Dorita Du Toit

Relationship between physical fitness and academic performance in South African children

The application of the scientific method in sport demands that regular and standardised testing must be implemented by the coach or scientist to determine whether the intervention, for instance training, has had the desired effect on sporting performance. However, the test administered by the coach or scientist must have been rigorously evaluated for acceptable validity and reliability. Moreover, the judgment as to the validity of a test must not be influenced by the popularisation of a test. Despite scientific evidence to the contrary, a popular incremental field test for endurance athletes (Conconi Test) has been uncritically accepted as valid by some coaches and sport scientists. The Conconi Test is assumed a non-invasive measure of the anaerobic threshold through the identification of a coincident deflection in heart rate. This paper briefly considers the methodology and biological explanation for the Cononic Test. The paper also elaborates on the historical context within which the popular Conconi Test was developed and how factors other than scientific evidence have led to the popularisation of this test amongst sport scientists and coaches. Users of this test should consider the possibility that at least some part of the accepted validity of the Conconi Test was due to appeals to authority (eminent scientists, prominent athletes, magnitude of the feat, medal counts, records), popularity and coincidental correlation (performance and test result).

The relationship of overweight and obesity to the motor performance of children living in South Africa

Abstract Objectives: This study aimed to determine the relationship between overweight and obesity and the motor performance of nine- to 13-year-old South African children. Design: The study used a one-way cross-sectional design based on baseline measurements. Settings and subjects: The research group comprised 280 Grade 4, 5 and 6 learners (128 boys and 152 girls) from two schools that represented a distribution of socio-economic status, race and gender. Outcome measures: Anthropometric [(body mass index (BMI) and fat percentage] and motor performance measurements (fine manual control, manual coordination, body coordination and strength and agility) were obtained by means of the Fitnessgram and the Bruininks-Oseretsky Test of Motor Proficiency-II. International age-specific cut-off points were used to classify the childrens body composition as normal weight, overweight or obese. Data were analysed by means of descriptive statistics, correlation matrices and analysis of variance, followed by a Tukey post hoc analysis. Results: The results showed that running speed and agility decreased significantly with an increase in BMI. Muscular strength also decreased significantly with a smaller practical significance, while fine manual control, manual coordination, and body coordination showed the weakest relationship to BMI. Analysis of variance showed significant relationships between BMI and running speed and agility (p-value < 0.05). These relationships were influenced differently by gender and ethnicity. Conclusion: The motor performance of young South African children was negatively influenced by overweight and obesity. Intervention strategies are recommended to reduce the consequences of overweight and obesity in the overall development of such children.

The effects of an enhanced quality Physical Education programme on the physical activity levels of Grade 7 learners in Potchefstroom, South Africa

Background: The absence of Physical Education (PE) from the South African school curriculum before its reintroduction in recent years contributed to health concerns regarding the low physical activity (PA) levels of children and adolescents in South Africa. Purpose: This study evaluated the effects of a once-a-week enhanced quality PE programme on the PA levels of South African Grade 7 learners. Methods: Using a pre-test and post-test control-group design, 110 Grade 7 learners aged 12–13 years (experimental school, n = 40; control schools, n = 70) from two primary schools in Potchefstroom, South Africa, were studied. They participated in a 12-week PE intervention programme based on the guidelines of the South African Curriculum and Assessment Policy Statement, which allocates one hour per week to PE teaching. The intervention included five quality-enhancing components, namely well-trained teachers, homework activities, a reward system, hand-made apparatus and the monitoring of activity intensity. In the experimental school, 40 learners were randomly assigned from the total Grade 7 class (n = 124) to the experimental group, while two control groups (n = 37 and n = 33) were used, one from the same school as the experimental school and the other from a different school. Additionally, to control for PE teacher interaction effect, the experimental group was divided into 4 experimental sub-groups of 10 learners each, which were taught by 4 different PE teachers, and the pre-test and post-test data of these experimental sub-groups were also analysed. Childrens PA levels were measured before and after the intervention using a validated Childrens Leisure Activities Study Survey questionnaire. The Kruskal–Wallis and Wilcoxon signed-rank tests were used to evaluate the effects of the intervention programme. Results: No significant differences were found within the experimental group between the 4 experimental sub-groups and between the 2 control groups at pre- and post-test measurements (p > .05). There was a significant effect for the experimental group as a whole, as results of the total experimental group showed statistically significant increases in moderate PA (ES = 0.47; p = .014), vigorous PA (ES = 0.48; p = .012) and total PA (ES = 0.51; p = .008) as well as decreases in sedentary behaviours (ES = 0.39; p = .041) after the 12-week intervention programme, whereas no significant changes were found in the control group. Statistically significant improvements were also found in all 4 experimental sub-groups between pre- and post-tests for the time spent in moderate PA (p = .028–.05; ES = 0.23–0.64), vigorous PA (p = .018–.036; ES = 0.23–0.63), total PA (p = .017–.05; ES = 0.30–0.68) and sedentary time (p = .014–.049; ES = 0.26–0.66), whereas no marked changes were observed among the two control groups, indicating no PE teacher interaction effect on the results. Conclusions: The enhanced quality PE programme can be used as a valuable framework for PE implementation targeted at promoting learners’ PA levels, even in the presence of restricted time allocation, and limited teaching and learning resources.