Estudo Comparativo da flexão máxima da Articulação da Anca nas Variantes Formal e Natural da Técnica de Bruços

O nível técnico de adequação mecânica das variantes formal (bf) e natural (bn) da técnica de bruços constitui um importante pó­lo de interesse da biomecância da natação. Um dos argumentos mais frequentemente utilizados para a justificação da superioridade do bn é a menor flexão máxima da anca tida como característica desta va­riante. Neste trabalho é estudado o ângulo máximo de flexão da anca em cada uma das duas variantes da técnica de bruços. Foram analisa­das imagens subaquáticas de 8 nadadores, 5 do sexo masculino e 3 do sexo feminino, sendo 4 executantes de bf e 4 executantes de bn. Os valores médios dos ângulos de flexão maxima da anca obtidos para ca­da variante não foram significativamente diferentes (p< 0.05), ten­do, contrariamente à maioria dos valores referidos na literatura, sido inferior o nivel de flexão registrado para os executantes de bf

RECONSTRUCTION ERROR OF CALIBRATION VOLUME’S COORDINATES FOR 3D SWIMMING KINEMATICS

The aim of this study was to investigate the accuracy and reliability of above and underwater 3D reconstruction of a calibration volume used for swimming analysis. The calibration volume (3x2x3m3) was positioned half above and half below the water surface. Recordings with four underwater and two above water synchronised cameras were done and DLT algorithm used to estimate marker locations. Reconstruction accuracy was determined by the RMS error of 12 validation points and reliability by the standard deviation of all digitisations of the same marker. Comparison among different number of control points showed the set of 24 points to be the most accurate for both environments. Although, the RMS values above water were lower than the RMS values presented underwater. The calibration volume was found to have high accuracy and reliability

TECHNOLOGY FOR DECREASING ACTIVE DRAG AT THE MAXIMAL SWIMMING VELOCITY

The article describes the technology for decreasing active drag at the maximal swimming velocity. This technology can be used for both elite and sub-elite swimmers of different sex, age and qualification. It has been developed on the basis of optimal interaction between two functional systems of a swimmer (biomechanical and metabolic). The technology includes three components (training exercises; choice of training categories according to their international classification; use of special technical devices), as well as a set of concrete methods and technical procedures. The parameters, necessary for the research, have been measured by the method of small perturbations with the help of an additional hydrodynamic body

MEASUREMENT OF BUTTERFLY AVERAGE RESULTANT IMPULSE PER PHASE

The aim of this study was to measure the average resultant impulse (ARI) per phase of the stroke cycle in butterfly and to analyse the variability of ARI according to the adopted breathing technique. The sample was composed of 6 male Portuguese swimmers at national and international level. 6 cameras were set, obtaining non coplanar images (2 "dual media" images included). The study comprised the kinematical analysis of stroke cycles of the butterfly stroke using the "Ariel Performance Analysis System" from Ariel Dynamics Inc. and a VCR at a frequency of 50 Hz. The ARI was calculated using the mean horizontal acceleration of the cenler of mass in each phase, the absolute duration of each phase and the body mass of the swimmer. Comparing the ARI according to the breathing technique adopted in each phase of the stroke cycle, we only observed significant differences in the outsweep. Comparing the intra-cyclic variations of the ARI in the different breathing techniques adopted, the arm's recovery when compared with the remained phases presented a significantly lower ARI

Muscle activation behavior in a swimming exergame:Differences by experience and gaming velocity

International audienc

Do player performance, real sport experience, and gender affect movement patterns during equivalent exergame?

International audienc

Assessment of individual anaerobic threshold and stroking parameters in swimmers aged 10–11 years

info:eu-repo/semantics/publishedVersio

Anaerobic Threshold Individualized Assessment in a Young Swimmer

info:eu-repo/semantics/publishedVersio

FORCE AND CENTER OF PRESSURE EVALUATION WITH AN INSTRUMENTED PLATFORM FOR SWIMMING PERFORMANCE OPTIMIZATION

Start technique may consume an important amount of time in swimming events. Its optimization is the main target of a force platform design and implementation in order to bring benefits to coaching and to swimmer’s performance. Such a platform is being designed for technical performance evaluation of the start technique in elite swimmers and mimics the start block, namely fulfilling new FINA’s facilities rules. The purpose of this study is to present results of calibration procedures in order to define transfer function for determination and measurement of force and centre of pressure position in such an instrumented platform

Physiological demands of a swimming-based video game:Influence of gender, swimming background, and exergame experience

International audienc