title: Muscle activity of leg muscles during unipedal stance on therapy devices with different stability properties.
abstract: OBJECTIVE
  To test the hypotheses that less stable therapy devices require greater muscle activity and that lower leg muscles will have greater increases in muscle activity with less stable therapy devices than upper leg muscles.
  
  
  METHODS
  Cross-sectional laboratory study.
  
  
  METHODS
  Laboratory setting.
  
  
  METHODS
  Twenty-five healthy subjects.
  
  
  METHODS
  Electromyographic activity of four lower (gastrocnemius medialis, soleus, tibialis anterior, peroneus longus) and four upper leg muscles (vastus medialis and lateralis, biceps femoris, semitendinosus) during unipedal quiet barefoot stance on the dominant leg on a flat rigid surface and on five therapy devices with varying stability properties.
  
  
  RESULTS
  Muscle activity during unipedal stance differed significantly between therapy devices (P < 0.001). The order from lowest to highest relative muscle activity matched the order from most to least stable therapy device. There was no significant interaction between muscle location (lower versus upper leg) and therapy device (P = 0.985). Magnitudes of additional relative muscle activity for the respective therapy devices differed substantially among lower extremity muscles.
  
  
  CONCLUSIONS
  The therapy devices offer a progressive increase in training intensity, and thus may be useful for incremental training programs in physiotherapeutic practice and sports training programs.
authors.affiliation: Kantonsspital Baselland, Bruderholz, Switzerland.
authors.forename: Thomas
authors.initials: T
authors.lastname: Wolburg
authors.affiliation: Institute for Sport and Sport Sciences, Albert-Ludwigs University Freiburg, Germany; Department of Sports Medicine, University Hospital Tübingen, Germany. Electronic address: walter.rapp@sport.uni-freiburg.de.
authors.forename: Walter
authors.initials: W
authors.lastname: Rapp
authors.affiliation: Department of Sports Medicine, University Hospital Tübingen, Germany.
authors.forename: Jochen
authors.initials: J
authors.lastname: Rieger
authors.affiliation: Medical Park Bad Wiessee St. Hubertus, Bad Wiessee, Germany; Faculty for Sport and Health Sciences, Technische Universität München, Munich, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Horstmann
mesh_terms: D000328:Adult; D003430:Cross-Sectional Studies; D004576:Electromyography; D004867:Equipment Design; D005260:Female; D006801:Humans; D007866:Leg / Q000502:physiology*; D007869:Leg Injuries / Q000534:rehabilitation*; D008297:Male; D018482:Muscle, Skeletal / Q000502:physiology*; D026741:Physical Therapy Modalities / Q000295:instrumentation*; D004856:Postural Balance / Q000502:physiology*; D016138:Walking / Q000502:physiology*
keywords: Balance training; Lower extremity; Muscle activity; Stability properties