title: Functional adaptation of tendon and skeletal muscle to resistance training in three patients with genetically verified classic Ehlers Danlos Syndrome.
abstract: BACKGROUND
  tendon and skeletal muscle function adapts to physical training of resistive nature, but it is unknown to what extent persons with genetically altered connective tissue - who have a higher than normal tendon extensibility - will obtain any effect upon their tendon and muscle when undergoing muscle strength training. We investigated patients with classical Ehlers Danlos Syndrome (EDS) (collagen type V defect) who display articular hypermobility, skin extensibility and tissue fragility.
  
  
  METHODS
  subjects underwent strength training 3 times a week for 4 months and were tested before and after intervention in regards to muscle strength, tendon mechanical properties, and muscle function.
  
  
  RESULTS
  three subjects completed the scheduled 48 sessions and had no major adverse events. Mean isometric leg extension force and leg extensor power both increased by 8 and 11% respectively (358 to 397 N, and 117 to 123 W). The tendon stiffness was tested and an average increase in response to physical training, from 1795 to 2519 N/mm was found. On average, the training loads both in upper and lower body exercises increased by around 30% over the training period. When testing balance, the average sway-area of the participants decreased by 26% (0.144 to 0.108 m(2)). On the subscale of CIS20 the participants lowered their average subjective fatigue score from 33 to 25.
  
  
  CONCLUSIONS
  in this small pilot study, heavy resistance training was both feasible and effective in classic Ehlers Danlos patients, and the results indicated that both tendon and skeletal muscle properties can be improved also in this patient group when they are subjected to resistance training.
authors.affiliation: Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Bispebjerg Hospital and Centre for Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark.
authors.forename: Mathias Bech
authors.initials: MB
authors.lastname: Møller
authors.affiliation: Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Bispebjerg Hospital and Centre for Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark.
authors.forename: Michael
authors.initials: M
authors.lastname: Kjær
authors.affiliation: Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Bispebjerg Hospital and Centre for Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark.
authors.forename: René Brüggebusch
authors.initials: RB
authors.lastname: Svensson
authors.affiliation: Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Bispebjerg Hospital and Centre for Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark.
authors.forename: Jesper Lovind
authors.initials: JL
authors.lastname: Andersen
authors.affiliation: Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Bispebjerg Hospital and Centre for Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark.
authors.forename: Stig Peter
authors.initials: SP
authors.lastname: Magnusson
authors.affiliation: Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Bispebjerg Hospital and Centre for Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark.
authors.forename: Rie Harboe
authors.initials: RH
authors.lastname: Nielsen
keywords: CIS20; patellar tendon; resistance training; sway