title: Changes in soleus H-reflex during walking in middle-aged, healthy subjects.
abstract: BACKGROUND
  To assess the effect of aging on stretch reflex modulation during walking, soleus H-reflexes obtained in 15 middle-aged (mean age 56.4±6.9 years) and 15 young (mean age 23.7±3.9 years) subjects were compared.
  
  
  METHODS
  The H-reflex amplitude, muscle activity (EMG) of the soleus and tibialis anterior muscles, and EMG/H-reflex gain were measured during 4-km/h treadmill walking.
  
  
  RESULTS
  The normalized H-reflex amplitude was lower in the swing phase for the middle-aged group, and there was no difference in muscle activity. EMG/H-reflex gain did not differ between groups.
  
  
  CONCLUSIONS
  H-reflex amplitude during walking was affected by aging, and changes during the swing phase could be seen in the middle-aged subjects. Subdividing the 2 age groups into groups of facilitated or suppressed swing-phase H-reflex revealed that the H-reflex amplitude modulation pattern in the group with facilitated swing-phase H-reflex may be influenced by aging.
authors.affiliation: Department of Neuroscience and Pharmacology, University of Copenhagen, Blegdamsvej 3B, 2200, Copenhagen N, Denmark.
authors.forename: Peter C
authors.initials: PC
authors.lastname: Raffalt
authors.forename: Tine
authors.initials: T
authors.lastname: Alkjær
authors.forename: Erik B
authors.initials: EB
authors.lastname: Simonsen
mesh_terms: D000328:Adult; D000375:Aging / Q000502:physiology*; D004576:Electromyography / Q000379:methods; D005260:Female; D006181:H-Reflex / Q000502:physiology*; D006304:Health Status; D006801:Humans; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000502:physiology; D016138:Walking / Q000502:physiology*; D055815:Young Adult
keywords: EMG; H-reflex amplitude; M-wave; aging; walking