OBJECTIVES To study self reported knee joint problems and the energy costs of level walking in soccer players. METHODS Seventeen soccer players and twelve control subjects between 18 and 27 years old participated in the study. A questionnaire was used to establish the amount of participation in soccer and the frequency and extent of knee injuries. The physiological cost index (PCI) was used a...

purpose despite the acknowledged impact of imagery on performance, ecologically sound studies investigating imagery and its effects on performance subcomponents in real games are surprisingly limited. the aim of this study was to investigate the effects of imagery training on passing improvement in elite soccer players. methods sixty nine soccer players taking part in the national championship ...

In this article, we investigated the effectiveness of inhaled salbutamol withtherapeutic dose on the sport-specific performance of non-asthmatic young football players. In a double-blinded, randomised placebo controlled trial with 2-treatment, 2-period crossover design, twenty participants who were non-asthmatic junior professional football players were randomly allocated to two groups. Fifteen...

RoboCup competition as a great test-bed, has turned to a worldwide popular domains in recent years. The main object of such competitions is to deal with complex behavior of systems whichconsist of multiple autonomous agents. The rich experience of human soccer player can be used as a valuable reference for a robot soccer player. However, because of the differences between real and simulated soc...

Objectives: Polymorphisms in α-actinin-3 (ACTN3) gene are considered to be important in the genetic predisposition to human athletic performance. Most of the activities in soccer such as jumping, striking the ball, and running are considered plyometric and explosive. Performance power during such activities depends on the strength of the muscles involved. Therefore, high muscle strength i...

IVe present a. coiiiputatioiial niodel of liuiiian testure segiiieiit+ tioii ancl asgne for its utility in niachine vision. Major tlieories due to dnlesz and Beck attribute preattent,ive texture segmentation to differences in first-order statistics of stininlus features such as oriciitat.ion, size and briglitliess of constituent eleiiients. An dternat,ive ayproa.ch seeks to esploi t psycliopliy...

The purpose of this study was to determine the kinematic variables that identify the quality of velocity in soccer players at different competitive levels and playing positions. This study had two independent variables: 1) a competitive level (competitive and non-competitive players); and 2) a playing position, with four levels (central defenders, wide defenders/midfielders, central midfielders...

The recent point-counter-point exchange arising from the article by Mendez-Villanueva and Buchheit (2013) (Football-specific fitness testing: Adding value or confirming the evidence? Journal of Sports Sciences, 31, 1503-1508) has generated an interesting debate on the real-world utility of fitness testing in professional association football (soccer). In the present authors' opinion, this excha...

Why are performance trade-offs so rarely detected in animals when their underlying physiological basis seems so intuitive? One possibility is that individual variation in health, fitness, nutrition, development or genetics, or 'individual quality', makes some individuals better or worse performers across all motor tasks. If this is the case, then correcting for individual quality should reveal ...