Have we underestimated the kinematic and kinetic benefits of non-ballistic motion?     

David M. Frost  John B. Cronin  Robert U. Newton 《Sports biomechanics / International Society of Biomechanics in Sports》2013,12(3):372-385

Explosive upper-body movements, with which the load is not thrown (non-ballistic), may comprise a phase during which forces are produced in opposition to the motion of the load. Thirty men completed three test sessions (free weight, ballistic, and pneumatic), each consisting of a one-repetition maximum (1-RM) and four explosive repetitions of a bench press at six loads (15, 30, 45, 60, 75, and 90% 1-RM). The end of the lifting phase for the non-ballistic conditions (free weight and pneumatic) was defined by: the point of peak barbell displacement and the point at which the vertical force became negative (positive work). When analysed by peak displacement, the ballistic condition elicited significantly greater mean velocity, force, and power at loads of 15–60% 1-RM compared with the free weight condition. When the period of negative work was removed, the mean free weight velocity, force, and power at loads below 60% 1-RM increased. Consequently, the only differences between the free weight and ballistic conditions were found at loads of 15% and 30% 1-RM. Including a period of negative work may underestimate all kinematic and kinetic variables dependent on the time to, or position of, the end of the lifting phase, for non-ballistic efforts.  相似文献   

From one culture to another: A new study of the F-Test     

Jean Blaise Dupont Ph.D.  Claude Hayoz  Mara Briano 《Journal of Career Development》1992,19(2):99-109

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Subconscious Gatekeeping: The Effect of Death Thoughts on Bias Toward Outgroups in News Writing     

Melissa A. Johnson  John L. Davis  Sean Cronin 《Mass Communication and Society》2013,16(1):4-25

This content analysis examined framing and second-level agenda setting in U.S. newspaper pre-election coverage of the 2006 Mexican presidential elections and the new Mexican expatriate voting law. The authors conducted a quantitative analysis of 161 articles and a qualitative analysis of 36 articles in U.S. newspapers from August 2005 through mid-April 2006. Findings indicated that Andrés Manuel López Obrador received more coverage (59.6%) than Roberto Madrazo (27.8%) or the eventual winner, Felipe Calderón (29.1%). Candidate attributes were highlighted more than Mexican domestic or Mexico–U.S. issues. The dominant procedural frame was the election horse race. The main substantive frames were the election as an extension of U.S.–Mexico economic relations and the election as an extension of Latin American leftist/populist movements. The expatriate voting law was characterized as unsuccessful and blamed on apathetic voters, the Mexican government's faulty implementation, and a corrupt system.  相似文献   

Journal acceptance rates: A cross-disciplinary analysis of variability and relationships with journal measures     

Cassidy R. Sugimoto  Vincent Larivière  Chaoqun Ni  Blaise Cronin 《Journal of Informetrics》2013,7(4):897-906

There are many indicators of journal quality and prestige. Although acceptance rates are discussed anecdotally, there has been little systematic exploration of the relationship between acceptance rates and other journal measures. This study examines the variability of acceptance rates for a set of 5094 journals in five disciplines and the relationship between acceptance rates and JCR measures for 1301 journals. The results show statistically significant differences in acceptance rates by discipline, country affiliation of the editor, and number of reviewers per article. Negative correlations are found between acceptance rates and citation-based indicators. Positive correlations are found with journal age. These relationships are most pronounced in the most selective journals and vary by discipline. Open access journals were found to have statistically significantly higher acceptance rates than non-open access journals. Implications in light of changes in the scholarly communication system are discussed.  相似文献   

Digital Scholarship in the Tenure,Promotion, and Review Process,edited by Deborah Lines Andersen. Armonk,NY: M. E. Sharpe, 2003. x + 277 pp. $64.95 (cloth)/$24.95 (paper). ISBN 0-7656-1114-7     

Blaise Cronin 《The Information Society》2013,29(5):403-404

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The effect of two different 18-week walking programmes on aerobic fitness,selected blood lipids and factor XIIa     

Trent W. Lawton  John B. Cronin  Michael R. McGuigan 《Journal of sports sciences》2013,31(8):701-709

Abstract

The purpose of this project was to evaluate the utility of low- and high-repetition maximum (RM) strength tests used to assess rowers. Twenty elite heavyweight males (age 23.7 ± 4.0 years) performed four tests (5 RM, 30 RM, 60 RM and 120 RM) using leg press and seated arm pulling exercise on a dynamometer. Each test was repeated on two further occasions; 3 and 7 days from the initial trial. Per cent typical error (within-participant variation) and intraclass correlation coefficients (ICCs) were calculated using log-transformed repeated-measures data. High-repetition tests (30 RM, 60 RM and 120 RM), involving seated arm pulling exercise are not recommended to be included in an assessment battery, as they had unsatisfactory measurement precision (per cent typical error > 5% or ICC < 0.9). Conversely, low-repetition tests (5 RM) involving leg press and seated arm pulling exercises could be used to assess elite rowers (per cent typical error ≤ 5% and ICC ≥ 0.9); however, only 5 RM leg pressing met criteria (per cent typical error = 2.7%, ICC = 0.98) for research involving small samples (n = 20). In summary, low-repetition 5 RM strength testing offers greater utility as assessments of rowers, as they can be used to measure upper- and lower-body strength; however, only the leg press exercise is recommended for research involving small squads of elite rowers.  相似文献   

Conference communications     

Anis Chaouachi  Matt Brughelli  Gregory Levin  Nahla Ben Brahim Boudhina  John Cronin  Karim Chamari 《Journal of sports sciences》2013,31(2):151-174

Abstract

The objective of this study was to provide anthropometric, physiological, and performance characteristics of an elite international handball team. Twenty-one elite handball players were tested and categorized according to their playing positions (goalkeepers, backs, pivots, and wings). Testing consisted of anthropometric and physiological measures of height, body mass, percentage body fat and endurance ([Vdot]O_2max), performance measures of speed (5, 10, and 30 m), strength (bench press and squat), unilateral and bilateral horizontal jumping ability, and a 5-jump horizontal test. Significant differences were found between player positions for some anthropometric characteristics (height and percentage body fat) but not for the physiological or performance characteristics. Strong correlations were noted between single leg horizontal jumping distances with 5-, 10-, and 30-m sprint times (r = 0.51–0.80; P < 0.01). The best predictors of sprint times were single leg horizontal jumping with the dominant leg and the distance measured for the 5-jump test, which when combined accounted for 72% of the common variance associated with sprint ability. In conclusion, performance abilities between positions in elite team-handball players appear to be very similar. Single leg horizontal jumping distance could be a specific standardized test for predicting sprinting ability in elite handball players.  相似文献   

Letter from America (Pipe Dreams)     

B Cronin  H Crawford 《International Journal of Information Management》1998,18(6):461-464

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‘Being’ in the coaching world: new insights on youth performance coaching from an interpretative phenomenological approach     

Colum Cronin  Kathleen M. Armour 《Sport, Education and Society》2017,22(8):919-931

Since Heidegger's influential text; Being and time (1927/2005), the phenomenological question of what it means to ‘be’ has generated a vast body of work. This paper reports data from a phenomenological study that investigated what it means to ‘be’ a youth performance coach. An overview of the interpretive phenomenological methods used is followed by presentation of coaches and data. Data analysis resulted in the identification of three constituent ‘essences’ of youth performance coaching: (i) care; (ii) a commitment to educate athletes authentically for corporeal challenges to come; and (iii) working with others to achieve a specialised corporeal excellence. The three identified essences manifest themselves in a broad lifeworld that includes settings on and off the field of play (FOP). Given the very different insights into the practice of coaching that emerge from this study, we argue it would be useful for future studies of coaching practice and coach education to extend their focus to take into account coaches' wider lives both on and off the FOP. We also argue for further exploration of coaching by drawing on phenomenological concepts such as care and relationality.  相似文献   

Digital entrepreneurship: doing business on the information superhighway     

Howard Rosenbaum  Blaise Cronin 《International Journal of Information Management》1993,13(6)

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