Purpose: The purposes of this study are to assess the reliability of the physical activity components of the Canada Fitness Survey (CFS) questionnaire (N = 64 males, N = 63 females) and the Canadian Aerobic Fitness Test (N = 44 males, N = 52 females) in a sample of subjects between 15 and 80 yr.
Results: The intraclass correlation (rI) for the fitness scores was 0.98. The activity variables showed low to moderate correlations (rI = 0.48-0.53). Correlations were higher for males (rI = 0.38-0.65) than females (rI = 0.28-0.60) for most of the activity variables reported. Males generally report leisure activity more reliably than nonleisure activity, whereas the opposite was true for females. Males reported strenuous activity with higher reliability (rI = 0.86) than females (rI = 0.31). There was considerable variation in the reliability of specific activities. Of the components of physical activity (time, intensity, duration) that comprise the energy expenditure (EE) variable, the least reliably reported is intensity for both males (rI = 0.43) and females (rI = 0.55).
Conclusions: The CFS questionnaire is moderately reliable for most measures of physical activity. Estimates of reliability vary considerably among the various activities and components of these activities and between males and females.