title: Age-related differences in Tai Chi gait kinematics and leg muscle electromyography: a pilot study.
abstract: OBJECTIVE
  To compare the biomechanic features of Tai Chi gait by elders with those by young adults, and with those of normative gait.
  
  
  METHODS
  Cross-sectional study.
  
  
  METHODS
  Laboratory-based testing.
  
  
  METHODS
  Young (n=6; 3 women) and old (n=6; 5 women) Tai Chi practitioners.
  
  
  METHODS
  All subjects had practiced Tai Chi for at least 4 months.
  
  
  METHODS
  Spatial, temporal, and leg muscle electromyography during Tai Chi gait and normative gait.
  
  
  RESULTS
  The primary age-related differences in Tai Chi gait were during single stance, with elders having significantly shorter single-stance time (-50%), less lateral displacement (-30%), knee flexion (-42%), hip flexion (-39%), activation time in the tibialis anterior (-13%), soleus (-39%), and tensor fascia lata (TFL) (-21%), activation magnitude in the tibialis anterior (-39%), and coactivation time of the tibialis anterior and soleus (-47%). Compared with normative gait, elders during Tai Chi gait had significantly larger knee (139%) and hip (66%) flexions, longer duration (90%-170%) and higher magnitude (200%-400%) of the tibialis anterior, rectus femoris, and TFL muscle activities, and longer duration of coactivation of most leg muscle pairs (130%-380%).
  
  
  CONCLUSIONS
  The elders practice Tai Chi gait in higher posture than younger subjects. The Tai Chi gait poses significantly higher challenges to elder's balance and muscular system than does their normative gait.
authors.affiliation: Department of Rehabilitation and Movement Science, University of Vermont, Burlington, VT 05401, USA. ge.wu@uvm.edu
authors.forename: Ge
authors.initials: G
authors.lastname: Wu
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001696:Biomechanical Phenomena; D003430:Cross-Sectional Studies; D004576:Electromyography; D005260:Female; D005684:Gait / Q000502:physiology*; D006801:Humans; D007866:Leg / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000502:physiology*; D010865:Pilot Projects; D026302:Tai Ji / Q000379:methods*