Effect of cluster set configurations on power clean technique

Abstract

The purpose of this investigation was to examine the effects of cluster set configurations on power clean technique. Ten male, recreational weightlifters performed three sets of six repetitions at 80% of one repetition max with 0 (P0), 20 (P20) or 40 seconds (P40) inter-repetition rest. During the first and second set of P0, the catch and first pull were in a more forward position during repetition 6 as compared to repetition 1, respectively. During the second set of P40, differences in horizontal displacement were found between repetitions 1 and 6 for the second pull and the loop. During the third set of P40, differences in horizontal displacement were found between repetitions 1 and 6 for the first pull, transition, and beginning of the second pull. No differences in horizontal displacement were found between repetitions 1 and 6 during P20. During each set of P0, vertical displacement decreased between repetitions 1 and 6 (1.02 ± 0.07 m vs. 0.94 ± 0.06 m; Mean ± s). Cluster set configurations led to the maintenance of vertical displacement throughout all sets. The results demonstrate cluster set configurations with greater than 20 seconds inter-repetition rest maintain weightlifting technique to a greater extent than a traditional set configuration.     

Interactions among Dietary Pattern,Physical Activity and Skinfold Thickness

Abstract

This study was designed to assess the effects of a specifically designed perceptual-motor training program on the level of perceptual-motor development, self-concept, and academic ability of kindergarten children. Subjects for the study were 40 kindergarten children randomly assigned to 1 of 2 groups. Each group received the same kindergarten program with one exception, the experimental group was exposed to a specifically designed perceptual-motor program 30 min daily for 5 mo, while the control group received a free play period for 30 min daily. Results of the study indicated that the data tended to support the specificity of training concept. The variables showing the greatest change were the perceptual-motor tests which measured changes on specific aspects of the training program. There appeared to be some immediate transfer to academic abilities but this was not pronounced enough to suggest that perceptual-motor training was of real benefit in developing academic abilities for normal kindergarten children. In addition the follow-up test indicated no long term effects on academic performance.     

Effect of Caffeine Ingestion on Cardiorespiratory Endurance in Men and Women

Abstract

The effect of caffeine ingestion on submaximal endurance performance of 15 females and 13 males was investigated. After completing a [Vdot]O ₂ max test, each subject performed two submaximal cycling tests at approximately 75% of [Vdot]O ₂ max to exhaustion. For the caffeine (C) trials, 300 mg of caffeine was added to 250 ml of decaffeinated coffee and ingested one hour prior to the exercise. The decaffeinated (D) trial involved consuming 250 ml of decaffeinated coffee an hour prior to the test. The C and D trials were administered randomly using a standard double blind design. Physiological parameters were monitored each 9, 10, and 11 minute intervals throughout each trial and averaged. As expected the [Vdot]O ₂ (L · min ^?1 ), [Vdot]E and work outputs (kgm) were significantly (p < 0.001) higher for the males than the females. All other variables, time to exhaustion, [Vdot]O ₂ (ml · kg · min ^?1 ), R, HR, and rating of perceived exertion (RPE) were not significantly (p > 0.05) different between the sexes for either the C or D trials. Time to exhaustion was 14.4 and 3.1% longer for the C trials for the females and males, respectively, however these increases were not significant (p > 0.05). Furthermore, there were no significant differences (p > 0.05) for any of the measured variables during successive 10 minute work intervals between the C and D trials for either sex. These results do not support the general use of caffeine in moderate amounts as an ergogenic aid for either males or females, but from a practical point it appears that caffeine may have an ergogenic effect on specific individuals.     

Cognitive Style and Learner Strategy Interaction in the Performance of Primary and Related Maze Tasks

Abstract

The effect of designated learning strategies and reflective versus impulsive cognitive styles on performance in a maze learning task was investigated. Twenty-four female subjects were randomly assigned to a strategy or control group. The strategies group was provided with three potentially effective strategies (imagery, rhythm, and feedback) as identified by an information processing task analysis procedure. The Matching Familiar Figures test further classified subjects within the two groups according to their preferred styles of responding. Eleven primary task trials were administered with direct view of maze and four related task trials were completed with an indirect view of it. Traversal speed and time in the incorrect pathways were analyzed with a 2 × 2 × 7 (Strategies × Cognitive Styles × Trial Blocks) repeated measures ANOVA. A significant three-way interaction was found for both dependent measures. As hypothesized, during the primary task the control reflective subjects traversed the maze more slowly than the control impulsive subjects. However, the strategies reflective subjects completed the maze with the same speed as strategies impulsives. The incorrect pathways × time interaction revealed that the control reflective subjects spent less time in the incorrect pathways during the related task than the control impulsives. No significant differences were found for strategies reflectives or impulsives. These findings indicate that, for this maze task that emphasized speed, the performance of reflective and impulsive subjects was facilitated by appropriate learning strategies.     

New Frontiers in Visual Search: An Exploratory Study in Live Tennis Situations

This study compares the motor skills and physical fitness of school-age children (6-12 years) with visual impairments (VI; n = 60) and sighted children (n = 60). The relationships between the performance parameters and the children's body composition are investigated as well as the role of the severity of the impairment. The degree of VI did not differentially affect the outcomes. Compared to their sighted peers, the children with VI scored lower on the locomotor and object control skills as assessed with the Test of Gross Motor Development-2, and the physical fitness (Eurofit) parameters of plate tapping, the standing broad jump, the modified 5 × 10-m shuttle run, and 20-m multistage shuttle run (20-MST). Their body mass and body fat indexes were inversely correlated with the standing broad jump and the 20-MST, but positively correlated with handgrip strength. Moreover, significant inverse correlations were found between their locomotor and object control skills on the one hand and plate tapping and the 5 × 10-m shuttle run on the other hand. Given the relatively high proportion (25%) of overweight/obese children within the VI sample, educators are recommended to promote health-related activities and help enhance motor skills in this population.     

Examining the influence of modularity and knowledge management (KM) on dynamic capabilities: Insights from a call center

Modularity in organizations can facilitate the creation and development of dynamic capabilities. Paradoxically, however, modular management can also stifle the strategic potential of such capabilities by conflicting with the horizontal integration of units. We address these issues through an examination of how modular management of information technology (IT), project teams and front-line personnel in concert with knowledge management (KM) interventions influence the creation and development of dynamic capabilities at a large Asia-based call center. Our findings suggest that a full capitalization of the efficiencies created by modularity may be closely linked to the strategic sense making abilities of senior managers to assess the long-term business value of the dominant designs available in the market. Drawing on our analysis we build a modular management-KM-dynamic capabilities model, which highlights the evolution of three different levels of dynamic capabilities and also suggests an inherent complementarity between modular and integrated approaches.     

Disciplining the Future: A Critical Organizational Analysis of Internet Studies

This article provides a critical, cautionary stance toward the future structure of “Internet studies” as a field. A social constructionist reading of the process of organizing reveals the ways in which apparently obdurate structures are constructed and negotiated through everyday discursive practices. Subsequent structures and practices function ideologically to control organizational members in a concertive fashion by shaping and directing the conceptual frameworks for inquiry and action in a seemingly natural way. Definitions and metaphors construct conceptual boundaries of meaning for the field of inquiry, delimiting and protecting over time what counts as Internet and Internet studies. Over time, origins of knowledge are hidden within the structure of the organizations and a culture of unobtrusive control emerges. Unless radical measures are taken to reflexively interrogate everyday routines and habitual ways of talking in academic environments, the future field of Internet studies will not transcend the traditions of the academy but will be entrenched in and reproduce traditional structures and a traditional scholarly enterprise.     

Effects of Two Instructional Approaches on Skill Development,Knowledge, and Game Performance

Two instructional approaches that have been of interest in promoting sport have been the Sport Education Model (SEM) and the Traditional Style (TS) of teaching physical education. The purpose of this study was to investigate how SEM and TS would affect skill development, knowledge, and game performance for volleyball at the secondary level. A 2 × 3 (group × time) research design was utilized on 47 secondary students testing volleyball skills, knowledge, and game performance. Participants were placed in either the SEM or the TS via stratified randomization, and then were tested pre, mid, and post intervention through the 20-lesson volleyball unit. The 2 × 3 repeated measures Analysis of Variances (ANOVAs) with Bonferroni correction revealed no significant difference between models for skills and knowledge, but there was for game performance for group [F(1, 45) = 10.27, p < .008, η² = .19], time [F(2, 90) = 8.62, p < .008, η² = .16], and group × time interaction [F(2, 90) = 8.43, p < .008, η² = .16]. If the goal of the physical education program is to promote quality game play, the SEM may be more effective than the TS.     

Youths with migration backgrounds and their experiences of physical education: an examination of three cases

While understanding young people has never been easy, migration trends make it increasingly difficult. Many classrooms have become culturally heterogeneous and teachers are often faced with pupils with diverse linguistic and cultural heritages. Current scholarship suggests that as a discipline, physical education has not adapted to this diversity. In fact, commentators have suggested that physical education alienates pupils from minority groups and that traditional practices work to maintain cultural difference. The broad objective of this paper is to provide insights into how physical education intersects with biographies shaped by migration. Drawing from a case study investigation, this paper presents interview data from three youths with migration backgrounds living in a German-speaking region of Switzerland. The cases were selected because they highlight various ways in which physical education (PE) comes to make sense for adolescents. The key arguments that we develop are that ethnicity often works at an implicit level in PE, that young people experience the effects of migration backgrounds in diverse ways, and that migrants themselves support official educational discourses that work to disadvantage people with migration backgrounds. A key implication is that in a cultural milieu in which generalisations are normal and sometimes considered desirable, both researchers and practitioners need to be wary of racialising discourses. As an alternative, it is suggested that focusing on individual processes can improve the conceptualisation and implementation of physical education pedagogies.