Effect of lower extremity functional electrical stimulation pulsed isometric contractions on arm cycling peak oxygen uptake in spinal cord injured individuals
Berit Brurok, Tom Tørhaug, Trine Karlsen, Gunnar Leivseth, Jan Helgerud, Jan Hoff
St Olavs Hospital, Department of Physical Medicine and Rehabilitation, Spinal Cord Injury Unit , Olav Kyrresgt 17, 7006 Trondheim, Norway. E-mail: firstname.lastname@example.org
Objective: To compare peak oxygen uptake (VO2peak) between: (i) functional electrical stimulation lower extremity pulsed isometric muscle contractions combined with arm cycling (FES iso hybrid), (ii) functional electrical stimulation cycling combined with arm cycling (FES hybrid cycling), and (iii) arm cycling exercise (ACE) in individuals with spinal cord injury with level of injury above and below T6.
Design: Cross-over repeated measures design.
Methods/participants: Individuals with spinal cord injury (n = 15) with level of injury between C4 and T12, were divided into groups; above (spinal cord injury – high, n = 8) and below (spinal cord injury – low, n = 7) T6 level. On separate days, VO2peak was compared between: (i) ACE, (ii) FES iso hybrid, and (iii) FES hybrid cycling.
Results: In the SCI–high group, FES iso hybrid increased VO2peak (17.6 (standard deviation (SD) 5.0) to 23.6 (SD 3.6) ml/kg/min; p = 0.001) and ventilation (50.4 (SD 20.8) to 58.2 (SD 20.7) l/min; p = 0.034) more than ACE. Furthermore, FES hybrid cycling resulted in a 6.8 ml/kg/min higher VO2peak (p = 0.001) and an 11.0 litres/minute (p = 0.001) higher ventilation. ACE peak workload was 10.5 W (p = 0.001) higher during FES hybrid cycling compared with ACE. In the spinal cord injury – low group, no significant differences were found between the modalities.
Conclusion: VO2peak increased when ACE was combined with FES iso hybrid or FES hybrid cycling in persons with spinal cord injury above the T6 level. Portable FES may serve as a less resource-demanding alternative to stationary FES cycling, and may have important implications for exercise prescription for spinal cord injury.