Abstract This study evaluated the eradication of eucalyptus sprouts after chemical weeding using a diagrammatic scale over time. The research was conducted in fields planted with eucalyptus in forest reform areas, in Itabela, Bahia, Brazil, during the pre-planting herbicide application. The application was carried out in five fields, which were considered as sample units of the different treatments. The effectiveness of chemical weeding for controlling sprout growth was evaluated in fifty plants per treatment, randomly selected in three periods after application. The plants were evaluated visually using a diagrammatic scale to assign scores between 1 and 5 to the sprout control percentage. After the visual evaluations, the frequency distribution of the sprouting percentage for each score was calculated. Subsequently, the scores were submitted to a clustering analysis by the Ward method, to evaluate the relationship between different fields and periods for each treatment in homogeneous clusters. The results showed that treatments only controlled the sprouts in the short term, without providing effective eradication. The diagrammatic scoring scale allowed evaluating the vegetative vigor of the eucalyptus sprouts, generating interpretable information on the different evaluated treatments, making it a useful tool for managing silvicultural treatments and evaluating the application efficacy of phytosanitary products.

Abstract The aim of this study was to evaluate spatial behavior and temporal stability of rainfall and mean air temperature in the state of Bahia, using historical series from 1975 to 2011 and 1961 to 2009, respectively. The analyses were performed considering the accumulated variables of each month of the historical series. The accumulated monthly totals were divided by the number of years of observation, obtaining the monthly average values of rainfall and air temperature for each measurement point. The data were submitted to descriptive statistical analysis and linear correlation studies. Geostatistical analysis was used to verify the existence and quantify spatial dependence between the values of the studied variables. In addition, the maps were submitted to algebra operations, calculating the spatial difference between months for each of the variables. For that purpose, the difference between one month and its subsequent period was calculated in order to establish the behavior of the variables over time. Climatic variables showed a close relationship between each other, demonstrating their spatial and temporal variation, which is mainly dependent on the seasons of the year. The rainfall and mean air temperature variables showed stable spatial behavior and high temporal stability between subsequent months.

"Adaptações neurais em contrações isométricas com biofeedback EMG e de força." Este estudo avaliou as adaptações neurais do quadríceps durante contrações isométricas usando os sinais de força e eletromiografia (EMG) como biofeedback. Quarenta e dois sujeitos foram distribuídos em três grupos: EMG, testado com biofeedback da EMG; Força, testado com biofeedback de força; e Controle, testado sem biofeedback. As avaliações foram realizadas pré/pós-testes para determinar a máxima força e amplitude EMG durante contrações isométricas voluntárias máximas (CIVM). Os testes consistiram em séries de CIVM onde os sujeitos foram encorajados a ultrapassar os limiares de força e EMG inicialmente determinados. A amplitude EMG do vasto lateral e a força extensora do joelho aumentaram significativamente em todos os grupos quando comparadas as avaliações pré e pós-testes (p < 0,05). A porcentagem de ganho EMG foi significativamente diferente entre os grupos Força e Controle (p < 0,01), enquanto que a porcentagem de ganho da força não foi diferente entre os grupos. O biofeedback de força foi mais efetivo em produzir adaptações neurais.

This study aimed to evaluate the quadriceps femoris neural adaptations during isometric contractions using force and electromyogram (EMG) signals as visual biofeedback. Forty-two participants were randomly assigned to three groups: EMG group, tested with EMG biofeedback; Force group, tested with force biofeedback; and Control group, tested without biofeedback. Evaluations were performed pre (baseline) and post-tests to determine the maximum force and EMG amplitude during maximal voluntary isometric contraction (MVIC). The tests consisted of series of MVICs in which the participants were encouraged to surpass the force or EMG thresholds determined at baseline. The vastus lateralis EMG amplitude and knee extensor force increased significantly in all groups when compared the baseline and post-test evaluations values (p < .05). EMG percentage gain was significantly different between Force and Control groups (p < .01), while force percentage gain was not different between groups. Force biofeedback was more effective in producing neural adaptations.

"Adaptaciones neurales en contracciones isométricas con biofeedback EMG e de fuerza." Este estudio evaluó las adaptaciones neurales de cuádriceps durante contracciones isométricas usando los signos de fuerza y electromiografía (EMG) como biofeedback. Cuarenta y dos sujetos fueron divididos en tres grupos: EMG, probado con biofeedback EMG; Fuerza, probado con biofeedback de fuerza; y control, probado sin biofeedback. Las avaluaciones se realizaron pre/post pruebas para determinar la máxima fuerza y amplitud EMG durante contracciones isométricas voluntarias máximas (CIVM). Las pruebas consistieron en series de CIVM en que los sujetos fueron encorajados a cruzar el umbral de fuerza y EMG inicialmente determinados. La amplitud EMG del vasto lateral y fuerza de los extensores de la rodilla aumentó significativamente en todos los grupos al comparar las avaluaciones pre y post pruebas (p < 0,05). El porcentaje de ganancia EMG fue significativamente diferente entre los grupos Fuerza y control (p < 0,01), mientras que el porcentaje de aumento de la fuerza no fue diferente entre los grupos. Biofeedback de fuerza fue más eficaz en producir adaptaciones neurales.

INTRODUÇÃO: Estudos da condução nervosa têm sido focados para o público em geral, porém não para atletas, havendo carência de informações sobre medidas da velocidade de condução nervosa motora (VCNM) em indivíduos treinados, especialmente quando diferentes esportes são comparados. OBJETIVO: Medir a VCNM do nervo mediano e fibular comum, em três grupos de modalidades esportivas. Métodos: Foram analisados: um grupo de meio-fundistas (Gmf, n = 6), um grupo de velocistas (Gvel, n = 4) e um grupo de jogadores de handebol (Ghan, n = 5) e comparados com um grupo controle (Gcon, n = 9). Cada voluntário foi submetido a um único exame, no qual foram obtidos os dados para calcular a VCNM dos membros inferiores do Gmf e do Gvel, dos membros superiores do Ghan, e membros superiores e inferiores do Gcon. Os dados da pesquisa apresentaram distribuição normal e variâncias homogêneas, assim, utilizamos o teste t de Student para amostras independentes na comparação das médias da VCNM dos grupos de atletas com as do Gcon e as do Gvel com as do Gmf (comparações intergrupo). O teste t pareado foi usado para comparar as médias da VCNM entre membro dominante (Md) e membro não dominante (Mnd) (comparações intragrupo). RESULTADOS: Na análise intergrupo foram encontradas diferenças significativas nas comparações entre o Gvel e o Gcon e entre o Gmf e o Gcon (diferença apenas nas comparações entre os Md's). Por outro lado, a análise intragrupo, exibiu diferença significativa apenas nas comparações entre Md e Mnd do Ghan. CONCLUSÃO: O estudo sugere que a VCNM é beneficiada pelo esforço físico, principalmente em esportes com uso predominante dos membros inferiores, e que a maior utilização de um membro superior sobre outro pode levar a diferença significativa nos valores da VCNM do Md e Mnd.

INTRODUCTION: Electrodiagnostic tests such as nervous conduction studies are mainly aimed at the general public, not at athletes. Therefore, information about motor nervous conduction velocity (MNCV) is scarce for trained subjects, especially when different sports are compared. OBJECTIVE: to measure the MNCV of the median and common fibular nerves in three groups of sport modalities. Methods: A group of middle distance runners (M RG, n=6), a group of sprinter runners (S RG, n=4) and a group of handball players (H G, n=5) were analyzed and compared to a control group (C G, n=9). Each volunteer was submitted to a single examination where data necessary to measure MNCV from the lower limbs of M RG and of S RG; upper limbs of H G and both upper and lower limbs of C G were collected. Data analysis presented normal distribution and homogeneous variances in all cases; therefore, a Student's t test for independent samples was used to compare means of MNCV of the athlete groups and the C G, as well as in the mean comparison of S RG and M RG (intergroup comparison). The paired Student's t test was used to compare MNCV means of the dominant limb (DL) and non-dominant limb (NDL) (intragroup comparison). RESULTS: Significant differences were found in the comparison between S RG and CG and between M RG and CG, but only in the DL comparison in the last case. On the other hand, in the intragroup comparison, there was significant difference only in the comparison between D L and N DL of the H G. CONCLUSION: This study suggests that MNCV benefits from physical exercise, especially in those sports where lower limbs are predominantly used. It also suggests that greater use of one upper limb over the other could lead to significant differences in MNCV values of D L and N DL.

A suplementação de creatina apresenta ação ergogênica na força muscular. Entretanto, não há consenso deste efeito na força isométrica máxima e na amplitude do eletromiograma (EMG). Assim, o objetivo deste estudo foi analisar os efeitos da suplementação de creatina na força isométrica máxima e na amplitude do EMG em mulheres fisicamente ativas. Vinte e sete mulheres (idade 23,04 ± 1,82 anos, massa corporal 58,37 ± 6,10kg, estatura 1,63 ± 0,05m e índice de massa corporal 21,93 ± 2,02kg/m²) foram designadas aleatoriamente para os grupos creatina (GCr) (n = 13) e placebo (GPL) (n = 14), os quais ingeriram diariamente, durante seis dias, 20g de creatina mono-hidratada e 20g de maltodextrina, respectivamente. Antes e depois da suplementação, a força foi medida em um dinamômetro isométrico durante contração isométrica voluntária máxima (CIVM) de extensão unilateral do joelho (três séries de 6s intervaladas por 180s), com captação simultânea dos valores root mean square (RMS) do EMG obtido no músculo vasto lateral. A ANOVA de dois critérios de classificação (dois momentos x dois grupos) e o teste de Wilcoxon foram utilizados na análise estatística dos dados paramétricos e não paramétricos (p < 0,05). Após a suplementação, o GCr aumentou significativamente a força, com incrementos de 7,85% (p = 0,002), 7,31% (p = 0,001) e 5,52% (p = 0,001) para a primeira, segunda e terceira séries, respectivamente. Para este mesmo grupo, os valores RMS aumentaram significativamente na terceira série (p = 0,026). O GPL não apresentou alterações significativas. Os resultados sugerem que a suplementação de creatina aumenta a força isométrica máxima e que a amplitude do EMG pode ser utilizada como indicador dessas alterações de desempenho.

Creatine supplementation has shown to enhance muscular strength. However, there is not a consensus on this effect on maximal isometric strength neither on electromyogram (EMG) amplitude. Thus, the aim of this study was to analyze the creatine supplementation effects on maximal isometric strength and EMG amplitude in physically active women. 27 women (age 23.04 ± 1.82 years, body mass 58.37 ± 6.10kg, height 1.63±0.05m and body mass index 21.93 ± 2.02kg/m²) were randomly assigned in creatine (CrG) (n = 13) or placebo group (PLG) (n = 14). The CrG and PLG ingested 20g/day of creatine and 20g/day of maltodextrin during six days, respectively. The strength was measured before and after supplementation using a isometric dynamometer during a maximal isometric voluntary contraction (MIVC) of a unilateral knee extension (3 sets of 6s with 180s rest period), and the EMG was acquired from the vastus lateralis muscle and its amplitude quantified using the root mean square (RMS) values. Two-way ANOVA (2 groups x 2 moments) was used for parametric data and Wilcoxon test for non-parametric analysis (p < 0.05). After supplementation, CrG significantly enhanced strength, with increase of 7.85% (p = 0.002); 7.31% (p = 0.001) and 5.52% (p = 0.000) for the first, second and third trials, respectively. In CrG, the RMS values significantly increased on the third trial (p = 0.026). No changes were found in GPL. Results suggest that creatine supplementation enhance maximal isometric strength and EMG amplitude can be useful to identify these performance modifications.