Central and peripheral haemodynamics in individuals with paraplegia duringlight and heavy exercise

The purpose of this study was to analyse lower leg skin blood flow (laser D oppler flowmetry) in five individuals with high-level paraplegia (T5-T9), s ix participants with low-level paraplegia (T10-T12) and six able-bodied con trols during 3-minute light and heavy arm-cranking exercises (similar to 15 % and 80% peak power output, respectively). Throughout light exercise, cuta neous vasoconstriction was shown for the control group (-20%), but not the low-level (+62%) or the high-level paraplegic group (+33%), During heavy ex ercise, vasoconstriction was initially found for controls followed by an in crease in skin blood flow during the last 2 minutes, whereas the participan ts with paraplegia demonstrated skin blood flow increases. Skin blood flow responses were not related to lesion level. Metabolic parameters were not d ifferent among the three groups, but heart rates for participants with para plegia were higher during heavy exercise than in controls. These results su ggest impaired sympathetic vasoconstriction in individuals with paraplegia during exercise.