@article{ref1,
title="Reliability and validity of a GPS-enabled iPhone(TM) "app" to measure physical activity",
journal="Journal of sports sciences",
year="2015",
author="Benson, Amanda Clare and Bruce, Lyndell and Gordon, Brett Ashley",
volume="33",
number="14",
pages="1421-1428",
abstract="This study assessed the validity and reliability of an iPhone(TM) &quot;app&quot; and two sport-specific global positioning system (GPS) units to monitor distance, intensity and contextual physical activity. Forty (23 female, 17 male) 18-55-year-olds completed two trials of six laps around a 400-m athletics track wearing GPSports Pro(TM) and WiSpi(TM) units (5 and 1 Hz) and an iPhone(TM) with a Motion X GPS(TM) &quot;app&quot; that used the inbuilt iPhone(TM) location services application programming interface to obtain its sampling rate (which is likely to be ≤1 Hz). Overall, the statistical agreement, assessed using t-tests and Bland-Altman plots, indicated an underestimation of the known track distance (2.400 km) and average speed by the Motion X GPS(TM) &quot;app&quot; and GPSports Pro(TM) while the GPSports WiSpi(TM) device overestimated these outcomes. There was a ≤3% variation between trials for distance and average speed when measured by any of the GPS devices. Thus, the smartphone &quot;app&quot; trialled could be considered as an accessible alternative to provide high-quality contextualised data to enable ubiquitous monitoring and modification of programmes to ensure appropriate intensity and type of physical activity is prescribed and more importantly adhered to.<p /> <p>Language: en</p>",
language="en",
issn="0264-0414",
doi="10.1080/02640414.2014.994659",
url="http://dx.doi.org/10.1080/02640414.2014.994659"
}