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Ian Varley, Ryan Lewin, Robert Needham, Robin T. Thorpe and Ross Burbeary

Trent University ethics committee. Measures Sprint distance, total distance, the number of accelerations and decelerations and the number of sprints ( Di Salvo et al., 2006 ) were assessed using Prozone Matchviewer (Prozone® Sports Ltd, Leeds, United Kingdom). Prozone Matchviewer had been previously shown to be a valid and reliable ( Bradley et al., 2007 ; Di Salvo et al., 2006 ) measure of performance characteristics. A sprint was considered when a player reached a speed in access of 7 m·s -1 , accelerations and decelerations were categorised as a change in

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Konstantinos Papanikolaou, Athanasios Chatzinikolaou, Theodoros Pontidis, Alexandra Avloniti, Chariklia K. Deli, Diamanda Leontsini, Dimitrios Draganidis, Panagiotis D. Tsimeas, Lefteris Rafailakis, Athanasios Z. Jamurtas, Peter Krustrup, Magni Mohr and Ioannis G. Fatouros

Introduction Team sports such as soccer, basketball and volleyball are characterized by frequent changes in activity patterns, mostly consisting of repetitive high-intensity actions (e.g. sprints, decelerations, accelerations, jumping, sliding, shooting and shuffling) interrupted by periods of low-to-moderate intensity or even standing still ( McInnes et al., 1995 ; Mikołajec, 2012, 2017; Mroczek et al., 2014 ; Puente et al., 2017 ). Cardiovascular loading and muscle and blood responses during basketball and soccer games, indicate mobilization of all energy

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Dorin Sarafoleanu and Raluca Enache

Abstract

Whiplash syndrome is a quite common pathology and can be defined as a neck injury produced by a sudden acceleration-deceleration, the consequence of which is a sudden forward and backward movement of the head and neck. The main production mechanism is a sudden acceleration-deceleration process that has as a consequence the sudden extension/flexion of the neck. Starting from the many structures involved, the whiplash syndrome is an interdisciplinary challenge (ENT specialist, neurologist, orthopedist, ophthalmologist, psychologist) and can be described by multiple signs and symptoms.

Whiplash syndrome is a complex pathology both through the mechanism of production and symptoms, and through the forensic implications that it has. The interdisciplinary medical collaboration, the implementation of stricter rules on wearing the seat belt and the development by car manufacturers of chairs and head restraints that protect the head and neck of passengers, would be the preventive step in the occurrence and especially the chronicization of these lesions.

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Aleš Filipčič, Bojan Leskošek, Goran Munivrana, Gabriela Ochiana and Tjaša Filipčič

speed during a tennis match, and more specifically, to measure the tennis player’s speed before, during and after the split-step. We were most interested in determining whether there were any differences in deceleration before and acceleration after the split-step in various types of strokes as well as whether there were any differences in tennis players’ movement regarding their sex, age and sports level. The purposes of the present study were: 1) to examine speed before, during and after the split-step, deceleration before and acceleration after the split-step in

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A. Vanessa Bataller-Cervero, Héctor Gutierrez, Jacobo DeRentería, Eduardo Piedrafita, Noel Marcén, Carlos Valero-Campo, Manuel Lapuente and César Berzosa

measuring, and a radar gun was not considered as a gold standard in instantaneous speed control. If GPS devices can be validated, they would be very useful in future studies in both team and individual sports, where speed assessment is needed. One of the least studied variables is the ability of GPS devices to determine distance and speed during accelerations and decelerations. This speed is even more important and influential for team sports games than average time measured at different speeds, which has been widely determined ( Bacon and Mauger, 2017 ; Castillo et al

Open access

Matthias Wilhelm Hoppe, Christian Baumgart, Mirko Slomka, Ted Polglaze and Jürgen Freiwald

Introduction During the past few decades, the extensive application of time-motion analyses has substantially increased the knowledge of match running demands for elite soccer players ( Hoppe et al., 2015b ). In most studies, video or global position system (GPS) derived time-motion data were collected to determine the time spent, distance covered or frequency in various velocity categories ( Carling et al., 2008 ). However, for soccer, this velocity based approach is potentially not appropriate due to the frequent accelerations and decelerations performed

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David Casamichana, Paul S Bradley and Julen Castellano

and Drust, 2009). The inconsistency reported for various SSG pitch dimensions means that a greater understanding is needed of how these metrics impact players physiological responses and time-motion characteristics (Stone and Kilding, 2009). Variations in the number of players per team ( Rampinini et al., 2007 ) or the presence of goalkeepers ( Castellano et al., 2013d ) could be behind these inconsistencies. Typically, small pitch dimensions result in more accelerations-decelerations ( Castellano et al., 2015 ; Hodgson et al., 2016) and less distance covered at

Open access

Javier Sanchez-Sanchez, Mario Sanchez, Daniel Hernández, Oliver Gonzalo-Skok, David Casamichana, Rodrigo Ramirez-Campillo and Fabio Y. Nakamura

completed (DT) and total distance relative to match duration (D rel ); the percentage of DT in acceleration =1.5 m/s 2 [%DAC = (DT / DAC) x 100]; the percentage of DT in deceleration =-1.5 m/s 2 [%DEA = (DT / DEA) x 100]; and the percentage of DT performed at different speeds: 0-0.4 km/h [%V1 = (DT / DV1) x 100] (standing); 0.5-3.0 km/h [%V2 = (DT / DV2) x 100] (walking); 3.1-8.0 km/h [%V3 = (DT / DV3) x 100] (jogging); 8.1-13.0 km/h [%V4 = (DT / DV4) x 100] (medium-intensity running); 13.1-18.0 km/h [%V5 = (DT / DV5) x 100] (high-intensity running); ≥18.1 km/h [%V6

Open access

Sergio Maroto-Izquierdo, David García-López and José A de Paz

Introduction Muscle strength and power are critical in competitive team sports as these abilities are the basis of specific actions that determine performance (i.e. throwing, jumping, running and hitting). In these sport modalities, that include handball, players are required to repeatedly carry out short, explosive efforts such as accelerations and decelerations during sprints with changes of direction. Handball involves high-intensity short duration exercise, requiring a well-developed aerobic fitness, speed and strength ( Massuca et al., 2014

Open access

K. Arun Venkatesh and N. Mathivanan

Abstract

Design of an acceleration measurement system using a MEMS accelerometer to measure acceleration of automobiles in all the three axes is presented. Electronic stability control and anti-lock breaking systems in automobiles use the acceleration measurements to offer safety in driving. The system uses an ARM microcontroller to quantize the outputs of accelerometer and save the measurement data on a microSD card. A LabVIEW program has been developed to analyze the longitudinal acceleration measurement data and test the measurement system. Random noises generated and added with measurement data during measurement are filtered by a Kalman filter implemented in LabVIEW. Longitudinal velocity of the vehicle is computed from the measurement data and displayed on a graphical chart. Typical measurement of velocity of a vehicle at different accelerations and decelerations is presented.