Integra

Introduction

Effects of different practicing schedules have been studied in different motor skills (Dunham 1976, 1978, Kunos 1983, Elliot 1985, Tosi 1989, Hart 2000). The purposes of this study are a). To explore the effects of the performance in the different practicing schedules. b). To identify the practicing schedule which leads to the most improvement occurred in the learning of the overarm throw.

Methods

Forty-six subjects were divided into three groups: group with right and left hand practice (Alternative schedule), group with right hand practice (Right hand schedule) and group with left hand practice (Left hand schedule). A three-factor (group, hand and test) with-subject repeated measures randomized-groups design was used in this study. 14 fifty-five minute practicing sessions were conducted during the two months. Each subject of three experimental groups made 560 practices of the overarm throw in practice session and carried out 72 testing trials for Pre-test, Mid-test and Post-test totally. Motion Analysis System (Santa Rosa, CA) and A Kistler multicomponent force platform system (Model 9728) were employed to collect kinesiological measures including performance error variables, kinematic variables and kinetic variables. All the data treatment was conducted with SPSS.

Results

The results of performance errors displayed that distinct improvements of RE were demonstrated in Alternative schedule group (14.91%) and Right hand schedule group (17.24%) from Pretest to Posttest whereas less improvements were appeared in Left hand schedule group (6.19%) in relation to the performance of the right overarm throw. It is implied that alternative schedule and right hand schedule in contrast to left hand schedule have achieved the largest practice effect. Similarly, the results in the left overarm throw showed that explicit progress of RE was made from Pretest to Posttest in Alternative schedule group (25.38%) and Left hand schedule group (34.27%) while less improvements existed in Right hand schedule group (3.07%). Alternative schedule and left hand schedule in contrast to right hand schedule displayed the more improvements in the performance errors among three groups. On the other hand, the results of kinematic analysis in the right overarm throw illustrated apparent improvements of velocity and acceleration in Right hand schedule group (6.20% and 4.09%) and Alternative schedule group (7.28% and 21.91%). Meanwhile, the improvements of ball velocity and acceleration in the left overarm throw from Pretest to Posttest were as follows: Right hand schedule group (3.19% and 15.40%), Left hand schedule group (5.23% and 16.43%) and Alternative group (12.12% and 12.58%).

Discussion

Alternative schedule is the most efficient practicing schedule in regard to improving the overall performance of the overarm throw even though other two practicing schedules are productive as well. While right hand schedule is mainly to better the performance of the right overarm throw, and left hand schedule concentrates the practice effects on the performance of the left overarm throw. Alternative schedules had developed the performance of both right and left overarm throws as much as right hand schedule and left hand schedule did on both right and left overarm throws respectively. That is, the alternative schedule could simultaneously enhance the performance of both right and left hands within the same amount of practice as the right hand schedule and the left hand schedule could. The efficiency of alternative schedule was doubled. It is suggested that alternative schedule should be employed in the learning of bilateral motor tasks in order to optimize the process of learning.

Reference

[1]. Dunham, P. J. (1978) Effect of practice order on the efficiency of bilateral skill acquisition. Research Quarterly, 48, P284-287.
[2]. Elliott, D. (1985) Manual asymmetries in the performance of sequential movement by adolescents and adults with Down’s syndrome. American Journal of Mental Deficiency, 90, P90-97.
[3]. Kunos, A. (1983) A transzfer hatasa a hajitas tavolsagara 6 eves korban. (Effect of transfer on the throwing performance in age of 6 years.) Testnevelisi Foiskola Koezlemenyei (Budapest), 2, P63-81.
[4]. Tosi, S. H. C. F. (1989) Transferencia bilateral de uma habilidade motora complexa do basquetebol. Universidade de Sao Paulo, Sao Paulo, Thesis (M. Ed.), P147.