Acute peripheral blood flow response induced by passive leg cycle exercise in people with spinal cord injury

Objective: To determine the acute femoral artery hemodynamic response in paraplegic subjects during a passive leg cycle exercise. Design: Case series. Setting: Department of physical medicine and rehabilitation in a university in France. Participants: A volunteer sample of 15 people with traumatic spinal cord injury. Intervention: Subjects performed a 10-minute session of passive leg cycle exercise in the sitting position. Main Outcome Measures: We measured heart rate, maximal (Vmax), and minimal femoral artery blood flow velocity at rest and immediately after the passive leg cycle exercise, using quantitative duplex Doppler ultrasound. We calculated mean blood flow velocity (Vmean) and velocity index, representing the peripheral resistance, for each condition. Results: Vmax and Vmean increased (from .80 +/- .18 m/s to.96 +/-.24m/s, P <.01; and from .058 +/-.02 m/s to .076 +/-.03m/s, P<.01; respectively) after 10 minutes of passive leg cycle exercise. Heart rate did not change. The velocity index decreased from 1.23 +/- 0.15 to 1.16 +/- 0.21 (P=.038). Conclusions: The results of this study suggest that acute passive leg cycle exercise increases vascular blood flow velocity in paralyzed legs of people with paraplegia. This exercise could have clinical implications for immobilized persons.