Rapid Vascular Adaptations to Training and Detraining in Persons With Spinal Cord Injury
Abstract
Thijssen DH, Ellenkamp R, Smits P, Hopman MT. Rapid vascular adaptations to training and detraining in persons with spinal cord injury.
Objective
To assess the time course of arterial adaptations during 6 weeks of functional electric stimulation (FES) training and 6 weeks of detraining in subjects with spinal cord injury (SCI).
Design
Intervention study (before-after trial).
Setting
University medical center.
Participants
Volunteer sample of 9 subjects with SCI.
Interventions
Six weeks of twice weekly FES cycling and 6 weeks of detraining.
Main Outcome Measures
Vascular characteristics were measured by plethysmography (baseline and peak blood flow of the thigh) and echo Doppler (diameter of the femoral artery and flow-mediated dilation [FMD]).
Results
After 2 weeks of FES training, arterial characteristics changed significantly; there was an increase in baseline and peak blood flow, an increase in femoral artery diameter, and a decrease in FMD of the femoral artery. Detraining reversed baseline and peak thigh blood flow, vascular resistance, and femoral diameter toward pretraining values within 1 week. However, detraining did not restore the FMD of the femoral artery, even after 6 weeks.
Conclusions
Two weeks of hybrid FES training (4 exercise bouts) is sufficient to improve peak leg blood flow and arterial diameter, and to normalize FMD. In addition, detraining results in rapidly reversed vascular characteristics within 1 week.
aDepartment of Physiology, Institute for Fundamental and Clinical Human Movement Sciences, the Netherlands
bDepartment of Pharmacology, Radboud University Nijmegen Medical Centre, the Netherlands
Correspondence to Maria T. Hopman, MD, PhD, Dept of Physiology, RUNMC, PO Box 9101, 6500 HB Nijmegen, The Netherlands. Reprints are not available from the author.
Supported by the Johan van Drongelen Foundation.
No commercial party having a direct financial interest in the results of the research supporting this article has or will confer a benefit upon the author(s) or upon any organization with which the author(s) is/are associated.
ABSTRACT