Katherine T. Thomas

Strategies for improving understanding of motor expertise [or mistakes we have made and things we have learned!!]

Publisher Summary This chapter represents the consensus on a number of issues related to motor expertise research. The chapter overviews the existing state of knowledge on motor expertise through discussion of the historical origins of motor expertise research, identification of contemporary areas of research focus, description of the prototypic motor expertise studies, and assessment of the degree of generalizability possible from the existing knowledge base. The strategies for improving/modifying paradigmatic approaches to the study of motor expertise are examined by discussing the necessity to recognize the limitations within the use of recipient paradigms, to value situation specificity and ecological validity, and to link studies of motor expertise to contemporary theories of motor control and learning. Alternatives to traditional cross-sectional research designs and to “one-off” research studies are described as strategies for improving methodological approaches to the study of motor expertise. The chapter deals with strategies for improving the measurement of motor expertise, highlighting existing anomalies in the definition of experts, in the formation of control groups, and in the use of uni-dimensional forms of performance measurement.

The Development of Sport Expertise: From Leeds to MVP Legend

The contributions of motor skill and cognition (decision making and knowledge) to sport performance change across age, expertise, and sports. Knowing how to execute a skill is a prerequisite for efficient and effective execution. As skill execution improves, the cognitive aspects of motor execution become automated. For low-strategy sports (e.g., swimming) variables such as physical size and ability combine with motor skill to determine expertise. In highstrategy sports (e.g., basketball) cognition remains an important variable in game performance. The performer must know what to do and then be able to execute the plan. Knowledge and decision making should not limit the development of expertise. Specific strategies for coaches and teachers may facilitate the development of expertise in children and adolescents.

Development of Gender Differences in Physical Activity.

The development of gender differences in physical activity was reviewed using the categories of motor performance, motor activity, physical activity, and health related physical fitness. Gender differences in motor performance were related to age in 12 of 20 tasks, resulting in three types of developmental curves. Most differences are suggested as being environmentally induced prior to puberty but influenced by a biology–environment interaction after puberty. The level of motor activity is higher in boys even in infancy, and gender differences increase across childhood and adolescence. This suggests that heredity influences initial differences but interacts with environmental circumstances as children grow and develop. Boys from several countries are observed to be more physically active than girls, probably accounting in part for their better performance on physical fitness tests. Boys perform better than girls on three of the four measures of health related physical fitness: mile run, chin-ups, and sit-...

Ethnic and age trends for body composition in women residing in the U.S. Southwest : I. regional fat

This study assessed body density (BD) in an ethnically diverse sample of women (African American, Caucasian, Mexican American and Native American) (N = 139) who were between 20 and 30 or 40 and 50 yr of age and of normal weight for their height. BD was assessed using three methods: hydrostatically determined density (UWW), total body potassium (TBK) and the Jackson et al. (1980) sum of seven SF with gluteal circumference (SF). Ethnic differences in BD were detected by TBK and UWW. BD from SF did not detect ethnic differences, and the SEE was unacceptable. Based on multiple regression, the prediction equation was: BD = 1.1197794 - 0.000224382 (X3) + 0.006999 (e2) - 0.000320177 (X2) - 0.001892 (e1) + 0.001750 (e3) - 0.000537005 (x1) (where x1 = gluteal C, x2 = age in years, x3 = sum of 7 SF and e1, e2, and e3 describe ethnicity). This formula had a reduced SEE, a higher correlation with hydrostatically determined BD, and was sensitive to ethnic differences detected with other measures of BD. A 24-mmol decrease in potassium was found when comparing the older Caucasian women with the younger Caucasian women, while the difference for the African, Mexican, and Native American groups was 200-300 mmol.

Age Differences in use of Strategy for Recall of Movement in a Large Scale Environment

Abstract In order to investigate how children remember distance (route) and location (landmark) information, two experiments were conducted in a large scale environment using jogging as the means of locomotion. In Experiment 1, thirty 4-year-old and thirty 9-year-old children were randomly assigned within age to three groups which were cued prior to the jog to remember the event, location of the event or distance to the event. Results indicated that older children reproduced the location and distance better than younger children. Cueing children to remember the location resulted in more accurate estimates than the other conditions. In Experiment 2, 5-year-old, 9-year-old, and 12-year-old children (24 children of each age) were randomly divided into step counting strategy and control groups, and asked to reproduce a criterion distance jogged. Results indicated that the three strategy groups and the 12-year-old controls estimated distance with similar accuracy, but the 9- and 5-year-old controls were differ...

Principles of Motor Development for Elementary School Physical Education

Four principles are drawn from approximately 100 years of research in the area of motor development. The principles are (1) children are not miniature adults, (2) boys and girls (children) are more alike than different, (3) good things are earned, and (4) no body (nobody) is perfect. Five sections of this article introduce some of the major assertions warranted by that research organized around the principles. The sections are Physical Growth and Maturation, Motor Skills, Physical Activity, Psychological Factors, and Developmental Skill Acquisition. Quality physical education programs are evidence based; thus when observing such programs one can see the principles in action. The result is a developmentally appropriate program based on the 3 characteristics of developmentally appropriate physical education: children are more alike than different, children progress through the same stages of development in the same order, and the rate of those developments varies among children.

Developmental Gender Differences for Overhand Throwing in Aboriginal Australian Children

In a review of 46 meta-analyses of gender differences, overhand throwing had the largest gender difference favoring boys (ES > 3.0). Expectations for gender-specific performances may be less pronounced in female Australian Aborigines, because historical accounts state they threw for defense and hunting. Overhand throwing velocities and kinematics were recorded in 30 female and male Aboriginal Australian children 6-10 years old. Results indicated the Aboriginal girls and boys were more similar in horizontal ball velocities than U.S. girls and boys. Throwing kinematics between girls and boys were also more similar in Australian Aborigines than U.S. children. Aboriginal girls threw with greater velocities than U.S., German, Japanese, and Thai girls, while the boys were similar across cultures.

Is There a General Motor Program for Right Versus Left Hand Throwing in Children

The purpose of this study was to determine if a general motor program controlled some or all aspects of overhand throwing. Using a 12 camera Vicon motion analysis system to record data from body markers, a group of 30 Australian Aboriginal children 6-10 years of age threw with maximal effort into a large target area. Data were reduced and analyzed for numerous variables and correlations were calculated between dominant and non-dominant side variables that were deemed reliable. Results indicated that five variables showed significant dominant to non-dominant correlations. However, only two of the five were entered into both multiple regressions to predict horizontal ball velocity for the dominant vs. non-dominant sides. The variables entered suggested that more gross aspects of the movement (stride distance and pelvis flexion) were both correlated from dominant to non-dominant sides and predicted horizontal ball velocity. Thus, the general motor program does not appear to control the more complex and coordinated parts of the throwing motion.

What Is Motor Development: Where Does It Belong?

Four questions are presented: What are the historical roots of motor development; How can motor development be characterized; How should motor development be conceptualized; and How should motor development be organized? A brief history presents the psychological roots of motor development and emphasizes the individual researchers who have created the area of motor development since the 1960s. Motor development is characterized as a composite of the researchers, knowledge, application of knowledge, systems for delivering knowledge, and graduate programs in motor development. Motor development should be a perspective rather than a structure or subdiscipline. All courses in human movement should be taught from a developmental perspective, research should be done within the appropriate subdiscipline, and some of that research should be developmental. Motor development will be best served if researchers align with scientists within the subdisciplines and share developmental information in cross-disciplinary g...

Sedentary behavior and physical activity predicting depressive symptoms in adolescents beyond attributes of health-related physical fitness

Background Sedentary behavior (SB), physical activity (PA), and attributes of physical fitness have been shown to be related to depressive symptoms in adolescents. The purpose of the present study was to investigate whether SB and fitness-producing activity predicted depression in active adolescents over and above gender and fitness attributes. Methods Participants were 249 adolescents (age: 12.85 ± 0.89 years, mean ± SD) from 3 public middle schools who wore Actical accelerometers to assess their SB and PA. Participants also completed the FITNESSGRAM health-related fitness assessment and a brief depression questionnaire. A 3-step hierarchical regression analysis was conducted with gender and fitness attributes (i.e., body mass index (BMI), maximal volume oxygen uptake (VO2max), curlups, and pushups), moderate- and vigorous-intensity activity, and SB entered in respective steps. Results Regression analysis indicated activity variables (i.e., moderate- and vigorous-intensity activity) significantly predicted depression (ΔR2 = 0.12, p < 0.01) beyond gender and fitness attributes. Overall, gender, fitness attributes, activity variables, SB explained 31% of the variance in depression. Structure coefficients revealed VO2max (rs = −0.77), moderate-intensity activity (rs = −0.67), vigorous-intensity activity (rs = −0.81), and SB (rs = 0.57) were substantially correlated with the criterion variable; thus, they were the strongest predictors of depression. Conclusion The findings of the current study indicated SB and PA were both significant predictors of depression; however, sufficient fitness-producing activity and adequate cardiorespiratory fitness may nullify the negative influence of SB on depressive symptoms in active adolescents.