Physical activity in the lives of Hong Kong Chinese children

To understand the physical activity culture in the lives of Hong Kong Chinese children and their parents, 48 young people between the ages 9 and 16 and their parents, with different socio-economic backgrounds and geographical locations, were interviewed for this study. By applying Confucianism and postcolonialism, this study aimed to investigate the meaning of physical activity in the lives of Hong Kong children and their parents. The results showed that parents value physical activity as a factor which contributes to their children's well-being and provides balance to their life. There were differences though, in this attitude, for different age groups. Junior students (aged 9–12) expressed their interest in physical activities. However, older students (12 or above) in secondary school, think or are told that academic study is the most important aspect of their life and that physical activities are not a priority. When examining parents' and children's involvement in physical activity, the barriers to the parents' involvement in their children's physical activities included lack of time and a habitual sedentary lifestyle at home.     

Force-Time Curves of Voluntary Muscular Contraction at Varying Tensions

Abstract

A recording spring-loaded hand ergograph with fast moving paper was utilized to obtain a record of the entire hand contraction sequence. The subjects (N=40) were given a series of six contractions, each beginning at a different initial tension: 0, 10, 15, 20, 25, and 30 kilograms. The contractions were separated by one minute and the order was systematically rotated to minimize either learning or fatigue. The development of force was found to progress exponentially according to a three-component mathematical equation. The control group (zero pre-tension) achieved a greater maximal force (F=4.5) than all others, and was the only one with a clear advantage in speed and tension. The rate of change constants were comparable, but the early initial (negative) component disappeared at the 20 kilogram condition and beyond. The factor of rate seemed to be independent of tension level.     

A Comparison of Autonomic Nervous System Activity between Physically Trained and Untrained Individuals

Abstract

The study is concerned with the comparison of autonomic nervous system (ANS) activity between highly trained collegiate track and field athletes and untrained individuals. An ANS test battery consisting of six individual measures of autonomic activity was used: (a) sublingual temperature, (b) salivary output, (c) volar skin resistance, (d) palmar skin resistance, (e) diastolic blood pressure, and (f) heart period. One group of athletes, track runners, were found to have a mean autonomic balance score significantly higher (at the .02 level) than the norm group of college students. The autonomic scores of field event athletes, however, were not significantly different from the norm. An analysis of the type of ANS activity demonstrated by the runners showed a dominance by the parasympathetic as compared to a mixed pattern demonstrated by the normative sample. It was concluded that highly trained track runners demonstrated a significantly higher autonomic balance score than did normal college students, and that their resting autonomic pattern was predominantly parasympathetic. There was evidence to indicate that equality of performance in the running events in track, and possibly other athletic events, may be partially predictable from autonomic balance scores.     

Effect of Divided Attention on Children's Rhythmic Response

Abstract

The purpose of this study was to examine the role of selective attention in rhythmic response of children. A motor rhythmic response of grade 2 (N = 30) and grade 4 (N = 29) boys was examined with respect to the sensory modality of a secondary stimulus input. It is thought that the information processing capacity of children, as manifested in the processes of selective attention, may be a factor in the developmental changes in motor skill learning and performance. Using a rhythmic analysis system, subjects in each grade level performed ten blocks of five trials in one of three groups: control, audio interference, and visual interference. Output from a dual-channel recorder was scored to give time and space errors (AE and CE). Performance variation (VE) was calculated from the error scores. Multivariate analysis of variance revealed significantly better performance by the grade 4 subjects. The treatment conditions did not significantly impair performance as measured by CE error scores. The audio input resulted in significantly less consistent temporal performance (VE).