Flávia Porto

Transcranial direct current stimulation influences the cardiac autonomic nervous control

To investigate whether the manipulation of brain excitability by transcranial direct current stimulation (tDCS) modulates the heart rate variability (HRV), the effect of tDCS applied at rest on the left temporal lobe in athletes (AG) and non-athletes (NAG) was evaluated. The HRV parameters (natural logarithms of LF, HF, and LF/HF) was assessed in 20 healthy men before, and immediately after tDCS and sham stimulation. After anodal tDCS in AG the parasympathetic activity (HF(log)) increased (P<0.01) and the sympathetic activity (LF(log)) and sympatho-vagal balance (LF/HF(log)) decreased (P<0.01), whereas no significant effects were detected in NAG (P>0.05). No significant changes in HRV indexes were provoked by sham stimulation in both AG and NAG (P>0.05). In conclusion, tDCS applied on the left temporal lobe significantly increased the overall HRV in AG, enhancing the parasympathetic and decreasing the sympathetic modulation of heart rate. Consequently the sympatho-vagal balance decreased at rest in AG but not in NAG. Releasing a weak electric current to stimulate selected brain areas may induce favorable effects on the autonomic control to the heart in highly fit subjects.

Moiré topography: characteristics and clinical application.

Since 1970, the Moiré phenomenon has been employed as a method of clinical diagnosis in topographical analyses of the human body. The objective of this study was to review the literature on the main characteristics of the Moiré phenomenon and its use as a topographical method for clinical applications, particularly those related to postural deviations. A systematic search for papers written in English between 1966 and 2010 was performed according to pre-established selection criteria and the selected studies underwent a content analysis. The results showed an evolution in the method of Moiré topography (MT), which reflect an increasing effort to improve the accuracy and precision of the method, as well as to facilitate the interpretation of topograms using specific software. The Shadow and Projection Moiré techniques have more frequently been used in comparison with other techniques. On the other hand, the methodological procedures of MT are apparently not well defined in the literature. Although MT was shown to be useful in the detection of spinal deformities, there is still a lack of research in clinical settings, especially in the elderly. For the most part, the studies involve the tracking of scoliosis in school age children. Japan appears to be the most advanced country in terms of the application of MT.

Motor cortex tDCS does not improve strength performance in healthy subjects

La influencia de estimulacion transcraneal de corriente directa (tDCS) en ejercicios de fuerza muscular de rendimiento que reclutan grandes masas musculares no se ha establecido en la poblacion sana. El objetivo de este estudio fue investigar si la ETCC anodica podria mejorar el rendimiento durante el ejercicio maximo de la fuerza (EMF) en sujetos sanos. Catorce voluntarios (26 ± 4 anos de edad) realizaron dos EMF con la aplicacion previa de ETCC anodica y placebo (2 mA, 20 i) la participacion de los flexores y extensores de la rodilla dominante en accion concentrica (3 series de 10 repeticiones). La actividad electrica muscular (sEMG) en cuatro musculos reclutados se registro durante el EMF. La ETCC anodica no fue capaz de mejorar la potencia de salida (trabajo total y pico de torque), la resistencia a la fatiga o la actividad electromiografica durante el EMF, cuando comparada con la condicion placebo. Por lo tanto, la ETCC anodica aplicada a la corteza motora contralateral no fue capaz de aumentar el rendimiento de la fuerza de flexores y extensores de la rodilla en jovenes sanos.

Topografia de moiré como método de avaliação postural: revisão do estado da arte

Since 1970, the moire phenomenon has been employed as a method of clinical diagnosis in topographical analyses of the human body. As a postural evaluation method, the moire topography (MT) assists in the examination of postural deviations on frontal, sagittal and transversal planes, through the analysis of a single image (topogram) of the subjects backside. This study aimed to carry out a literature review whose approach included the main characteristics of the moire phenomenon and its use as a topographical method for clinical analyses, particularly those related to postural deviations. A literature survey of the main sources of international and national academic research was made and all the material collected from this survey then underwent a pre-established selection criteria and analysis. The results showed an evolution in the method of moire topography, that is, an increasing concern to improve the accuracy and precision of the method, as well as to facilitate the interpretations of the topograms by means of the use of softwares. It was mainly observed that the shadow and projection moire techniques were more used than the other techniques of moire. In addition to this, it was apparent that the methodological procedures of moire topography are not well defined in literature. Although MT has shown to be very useful in the detection of vertebral column deformities, it was verified that there exists a great lack of studies that have applied this technique to clinically evaluate adults and the elderly. The majority of studies involve the tracking of scoliosis in school age children, because it is a public health issue.

Influence of the length of institutionalization on older adults' postural balance and risk of falls: a transversal study

OBJETIVO: verificar a influencia do tempo de institucionalizacao no equilibrio e no risco de quedas de idosos. METODO: para a avaliacao do risco de quedas utilizaram-se o Berg Balance Scale e o Get Up and Go e, para a medida do equilibrio postural, foi utilizada a estabilometria estatica com aquisicao da area eliptica de 95% e velocidades medias nos eixos x e y do deslocamento do centro de pressao. Foram empregadas medidas de associacao e comparacao parametricas e nao parametricas (α<0,05). RESULTADOS: nao houve correlacao significativa entre o tempo de institucionalizacao e os testes de avaliacao do risco de quedas, como tambem nao houve diferenca intergrupos e intrassubgrupos, estratificados por tempo de institucionalizacao e idade. Nas medidas estabilometricas, houve correlacao negativa entre os parâmetros analisados e o tempo de institucionalizacao, e diferenca intergrupos e intrassubgrupos. CONCLUSAO: os resultados desta pesquisa apontam a dificuldade de execucao das tarefas de controle postural, mostrando um nivelamento abaixo dos escores de referencia dos testes clinicos. No comportamento estabilometrico, adverte-se reducao dos parâmetros conforme aumenta o tempo de institucionalizacao, contrariando as suposicoes. Os resultados deste estudo poderao oferecer subsidios para a elaboracao de um modelo multiprofissional de intervencao sobre o controle postural e o equilibrio dos idosos residentes em instituicoes de longa permanencia para idosos.

O exercício físico influencia a postura corporal de idosas

Age-associated postural changes directly affect daily-task performance. Exercise has been used in order prevent impairments caused by aging process. This study has aimed to compare the postural profile at the sagittal plane of elderly women participants of the Multidimensional Study of Elderly in Porto Alegre (EMIPOA) and elderly women engaged in an exercise program (GEF) through posture grad assessment. Posterior image analysis and posture classification was done as described by Kendall, Mccreary e Provance (1995). We used descriptive statistics and the Kolmogorov-Smirnov test (α<0.05) to compare the results of the groups. Both groups presented the kyphosis-lordosis as predominant posture profile. There was no significant difference in prevalence of postural profile between EMIPOA and GEF. Results suggest that the exercise program was not effective to produce postural changes at the sagittal plane for elderly women.

Influence of breathing patterns and orthostatic stress on postural control in older adults: Breathing patterns and postural control

To investigate the influence of breathing patterns and blood pressure behavior postural control in older adults.

Correction: Physiological responses and external validity of a new setting for taekwondo combat simulation

[This corrects the article DOI: 10.1371/journal.pone.0171553.].

Shadow Moiré technique for postural assessment: qualitative assessment protocol by intra- and inter-rater evaluation

[Purpose] This study aimed to develop and validate an assessment tool for Moiré topogram made specifically with the Shadow Moiré technique of the dorsum. [Subjects and Methods] In the analysis of topograms, frontal, sagittal, and transverse planes of individuals’ dorsal were considered. Two instructor evaluators analyzed the topograms at different times in the day and on different days. The measurements of intra- and inter- (intra- and interday) reliability were calculated. [Results] Of the three planes analyzed, in all analyses, good (0.61 to 0.80) and/or excellent (0.81 to 1) concordances were observed. [Conclusion] This analysis framework can be recommended to evaluate the topograms obtained with SMT.

ETCC sobre o córtex motor não aumenta o desempenho de força em sujeitos saudáveis

La influencia de estimulacion transcraneal de corriente directa (tDCS) en ejercicios de fuerza muscular de rendimiento que reclutan grandes masas musculares no se ha establecido en la poblacion sana. El objetivo de este estudio fue investigar si la ETCC anodica podria mejorar el rendimiento durante el ejercicio maximo de la fuerza (EMF) en sujetos sanos. Catorce voluntarios (26 ± 4 anos de edad) realizaron dos EMF con la aplicacion previa de ETCC anodica y placebo (2 mA, 20 i) la participacion de los flexores y extensores de la rodilla dominante en accion concentrica (3 series de 10 repeticiones). La actividad electrica muscular (sEMG) en cuatro musculos reclutados se registro durante el EMF. La ETCC anodica no fue capaz de mejorar la potencia de salida (trabajo total y pico de torque), la resistencia a la fatiga o la actividad electromiografica durante el EMF, cuando comparada con la condicion placebo. Por lo tanto, la ETCC anodica aplicada a la corteza motora contralateral no fue capaz de aumentar el rendimiento de la fuerza de flexores y extensores de la rodilla en jovenes sanos.