Towards a Functional Approach to the Assessment of Daily Life Physical Activity in Children: Are the PAQ-C and Fitbit Flex-2 Technically Adequate?

Considering the need for functional physical activity (PA) measures in PA settings, this study sought to determine the technical adequacy of the Physical Activity Questionnaire for Older Children (PAQ-C) and the Fitbit Flex-2, two instruments with promising features for wide use, using the Actigraph GT3X+ accelerometer as the criterion reference. A total of 218 Greek children (94 boys, 124 girls; mean age = 10.99 ± 1.52 years) volunteered to join in. Participants wore the PA trackers for seven days and completed the PAQ-C. Moreover, a sub-group (n = 60) recompleted the PAQ-C after a week. Results revealed acceptable internal consistency and excellent test-retest reliability for the PAQ-C. Regarding concurrent validity, weak to moderate correlations with PA parameters recorded by the GT3X+ were revealed for the total PAQ-C and were excellent for the Flex-2, while a Bland-Altman plot indicated good agreement. Finally, in alignment with relevant literature, significant gender, but no age, differences were found in participants' PA records in all the tools applied. The above results support the use of the PAQ-C and the Fitbit Flex-2 in children. Considering that they shed light into different parameters of children's habitual PA, their combined utilisation, providing comprehensive information, is strongly recommended.

Physical Activity and Sedentary Behaviors of Young Children: Trends from 2009 to 2018.

Over the last decade, the lives of children in several countries, including Greece, have been affected by recession. The aim of the present study was (a) to examine time trends in physical activity (PA) and screen time (ST) of Greek preschool children, together with their family affluence (FA), from 2009 until 2018, and to explore the associations among them; and (b) to investigate the connections of parental educational level and children's BMIs to their achieving ST (<1h/day) and PA (11,500 steps/day) guidelines. A total of 652 children from four cross-sectional cohorts participated. PA was recorded with Omron HJ-720IT-E2 pedometers, whereas ST, family affluence (FA) and parental educational level were reported by participants' parents. The results of the one-way ANOVAs that were computed revealed statistically significant differences among cohorts, albeit of no practical importance, in PA, ST and FA. According to the regressions calculated, neither BMI nor the educational level was related to membership in ST and PA guidelines groups. ST was a significant predictor of children's PA in all week periods (school-time, leisure-time, weekend), whereas FA was not such a strong predictor. Multilevel interventions aiming at both ST and PA seem to be imperative for the benefit of young children's health.