title: Online social networks that connect users to physical activity partners: a review and descriptive analysis.
abstract: BACKGROUND
  The US Centers for Disease Control and Prevention have identified a lack of encouragement, support, or companionship from family and friends as a major barrier to physical activity. To overcome this barrier, online social networks are now actively leveraging principles of companion social support in novel ways.
  
  
  OBJECTIVE
  The aim was to evaluate the functionality, features, and usability of existing online social networks which seek to increase physical activity and fitness among users by connecting them to physical activity partners, not just online, but also face-to-face.
  
  
  METHODS
  In September 2012, we used 3 major databases to identify the website addresses for relevant online social networks. We conducted a Google search using 8 unique keyword combinations: the common keyword "find" coupled with 1 of 4 prefix terms "health," "fitness," "workout," or "physical" coupled with 1 of 2 stem terms "activity partners" or "activity buddies." We also searched 2 prominent technology start-up news sites, TechCrunch and Y Combinator, using 2 unique keyword combinations: the common keyword "find" coupled with 1 of 2 stem terms "activity partners" and "activity buddies." Sites were defined as online social health activity networks if they had the ability to (1) actively find physical activity partners or activities for the user, (2) offer dynamic, real-time tracking or sharing of social activities, and (3) provide virtual profiles to users. We excluded from our analysis sites that were not Web-based, publicly available, in English, or free.
  
  
  RESULTS
  Of the 360 initial search results, we identified 13 websites that met our complete criteria of an online social health activity network. Features such as physical activity creation (13/13, 100%) and private messaging (12/13, 92%) appeared almost universally among these websites. However, integration with Web 2.0 technologies such as Facebook and Twitter (9/13, 69%) and the option of direct event joining (8/13, 62%) were not as universally present. Largely absent were more sophisticated features that would enable greater usability, such as interactive engagement prompts (3/13, 23%) and system-created best fit activities (3/13, 23%).
  
  
  CONCLUSIONS
  Several major online social networks that connect users to physical activity partners currently exist and use standardized features to achieve their goals. Future research is needed to better understand how users utilize these features and how helpful they truly are.
authors.affiliation: School of Medicine, Johns Hopkins University, Baltimore, MD, United States.
authors.forename: Atul
authors.initials: A
authors.lastname: Nakhasi
authors.forename: Album Xiaotian
authors.initials: AX
authors.lastname: Shen
authors.forename: Ralph Joseph
authors.initials: RJ
authors.lastname: Passarella
authors.forename: Lawrence J
authors.initials: LJ
authors.lastname: Appel
authors.forename: Cheryl Am
authors.initials: CA
authors.lastname: Anderson
mesh_terms: D016208:Databases, Factual; D006801:Humans; D020407:Internet; D009043:Motor Activity; D061108:Social Media; D060756:Social Networking; D012944:Social Support; D014481:United States
keywords: Internet; Web; behavior; behavior control; behavioral research; exercise; health; health behavior; information services; intervention studies; online systems; physical fitness; social media; social medicine; social networking; social support; telemedicine