title: Wearable Sensor/Device (Fitbit One) and SMS Text-Messaging Prompts to Increase Physical Activity in Overweight and Obese Adults: A Randomized Controlled Trial.
abstract: BACKGROUND
  Studies have shown self-monitoring can modify health behaviors, including physical activity (PA). This study tested the utility of a wearable sensor/device (Fitbit(®) One™; Fitbit Inc., San Francisco, CA) and short message service (SMS) text-messaging prompts to increase PA in overweight and obese adults.
  
  
  METHODS
  Sixty-seven adults wore a Fitbit One tracker for 6 weeks; half were randomized to also receive three daily SMS-based PA prompts. The Fitbit One consisted of a wearable tracker for instant feedback on performance and a Web site/mobile application (app) for detailed summaries. Outcome measures were objectively measured steps and minutes of PA by intensity using two accelerometers: Actigraph™ (Pensacola, FL) GT3X+ (primary measure) at baseline and Week 6 and Fitbit One (secondary measure) at baseline and Weeks 1, 2, 3, 4, 5, and 6.
  
  
  RESULTS
  Mixed-model repeated-measures analysis of primary measures indicated a significant within-group increase of +4.3 (standard error [SE]=2.0) min/week of moderate- to vigorous-intensity PA (MVPA) at 6-week follow-up (p=0.04) in the comparison group (Fitbit only), but no study group differences across PA levels. Secondary measures indicated the SMS text-messaging effect lasted for only 1 week: the intervention group increased by +1,266 steps (SE=491; p=0.01), +17.8 min/week MVPA (SE=8.5; p=0.04), and +38.3 min/week total PA (SE=15.9; p=0.02) compared with no changes in the comparison group, and these between-group differences were significant for steps (p=0.01), fairly/very active minutes (p<0.01), and total active minutes (p=0.02).
  
  
  CONCLUSIONS
  These data suggest that the Fitbit One achieved a small increase in MVPA at follow-up and that the SMS-based PA prompts were insufficient in increasing PA beyond 1 week. Future studies can test this intervention in those requiring less help and/or test strategies to increase participants' engagement levels.
authors.affiliation: 1 Moores Cancer Center, University of California , San Diego, La Jolla, California.|2 Graduate School of Public Health, San Diego State University , San Diego, California.|3 Cardiovascular Research Institute, University of California , San Francisco, California.
authors.forename: Julie B
authors.initials: JB
authors.lastname: Wang
authors.affiliation: 1 Moores Cancer Center, University of California , San Diego, La Jolla, California.
authors.forename: Lisa A
authors.initials: LA
authors.lastname: Cadmus-Bertram
authors.affiliation: 1 Moores Cancer Center, University of California , San Diego, La Jolla, California.
authors.forename: Loki
authors.initials: L
authors.lastname: Natarajan
authors.affiliation: 1 Moores Cancer Center, University of California , San Diego, La Jolla, California.
authors.forename: Martha M
authors.initials: MM
authors.lastname: White
authors.affiliation: 2 Graduate School of Public Health, San Diego State University , San Diego, California.
authors.forename: Hala
authors.initials: H
authors.lastname: Madanat
authors.affiliation: 4 Center for Wireless Population Health Systems, University of California , San Diego, La Jolla, California.
authors.forename: Jeanne F
authors.initials: JF
authors.lastname: Nichols
authors.affiliation: 2 Graduate School of Public Health, San Diego State University , San Diego, California.
authors.forename: Guadalupe X
authors.initials: GX
authors.lastname: Ayala
authors.affiliation: 1 Moores Cancer Center, University of California , San Diego, La Jolla, California.
authors.forename: John P
authors.initials: JP
authors.lastname: Pierce
mesh_terms: D061725:Accelerometry / Q000295:instrumentation / Q000379:methods; D000293:Adolescent; D000328:Adult; D000368:Aged; D015444:Exercise; D005081:Exercise Therapy / Q000295:instrumentation / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000295:instrumentation / Q000379:methods; D009765:Obesity / Q000503:physiopathology / Q000628:therapy; D060145:Text Messaging
keywords: behavioral health; e-health; mobile health; sensor technology; technology