Abstract Objective: The purpose of this study was to investigate the effects of different intervals between static stretching for hip adductor, quadriceps and hamstring muscles and resistance training in repetition performance. Method: Twenty-two trained men were submitted to the 10 repetition maximum test and retest for leg extension, leg curl and hip adduction exercises. Three protocols were conducted in a randomized design - PWI: resistance training immediately after static stretching; P15: fifteen-minute rest interval between static stretching and resistance training; P30: thirty-minute rest interval between static stretching and resistance training. Results: The total number of repetition [(sets*repetitions) + exercises] performed under P30 (84.55 ± 1.68) was significantly higher than P15 (79.73 ± 1.89) and PWI (68.09 ± 2.03), respectively. Significant differences were also found between P15 and P30. Conclusions: Therefore, 30-minute interval between static stretching and resistance exercises was needed to achieve greater repetition performance. Thus, static stretching for lower limbs may be avoided before a resistance training session.

Resumo Objetivo: O objetivo deste estudo foi investigar os efeitos de diferentes intervalos entre alongamento estático para os músculos adutores do quadril, quadríceps e isquiotibiais e o treinamento resistido no desempenho de repetições. Método: Vinte e dois homens treinados foram submetidos ao teste de 10 repetições máximas e reteste para os exercícios de extensão, e flexão de joelhos, e de adução do quadril. Três protocolos foram conduzidos em um desenho randomizado: PWI - treinamento resistido imediatamente após o alongamento estático; P15 - intervalo de descanso de 15 minutos entre alongamento estático e o treinamento resistido; P30 - intervalo de descanso de 30 minutos entre alongamento estático e o treinamento resistido. Resultados: O número total de repetição ([séries * repetições] + exercícios) realizada em P30 (84.55 ± 1.68) foi significativamente maior do que o P15 (79.73 ± 1.89) e PWI (68.09 ± 2.03), respectivamente. Diferenças significativas também foram encontradas entre P15 e P30. Conclusões: O intervalo de 30 minutos entre o alongamento estático e o exercício resistido foi necessário para alcançar maior desempenho no número de repetição. Assim, os alongamentos estáticos para membros inferiores podem ser evitados antes de uma sessão treinamento resistido.

Resumen Objetivo: El objetivo de ese estudio fue investigar los efectos de distintas secuencias de estiramiento estático, en los músculos aductores de la cadera, cuádriceps e isquiotibiales y el entrenamiento de resistencia, en el rendimiento en repeticiones. Método: Veintidós hombres entrenados fueron sometidos a la prueba de 10 repeticiones máximas para ejercicios de extensión de piernas, flexión de piernas y aducción de cadera. Tres protocolos fueron realizados utilizando un diseño aleatorio: PSI: entrenamiento de resistencia realizado inmediatamente después del estiramiento estático; P15: intervalo de descanso de 15 minutos entre estiramiento estático y entrenamiento de resistencia; P30: intervalo de descanso de 30 minutos entre estiramiento estático y entrenamiento de resistencia. Resultados: El número total de repeticiones [(sets*repetición) + ejercicio], realizadas en P30 (84.55 ± 1.68) fue significativamente mayor que P15 (79.73 ± 1.89) y PSI (68.09 ± 2.03), respectivamente. También se observaron grandes diferencias entre P15 y P30. Conclusiones: Por lo tanto, se necesitó un intervalo de 30 minutos entre el estiramiento estático y los ejercicios de resistencia para lograr un mayor rendimiento en repeticiones. En este sentido, el estiramiento estático para miembros inferiores puede ser evitado antes de una sesión de entrenamiento de resistencia.

Bone formation around a metallic implant is a complex process that involves micro- and nanometric interactions. Several surface treatments, including coatings were developed in order to obtain faster osseointegration. To understand the role of these surface treatments on bone formation it is necessary to choose adequate characterization techniques. Among them, we have selected electron microscopy, profilometry, atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS) to describe them briefly. Examples of the potentialities of these techniques on the characterization of titanium for biomedical applications were also presented and discussed. Unfortunately more than one technique is usually necessary to describe conveniently the topography (scanning electron microsocopy, profilometry and/or AFM) and the chemical state (XPS) of the external layer of the material surface. The employment of the techniques above described can be useful especially for the development of new materials or products.

Low-temperature plasma treatment has been used in the last years as a useful tool to modify the surface properties of different materials, in special of polymers. In the present work low temperature plasma was used to treat the surface of asymmetric porous substrates of polysulfone (PSf) membranes. The main purpose of this work was to study the influence of the exposure time and the power supplied to argon plasma on the permeability properties of the membranes. Three rf power levels, respectively 5, 10 and 15 W were used. Treatment time ranged from 1 to 50 min. Reduction of single gas permeability was observed with Ar plasma treatments at low energy bombardment (5 W) and short exposure time (20 min). Higher power and/or higher plasma exposition time causes a degradation process begins. The chemical and structural characterization of the membranes before and after the surface modification was done by AFM, SEM and XPS.