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Waneen W. Spirduso, Britta G. Schoenfelder-Zohdi, Jonghwan Choi and Susan M. Jay

This study investigated age-related differences in tapping speed with respect to warm-up and fatigue effects and also with respect to task complexity. An additional purpose was to determine the site of age-related slowing in stationary tapping. Adult females from three different age groups were asked to tap as fast as possible for 25 s with a specified digit combination by depressing microswitches on one or two metal boxes that were mounted on a data acquisition board. All groups showed a warm-up period during the first block, reached their peak tapping speed during the second block, and then gradually fatigued, as indicated by a decreasing number of taps. These findings suggest that to assess true tapping speed, a trial should not last more than 15 s, or the results may be confounded by fatigue effects. It was found that tapping with the thumb and index finger simultaneously is more difficult than tapping with one or both index fingers, regardless of age.

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R. Glenn Cummins, Norman E. Youngblood and Mike Milford

Sport telecasts are frequently the showcase and testing ground for innovative broadcast technologies. One particularly novel example is ESPN’s coverage of college athletics via its multiscreen, or mosaic, format. This experiment tested the impact of its visual complexity by comparing the response of fans high and low in team identification to this format versus a traditional presentation of dull and exciting game play. For highly identified spectators, this format was a detriment to their appreciation of game play, whereas the format had little impact for viewers with low levels of team identification. Moreover, independent of degree of team identification, viewers reported a more negative evaluation of this technique than of a traditional broadcast, and results were consistent regardless of the dull or exciting nature of game play.

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Tiago M. Barbosa, Wan Xiu Goh, Jorge E. Morais and Mário J. Costa

The aim was to examine the variation of linear and nonlinear proprieties of the behavior in participants with different levels of swimming expertise among the four swim strokes. Seventy-five swimmers were split into three groups (highly qualified experts, experts and nonexperts) and performed a maximal 25m trial for each of the four competitive swim strokes. A speed-meter cable was attached to the swimmer’s hip to measure hip speed; from which speed fluctuation (dv), approximate entropy (ApEn) and fractal dimension (D) variables were derived. Although simple main effects of expertise and swim stroke were obtained for dv and D, no significant interaction of expertise and stroke were found except in ApEn. The ApEn and D were prone to decrease with increasing expertise. As a conclusion, swimming does exhibit nonlinear properties but its magnitude differs according to the swim stroke and level of expertise of the performer.

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Ruud J. R. Den Hartigh, Paul L. C. Van Geert, Nico W. Van Yperen, Ralf F. A. Cox and Christophe Gernigon

This study on psychological momentum (PM) in sports provides the first experimental test of an interconnection between short-term PM (during a match) and long-term PM (across a series of matches). Twenty-two competitive athletes were striving to win a prize during a rowing-ergometer tournament, consisting of manipulated races. As hypothesized, athletes who had developed long-term positive PM after two successful races were less sensitive to a negative momentum scenario in the third race, compared with athletes who had developed long-term negative PM after two unsuccessful races. More specifically, the exerted efforts, perceptions of momentum, and self-efficacy were higher for participants who had developed long-term positive PM, and their perceptions of momentum and self-efficacy decreased less rapidly. These results illustrate a typical complex dynamical systems property, namely interconnected time scales, and provide deeper insights into the dynamical nature of PM.

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David R. Mutimer and Brian T.P. Mutimer

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Aftab E. Patla and Anne Shumway-Cook

Mobility, the ability to move independently, is critical to maintaining independence and quality of life. Among older adults, mobility disability results when an individual cannot meet the demands of the environment. Current approaches to defining mobility rely on distance and time measures, or decompose mobility into subtasks (e.g., climbing, sit to stand), but provide limited understanding of mobility in the elderly. In this paper, a new conceptual framework identifies the critical environmental factors, or dimensions, that operationally define mobility within a given community, such as ambient conditions (light levels, weather conditions) and terrain characteristics (stairs, curbs). Our premise is that the environment and the individual conjointly determine mobility disability. Mobility in the elderly is defined not by the number of tasks a person can or cannot perform, but by the range of environmental contexts in which tasks can be safely carried out: the more disabled, the more restrictive the dimensions.

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Michael B. Martin and Mark H. Anshel

Two experiments were conducted to examine the effect of self-monitoring (SM) strategies on motor performance of varied difficulty. In a pilot test, participants’ perceptions of task difficulty agreed with performance on the easy task. Participants perceived the hard task to be significantly more difficult than indicated by the performance scores and perceived the easy task to be significantly less difficult than their performance on the complex task (p < .05). In the subsequent experiment, subjects performed 90 trials on either the difficult or easy motor task using either positive self-monitoring (PSM), negative self-monitoring (NSM), or no self-monitoring. MANOVAs indicated that PSM resulted in superior performance in comparison to NSM across trials while performing the difficult task (p < .05). In the easy task, PSM was inferior to NSM on motor performance across trials (p < .01). Further results also indicated that negative affect significantly decreased for PSM performing the difficult task, and for NSM performing the easy task.

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Steve Swanson and Aubrey Kent

The way in which leaders in sport organizations are evaluated by their employees is dependent upon perceived levels of credibility and implicit theories of leadership. Leader knowledge and expertise play significant roles in this process, yet both have been treated as comprehensive constructs irrespective of specific knowledge domains. Drawing from the education literature, this research looks to disentangle the global perspective used by the credibility and prototypicality literatures. It is proposed that employees in sport organizations expect managers to possess domain-specific expertise which is separate from the functional area requirement. Two different samples including professional sport employees and sport management students were used, with confirmatory factor and conjoint analyses used to test the research hypotheses. The results support the notion that distinct psychological processes exist within sport organizations, and that sport domain knowledge and expertise are distinct constructs which play important roles in the perception of leaders within this context.

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Ludovic Seifert, Dominic Orth, Jérémie Boulanger, Vladislavs Dovgalecs, Romain Hérault and Keith Davids

This study investigated a new performance indicator to assess climbing fluency (smoothness of the hip trajectory and orientation of a climber using normalized jerk coefficients) to explore effects of practice and hold design on performance. Eight experienced climbers completed four repetitions of two, 10-m high routes with similar difficulty levels, but varying in hold graspability (holds with one edge vs holds with two edges). An inertial measurement unit was attached to the hips of each climber to collect 3D acceleration and 3D orientation data to compute jerk coefficients. Results showed high correlations (r = .99, P < .05) between the normalized jerk coefficient of hip trajectory and orientation. Results showed higher normalized jerk coefficients for the route with two graspable edges, perhaps due to more complex route finding and action regulation behaviors. This effect decreased with practice. Jerk coefficient of hip trajectory and orientation could be a useful indicator of climbing fluency for coaches as its computation takes into account both spatial and temporal parameters (ie, changes in both climbing trajectory and time to travel this trajectory).

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Lindsay Warren, Russell Baker, Alan Nasypany and Jeffrey Seegmiller

The core is central to almost all extremity movements, especially in athletics. Running, jumping, kicking, and throwing are dependent on core function to create a stable base for movement. Poor core strength, endurance, stiffness, control, coordination, or a combination thereof can lead to decreased performance and increased risk of injury. Due to the core’s many complex elements, none of which are more or less important than the next, it is imperative that athletic trainers have a systematic and comprehensive plan for assessing and treating patients with stability or motor control dysfunctions of the entire spinal stabilizing system. The purpose of this clinical commentary is to outline the structural (anatomical) components of the core and their functions, establish the elements of core stability (functional), review these elements’ importance in decreasing the risk of injury, and discuss the application of this information in athletic training.