Exploring the Relationship Between Planned and Performed Physical Activity in University Students: the Utility of a Smartphone App (Preprint)
BACKGROUND Mobile device technology has been forwarded as a popular method of collecting physical activity and time use data. However, few studies have examined day-level plans to be physically active and subsequent physical activity behavior, likely due to the feasibility of collecting this data. OBJECTIVE The purpose of this study was to test the feasibility and acceptability of a new mobile phone application (Life in a Day App: LIAD) for collecting real-time time-use data among college-aged students and to examine whether plans to be physically active (recorded in advance on an electronic calendar for the protocol period) were associated with objectively-assessed physical activity during the study protocol (measured by accelerometry). METHODS Forty-eight participants were randomly assigned to one of three protocols defined by the number of days of data collection (1, 3, or 5 days). Participants were asked to record their planned activities for the protocol period in a Google calendar and were provided with smartphones (Samsung Galaxy S5) with the LIAD application to complete time-use entries in real time among a set of categories (e.g., exercise/sports, eating/cooking, school, personal care). Participants were instructed to wear an accelerometer (ActiGraph wGT3X+) on their non-dominant wrist during the protocol period (i.e., 24 hours a day) in order to objectively measure physical activity. From the 48 participants, there was a total of 144 days of protocol data collected. RESULTS Overall compliance with the protocol was very high with all participants utilizing the LIAD app. Out of 144 days, 122 days of protocol data were eligible for analysis. Most participants did not plan nor participate in physical activity (76 days, 61% of total days). Activity was not planned but occurred on 17 days (14%). Activity was planned but did not occur on 18 days (15%), while activity was planned and MVPA occurred on 12 days (10%). No differences were found by sex. Activities related to screen time most often replaced planned physical activity, while unplanned physical activity most often related to active transport. The most commonly reported issues were carrying two smartphones and remembering to record activities on the LIAD application in real time. CONCLUSIONS Overall, there was moderate congruence between plans to be physically active and executed physical activity. Despite a few challenges, the LIAD app is a reasonable and practical method of collecting real-time time use data and offers insight into the relationship between planned vs. executed exercise at the day-level.