The effect of time of introduction and amount of mental practice on the performance of the back roll extension

The purpose of the study was to investigate the effect of the time of introduction and the amount of mental practice on the performance of the back roll extension. Performance was measured by the average from three judges' ratings of form and success in passing through the handstand position.

Thirty-two female college students enrolled in two elementary tumbling classes at The University of Tennessee, Knoxville, served as subjects for this study. The subjects were measured for body weight and shoulder strength and then were randomly assigned to one of four treatment groups. The treatment groups were: (a) early introduction and two minute periods of mental practice, (b) late introduction and two minute periods of mental practice, (c) early introduction and three minute periods of mental practice, and (d) late introduction and three minute periods of mental practice.

All physical practice trials of the back roll extension were videotaped. The judges evaluated the first three performances (pretest) and the three test performances (posttest) from the videotape recordings. The judges used a five-point scale to evaluate the form of the subjects' performance of the back roll extension. A Pearson correlation coefficient (r) was used to test the objectivity of the judges' ratings. A two-way ANOVA was used to analyze the rating scores. The judges used a dichotomous scale (yes or no) to evaluate the success of each subject to pass through the handstand position on performances of the back roll extension. Crosstabulations were used to evaluate the scores on frequency of success and failure.

The analysis of variance indicated that there was no significant (a) effect of time of introduction of mental practice, (b) effect of amount of mental practice, or (c) interaction effect on the form of the back roll extension. Crosstabulations indicated more subjects who mentally practiced late were successful than subjects who mentally practiced early.