the condition

    Complex measurements of heart rate variability in obese youths: Distinguishing autonomic dysfunction

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    Introduction. Heart rate variability (HRV) can be assessed from RR-intervals. These are derived from an electrocardiographic PQRST-signature and can deviate in a chaotic or irregular manner. In the past, techniques from statistical physics have allowed researchers to study such systems.Objective. This study planned to assess the heart rate dynamics in young obese subjects by nonlinear metrics to heart rate variability. Method. 86 subjects were split equally according to status. Heart rate was recorded with the subjects resting in a dorsal (prone) position for 30 minutes. The complexity of the RR-intervals was assessed by five Entropies, Detrended Fluctuation Analysis, Higuchi and Katz’s fractal dimensions Following inconclusive tests of normality we calculated the One-Way Analysis of Variance, Kruskal-Wallis, and the Effect Sizes by Cohen’s d significances. Results. It was established that Shannon, Renyi and Tsallis Entropies and the Higuchi and Katz’s fractal dimensions could significantly discriminate the two groups. The three entropies were higher in obese youths, suggesting less predictable sets of RR intervals (p<0.0001; d≈1.0). Whilst the Higuchi (p<0.003; d≈0.76) and Katz’s (p≈0.02; d≈0.57) fractal dimensions were lower in obese youths. Conclusion. As with chaotic globals an increase in response was detected by three measures of entropy in young obese. This is counter to the decreasing response detected by fractal dimensions. Chaotic globals and entropies are more dependable than fractal dimensions when assessing the responses to obesity

    Characteristics of sports injuries and factors associated with injury in beginners of female artistic gymnastics

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    La gimnasia artística es una modalidad que combina arte y gestos biomecánicos, y es destacada entre niños y adolescentes. Su práctica puede conducir a lesiones deportivas, por eso es importante conocer los factores inherentes al traumatismo para la formulación de modelos preventivos. De ese modo, el objetivo de este estudio es caracterizar las lesiones deportivas y verificar los factores asociados con lesión en practicantes de gimnasia artística de diferentes niveles de competitividad. Fueron entrevistadas 46 gimnastas, con edad media de 10,1±2,0 años de sexo femenino, clasificadas en dos niveles competitivos: iniciación y entrenamiento. Se utilizó la encuesta de morbilidad adaptada a las características de este deporte para recabar datos personales, de entrenamiento y de lesión. Fueron observadas 0,3 lesiones por atleta y 1,4 lesiones por atleta lesionado, en que gimnastas de la categoría de entrenamiento presentaron mayor frecuencia de lesión (83,3%; n=10) comparadas con las de iniciación (10,5%, n=4). Para ambos niveles, el momento de entrenamiento y la gravedad leve fueron los más relatados. En cuanto al mecanismo, el sin contacto fue el más prevalente en la categoría de entrenamiento (90%; n=9) y de contacto directo fue el más frecuente en la iniciación (75%; n=3). Las variables antropométricas y de entrenamiento fueron consideradas factores asociados con lesión para las gimnastas. Se concluye que las gimnastas de la categoría de entrenamiento poseen mayor frecuencia de lesión. Las variables antropométricas y de entrenamiento fueron factores asociados con lesión. Las características de las lesiones dependen del nivel de competitividad de las gimnastas.A ginástica artística é uma modalidade que combina arte a gestos biomecânicos e tem se destacado entre crianças e adolescentes. Sua prática pode conduzir a lesões desportivas, por isso é importante conhecer os fatores inerentes ao traumatismo para formulação de modelos preventivos. Desse modo, objetivou-se caracterizar as lesões desportivas e verificar os fatores associados com lesão em praticantes de ginástica artística de diferentes níveis de competitividade. Foram entrevistadas 46 ginastas, com média de idade de 10,1±2,0 anos do sexo feminino, classificadas em dois níveis competitivos: iniciação e treinamento. Utilizou-se o inquérito de morbidade referida adaptado com as características da modalidade para reunir dados pessoais, de treinamento e da lesão. Foram observadas 0,3 lesões por atleta e 1,4 lesões por atleta lesionado, em que ginastas da categoria de treinamento apresentaram maior frequência de lesão (83,3%; n=10) do que as de iniciação (10,5%; n=4). Para ambos os níveis, o momento treinamento e a gravidade leve foram os mais relatados. No mecanismo, o sem contato foi mais prevalente na categoria de treinamento (90%; n=9) e o contato direto foi o mais frequente na iniciação (75%; n=3). As variáveis antropométricas e de treinamento foram consideradas fatores associados com lesão para as ginastas. Conclui-se que ginastas da categoria de treinamento possuem maior frequência de lesão. As variáveis antropométricas e de treinamento foram fatores associados com lesão. As características das lesões dependem do nível de competitividade das ginastas.The artistic gymnastics is a modality that associates arts with biomechanical gestures, and it has been prominent among children and adolescents. Its practice can lead to sports injuries; therefore, it is important to know the factors inherent to trauma for the formulation of preventive models. Thus, the objective of this study was to characterize sports injuries and to verify factors associated with injury in people practicing artistic gymnastics with different levels of competitiveness. Forty-six gymnasts were interviewed with mean age of 10.1±2.0 years for female participants, who were classified in two competitive levels, i.e, initiation and training. We used the morbidity questionnaire adapted to sports characteristics to collect personal, training, and injury data. It was observed that injury risk was 0.3 injuries per athlete and 1.4 injuries per injured athlete, in which the gymnasts of the training category showed a higher frequency of the injury (83.3%; n=10) compared with the ones in the initiation category (10.5%; n=4). For both levels of competitiveness, training moment and light severity were the most reported variables. In the mechanism, contactless was more prevalent in the training category (90%; n=9) and the direct contact was more common at initiation category (75%; n=3). Anthropometric and training variables were considered as factors associated with injury to the gymnasts. It is concluded that gymnasts of the training category have higher injury frequency. Anthropometric and training variables were factors associated with injury. Characteristics of the injuries depend on the competitiveness level of the ­gymnasts

    RISK APPRAISAL BY NOVEL CHAOTIC GLOBALS TO HRV IN SUBJECTS WITH MALNUTRITION

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    The aim of this study is to assess the risk of dynamical diseases in malnourished children. This is achieved by the application of novel chaotic global techniques to the RR-intervals of the electrocardiogram (ECG) in the cohort. Heart Rate Variability (HRV) is an inexpensive and non-invasive tool to measure the autonomic impulses. Here there has been a decrease in chaotic response of HRV. Seventy children were divided into equal groups and the HRV monitored for 20-25 minutes. The Chaos Forward Parameter (CFP) which applies all three chaotic global parameters is suggested to be the most robust algorithm. These three parameters are high spectral entropy (hsEntropy), high spectral detrended fluctuation analysis (hsDFA) and spectral multi-taper method (sMTM). hsEntropy is a function of the irregularity of amplitude and frequency of the power spectrums peaks. It is derived by applying Shannon entropy to the multi-taper method power spectrum. To derive hsDFA we calculate the spectral adaptation in exactly the same way as for hsEntropy using an adaptive multi-taper method power spectrum with the same settings; but DFA rather than Shannon entropy is the algorithm applied. sMTM is the area between the multi-taper method power spectrum and the baseline. After Anderson-Darling and Lilliefors tests of normality; Kruskal-Wallis was used for the statistical analysis, with the level of significance set at (p &lt; 0.01). Principal Component Analysis (PCA) identified two components representing 100% of total variance. Autonomic imbalance measured as HRV and an increased cardiovascular risk are described for overweight children as well as for malnourished and those with anorexia nervosa. The relationship between malnourishment and complexity measures is useful in the risk assessment of dynamical diseases associated with the condition. This is supportive in treatments, assisting the determination of the level of dietary or pharmacological intervention especially in related dynamical diseases

    Sports Injuries and Their Risk Factors in Adolescents who Practice Swimming

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    Introdução: a natação é uma modalidade popular entre os adolescentes, no entanto, sua prática pode conduzir às lesões. Objetivos: caracterizar as lesões desportivas e associá-las com fatores de risco em adolescentes praticantes de natação de diferentes níveis de competitividade. Método: foram entrevistados 251 nadadores, com média de idade de 12,43±2,10 anos, ambos os sexos, recrutados ao acaso, classificadas em três níveis competitivos: categoria de iniciação, aperfeiçoamento e treinamento. Foi utilizado o inquérito de morbidade referida adaptado com as características da natação como instrumento de coleta que continha informações pessoais e de treinamento dos voluntários, como: idade, variáveis antropométricas e variáveis de treinamento e informações referentes às lesões ocorridas durante 12 meses. Todas as conclusões foram descritas no nível de 5% de significância. Resultados: Foram observadas 0,11 lesões por atleta e 1,03 lesões por atleta lesionado. Foi constatada associação entre presença e ausência de lesão com a variável estatura e tempo de treinamento. O mecanismo causal mais frequente foi o sem contato para as categorias de iniciação e treinamento. Os locais anatômicos mais acometidos foram os MMII e MMSS para todos os níveis de competitividade, assim como a gravidade leve, o treinamento e a ausência de recidiva predominaram. O retorno assintomático foi mais frequente para a iniciação, enquanto que o retorno sintomático prevaleceu na categoria de treinamento. Conclusão: a taxa de lesão nos adolescentes nadadores foi baixa. As variáveis estatura e tempo de treinamento foram associadas à ocorrência dos agravos. As características das lesões dependeram do nível de competitividade dos nadadores.Introduction: swimming is a popular sport among adolescents; however, your practice can lead to injuries. Objectives: to characterize the sport injuries and associate them with risk factors in teenage swimmers from different levels of competitiveness. Methods: 251 swimmers were interviewed, it an average age of 12.43±2.10, both sexes, recruited randomly and they were classified into three competitive levels: initiation, development, and training category. It wasused the morbidity survey adapted to the characteristics of swimming as collection instrument containing personal and training of volunteers data, as age, anthropometric variables and training variables and information relating to injuries sustained during a period of 12 months. All findings were described at the 5% significance level. Results: It was verified that there is an associationbetween the presence and absence of injury with the variable height and variable time. The causal mechanism most common was the non-contact mechanism for the categories of initiation and training. The most affected anatomical site was the lower limb and upper limb for all competitive levels. The mild severity, the training time and the absence of recurrence predominated. The asymptomatic return was more frequent for initiation, whereas the symptomatic return prevailed in the training category. Conclusion: the injury rate in teenage swimmers was low. The variables height and training time were associated with the occurrence of injuries. The characteristics of the injuries depended on the competitive level of the swimmers

    Analysis of cardiac autonomic modulation in obese and eutrophic children

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    INTRODUCTION: Obesity causes alterations in cardiac autonomic function. However, there are scarce and conflicting data on this function with regard to heart rate variability in obese children. OBJECTIVE: To compare the autonomic function of obese and eutrophic children by analyzing heart rate variability. METHODS: One hundred twenty-one children (57 male and 64 female) aged 8 to 12 years were distributed into two groups based on nutritional status [obese (n = 56) and eutrophic (ideal weight range; n = 65) according to the body mass index reference for gender and age]. For the analysis of heart rate variability, heart rates were recorded beat by beat as the children rested in the dorsal (prone) position for 20 minutes. Heart rate variability analysis was carried out using linear approaches in the domains of frequency and time. Either Student's t-test or the Mann-Whitney U-test was applied to compare variables between groups. Statistical significance was set at 5%. RESULTS: The SDNN, RMSSD, pNN50, SD1, SD2, LF and HF indices in milliseconds squared were lower among the obese children when compared to the eutrophic group. There were no alterations in the SD1/SD2 ratio, LF/HF ratio, LF index or HF index in normalized units. There was a significant difference between groups in the RR interval (R-to-R EKG interval). CONCLUSION: The obese children exhibited modifications in heart rate variability, characterized by a reduction in both sympathetic and parasympathetic activity. These findings stress the need for the early holistic care of obese children to avoid future complications

    Soil apparent electrical conductivity and geographically weighted regression for mapping soil

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    To resolve the spatial variation in soil properties intensively is expensive, but such knowledge is essential to manage the soil better and to achieve greater economic and environmental benefits. The objective of this study was to determine whether the soil apparent electrical conductivity (ECa), alone or combined with other variables, is a useful alternative for providing detailed information on the soil in the Extremadura region of Spain. Apparent soil electrical conductivity was measured and geographically weighted regression was used to characterize the spatial variation in soil properties, which in turn can be used for soil management. This study shows that soil cation exchange capacity, calcium content, clay percentage and pH have a relatively strong spatial correlation with ECa in the soil of the study area

    Influence of diabetes on autonomic function in children: analysis through the geometr ic indices

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    Introduction: Diabetes mellitus type 1 has been established as one of the most common noncommunicable diseases among children, diabetic autonomic dysfunction presenting as one of its most frequent complications, however, few studies have evaluated autonomic modulation through heart rate variability in diabetic children. Objective: To analyze the autonomic modulation in children with diabetes mellitus type 1. Methods: Data from 36 children of both sexes were analyzed, who were divided into two groups: Diabetes mellitus type 1, n = 13 (11.62 ± 2.18) with a diagnosis of Diabetes mellitus type 1 and control, n = 23 (11.04 ± 1.02) without the disease. Initially personal data, weight, height, heart rate and blood pressure were collected. Subsequently, for the analysis of autonomic modulation, the heart rate beatto-beat was captured using a heart rate monitor in the supine position for 30 minutes. The geometric indices (RRtri, TINN, Poincaré plot) were calculated to analyze autonomic modulation. The Student t test for parametric data or the Mann-Whitney test for nonparametric data, with a 5% signifi cance level, were used for comparison between groups. Results: The results demonstrated a reduction in RRtri, TINN, SD1 and SD2 in diabetic children. The SD1/SD2 ratio was similar between groups. In the qualitative analysis of the Poincaré plot, the children with Diabetes mellitus type 1 presented a fi gure with less dispersion of the points when compared to the control children. Conclusion: Children with diabetes mellitus type 1 have reduced overall variability and parasympathetic modulation
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