title: Objectively-measured outdoor time and physical and psychological function among older adults.
abstract: OBJECTIVE
  Objective measurements of outdoor time are essential to establishing evidence about the health benefits of going outdoors among older adults. To better understanding the health benefits of going outdoors, clarification of potential mediators to connect going outdoors with health benefits is necessary. The present study aimed to investigate associations of objectively-measured outdoor time with older adults' physical and psychological function, and examine the mediating role of physical activity on these associations.
  
  
  METHODS
  Baseline data from a randomized control trial of physical activity among older adults with global cognitive impairment was used. Data from 192 participants were analyzed. Measures included steps-per-day, objectively-measured outdoor time per day using global positioning systems, physical function (cardiorespiratory fitness, lower-extremity strength), psychological function (depression, well-being) and basic factors.
  
  
  RESULTS
  Path analysis showed that outdoor time was significantly associated with steps-per-day (path coefficient = 0.23) and depression (path coefficient = -0.16). Outdoor time was not directly associated with cardiorespiratory fitness, lower-extremity strength and well-being. However, steps-per-day was associated with cardiorespiratory fitness (path coefficient = 0.18), lower-extremity strength (path coefficient = -0.22) and well-being (path coefficient = 0.14).
  
  
  CONCLUSIONS
  We found that objectively-measured outdoor time was indirectly associated with physical function, and both directly and indirectly with psychological function through physical activity among older adults. This finding indicates that going outdoors influences older adults' health outcomes, and is mainly mediated by physical activity. Geriatr Gerontol Int 2017; 17: 1455-1462.
authors.affiliation: Graduate School of Human Development and Environment, Kobe University, Kobe, Hyogo, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Harada
authors.affiliation: Department of Preventive Gerontology, National Center for Geriatrics and Gerontology, Obu, Aichi, Japan.
authors.forename: Sangyoon
authors.initials: S
authors.lastname: Lee
authors.affiliation: Department of Preventive Gerontology, National Center for Geriatrics and Gerontology, Obu, Aichi, Japan.
authors.forename: Sungchul
authors.initials: S
authors.lastname: Lee
authors.affiliation: Department of Preventive Gerontology, National Center for Geriatrics and Gerontology, Obu, Aichi, Japan.
authors.forename: Seongryu
authors.initials: S
authors.lastname: Bae
authors.affiliation: School of Health and Sport Sciences, Chukyo University, Toyota, Aichi, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Harada
authors.affiliation: Institute for Gerontology, J. F. Oberlin University, Machida, Tokyo, Japan.
authors.forename: Takao
authors.initials: T
authors.lastname: Suzuki
authors.affiliation: Department of Preventive Gerontology, National Center for Geriatrics and Gerontology, Obu, Aichi, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Shimada
mesh_terms: D000203:Activities of Daily Living; D000368:Aged; D000369:Aged, 80 and over; D003071:Cognition / Q000502:physiology*; D060825:Cognitive Dysfunction / Q000503:physiopathology / Q000523:psychology / Q000534:rehabilitation*; D015444:Exercise / Q000502:physiology*; D005081:Exercise Therapy / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D009043:Motor Activity / Q000502:physiology*
keywords: aged; geographic information systems; homebound persons; mental health; motor activity