Effect of verbal instructions and image size on visual search strategies in basketball free throw shooting

We assessed the effects on basketball free throw performance of two types of verbal directions with an external attentional focus. Novices (n = 16) were pre-tested on free throw performance and assigned to two groups of similar ability (n = 8 in each). Both groups received verbal instructions with an external focus on either movement dynamics (movement form) or movement effects (e.g. ball trajectory relative to basket). The participants also observed a skilled model performing the task on either a small or large screen monitor, to ascertain the effects of visual presentation mode on task performance. After observation of six videotaped trials, all participants were given a post-test. Visual search patterns were monitored during observation and cross-referenced with performance on the pre- and post-test. Group effects were noted for verbal instructions and image size on visual search strategies and free throw performance. The 'movement effects' group saw a significant improvement in outcome scores between the pre-test and post-test. These results supported evidence that this group spent more viewing time on information outside the body than the 'movement dynamics' group. Image size affected both groups equally with more fixations of shorter duration when viewing the small screen. The results support the benefits of instructions when observing a model with an external focus on movement effects, not dynamics.     

Individual pathways in the development of forceful throwing

Halverson, Roberton, and Langendorfer (1982) reported the development of children ages 6-13 years filmed longitudinally performing the forceful overarm throw. These authors described the children's progress through developmental sequences for trunk, humerus, and forearm actions; however, they did not study developmental relationships ("profiles") across these components. This paper reports how the profiles changed in the same children across trials within filming sessions and over time. The data revealed both common and individual developmental pathways. The frequencies of some pathways were not chance occurrences (p < or = .01), suggesting that within-person constraints eliminated certain movement relationships while encouraging others. The authors hypothesize that the kinematics of trunk rotation may serve as a control parameter for pattern change.     

Cognitive interference during competition among volleyball players with different goal orientation profiles

In this study, we examined interfering thoughts during sport competition among university volleyball players as a function of dominant goal orientation and outcome. In particular, we investigated the performance worries and thoughts of escape experienced while performing in athletes with high task and low ego orientation and athletes with high ego and low task orientation. Goal orientations were assessed before the start of a volleyball tournament, whereas cognitive interference was assessed on three different occasions after games. The results revealed no consistent differences for performance worries. In contrast, in all analyses we found that athletes with high ego and low task orientations reported more thoughts of escape when losing than when winning, and more thoughts of escape than athletes with high task and low ego orientations when winning or losing. The results support in part the suggestion that a high ego orientation, when not accompanied by a high task orientation, can be linked to motivationally maladaptive cognitions.     

Book reviews

Gaining Independence: A Manual for Planning the Launch of a Nonprofit Electronic Publishing Venture, version 1.0 by Howard Goldstein Published by SPARC, available online: http://www.arl.org/sparc/GI Indexers and Indexing in Fact and Fiction edited by Hazel K. Bell The British Library, London, 2001. Pp. 160. Paper, £16. ISBN 0-7123-4729-1 Preservation Management of Digital Materials: A Handbook by Maggie Jones and Neil Beagrie The British Library, Nov. 2001. Pp. 145. Spiral bound, £15.00. ISBN 0 7123 0886 5. Copies can be ordered from Turpin Distribution Services Ltd. Publishing Law, 2nd edn by Hugh Jones and Christopher Benson Routledge, 2002. Cased, £65.00, ISBN 0-415-26153-8; paper, £24.99, ISBN 0-415-26154-6 How to Survive Peer Review by Elizabeth Wager, Fiona Godlee and Tom Jefferson London: BMJ Books, 2002. Pp. v + 62. £12.95. ISBN 0-7279-1686-6     

The effect of ball carrying method on sprint speed in rugby union football players

Different methods of ball carrying can be used when a player runs with the ball in rugby union. We examined how three methods of ball carrying influenced sprinting speed: using both hands, under the left arm and under the right arm. These methods were compared with running without the ball. Our aim was to determine which method of ball carrying optimizes sprinting speed. Altogether, 48 rugby union players (age 21 +/- 2 years, height 1.83 +/- 0.1 m, body mass 85.3 +/- 12 kg, body fat 14 +/- 5%; mean +/- s) were recruited. The players performed twelve 30-m sprints in total (each player performed three trials under each of three methods of carrying the ball and sprinting without the ball). The design of the study was a form of Latin rectangle, balanced across the trial order for each of the methods and for pairwise combinations of the methods in blocks of four per trial. Each sprint consisted of a 10-m rolling start, followed by a 20-m timed section using electronic timing gates. Compared with sprinting 20 m without the ball (2.58 +/- 0.16 s), using both hands (2.62 +/- 0.16 s) led to a significantly slower time (P < 0.05). Sprinting 20 m with the ball under the left arm (2.61 +/- 0.15 s) or under the right arm (2.60 +/- 0.17 s) was significantly quicker than when using 'both hands' (P < 0.05), and both these methods were significantly slower than when running without the ball (P < 0.05). Accordingly, running with the ball in both hands led to the greatest decrement in sprinting performance, although carrying the ball under one arm also reduced the players' sprinting ability. Our results indicate that to gain a speed advantage players should carry the ball under one arm.     

Motivation for physical activity in young people: entity and incremental beliefs about athletic ability

Three studies are reported of children and youth aged 11-19 years (n = 3478) examining the nature of beliefs about athletic ability. Drawing on related research in academic, moral and stereotyping domains, development of a psychometric instrument assessing athletic ability beliefs is detailed. Support was found for a multidimensional hierarchical structure that is invariant across age and gender. Confirmatory factor analysis revealed a structure comprising two higher-order factors of entity and incremental beliefs underpinned by beliefs that athletic ability is stable and a gift (entity), and is open to improvement and can be developed through learning (incremental). Incremental beliefs, indirectly through a task goal orientation, and entity beliefs directly, predicted self-reported amotivation towards physical education and sport. On the other hand, enjoyment of physical activity in youth was predicted directly by task orientation and incremental beliefs. Predictions concerning the moderating role of perceived competence were not supported. Our findings highlight the importance of ability beliefs and goals in understanding the determinants of physical activity in children and youth.     

Monitoring meaningful rugby ratings

The performance of individual rugby players can be quantified using multivariate analysis and modified control chart methodology. Using factor analysis, multivariate data are reduced to five orthogonal factors (key performance indicators). These factors are reduced to a single measure of performance by modifying control chart ideology. By comparing the observed peformances with 'unattainable perfection' rather than the average, a statistic that is suitable for monitoring the performance of individual rugby players with control charts is obtained for use by coaches and selectors.