title: Effect of stretching on ankle and knee angles and gastrocnemius activity during the stance phase of gait.
abstract: BACKGROUND
  Stretching exercises are commonly prescribed for patients and healthy individuals with limited extensibility of the gastrocnemius muscle.
  
  
  OBJECTIVE
  To determine effects of gastrocnemius stretching on ankle dorsiflexion, knee extension, and gastrocnemius muscle activity during gait.
  
  
  METHODS
  Randomized-control trial.
  
  
  METHODS
  Biomechanical laboratory.
  
  
  METHODS
  Sixteen volunteers (9 men and 7 women, mean age = 27 y) with less than 5 degrees of passive ankle-dorsiflexion range of motion randomly assigned to an experimental or control group.
  
  
  METHODS
  The experimental group performed gastrocnemius stretching for 3 wk.
  
  
  METHODS
  Maximum ankle dorsiflexion, maximum knee extension, and EMG amplitude of the gastrocnemius muscles were measured between heel strike and heel-off before and after intervention.
  
  
  RESULTS
  No significant effect of group or time was found on maximum ankle dorsiflexion, maximum knee extension, or EMG activity of the medial or lateral gastrocnemius muscles between heel strike and heel-off. The experimental group had significantly greater passive ankle-dorsiflexion range of motion bilaterally at posttest than the control group.
  
  
  CONCLUSIONS
  Stretching did not alter joint angles or gastrocnemius muscle activity in the early to midstance phase of gait.
authors.affiliation: Dept of Rehabilitation Medicine, Emory University School of Medicine, Atlanta, GA, USA.
authors.forename: Marie A
authors.initials: MA
authors.lastname: Johanson
authors.forename: Brian J
authors.initials: BJ
authors.lastname: Cuda
authors.forename: Jonathan E
authors.initials: JE
authors.lastname: Koontz
authors.forename: Julia C
authors.initials: JC
authors.lastname: Stell
authors.forename: Thomas A
authors.initials: TA
authors.lastname: Abelew
mesh_terms: D000328:Adult; D000843:Ankle Joint / Q000502:physiology*; D053587:Arthrometry, Articular; D001696:Biomechanical Phenomena; D016001:Confidence Intervals; D004576:Electromyography; D005260:Female; D005684:Gait / Q000502:physiology*; D006801:Humans; D007719:Knee Joint / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D052580:Muscle Stretching Exercises; D018482:Muscle, Skeletal / Q000502:physiology*; D011187:Posture; D016059:Range of Motion, Articular; D055815:Young Adult