B-MOBILE - A Smartphone-Based Intervention to Reduce Sedentary Time in Overweight/Obese Individuals: A Within-Subjects Experimental Trial

Abstract

PurposeExcessive sedentary time (SED) has been linked to obesity and other adverse health outcomes. However, few sedentary-reducing interventions exist and none have utilized smartphones to automate behavioral strategies to decrease SED. We tested a smartphone-based intervention to monitor and decrease SED in overweight/obese individuals, and compared 3 approaches to prompting physical activity (PA) breaks and delivering feedback on SED.Design and MethodsParticipants [N = 30; Age = 47.5(13.5) years; 83% female; Body Mass Index (BMI) = 36.2(7.5) kg/m2] wore the SenseWear Mini Armband (SWA) to objectively measure SED for 7 days at baseline. Participants were then presented with 3 smartphone-based PA break conditions in counterbalanced order: (1) 3-min break after 30 SED min; (2) 6-min break after 60 SED min; and (3) 12-min break after 120 SED min. Participants followed each condition for 7 days and wore the SWA throughout.ResultsAll PA break conditions yielded significant decreases in SED and increases in light (LPA) and moderate-to-vigorous PA (MVPA) (p<0.005). Average % SED at baseline (72.2%) decreased by 5.9%, 5.6%, and 3.3% [i.e. by mean (95% CI) −47.2(−66.3, −28.2), −44.5(−65.2, −23.8), and −26.2(−40.7, −11.6) min/d] in the 3-, 6-, and 12-min conditions, respectively. Conversely, % LPA increased from 22.8% to 26.7%, 26.7%, and 24.7% [i.e. by 31.0(15.8, 46.2), 31.0(13.6, 48.4), and 15.3(3.9, 26.8) min/d], and % MVPA increased from 5.0% to 7.0%, 6.7%, and 6.3% (i.e. by 16.2(8.5, 24.0), 13.5(6.3, 20.6), and 10.8(4.2, 17.5) min/d] in the 3-, 6-, and 12-min conditions, respectively. Planned pairwise comparisons revealed the 3-min condition was superior to the 12-min condition in decreasing SED and increasing LPA (p<0.05).ConclusionThe smartphone-based intervention significantly reduced SED. Prompting frequent short activity breaks may be the most effective way to decrease SED and increase PA in overweight/obese individuals. Future investigations should determine whether these SED reductions can be maintained long-term.Trial Registration ClinicalTrials.gov NCT01688804

Acceptability of smartphone technology to interrupt sedentary time in adults with diabetes

“…Several other trials have demonstrated promise in reducing sedentary time among office workers using various interventions that include computer software [26], computer software and text messages [30], sit-stand workstations [23,31], portable pedal bike [24], or an in-person session [32]. Furthermore, the magnitude of changes in sedentary time and light activity in the current trial (sedentary change, −8.1 %; light activity change, 7.9 %) were slightly larger than those seen in a recent trial by Bond et al [33] that used similar technology to interrupt sedentary time (sedentary change, -3.3 to −5.9 %; light activity change, 2.7 to 4.7 %).…”

Persuasive Technology in Mobile Applications Promoting Physical Activity: a Systematic Review

“…Figure 2 trial or outcome studies, five articles focused on software design and evaluation and the remaining articles are on focus groups and interview studies on stakeholders' opinions on smart phone apps for physical activity (see Table 1). [25] × × [26] × [27] × × × × × × × × × [28] × × × × × × × × [29] × × × × [30] × × × [31] × [32] × × × × × × × × × × × × [33] × × [34] × × × × × × × [35] × × × × [36] × × × × × × [37] × [38] × × × [39] × × × × × [40] × [41] × [42] × × × × [43] × × [44] Illustrations in figure 2 and table 2 show features that are highly present in articles on physical activity intervention studies, those features that were occasionally mentioned, or those that were not cited often in these articles. Visualisation of persuasive features is presented to provide more insights about the highlights, 9 gaps and blank spots [45] in current mobile application persuasive design features on physical activity.…”

“…Self-monitoring was implemented in the form of manual logging [27] or automatic tracking of physical activity [30], either in terms of step count [29], distance travelled [30], active time [31] or sedentary time [25], or other self-evaluation criteria. A qualitative study of user's attitudes towards mobile application promoting physical activity indicated that selfmonitoring is considered to be an important tool in behaviour modification [28].…”

“…After successfully responding to a prompt by performing a physical activity, a user might receive a message praising their accomplishment [25]. Applications provided both positive and negative messages depending on the activity levels of the individual [29].…”

“…Users were rewarded with a visually appealing symbols displayed on the application dashboard each time the user completed a physical activity [25]. Reward systems were implemented that encouraged users to complete physical exercise task with a series of rewards that could be progressively unlocked as the user completed exercise goals [30], or reached behaviour change milestones [33].…”