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Ralph Maddison, Yannan Jiang, Steve Vander Hoorn, Cliona Ni Mhurchu, Daniel Exeter and Jennifer Utter

Background:

Research in adults shows poor agreement between self-reported and objectively measured proximity to physical activity resources; however there is little such research in adolescents. This study assessed the level of agreement between self-reported and objective measures of distance to physical activity resources in adolescents; and whether perceived or actual distance was related to actual use and physical activity levels.

Methods:

110 New Zealand high school students (12−18 years) were asked the time (in minutes) it would take them to walk from their home to the nearest physical activity resource, and whether they had used it in the previous month. The distance from participants’ homes to the nearest resource was measured using GIS. Physical activity was assessed with accelerometers.

Results:

Agreement was poor, with weighted Kappa Indices ranging from 0.1 to 0.4. The facilities used most frequently were schools (90%), public parks (76%), and playing fields (74%). Closer location was associated with higher use of some facilities only. Moderate-to-vigorous activity levels were not associated with self-reported or measured distance.

Conclusions:

Agreement between perceived and measured access is poor among adolescents. Further research is needed to understand how individual and social factors interact with environmental factors and whether improving awareness improves use.

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Ralph Maddison, Yannan Jiang, Stephen Vander Hoorn, Daniel Exeter, Cliona Ni Mhurchu and Enid Dorey

This study aimed to describe the location and intensity of free-living physical activity in New Zealand adolescents during weekdays and weekend days using Global Positioning Systems (GPS), accelerometry, and Geographical Information Systems (GIS). Participants (n = 79) aged 12–17 years (M = 14.5, SD 1.6) recruited from two large metropolitan high schools each wore a GPS watch and an accelerometer for four consecutive days. GPS and accelerometer data were integrated with GIS software to map the main locations of each participant’s episodes of moderate-vigorous physical activity. On average participants performed 74 (SD 36) minutes of moderate and 7.5 (SD 8) minutes of vigorous activity per day, which on weekdays was most likely to occur within a 1 km radius of their school or 150 meters of their home environment. On weekends physical activity patterns were more disparate and took place outside of the home environment. Example maps were generated to display the location of moderate to vigorous activity for weekdays and weekends.

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Ralph Maddison, Cliona Ni Mhurchu, Andrew Jull, Yannan Jiang, Harry Prapavessis and Anthony Rodgers

This study sought to quantify the energy expenditure and physical activity associated with playing the “new generation” active and nonactive console-based video games in 21 children ages 10–14 years. Energy expenditure (kcal) derived from oxygen consumption (VO2) was continuously assessed while children played nonactive and active console video games. Physical activity was assessed continuously using the Actigraph accelerometer. Significant (p < .001) increases from baseline were found for energy expenditure (129–400%), heart rate (43–84%), and activity counts (122–1,288 versus 0–23) when playing the active console video games. Playing active console video games over short periods of time is similar in intensity to light to moderate traditional physical activities such as walking, skipping, and jogging.