title: Electromyographic patterns of lower limb muscles during apprehensive gait in younger and older female adults.
abstract: OBJECTIVE
  Investigate the influence of apprehensive gait on activation and cocontraction of lower limb muscles of younger and older female adults.
  
  
  METHODS
  Data of 17 younger (21.47±2.06yr) and 18 older women (65.33±3.14yr) were considered for this study. Participants walked on the treadmill at two different conditions: normal gait and apprehensive gait. The surface electromyographic signals (EMG) were recorded during both conditions on: rectus femoris (RF), vastus lateralis (VL), vastus medialis (VM), biceps femoris (BF), tibialis anterior (TA), gastrocnemius lateralis (GL), and soleus (SO).
  
  
  RESULTS
  Apprehensive gait promoted greater activation of thigh muscles than normal gait (F=5.34 and p=0.007, for significant main effect of condition; RF, p=0.002; VM, p<0.001; VL, p=0.003; and BF, p=0.001). Older adults had greater cocontraction of knee and ankle stabilizer muscles than younger women (F=4.05 and p=0.019, for significant main effect of groups; VM/BF, p=0.010; TA/GL, p=0.007; and TA/SO, p=0.002).
  
  
  CONCLUSIONS
  Apprehensive gait promoted greater activation of thigh muscles and older adults had greater cocontraction of knee and ankle stabilizer muscles. Thus, apprehensive gait may leads to increased percentage of neuromuscular capacity, which is associated with greater cocontraction and contribute to the onset of fatigue and increased risk of falling in older people.
authors.affiliation: Department of Physical Education, São Paulo State University, Rio Claro, Brazil. camillazhallal@yahoo.com.br
authors.forename: Camilla Zamfolini
authors.initials: CZ
authors.lastname: Hallal
authors.forename: Nise Ribeiro
authors.initials: NR
authors.lastname: Marques
authors.forename: Deborah Hebling
authors.initials: DH
authors.lastname: Spinoso
authors.forename: Edgar Ramos
authors.initials: ER
authors.lastname: Vieira
authors.forename: Mauro
authors.initials: M
authors.lastname: Gonçalves
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging / Q000502:physiology*; D000843:Ankle Joint / Q000502:physiology; D059031:Anticipation, Psychological / Q000502:physiology*; D004576:Electromyography / Q000379:methods; D005239:Fear / Q000502:physiology*; D005260:Female; D005684:Gait / Q000502:physiology*; D006801:Humans; D007719:Knee Joint / Q000502:physiology; D007866:Leg / Q000502:physiology*; D008875:Middle Aged; D009119:Muscle Contraction / Q000502:physiology*; D018482:Muscle, Skeletal / Q000502:physiology*; D016138:Walking / Q000502:physiology
keywords: Biomechanics; Cocontraction; Dual task gait; Elderly; Falls