title: A Review of the Potential Local Mechanisms by Which Exercise Improves Functional Outcomes in Intermittent Claudication.
abstract: BACKGROUND
  Intermittent claudication (IC) is a common condition which is associated with significant quality of life limitation. National Institute for Health and Care Excellence guidelines recommend a group-based supervised exercise program as the primary treatment option for claudication, based on clinical and cost effectiveness. This review aims to assess the mechanisms by which exercise improves outcomes in patients with IC.
  
  
  METHODS
  MEDLINE, EMBASE, and PubMed were searched using the search strategy "claudication" [AND] "exercise" [AND] "mechanisms." Searches were limited from 1947 to October 2014. Only full-text articles published in the English language in adults (over 18 years of age) were eligible for the review. Any trial involving a nonsupervised exercise program was excluded. Abstracts identified by the database search were interrogated for relevance and citations from the shortlisted papers were hand searched for relevant references.
  
  
  RESULTS
  The search yielded a total of 112 studies, of which 42 were duplicates. Forty-seven of the remaining 70 were deemed appropriate for inclusion in the review. Exercise is the first-line treatment for IC. Supervised exercise programs improve walking distances, endothelial and mitochondrial function, muscle strength, and endurance. Furthermore, it leads to a generalized improvement in cardiovascular fitness and overall quality of life.
  
  
  CONCLUSIONS
  The mechanism by which exercise improves outcome in claudicants is complicated and multifactorial. Further research is required in this area to fully elucidate the precise and predominant mechanisms and to assess whether targeted exercise program modification maximizes mechanism efficacy and patient outcome.
authors.affiliation: Vascular Department, Hull Royal Infirmary, University of Hull, Hull, UK. Electronic address: Amy.Harwood@hey.nhs.uk.
authors.forename: Amy-Elizabeth
authors.initials: AE
authors.lastname: Harwood
authors.affiliation: Vascular Department, Hull Royal Infirmary, University of Hull, Hull, UK.
authors.forename: Thomas
authors.initials: T
authors.lastname: Cayton
authors.affiliation: Vascular Department, Hull Royal Infirmary, University of Hull, Hull, UK.
authors.forename: Romesh
authors.initials: R
authors.lastname: Sarvanandan
authors.affiliation: Vascular Department, Hull Royal Infirmary, University of Hull, Hull, UK.
authors.forename: Risha
authors.initials: R
authors.lastname: Lane
authors.affiliation: Vascular Department, Hull Royal Infirmary, University of Hull, Hull, UK.
authors.forename: Ian
authors.initials: I
authors.lastname: Chetter
mesh_terms: D000328:Adult; D015444:Exercise / Q000502:physiology*; D005081:Exercise Therapy; D006801:Humans; D007383:Intermittent Claudication / Q000503:physiopathology* / Q000628:therapy*