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Updated: Feb 14, 2026

Visualization of Intensity Levels to Reduce the Gap Between Self-Reported and Directly Measured Physical Activity
Published on: March 7, 2019
Physical activity levels in urban-based South African learners: A cross-sectional study of 7 348 participants
A Van Biljon1, A J McKune, K D DuBose
1Department of Human Movement Science, Faculty of Science and Agriculture, University of Zululand, KwaDlangezwa, South Africa. vanbiljona@unizulu.ac.za.
Background:
Establishing profiles of physical activity (PA) is critical in tackling the chronic diseases associated with lack of PA and avoiding healthcare costs.
Objective:
To investigate PA levels in urban-based South African (SA) primary school learners.
Methods:
The Physical Activity Questionnaire for Older Children was completed by 7 348 learners (3 867 males and 3 481 females) aged 8 - 14 years, of whom 49% were white, 39% black and 12% from other ethnic groups. Differences in PA levels by ethnic origin and province were determined using an analysis of covariance after adjusting for gender (p<0.05). Bonferroni corrections controlled for multiple comparisons. A fitted regression model examined age-related differences in PA adjusting for province.
Results:
Of SA learners aged 8 - 14 years, 57% (n=4 224) engaged in moderate levels of PA. Thirty-one percent (n=2 247) did not meet internationally recommended amounts of moderate to vigorous physical activity. Overall, males reported higher PA levels than females (p<0.0001). PA levels declined with age from 11 to 14 years by 14% and 20% in males and females, respectively. Black learners had higher PA levels than white learners (p=0.0039). There were also significant differences in PA levels between the provinces (p<0.0001).
Conclusion:
This study provides evidence of differences in PA levels between gender, age and ethnic groups, and between provinces. A targeted approach to increase PA in high-risk populations in SA is warranted. Increased PA will help reduce the risk of chronic diseases and will contribute to the health of SA's population and the growth of the country's economy.
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