Comparing the Validity of a GPS Monitor and a Smartphone Application to Measure Physical Activity

Abstract

Background: A recent approach to increasing physical activity levels, managing weight and improving health has been via technological advances, such as the Web 2.0 technologies, wearable activity trackers and smartphones. These approaches might be effective due to reduced cost, userfriendly environment and real-time feedback provided. Many of these monitors and smartphone applications are marketed to provide personal information on the level of physical activity, however little or no information is available regarding their validity.Aims: The purpose of this study was to compare the criterion validity for distance travelled and total energy expenditure (TEE) between a commercially available GPS monitor, Garmin Forerunner 310XT, and a freeware GPS application for Android smartphones, Runkeeper, under semistructured activity settings.Methods: A single, healthy and physically active participant took part in all trials. The same protocol was repeated on 40 occasions (20 walking and 20 running sessions). The participant wore the Garmin GPS on the left wrist and a smartphone with the Runkeeper application activated on the left arm. Distance was compared against an objectively measured distance with three different methods and energy expenditure estimates for each monitor was evaluated relative to criterion values concurrently obtained from the portable metabolic system Cosmed K4b2. Differences from criterion measures were expressed as a mean absolute percent error and were evaluated using repeated measures ANOVA and Bland-Altman plots.Results: For overall group comparisons, the mean absolute percent error values for distance were 0.30% and 0.74% for Garmin (walking and running), while higher values were calculated for Runkeeper (3.28% during running and 4.43% during walking), which significantly overestimated distance in both conditions. For energy expenditure estimation, significant differences were observed for both monitors (pB0.001). Garmin significantly underestimated energy expenditure compared to the criterion method in both conditions by 17%, while Runkeeper significantly overestimated it by 6.29% during running and 35.52% during walking.Conclusions: The present study offers initial evidence for the validity of GPS technology of wearable activity monitors and smartphone applications for measuring distance travelled. However, estimates of energy expenditure were poor, except for Runkeeper during running which provided acceptable error.

A Comparison of a Smartphone App with Other GPS Tracking Type Devices Employed in Football

“…With ever-evolving smartphone applications and the increase in GPS tracking technology being used in sport, an analysis of a smartphone application and comparison with a range of GPS tracker devices currently used in sport was warranted. The use of smartphone technology to measure physical activity is nothing new as there has been objective studies that support the use of in this way and reported that these were reliable and valid [40,41]. The major findings of this study support studies that reported that a smartphone application can reliably monitor physical activity [42,35].…”

Validity and Reliability of Mobile Applications for Assessing Strength, Power, Velocity, and Change-of-Direction: A Systematic Review

“…Overall, 11 different apps were tested, in which [ 15 , 19 , 28 , 32 , 37 , 42 ] studies were conducted using the My Jump and My Jump App 2, [ 17 , 18 , 27 , 30 , 34 , 38 , 44 , 46 ] the Powerlift, previously named Mylift, [ 36 ] the Ergo Arm Meter, [ 35 ] the Smartphone accelerometer, [ 33 , 41 ] the Speedclock App, [ 31 ] the MySprint App, [ 29 , 45 ] the ILoad, and [ 26 ] the Styrd App.…”

“…For the My Jump App and My Jump App 2, the ICC values of reliability were from 0.492–0.999 and CV values were between 3.4% and 12% [ 15 , 19 , 32 , 37 , 42 ]. For the PowerLift and My Lift App, the ICC values of reliability were 0.70–0.989 [ 17 , 18 , 27 , 30 , 44 , 45 ] and CV values were between 3.97% and 10.4% [ 17 , 27 , 30 , 34 , 44 ]. For the Ergo Arm Meter, the SEM value of reliability was <13.1º/s [ 36 ].…”

“…Various parameters are measured by practitioners under physical conditions [ 3 , 34 ]. For example, it is used to measure balance [ 43 ], distance [ 44 ] and physical activity [ 45 ]. In addition, it has been reported in the research that the use of mobile applications increases the level of physical activity by increasing the level of physical fitness [ 46 ].…”

Economic Implications of Smartphone Applications Promoting the Physical Activity

“…There is a very few information available about the validity of the data logged by the smartphone applications or wearable trackers since the sensors of the mobile devices are rarely tested for accuracy related to the physical activity records. Some studies, like [6], are showing reliable measures for distance while the energy expenditure estimation was low or even not very accurate at all compared with results coming from the medical devices. Technology can help to integrate physical activity into the health care standard by recommending the proper exercises to individuals based on the health records.…”