title: Recognition of physical activities in overweight Hispanic youth using KNOWME Networks.
abstract: BACKGROUND
  KNOWME Networks is a wireless body area network with 2 triaxial accelerometers, a heart rate monitor, and mobile phone that acts as the data collection hub. One function of KNOWME Networks is to detect physical activity (PA) in overweight Hispanic youth. The purpose of this study was to evaluate the in-laboratory recognition accuracy of KNOWME.
  
  
  METHODS
  Twenty overweight Hispanic participants (10 males; age 14.6 ± 1.8 years), underwent 4 data collection sessions consisting of 9 activities/session: lying down, sitting, sitting fidgeting, standing, standing fidgeting, standing playing an active video game, slow walking, brisk walking, and running. Data were used to train activity recognition models. The accuracy of personalized and generalized models is reported.
  
  
  RESULTS
  Overall accuracy for personalized models was 84%. The most accurately detected activity was running (96%). The models had difficulty distinguishing between the static and fidgeting categories of sitting and standing. When static and fidgeting activity categories were collapsed, the overall accuracy improved to 94%. Personalized models demonstrated higher accuracy than generalized models.
  
  
  CONCLUSIONS
  KNOWME Networks can accurately detect a range of activities. KNOWME has the ability to collect and process data in real-time, building the foundation for tailored, real-time interventions to increase PA or decrease sedentary time.
authors.affiliation: Institute for Health Promotion and Disease Prevention Research, University of Southern California, Alhambra, CA, USA.
authors.forename: B Adar
authors.initials: BA
authors.lastname: Emken
authors.forename: Ming
authors.initials: M
authors.lastname: Li
authors.forename: Gautam
authors.initials: G
authors.lastname: Thatte
authors.forename: Sangwon
authors.initials: S
authors.lastname: Lee
authors.forename: Murali
authors.initials: M
authors.lastname: Annavaram
authors.forename: Urbashi
authors.initials: U
authors.lastname: Mitra
authors.forename: Shrikanth
authors.initials: S
authors.lastname: Narayanan
authors.forename: Donna
authors.initials: D
authors.lastname: Spruijt-Metz
mesh_terms: D000054:Acceleration; D056044:Actigraphy / Q000295:instrumentation*; D000293:Adolescent; D000294:Adolescent Behavior; D015992:Body Mass Index; D002648:Child; D005260:Female; D006630:Hispanic or Latino / Q000706:statistics & numerical data*; D006801:Humans; D015141:Los Angeles / Q000453:epidemiology; D008297:Male; D009043:Motor Activity / Q000502:physiology*; D050177:Overweight / Q000453:epidemiology / Q000517:prevention & control*; D011634:Public Health; D012420:Running / Q000502:physiology; D057185:Sedentary Behavior; D014481:United States / Q000453:epidemiology