1. Measurements of peak oxygen uptake (VO2peak) during passive leg cycling (PLC) combined with arm crank ergometry (ACE), leg vascular occlusion (100mmHg above systolic BP) combined with ACE, and FES isometric contractions combined with ACE in spinal cord injured (SCI). All the above mentioned parameters will be compared to Functional Electrical Stimulated (FES) lower extremity cycling combined with ACE (FEShybrid). The hypothesis is that VO2peak is significantly higher during FES hybrid cycling when compared to peak and submaximal PLC, leg vascular occlusion and ACE. But the values for VO2peak during FES isometric contractions combined with ACE is not significantly different from FES hybrid cycling.
2. Comparison of sub-maximal and peak VO2 values during arm crank (ACE) and wheelchair ergometry (WCE) in persons with spinal cord injury. The hypothesis is that wheelchair propulsion due to higher energy expenditure show higher work output and VO2peak than ACE.
3. Does 6 weeks of maximal strength training improve SCI subjects performance during WCE? WCE after 6 weeks maximal strength training is less strenuous owing to better work economy/ efficiency.
4. Effect from aerobic high intensity hybrid training on stroke volume (SV) and VO2peak in spinal cord injured men.

8 weeks of high intensity 4 times 4 interval training at 85-90% of peak heart rate during hybrid cycling. Hypothesis; VO2peak and SV will be significantly increased from training.

Inclusion Criteria:

• Paraplegia, sensorimotor complete injury AIS A to motor complete, sensory incomplete AIS B. Chronic neurological state with stabile spontaneous recovery compared to baseline AIS. At least year since injury.
• Be able to tolerate direct current stimulation in the means of FES
• Living in Health region IV and V, Norway.

Exclusion Criteria:

• Pacemaker (demand type)
• Known cancer
• Known pregnancy
• Severe autonomic dysreflexia
• Gross contractures