title: Effect of structured physical activity on prevention of major mobility disability in older adults: the LIFE study randomized clinical trial.
abstract: OBJECTIVE
  In older adults reduced mobility is common and is an independent risk factor for morbidity, hospitalization, disability, and mortality. Limited evidence suggests that physical activity may help prevent mobility disability; however, there are no definitive clinical trials examining whether physical activity prevents or delays mobility disability.
  
  
  OBJECTIVE
  To test the hypothesis that a long-term structured physical activity program is more effective than a health education program (also referred to as a successful aging program) in reducing the risk of major mobility disability.
  
  
  METHODS
  The Lifestyle Interventions and Independence for Elders (LIFE) study was a multicenter, randomized trial that enrolled participants between February 2010 and December 2011, who participated for an average of 2.6 years. Follow-up ended in December 2013. Outcome assessors were blinded to the intervention assignment. Participants were recruited from urban, suburban, and rural communities at 8 centers throughout the United States. We randomized a volunteer sample of 1635 sedentary men and women aged 70 to 89 years who had physical limitations, defined as a score on the Short Physical Performance Battery of 9 or below, but were able to walk 400 m.
  
  
  METHODS
  Participants were randomized to a structured, moderate-intensity physical activity program (n = 818) conducted in a center (twice/wk) and at home (3-4 times/wk) that included aerobic, resistance, and flexibility training activities or to a health education program (n = 817) consisting of workshops on topics relevant to older adults and upper extremity stretching exercises.
  
  
  METHODS
  The primary outcome was major mobility disability objectively defined by loss of ability to walk 400 m.
  
  
  RESULTS
  Incident major mobility disability occurred in 30.1% (246 participants) of the physical activity group and 35.5% (290 participants) of the health education group (hazard ratio [HR], 0.82 [95% CI, 0.69-0.98], P = .03).Persistent mobility disability was experienced by 120 participants (14.7%) in the physical activity group and 162 participants (19.8%) in the health education group (HR, 0.72 [95% CI, 0.57-0.91]; P = .006). Serious adverse events were reported by 404 participants (49.4%) in the physical activity group and 373 participants (45.7%) in the health education group (risk ratio, 1.08 [95% CI, 0.98-1.20]).
  
  
  CONCLUSIONS
  A structured, moderate-intensity physical activity program compared with a health education program reduced major mobility disability over 2.6 years among older adults at risk for disability. These findings suggest mobility benefit from such a program in vulnerable older adults.
  
  
  BACKGROUND
  clinicaltrials.gov Identifier: NCT01072500.
authors.affiliation: Department of Aging and Geriatric Research,University of Florida, Gainesville.
authors.forename: Marco
authors.initials: M
authors.lastname: Pahor
authors.affiliation: Department of Aging and Geriatric Research,University of Florida, Gainesville2Department of Epidemiology and Public Health, University of Maryland School of Medicine, Baltimore.
authors.forename: Jack M
authors.initials: JM
authors.lastname: Guralnik
authors.affiliation: Department of Internal Medicine, Wake Forest University and School of Medicine, Winston-Salem, North Carolina.
authors.forename: Walter T
authors.initials: WT
authors.lastname: Ambrosius
authors.affiliation: Department of Exercise Science, Arnold School of Public Health, University of South Carolina, Columbia.
authors.forename: Steven
authors.initials: S
authors.lastname: Blair
authors.affiliation: Division of Cardiac Sciences, National Heart, Lung, and Blood Institute, Bethesda, Maryland.
authors.forename: Denise E
authors.initials: DE
authors.lastname: Bonds
authors.affiliation: Department of Preventative Medicine, Pennington Biomedical Research Center, Louisiana.
authors.forename: Timothy S
authors.initials: TS
authors.lastname: Church
authors.affiliation: Department of Internal Medicine, Wake Forest University and School of Medicine, Winston-Salem, North Carolina.
authors.forename: Mark A
authors.initials: MA
authors.lastname: Espeland
authors.affiliation: Jean Mayer United States Department of Agriculture Human Nutrition Research Center on Aging, Tufts University, Boston, Massachusetts.
authors.forename: Roger A
authors.initials: RA
authors.lastname: Fielding
authors.affiliation: Department of Internal Medicine, Yale School of Medicine, New Haven, Connecticut.
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Gill
authors.affiliation: Veterans Affairs San Diego Healthcare System, San Diego, California10Department of Family and Preventive Medicine, University of California, San Diego, San Diego.
authors.forename: Erik J
authors.initials: EJ
authors.lastname: Groessl
authors.affiliation: Department of Health Research and Policy and Department of Medicine, Stanford University, School of Medicine, Stanford, California.
authors.forename: Abby C
authors.initials: AC
authors.lastname: King
authors.affiliation: Department of Internal Medicine, Wake Forest University and School of Medicine, Winston-Salem, North Carolina.
authors.forename: Stephen B
authors.initials: SB
authors.lastname: Kritchevsky
authors.affiliation: Department of Aging and Geriatric Research,University of Florida, Gainesville.
authors.forename: Todd M
authors.initials: TM
authors.lastname: Manini
authors.affiliation: Department of Medicine and Preventive Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois.
authors.forename: Mary M
authors.initials: MM
authors.lastname: McDermott
authors.affiliation: Department of Internal Medicine, Wake Forest University and School of Medicine, Winston-Salem, North Carolina.
authors.forename: Michael E
authors.initials: ME
authors.lastname: Miller
authors.affiliation: Department of Epidemiology, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, Pennsylvania.
authors.forename: Anne B
authors.initials: AB
authors.lastname: Newman
authors.affiliation: Department of Internal Medicine, Wake Forest University and School of Medicine, Winston-Salem, North Carolina.
authors.forename: W Jack
authors.initials: WJ
authors.lastname: Rejeski
authors.affiliation: Department of Internal Medicine, Wake Forest University and School of Medicine, Winston-Salem, North Carolina.
authors.forename: Kaycee M
authors.initials: KM
authors.lastname: Sink
authors.affiliation: Department of Internal Medicine, Wake Forest University and School of Medicine, Winston-Salem, North Carolina.
authors.forename: Jeff D
authors.initials: JD
authors.lastname: Williamson
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D006233:Persons with Disabilities; D015444:Exercise; D005081:Exercise Therapy; D005260:Female; D006266:Health Education; D006801:Humans; D008019:Life Style; D008297:Male; D019957:Motor Skills Disorders / Q000517:prevention & control*; D012306:Risk; D057185:Sedentary Behavior; D016037:Single-Blind Method; D016138:Walking