title: Physical activity across adulthood and physical performance in midlife: findings from a British birth cohort.
abstract: BACKGROUND
  Evidence, mainly from cross-sectional studies, suggests that physical activity is a potentially important modifiable factor associated with physical performance and strength in older age. It is unclear whether the benefits of physical activity accumulate across life or whether there are sensitive periods when physical activity is more influential.
  
  
  OBJECTIVE
  To examine the associations of leisure-time physical activity across adulthood with physical performance and strength in midlife, and to test whether there are cumulative benefits of physical activity.
  
  
  METHODS
  Using data on approximately 2400 men and women from the UK Medical Research Council National Survey of Health and Development, followed up since birth in March 1946, the associations of physical activity levels during leisure time self-reported prospectively at ages 36, 43, and 53 years with grip strength, standing balance, and chair rise times, assessed by nurses at age 53 years (in 1999), were examined in 2010.
  
  
  RESULTS
  There were independent positive effects of physical activity at all three ages on chair rise performance, and at ages 43 and 53 years on standing balance performance, even after adjusting for covariates. These results were supported by evidence of cumulative effects found when using structured life course models. Physical activity and grip strength were not associated in women and, in men, only physical activity at age 53 years was associated with grip strength.
  
  
  CONCLUSIONS
  There are cumulative benefits of physical activity across adulthood on physical performance in midlife. Increased activity should be promoted early in adulthood to ensure the maintenance of physical performance in later life.
authors.affiliation: MRC Unit for Lifelong Health and Ageing, Division of Population Health, University College London, United Kingdom. r.cooper@nshd.mrc.ac.uk
authors.forename: Rachel
authors.initials: R
authors.lastname: Cooper
authors.forename: Gita D
authors.initials: GD
authors.lastname: Mishra
authors.forename: Diana
authors.initials: D
authors.lastname: Kuh
mesh_terms: D000328:Adult; D000367:Age Factors; D003430:Cross-Sectional Studies; D015444:Exercise; D005260:Female; D018737:Hand Strength / Q000502:physiology*; D006801:Humans; D007899:Leisure Activities; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009043:Motor Activity; D010809:Physical Fitness; D004856:Postural Balance / Q000502:physiology*; D011446:Prospective Studies; D057566:Self Report; D012737:Sex Factors; D013997:Time Factors; D006113:United Kingdom; D044465:White People