title: Randomized controlled trial of the efficacy of aerobic exercise in reducing metabolic risk in healthy older people: The Hertfordshire Physical Activity Trial.
abstract: BACKGROUND
  While there are compelling observational data confirming that individuals who exercise are healthier, the efficacy of aerobic exercise interventions to reduce metabolic risk and improve insulin sensitivity in older people has not been fully elucidated. Furthermore, while low birth weight has been shown to predict adverse health outcomes later in life, its influence on the response to aerobic exercise is unknown. Our primary objective is to assess the efficacy of a fully supervised twelve week aerobic exercise intervention in reducing clustered metabolic risk in healthy older adults. A secondary objective is to determine the influence of low birth weight on the response to exercise in this group.
  
  
  METHODS
  We aim to recruit 100 participants born between 1931-1939, from the Hertfordshire Cohort Study and randomly assign them to no intervention or to 36 fully supervised one hour sessions on a cycle ergometer, over twelve weeks. Each participant will undergo detailed anthropometric and metabolic assessment pre- and post-intervention, including muscle biopsy, magnetic resonance imaging and spectroscopy, objective measurement of physical activity and sub-maximal fitness testing.
  
  
  CONCLUSIONS
  Given the extensive phenotypic characterization, this study will provide valuable insights into the mechanisms underlying the beneficial effects of aerobic exercise as well as the efficacy, feasibility and safety of such interventions in this age group.
  
  
  BACKGROUND
  Current Controlled Trials: ISRCTN60986572.
authors: MRC Epidemiology Unit, Institute of Metabolic Science, Cambridge, UK. francis.finucane@mrc-epid.cam.ac.uk
authors: Francis M
authors: FM
authors: Finucane
authors: Jessica
authors: J
authors: Horton
authors: Lisa R
authors: LR
authors: Purslow
authors: David B
authors: DB
authors: Savage
authors: Soren
authors: S
authors: Brage
authors: Hervé
authors: H
authors: Besson
authors: Kenneth
authors: K
authors: Horton
authors: Ema De Lucia
authors: Ede L
authors: Rolfe
authors: Alison
authors: A
authors: Sleigh
authors: Stephen J
authors: SJ
authors: Sharp
authors: Helen J
authors: HJ
authors: Martin
authors: Avan Aihie
authors: AA
authors: Sayer
authors: Cyrus
authors: C
authors: Cooper
authors: Ulf
authors: U
authors: Ekelund
authors: Simon J
authors: SJ
authors: Griffin
authors: Nicholas J
authors: NJ
authors: Wareham