title: Effect of wrist-worn activity monitor feedback on physical activity behavior: A randomized controlled trial in Finnish young men.
abstract: The purpose of this study is to evaluate whether the use of an activity monitor providing feedback has an effect on physical activity (PA) in young men. A population-based sample of 276 conscription-aged (mean = 17.9, SD = 0.7 years) men participated in a 3-month randomized controlled trial in Oulu in 2012. Participants were randomized to an intervention group (INT, N = 137) and a control group (CON, N = 139). INT received a wrist-worn monitor (Polar Active) showing daily activity, and CON received identical monitors without feedback. Main outcome was the change from baseline in objectively measured weekly time spent in moderate-to-vigorous PA (MVPA) and sedentary activity (SED), as assessed by generalized estimation equations (GEE). Other lifestyle factors were assessed by a questionnaire at baseline and at 3 months. Weekly physical activity data (≥ 4 days with ≥ 8 h each) were obtained from 72 (53%) and 90 (65%) men in the INT and CON, respectively. Based on GEE, time spent in MVPA increased (p = 0.012) and SED decreased (p = 0.032) in the INT compared with the CON. During the first 7 weeks, the INT spent on average 1 h less sedentary than the CON (t-test, p < 0.05). During the first week, the INT showed 12 minutes more MVPA compared to the CON (t-test, p = 0.034). Based on questionnaire data, the proportion of the most sedentary men decreased in the INT (Wilcoxon test, 28% vs. 10%, p = 0.029), with no change in the CON (20% vs. 19%, p = 0.546). To conclude, a wrist-worn activity monitor providing feedback had a short-term positive effect on PA and SED in young men.
  
  
  BACKGROUND
  This is a pilot study for a larger randomized controlled trial registered to the clinical trials register NCT01376986.
authors: Medical Imaging, Physics and Technology Research Group, PO Box 5000, 90014, University of Oulu, Finland; Infotech Oulu, PO Box 4500, 90014, University of Oulu, Finland; Oulu Deaconess Institute, Department of Sports and Exercise Medicine, Albertinkatu 18 A, 90100 Oulu, Finland.
authors: Anna-Maiju
authors: AM
authors: Jauho
authors: Medical Imaging, Physics and Technology Research Group, PO Box 5000, 90014, University of Oulu, Finland; Oulu Deaconess Institute, Department of Sports and Exercise Medicine, Albertinkatu 18 A, 90100 Oulu, Finland; Medical Research Center, Oulu University Hospital, University of Oulu, Oulu, Finland; Center for Life Course and Systems Epidemiology (CLCE), PO Box 5000, 90014, University of Oulu, Finland.
authors: Riitta
authors: R
authors: Pyky
authors: Medical Imaging, Physics and Technology Research Group, PO Box 5000, 90014, University of Oulu, Finland; Medical Research Center, Oulu University Hospital, University of Oulu, Oulu, Finland.
authors: Riikka
authors: R
authors: Ahola
authors: Medical Imaging, Physics and Technology Research Group, PO Box 5000, 90014, University of Oulu, Finland; Medical Research Center, Oulu University Hospital, University of Oulu, Oulu, Finland.
authors: Maarit
authors: M
authors: Kangas
authors: Polar Electro, Professorintie 5, 90440 Kempele, Finland.
authors: Paula
authors: P
authors: Virtanen
authors: Oulu Deaconess Institute, Department of Sports and Exercise Medicine, Albertinkatu 18 A, 90100 Oulu, Finland; Medical Research Center, Oulu University Hospital, University of Oulu, Oulu, Finland; Center for Life Course and Systems Epidemiology (CLCE), PO Box 5000, 90014, University of Oulu, Finland.
authors: Raija
authors: R
authors: Korpelainen
authors: Medical Imaging, Physics and Technology Research Group, PO Box 5000, 90014, University of Oulu, Finland; Infotech Oulu, PO Box 4500, 90014, University of Oulu, Finland; Medical Research Center, Oulu University Hospital, University of Oulu, Oulu, Finland.
authors: Timo
authors: T
authors: Jämsä
keywords: Accelerometer; Health; Physical activity; Sedentary; Self-monitoring