e42 2010 Asics Conference of Science and Medicine in Sport / Journal of Science and Medicine in Sport 13S (2010) e1–e107

Self-as-a-model training of left foot Australian Footballpunt kicking in two cases using reversed video footage ofthe player’s right foot kicks

K. Steel 1,∗, R. Adams 2, S. Coulson 2, C. Canning 2

1 University of Western Sydney, Australia2 The University of Sydney, Australia

Introduction: In Australian Football, bilateral punt kickingskill is desirable, but players’ preferred side kick is often bet-ter. To investigate the effectiveness of video self-as-a-modelfor improving performance, two Australian Football playersviewed video-clips of kicks by their non-preferred foot (left)in order to improve the performance ratio of non-preferred topreferred. To display an apparent left foot kick, video-clipsof the athletes performing a right footed kick were reversed.Players were asked to observe the video-clip sequence threetimes a day during the 2-week training period. Methodol-ogy: The video footage was obtained from two AustralianFootball players performing 10 kicks each with the right andleft foot, while aiming at a target placed 50 metres away.Adobe Premier Pro was used to produce a DVD for eachplayer. The DVD displayed footage of their three best rightfoot kicks which was reversed, thus displaying apparent leftkicks. The player watched their DVD three times a day fortwo weeks, after which a post-test was conducted, with aretention test at six weeks. Results: Both players showed asignificant right foot advantage for kick distance after thepre-test, an advantage of 13 metres for player 1 (p < 0.01)and three metres (p = 0.02) for player 2. Thereafter, left footdistance was analysed as a proportion of the distance kickedon the right foot. Bilaterality of performance over the threesessions showed significant improvement. The L/R ratioswere 0.73, 0.79, and 0.83 for player 1 (linear trend oversessions p = 0.01), and were 0.93, 0.96 and 0.99 for player2 (p = 0.04). In terms of accuracy, although the deviationof the kicks from the goal centre lessened over sessions,improvements of 0.8 and 0.2 metres were not significant(p = 0.24 and 0.76, respectively). Player questioning after-wards indicated that both thought they had been observinggood examples of their left foot kicks. Conclusion: The train-ing time needed to influence bilateral skill differences is sogreat that few players or coaches attempt to do so, despiteits advantage. As such, non-preferred side skills are typi-cally worse. This study used a video editing application topresent players with an improved version of their apparentleft side skill performance. Repeated observation of this per-formance was associated with a significant improvement inthe L:R ratio for kick distances in the post-observation periodin both cases. Thus further research into innovative and effi-cient methods of training non-preferred-side skills, such asreversed self-as-a-model footage, are needed.

doi:10.1016/j.jsams.2010.10.550

90

The effect of block, random and combination practiceorders on learning variations of the same task

J. Cheong 1,∗, B. Lay 1, R. Grove 1, R. Razman 2

1 The University of Western Australia, Australia2 University of Malaya, Malaysia

Introduction: Practicing variations of a skill are advan-tageous for optimising motor learning. The purpose of thepresent study was to investigate the effect of three practiceschedules on the acquisition and learning of three variationsof a sport skill. Methods: Fifty-two undergraduate studentswith no prior experience in field hockey practiced threeheight variations of the field hockey flicking skill in eitherblock, random or randomised-blocks practice order. Partic-ipants in the block group completed 15 practice trials ofeach variation repeatedly before moving on to the next andfollowing variation while participants in the random grouppracticed 15 trials of each variation arranged in random order.The randomised-blocks protocol consists of combinations ofblock and random practice orders and participants in thisgroup practiced three blocks of five trials for each varia-tion with these blocks arranged in random order. In total,participants attended six practice sessions and completed atotal of 90 practice trials for each variation by the end of theacquisition phase. The dependent variables were accuracyand speed of the flick skill and participants were instructedto carry out each task as fast and as accurately as possible.All participants completed a pre-test, two acquisition testswhich were held at the third and final practice session and tworetention tests which were held two weeks apart. Data fromthese tests were subjected to a Mixed Model ANOVA for boththe acquisition and retention phases. Results and discussion:During acquisition, overall accuracy increased significantlywith time (F = 15.67, p = 0.00) but overall speed decreasedsignificantly with time (F = 7.03, p = 0.01). During retention,the random group performed significantly better (F = 4.03,p = 0.02) than the block and randomised-blocks conditionsfor accuracy. Speed had significantly increased in the sec-ond retention test (F = 25.77, p = 0.00) to a level unchangedfrom the pre-test but the groups did not differ across time.The results indicate that the amount of time spent in prac-tice was sufficient for improving accuracy and that althoughinitially accuracy was prioritised in favour of speed, in theend, speed performance did not suffer decrements. In addi-tion, the random group practicing in a random practice orderwas more accurate than the block and randomised-blocksgroups practicing under repetitive or combination conditionsrespectively. This finding is in line with practice variabilityand contextual interference research and demonstrates thatpracticing tasks that were similar under random conditions isbeneficial for learning a new motor skill.

doi:10.1016/j.jsams.2010.10.551