Physical activity intensity can be accurately monitored by smartphone global positioning system 'app'.
Monitoring physical activity is important to better individualise health and fitness benefits. This study assessed the concurrent validity of a smartphone global positioning system (GPS) 'app' and a sport-specific GPS device with a similar sampling rate, to measure physical activity components of speed and distance, compared to a higher sampling sport-specific GPS device. Thirty-eight (21 female, 17 male) participants, mean age of 24.68, s = 6.46 years, completed two 2.400 km trials around an all-weather athletics track wearing GPSports Pro™ (PRO), GPSports WiSpi™ (WISPI) and an iPhone™ with a Motion X GPS™ 'app' (MOTIONX). Statistical agreement, assessed using t-tests and Bland-Altman plots, indicated an (mean; 95% LOA) underestimation of 2% for average speed (0.126 km·h(-1); -0.389 to 0.642; p < .001), 1.7% for maximal speed (0.442 km·h(-1); -2.676 to 3.561; p = .018) and 1.9% for distance (0.045 km; -0.140 to 0.232; p < .001) by MOTIONX compared to that measured by PRO. In contrast, compared to PRO, WISPI overestimated average speed (0.232 km·h(-1); -0.376 to 0.088; p < .001) and distance (0.083 km; -0.129 to -0.038; p < .001) by 3.5% whilst underestimating maximal speed by 2.5% (0.474 km·h(-1); -1.152 to 2.099; p < .001). Despite the statistically significant difference, the MOTIONX measures intensity of physical activity, with a similar error as WISPI, to an acceptable level for population-based monitoring in unimpeded open-air environments. This presents a low-cost, minimal burden opportunity to remotely monitor physical activity participation to improve the prescription of exercise as medicine.
a Discipline of Exercise Physiology, La Trobe Rural Health School , La Trobe University , Bendigo , VIC , Australia.|b Discipline of Exercise Sciences, School of Medical Sciences , RMIT University , Melbourne , VIC , Australia.
Brett Ashley
BA
Gordon
b Discipline of Exercise Sciences, School of Medical Sciences , RMIT University , Melbourne , VIC , Australia.
Lyndell
L
Bruce
b Discipline of Exercise Sciences, School of Medical Sciences , RMIT University , Melbourne , VIC , Australia.
Amanda Clare
AC
Benson
D000328:Adult; D003430:Cross-Sectional Studies; D015444:Exercise / Q000502:physiology*; D005260:Female; D040362:Geographic Information Systems; D006801:Humans; D008297:Male; D018670:Monitoring, Ambulatory / Q000295:instrumentation* / Q000379:methods; D000068997:Smartphone; D055815:Young Adult
GPS; activity monitor; aerobic exercise; smartphone application; validity