Physical activity and fitness measures in New Zealand : a study of validation and correlation with cardiovascular risk factors

Abstract

The primary aim of the study was to validate the short and long form of the recently-created NZ physical activity questionnaires (NZPAQ-SF and NZPAQ-LF, respectively) in a multi-ethnic sample in Auckland. An international physical activity questionnaire (IPAQ-long) was also validated and compared to the NZ instruments. Objective PA measures were used to create a NZ compendium of PA intensities, providing baseline data for culturally-specific PAs. Secondary aims included an examination of the relationship between PA and CRF, and their associations with cross-sectional measures of cardiovascular (CV) risk factors. The study sample consisted of 186 apparently healthy males (n=90) and females (n=96) aged 19-86 yrs, classified as European/Other (n=60), Māori (n=61), and Pacific (n=65). Heart rate monitoring (HRM) with individual calibration was used to objectively measure the duration, frequency, and intensity of at least moderate-intensity PAs performed over 3 consecutive days. Type of PA and the context in which it was performed was simultaneously recorded by participants on daily PA logs. Correlations between HRM and self-reported levels of brisk walking, moderate-intensity, vigorousintensity, were poor for each questionnaire, and correlations were lower for Māori and Pacific ethnic groups than for European/Other. The NZPAQ-SF (r=0.3, p<0.001) and NZPAQ-LF (r=0.3, p<0.001) performed better than the IPAQ-long (r=0.1, p=0.37). The culturally-specific list of PA intensities showed strong correlation (R2=0.68) to an internationally-accepted compendium of PA intensities, and provided baseline energy cost data for 13 PAs performed by Māori and Pacific people in NZ. CRF levels were primarily influenced by gender, ethnicity, obesity, and performing at least 15 min/day of vigorous-intensity PA, and showed stronger associations with fasting blood lipids and glucose, while PA was more strongly related to SBP and DBP. The validated NZPAQs are acceptable for measuring population level PA prevalence in NZ adults, although accuracy is lower for Māori and Pacific people. However, the availability of a culturallyspecific list of PA intensities could potentially increase the accuracy of self-reported PA by Māori and Pacific people. Results from this study highlight the importance of vigorous-intensity PA for CV health, and identifies NZ Pacific people as high risk in terms of PA, obesity, and CRF.