Recursos de colección

Biblioteca Digital do IPB (53.442 recursos)

A Biblioteca Digital do IPB, tem por objectivo divulgar e permitir o livre acesso à produção científica produzida pela comunidade académica, promovendo a integração, partilha e a visibilidade da informação científica e garantindo a preservação da memória intelectual do Instituto Politécnico de Bragança.

DCDEF - Comunicações em Encontros Científicos Indexadas ao ISI

Mostrando recursos 1 - 11 de 11

  1. Effects of eccentric exercise on force steadiness and activation of the knee extensors

    Vila-Chã, Carolina; Falla, Deborah; Farina, Dario
    AIM: The purpose of this study was to investigate the effects of eccentric exercise of the knee extensors on force steadiness and neural drive to the vasti muscles during submaximal isometric contractions. METHODS: Ten healthy subjects (age, mean ± SD, 24.9 ± 3.2 yrs) participated in the study. The subjects performed maximum voluntary contractions (MVC) of the knee extensors followed by isometric contractions at 2.5, 5, 10, 15, 20 and 30% MVC at baseline, immediately after and 24h after eccentric exercise of the quadriceps. During each contraction, force and surface EMG of the vastus medialis (VM), vastus lateralis (VL), biceps femoris...

  2. Morphologic and systemic alterations in obese and overweight subjects after a physical activity intervention program

    Magalhães, Pedro M.; Costa, M.J.; Lopes, Vítor P.; Duarte, José Alberto
    There are some evidences that exercise training reduces total and abdominal fat and some systemic variables with improve health benefits. The sim of this study was to ana1yse the variation of some morphologic and systemic variables in 16 (age-64.5±7.2) obese and overweight (BM!=31.4o±5.7) type 2 diabetic patieots, of hoth gender, dutiog a regular physical exercisc program, which consists of 3 5 minutes of fast walking every days of the week, during 8 months, and no diet intervention.

  3. Calibration of MTI actigraph in old obese adult

    Lopes, Vítor P.; Magalhães, Pedro M.; Bragada, José A.
    The purpose was to derive a regression equation that estimatcs energy expenditure from accelerometer counts in oId obese adult. The sample comprised 14 oId obese or overweight adults (63±7 years).

  4. Patterns of physical activity: an exploratory study using twins

    Maia, José A.R.; Lopes, Vítor P.; Martins, Sónia; Amorim, António; Alves, Cintia
    The study of physical activity patterns (PAP) is still in its infancy due to methodological problems in measuring instruments of physical activity, and the lack of specific analytical tools to capture all its intrinsic issues. Moreover, it is not well known if differences among subjects are mainly due to specific environmental conditions, genetic attributes or both. This picture is more acute in children. PURPOSE: to explore different ways of viewing and analyzing PAP in children. METHODS: 31 twin pairs (18 MZ and 13 DZ) aged 6 to 12 years of age were monitored for 5 days (3 week-day and a week-end) with a tri-axial accelerometer (TRITRAC R3D). Count...

  5. Familial aggregation of physical activity levels: a study with families from northeast of Portugal

    Lopes, Vítor P.; Vasques, Catarina; Maia, José A.R.

  6. Is front crawl swimming performance affected by hydrodynamic drag in young swimmers?

    Silva, A.J.; Marques, M.C.; Garrido, N.; Barbosa, Tiago M.; Costa, M.J.; Louro, H.; Reis, V.M.; Marinho, D.A.
    Swimming performance is affected by several factors including the hydrodynamic drag. Hydrodynamic drag is the force that a swimmer has to overcome in order to maintain his movement through water and is highly dependent on swimming technique. PURPOSE: To analyse in young swimmers the relationship between hydrodynamic drag and the front crawl performance. METHODS: 25 young swimmers (11 females and 14 males) participated in this study. Their mean (standard deviation) age, body mass, height and best swimming performance in 100 m front crawl was 12.08 (0.76) years, 43.08 (7.60) kg, 1.52 (0.08) m and, 75.11 (9.57) s, respectively

  7. A path-flow analysis model for active drag force determinant variables in age-group swimmers

    Barbosa, Tiago M.; Costa, M.J.; Marques, M.C.; Moreira, M.; Silva, A.J.; Marinho, D.A.
    The role of drag force in competitive swimming is one of the main topics for researchers and field practitioners as it allows enhancing performance. The development of “flow chart” models confirming the relationships between drag force and other determinant variables was never attempted in competitive swimming. Moreover, main research groups dedicate little attention to age-group swimming. PURPOSE: The aim was to develop a structural equation modeling (i.e., path-flow analysis model) for active drag force (Da) based on anthropometric, hydrodynamic and biomechanical determinants in young swimmers. The theoretical model was developed according to main review papers about these determinants. METHODS: Sixteen male swimmers (12.50±0.51 years-old; Tanner stages’ 1 -2) were evaluated. It was assessed:...

  8. The effect of depth on drag during the gliding phase in swimming

    Marinho, D.A.; Ribeiro, J.; Mantripragada, N.; Machado, L.; Vilas-Boas, J.P.; Fernandes, R.J.; Barbosa, Tiago M.; Rouboa, A.; Silva, A.J.
    The gliding phase following a swimming start or turn is an important component of the overall swimming performance. PURPOSE: To analyse the effect of depth on hydrodynamic drag force during the underwater gliding, using computational fluid dynamics. METHODS: A three-dimensional domain was created to simulate the fluid flow around a swimmer model, representing the geometry of part of a lane in a swimming pool. The water depth of this domain was 1.50 m with a 3.0 m width and 11.0 m length. Computational fluid dynamics methodology was used to perform numerical simulations in the created domain which was divided into a number of mesh cells. The k-epsilon turbulent model was applied...

  9. Modelling changes in gross motor coordination of portuguese children: effects of BMI and physical activity

    Maia, José A.R.; Coelho, Renata; Silva, R.; Seabra, André; Lopes, Vítor P.

  10. Waist circumference and motor coordination in Portuguese school children

    Lopes, Luís; Santos, Rute; Pereira, Beatriz; Lopes, Vítor P.
    Introduction: Children’s motor coordination may affect their activity pattern and thereby influence their body-fatness. The aim of this study was to analyze the relation between motor coordination and waist circumference (WC) levels, in a Portuguese sample of school children aged 8–12 years old. Methods: The sample comprised 402 urban school children (girls- 46.8%), aged 8 to 12 years old (mean 9.6 = ± 0.6 years) from North of Portugal. WC was measured with standardize protocols. Age- and sex-adjusted Z-scores were also computed for WC. Motor coordination levels were assessed with the Ko¨ rperkoordination Test fu¨ r Kinder (KTK) and children were classified according to age-and sex KTK criteria [1]. Results: In motor...

  11. A surgical training model manufacture using rapid prototyping technology

    Queijo, Luís; Rocha, João; Barreira, Luísa; Barbosa, Tiago M.; Pereira, Paulo Miguel; San Juan, Manuel
    The use of rapid prototyping has increasingly begun to reveal itself as a tool of great value in supporting medical activity. From two-dimensional medical images from computed tomography (CT) or magnetic resonance imaging (MRI) it is possible to obtain three-dimensional models. The models produced by rapid prototyping technologies are useful both in educational and medical-surgical environments. It can simplify the diagnosis of certain diseases, the development of complex surgical procedures, the prostheses and medical devices manufacture and the visualization of anatomical structures in educational environment.

Aviso de cookies: Usamos cookies propias y de terceros para mejorar nuestros servicios, para análisis estadístico y para mostrarle publicidad. Si continua navegando consideramos que acepta su uso en los términos establecidos en la Política de cookies.