title: Effects of short term water immersion on peripheral reflex excitability in hemiplegic and healthy individuals: A preliminary study.
abstract: BACKGROUND
  Reflex excitability is increased in hemiplegic patients compared to healthy controls. One challenge of stroke rehabilitation is to decrease the effects of hyperreflexia, which may be possible with water immersion. Methods/Aims: The present study examined the effects of acute water immersion on electrically-evoked Hmax:Mmax ratios (a measure of reflex excitability) in 7 hyperreflexive hemiplegic patients and 7 age-matched healthy people. Hmax:Mmax ratios were measured from soleus on dry land (L1), immediately after (W1) and 5 minutes after immersion (W5), and again after five minutes on land (L5).
  
  
  RESULTS
  Water immersion led to an acute increase in Hmax:Mmax ratio in both groups. However, after returning to dry land, there was a non-significant decrease in the Hmax:Mmax ratio of 8% in the hemiplegic group and 10% in healthy controls compared to pre-immersion values.
  
  
  CONCLUSIONS
  A short period of water immersion can decrease peripheral reflex excitability after returning to dry land in both healthy controls and post-stroke patients, although longer immersion periods may be required for sustainable effects. Water immersion may offer promise as a low-risk, non-invasive and non-pharmaceutical method of decreasing hyperreflexivity, and could thus support aquatic rehabilitation following stroke.
authors.affiliation: University of Jyvaskyla, Neuromuscular Research Center, Department of Biology of Physical Activity, Finland.
authors.forename: N J
authors.initials: NJ
authors.lastname: Cronin
authors.forename: A M
authors.initials: AM
authors.lastname: Valtonen
authors.forename: B
authors.initials: B
authors.lastname: Waller
authors.forename: T
authors.initials: T
authors.lastname: Pöyhönen
authors.forename: J
authors.initials: J
authors.lastname: Avela
mesh_terms: D002543:Cerebral Hemorrhage / Q000150:complications / Q000534:rehabilitation; D004576:Electromyography; D005260:Female; D006181:H-Reflex / Q000502:physiology*; D006429:Hemiplegia / Q000150:complications* / Q000534:rehabilitation*; D006801:Humans; D007101:Immersion; D008297:Male; D008875:Middle Aged; D012021:Reflex, Abnormal; D020521:Stroke / Q000150:complications; D000071939:Stroke Rehabilitation / Q000379:methods; D014867:Water
chemical_list: D014867:Water