Physical Activity Assessment-Self-Reported Versus Pedometer-Measured, and Associations with Health Markers Among University Students in South Africa.

Accurate measurement of physical activity is crucial for promoting health and preventing non-communicable diseases, particularly in Sub-Saharan Africa, where the dual burden of infectious and chronic diseases presents significant public health challenges. While self-reported tools are commonly used, they are often limited by recall and social desirability biases. This study aimed to compare self-reported physical activity with objectively measured pedometer data and explore their associations with fitness and anthropometric indicators among university students. A cross-sectional study was conducted among 60 full-time students at a South African university. The study was conducted in two phases: For phase 1, participants completed the International Physical Activity Questionnaire (IPAQ). For phase two, participants wore pedometers for seven consecutive days to measure total and aerobic step counts. Fitness was assessed using the Harvard Step Test to calculate the Physical Efficiency Index (PEI), and anthropometric data (BMI, waist-to-hip ratio, body fat percentage) were recorded. Statistical analyses included Spearman's correlations, Mann-Whitney U test, Kruskal-Wallis H test, and multivariable linear regression. While 83.3% of participants self-reported high physical activity levels, pedometer data indicated that 61.7% accumulated fewer than 1500 aerobic steps per day and 53.3% recorded fewer than 5000 total steps. No significant association was found between self-reported activity and pedometer-measured steps (