title: Physical activity interventions targeting older adults. A critical review and recommendations.
abstract: BACKGROUND
  Although many of the chronic conditions plaguing older populations are preventable through appropriate lifestyle interventions such as regular physical activity, persons in this age group represent the most sedentary segment of the adult population. The purpose of the current paper was to provide a critical selected review of the scientific literature focusing on interventions to promote physical activity among older adults.
  
  
  METHODS
  Comprehensive computerized searches of the recent English language literature aimed at physical activity intervention in adults aged 50 years and older, supplemented with visual scans of several journal on aging, were undertaken. Articles were considered to be relevant for the current review if they were community-based, employed a randomized design or a quasi-experimental design with an appropriate comparison group, and included information on intervention participation rates, pre- and post-intervention physical activity levels, and/or pre/post changes in relevant physical performance measures.
  
  
  RESULTS
  Twenty-nine studies were identified that fit the stated criteria. Among the strengths of the studies reviewed were reasonable physical activity participation rates and relatively long study durations. Among the weaknesses of the literature reviewed were the relative lack of specific behavioral or program-based strategies aimed at promoting physical activity participation, as well as the dearth of studies aimed at replication, generalizability of interventions to important subgroups, implementation, and cost-effectiveness evaluation.
  
  
  CONCLUSIONS
  Recommendations for future scientific endeavors targeting older adults are discussed.
authors.affiliation: Department of Health Research and Policy, Stanford University School of Medicine, Palo Alto, California 94304-1583, USA.
authors.forename: A C
authors.initials: AC
authors.lastname: King
authors.forename: W J
authors.initials: WJ
authors.lastname: Rejeski
authors.forename: D M
authors.initials: DM
authors.lastname: Buchner
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D015444:Exercise; D005260:Female; D005500:Follow-Up Studies; D006293:Health Promotion; D006801:Humans; D007899:Leisure Activities; D008019:Life Style; D008875:Middle Aged; D005082:Physical Exertion; D010809:Physical Fitness; D011634:Public Health; D011897:Random Allocation; D016032:Randomized Controlled Trials as Topic; D012106:Research; D013997:Time Factors; D016138:Walking