Jerry R. Thomas
Karen E. French and Jerry R. Thomas
This study examined the relationship of sport-specific knowledge to the development of children's skills in basketball. Two experiments were conducted. The first compared child expert and novice basketball players in two age leagues, 8-10 years and 11-12 years, on the individual components of basketball performance (control of the basketball, cognitive decisions, and motor execution) and on measures of basketball knowledge, dribbling skill, and shooting skill. Child expert players of both age groups possessed more shooting skill and more basketball knowledge. A canonical correlation analysis indicated that basketball knowledge was related to decision-making skill, whereas dribbling and shooting skill were related to the motor components of control and execution. Experiment 2 examined the changes in the individual components of performance, basketball knowledge, dribbling skill, and shooting skill from the beginning to the end of the season. Subjects improved in the cognitive decision-making and control components of performance across the course of the season, and basketball knowledge increased from the beginning to the end of the season. Only basketball knowledge was a significant predictor of the decision-making component at the end of the season. The overall results of Experiments 1 and 2 indicate that the development of the sport knowledge base plays a salient role in skilled sport performance of children.
Tarra Rawdon, Rick L. Sharp, Mack Shelley and Jerry R. Thomas
This paper is a meta-analysis of the role of nutritional supplements in strength training focusing on the effects of placebo treatments. We address specifically the results from meta-analysis of 334 fi.ndings from 37 studies of the effect of nutritional supplements and physical fitness interventions on strength, stamina, and endurance outcomes, controlling for main effects of the group on which the results were obtained (placebo, treatment, control, for pretest or posttest), with covariates for age, gender, randomization, double-blind procedures, study duration, training load, training frequency, and training status. Finding show that there are significant placebo effects accounting for a substantial portion of the effect size typically associated with treatment interventions. In addition to produce the best evaluations of treatment effects, both control and placebo groups should be included in a double-blind research design using participants who are well familiarized with the study procedures.
Jerry R. Thomas, Karen E. French and Charlotte A. Humphries
In this paper we propose that research in motor behavior has failed to meet the obligation of studying how children learn important sport skills. In particular, understanding the specific sport knowledge base is essential to studying skilled sport behavior. To support this view we review the research in the cognitive area relative to the development of expertise. We then attempt to justify why a similar approach is useful for motor behavior researchers and why they should undertake the study of sport skill acquisition. Finally, we offer a paradigm within which sport skill research might take place.
Thomas J. Romance, Maureen R. Weiss and Jerry Bockoven
This study examined the effectiveness of a specially designed physical education program on the moral development of elementary-age students. Two fifth-grade physical education classes (N = 32) served as control and experimental groups, and participated in identical physical activities during an 8-week program. The experimental group was exposed to special teaching strategies designed to foster moral growth whereas the control group was not. Moral reasoning data were gathered using pre- and posttest interviews. A test of homogeneity of variances on pretest scores revealed that the two intact classes were equivalent on the pretest moral measures. Consequently, a t test was appropriately employed to compare gain scores between the experimental and control groups. T test analyses on the moral reasoning gain scores showed significant differences between the groups in moral growth, with the experimental group showing greater improvement in sport, life, and overall moral reasoning. T tests conducted on within-group changes showed significant pre- to posttest improvement for the experimental group in sport and overall moral reasoning. Concomitant growth did not occur in the control group. These results indicate that a specific program designed to promote moral development through physical education can affect changes in levels of moral growth.
Janice L. Thompson, Melinda M. Manore and Jerry R. Thomas
Studies examining the effects of diet (D) and diet-plus-exercise (DE) programs on resting metabolic rate (RMR) report equivocal results. The purpose of this study was to use meta-analysis to determine if exercise prevents the decrease in RMR observed with dieting. Results from the 22 studies included in this analysis revealed that the majority of studies used female subjects ages 31-45 years, who were fed a relatively low-fat, high-carbohydrate diet of less than 5,023 kJ · day1. The predominant prescribed exercise was aerobic in nature, 31-60 min in duration, performed 4-5 days per week, and of moderate intensity (51-70% of
Jerry R. Thomas, Jack K. Nelson and Gabie Church
Data for the analysis were the health related fitness scores, anthropometric measures, and physical activity information from the National Children and Youth Fitness Study. The subjects were 6,800 boys and 6,523 girls, ages 6 through 18. Multiple regression produced linear composites that were used as covariates to evaluate physical and environmental characteristics that relate to gender differences. The distance runs, chin-ups, and sit-ups displayed similar patterns in gender differences across age. Before puberty the important covariates are mainly physical, namely skinfolds. Following puberty the major factors that reduce gender differences are skinfolds and the amount of exercise done outside of school time.
Jin H. Yan, Richard N. Hinrichs, V. Gregory Payne and Jerry R. Thomas
This study was designed to examine Ihe developmental differences in the speed and smoothness of arm movement during overarm throwing. The second purpose of this investigation was to evaluate whether jerk is a useful measure in understanding children's overarm throwing. Fifty-one girls, aged 3 to 6 years, voluntarily participated in the study. Each subject threw tennis balls as hard as she could toward a large target on the wall. A 2-camera video system was used to obtain 3-D coordinates of the hand and ball using the DLT algorithm. The variables of velocity and jerk (for the hand and ball) served as the movement outcome measures. The age-associated differences in velocity and normalized jerk (absolute jerk standardized relative to movement time and distance) were examined by ANOVAs. The results supported the hypothesis that the older subjects demonstrated faster and smoother hand movements than their younger counterparts during the forward acceleration phase (from the beginning of forward motion to ball release). In addition, the correlation results indicated thai increased hand movement speed was associated with decreased movement jerk in older subjects, whereas increased hand speed was associated with increased jerk in younger subjects. The findings suggest that examining the jerk parameter (normalized or absolute jerk) is a useful and alternative approach to capture the variance of hand movement execution for children's overarm throwing.
Jeffrey S. Hird, Daniel M. Landers, Jerry R. Thomas and John J. Horan
This study compared varying ratios of physical to mental practice on cognitive (pegboard) and motor (pursuit rotor) task performance. Subjects (36 males and 36 females) were randomly assigned to one of six conditions experiencing different amounts of combined mental and physical practice. Seven practice sessions (four trials per session for the pegboard and eight trials per session for the pursuit rotor) were employed. ANOVA results showed that all treatment conditions, except the pegboard control group, showed significant differential pre- to posttest improvement. Furthermore, effect sizes and significant linear trends of posttest scores from both tasks showed that as the relative proportion of physical practice increased, performance was enhanced. In support of previous meta-analytic research, for all treatment groups, the effect sizes for the cognitive task were larger than for the motor task. These findings are consistent with the symbolic-learning theory explanation for mental-practice effects. In addition, the results indicate that replacing physical practice with any mental practice would be counterproductive.