title: Postponed development of disability in elderly runners: a 13-year longitudinal study.
abstract: BACKGROUND
  The magnitude and duration of the benefit of running and other aerobic exercise on disability and mortality in elderly persons are not well understood. We sought to quantify the benefits of aerobic exercise, including running, on disability and mortality in elderly persons and to examine whether morbidity can be compressed into later years of life by regular exercise.
  
  
  METHODS
  A 13-year prospective cohort study of 370 members of a runners' club for persons aged 50 and older and 249 control subjects initially aged 50 to 72 years (mean, 59 years), with annual ascertainment of the Health Assessment Questionnaire disability score, noting any deaths and their causes. Linear mixed models were used to compute postponement in disability, and survival analysis was conducted to determine the time to and causes of death.
  
  
  RESULTS
  Significantly (P<.001) lower disability levels in runners' club members vs controls and in ever runners vs never runners were sustained for at least 13 years. Reaching a Health Assessment Questionnaire disability level of 0.075 was postponed by 8.7 (95% confidence interval [CI], 5.5-13.7) years in runners' club members vs controls. Running club membership and participation in other aerobic exercise protected against mortality (rate ratio, 0.36 [95% CI, 0.20-0.65] and 0.88 [95% CI, 0.77-0.99], respectively), while male sex and smoking were detrimental (rate ratio, 2.4 [95% CI, 1.4-4.2] and 2.2 [95% CI, 1.1-4.6], respectively). Controls had a 3.3 times higher rate of death than runners' club members, with higher death rates in every disease category. Accelerated rates of disability and mortality were still not seen in the runners' club members; true compression of morbidity was not yet observable through an average age of 72 years.
  
  
  CONCLUSIONS
  Running and other aerobic exercise in elderly persons protect against disability and early mortality, and are associated with prolongation of a disability-free life.
authors.affiliation: Department of Medicine, Stanford University School of Medicine, Stanford, Calif, USA. bwewang@utmem.edu
authors.forename: Benjamin W E
authors.initials: BW
authors.lastname: Wang
authors.forename: Dena R
authors.initials: DR
authors.lastname: Ramey
authors.forename: Jared D
authors.initials: JD
authors.lastname: Schettler
authors.forename: Helen B
authors.initials: HB
authors.lastname: Hubert
authors.forename: James F
authors.initials: JF
authors.lastname: Fries
mesh_terms: D000367:Age Factors; D000368:Aged; D015331:Cohort Studies; D006233:Persons with Disabilities; D015444:Exercise; D005260:Female; D006304:Health Status; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012420:Running; D016019:Survival Analysis; D013997:Time Factors