Football player dominant region determined by a novel model based on instantaneous kinematics variables.

Dominant regions are defined as regions of the pitch where a player can reach before any other and are commonly determined without considering the free-spaces in the pitch. We presented an approach to football players' dominant regions analysis, based on movement models created from players' positions, displacement, velocity, and acceleration vectors. 109 Brazilian male professional football players were analysed during official matches, computing over 15 million positional data obtained by video-based tracking system.

Repercussion of medium and long treatment period with continuous positive airways pressure therapy in heart rate variability of obstructive sleep apnea.

Introduction: Obstructive sleep apnea (OSA) is a respiratory sleep disorder. Many of these patients also exhibit autonomic alterations which can be observed through heart rate variability (HRV). Currently, one of the treatments for apnea is continuous positive airway pressure (CPAP).

Forced Swim Reliability for Exercise Testing in Rats by a Tethered Swimming Apparatus.

To assess the physical capacity of rats in forced swim tests, the animal should perform a continuous activity (CON) at the surface to avoid apnea. Bobbing movement (BOB), vigorous paddling known as climbing (CLI), and diving activity (DIV) are inadequate swimming patterns known to increase the exercise intensity variability, impairing the test reliability. Thus, the exercise work accomplished and related physiological variables, such as the blood lactate concentration, may be unreproducible in forced swim.

Coordination analysis of players' distribution in football using cross-correlation and vector coding techniques.

The purpose of this study was to investigate the coordination between teams spread during football matches using cross-correlation and vector coding techniques. Using a video-based tracking system, we obtained the trajectories of 257 players during 10 matches. Team spread was calculated as functions of time.

Artificial gait in complete spinal cord injured subjects: how to assess clinical performance.

Objective: Adapt the 6 minutes walking test (6MWT) to artificial gait in complete spinal cord injured (SCI) patients aided by neuromuscular electrical stimulation.

Method: Nine male individuals with paraplegia (AIS A) participated in this study. Lesion levels varied between T4 and T12 and time post injured from 4 to 13 years.

Analysis of football game-related statistics using multivariate techniques.

Abstract The purpose of this study was to explore football game-related statistics during a competition, using principal component and cluster analyses to determine if it is possible to distinguish the winning teams from the drawing and losing ones. We collected the game-related statistics of the group phase matches of the 2006 World Cup and organised them into a matrix. The principal components of the covariance matrix were calculated.

Identification and agreement of first turn point by mathematical analysis applied to heart rate, carbon dioxide output and electromyography.

Background: The second heart rate (HR) turn point has been extensively studied, however there are few studies determining the first HR turn point. Also, the use of mathematical and statistical models for determining changes in dynamic characteristics of physiological variables during an incremental cardiopulmonary test has been suggested.

Objectives: To determine the first turn point by analysis of HR, surface electromyography (sEMG), and carbon dioxide output (VCO2) using two mathematical models and to compare the results to those of the visual method.

A spectral analysis of team dynamics and tactics in Brazilian football.

The purposes of this study were to characterise the total space covered and the distances between players within teams over ten Brazilian First Division Championship matches. Filmed recordings, combined with a tracking system, were used to obtain the trajectories of the players (n = 277), before and after half-time. The team surface area (the area of the convex hull formed by the positions of the players) and spread (the Frobenius norm of the distance-between-player matrix) were calculated as functions of time.

Quantitative analysis of Brazilian football players' organisation on the pitch.

The purpose of this study was to characterise Brazilian teams' coverage area and spread on the pitch while attacking and defending and to analyse the teams' organisation in tackle and shot on goal situations. We obtained the trajectories of 223 players in eight games with a tracking method. Team area was defined as the area of the convex hull formed by players' positions.

Reproducibility of an incremental treadmill VO(2)max test with gas exchange analysis for runners.

The evaluation of performance through the application of adequate physical tests during a sportive season may be a useful tool to evaluate training adaptations and determine training intensities. For runners, treadmill incremental VO(2)max tests with gas exchange analysis have been widely used to determine maximal and submaximal parameters such as the ventilatory threshold (VT) and respiratory compensation point (RCP) running speed. However, these tests often differ in methodological characteristics (e.

Determination of Force Coresponding to Maximal Lactate Steady State in Tethered Swimming.

The main aim of the present investigation was to verify if the aerobic capacity (AC) measured in tethered swimming corresponds to the maximal lactate steady state (MLSS) and its correlation with 30 min and 400m free style swimming. Twenty-five swimmers were submitted to an incremental tethered swimming test (ITS) with an initial load of 20N and increments of 10N each 3min. After each stage of 3min, the athletes had 30s of interval to blood sample collections that were used to measure blood lactate concentrations ([La]).