Faghri & Yount 2002; USA
PEDro=5
RCT
N=29

Population: 7 subjects with paraplegia, 7 with tetraplegia; 4 incomplete and 10 complete injuries; 15 able-bodied controls.
Treatment: Random order of standing with or without FES (30 mins) for SCI subjects; voluntary tiptoe contractions during 30 minutes standing for able-bodied subjects.
Outcome Measures: Hemodynamics during supine-sitting-30 min standing.

1. Reductions (p < 0.05) up to 10% BP measures for SCI subjects from sitting to passive standing; but minimal changes when moving to FES standing.
2. After 30 min of passive standing (no FES), there is a reduction in stroke volume and cardiac output.  After 30 min of FES standing, the pre-standing haemodynamics are maintained except for a significant reduction in stroke volume.

Elokda et al. 2000; USA
PEDro=3
RCT
N=5

Population: 2 subjects with tetraplegia, 3 with paraplegia; all complete injuries; 2-4 weeks post-injury.
Treatment: Tilt table - 6 minutes at each tilt angle (0, 15, 30, 45 and 60 degrees), with 4 minutes of recovery between each, with or without bilateral ankle plantar flexor and knee extensor electrical stimulation. Application order or absence of FNS was counterbalanced.
Outcome Measures: HR, blood pressure, perceived exertion.

1. At tilt angles of 15, 30, 45 and 60 degrees, systolic BP was significantly lower when FNS was not applied compared to when it was administered, and it was more marked with increasing tilt angles.
2. There was a progressive decrease in blood pressures with increasing tilt angle and this increase was less pronounced in the FNS condition.
3. Post hoc analysis showed that HR was significantly higher with FNS compared to without FNS at 60 degrees tilt.

Sampson et al. 2000; USA
PEDro=3
RCT
N=6

Population: Motor complete SCI (lesions above T6); 3 with recent injury, 3 with long standing injury
Treatment: With and without lower-extremity FES while tilted by 10º increments every 3 minutes, from 0-90º with varying intensities of stimulation.
Outcome Measures: Blood pressure, heart rate, perceived syncope score.

1. ↑HR increased for both groups with ↑ incline angle.  Mean diastolic BP was lower for the recent SCI subjects (105 mmHg) with compared with chronic (123 mmHg).
2. ↑systolic and diastolic BP with ↑stimulation intensities and ↓BP with ↑incline angle (p < .001) regardless of the site of stimulation. 
3. Subjects tolerated higher angles of incline with FES than without. The higher the intensity of FES, regardless of stimulation site, the greater the tilt incline tolerated.

Raymond et al. 2002; Australia
Downs & Black=12
Prospective Controlled Trial
N=16

Population: 8 male subjects with complete paraplegia, 8 male able-bodied controls
Treatment: Lower-body negative pressure (LBNP) was used to provide the orthostatic challenge. Subjects were evaluated: (1) during supine rest, (2) supine with submaximal arm crank exercises (ACE), (3) ACE+LBNP, and (4) for SCI only, ACE+LBNP+leg electrical stimulation (ES).
Outcome measures: Heart rate, stroke volume, cardiac output.

1. ES increased stroke volume from ACE+LBNP to ACE+LBNP+ES for both SCI and able-bodied groups. ES did not affect oxygen uptake or cardiac output.  

Faghri et al. 2001; USA
Downs & Black=21
Prospective Controlled Trial
N=14

Population : 7 subjects with tetraplegia, 7 with paraplegia; 4 incomplete and 10 complete injuries.
Treatment: FES augmented standing (active) and non-FES standing (passive), for 30min duration; tests were separated by at least 24hours.
Outcome Measures: Hemodynamics.

1. BP changed 8-9% when moving from sitting to passive standing (no FES).  The augmented FES condition prevented BP change when moving from sitting to standing. 

Faghri et al. 1992; USA
Downs & Black=11
Pre-post
N=13

Population: 6 subjects with paraplegia (T4-T10); 7 subjects with tetraplegia (C4-C7)
Treatment: FES-leg cycle ergometer training, 3X/week, for about 12 weeks (36 sessions).
Outcome Measures: Oxygen uptake, pulmonary ventilation (VE), respiratory exchange ratio (RER), BP, HR, stroke volume (SV) and cardiac output (Q).

1. After training, ↑ resting HR and systolic BP in subjects with tetraplegia and ↓systolic and diastolic BP in subjects with paraplegia.
2. In both groups, HR and BP during submaximal exercise significantly decreased and stroke volume and cardiac output significantly increased after program.
3. These results suggest that FES-LCE training improves peripheral muscular and central cardiovascular fitness in SCI subjects.

Davis et al.1990; USA
Downs & Black score=16
Pre-post
N=12

Population:  12 males subjects with, paraplegiacs (T5-L2); FES Group, n=6; Non-FES (Control) group, n=6.
Treatment: Sub-maximal and maximal arm-crank exercise with or without functional neuromuscular stimulation (FNS) of paralyzed leg muscles. 
Outcome Measures: PeakVO2, expired ventilation (VE), perceived exertion respiratory exchange ratio (RER), BP, HR, resting stroke volume (SV) and cardiac output (Q), total peripheral resistance.

1. No significant differences between the FES and Control groups in terms of peak VO2 (2.09 l/min), maximal HR, VE, respiratory exchange ratio and perceived exertion.
2. No differences of power output or VO2 during peripheral FNS application but stroke volume and Q were higher during the FNS- induced leg contractions on R subjects. Neither rest of exercise HR was significantly influenced by lower limb FNS in FES group. Increase of peripheral and overall ratings of perceived exertion.
3. HR, SV and Q were not significantly altered at rest or during hybrid exercise in Control group. Decrease of peripheral and overall ratings of perceived exertion.

4. No changes in BP, impedance indexes of myocardial contractility and differentiated subjective ratings of perceived exertion during hybrid exercise compared with non-FNS conditions.

Chao & Cheing 2005; China
Downs & Black=16
Post-test
N=16

Population: Motor complete tetraplegia Treatment: Progressive head-up tilting maneuver with and without the FES to 4 muscle groups.
Outcome Measures: BP, heart rate, perceived presyncope score.

1. With increasing tilt angle, ↓ systolic and diastolic BP and ↑heart rate with and without FES.
2. Adding FES to tilting significantly attenuated the drop in systolic BP by 3.7±1.1 mmHg (p = .005), the drop in diastolic BP by 2.3±0.9 mmHg (P = .018), and heart rate increase by 1.0±0.5 beats/min (p = .039) for every 15 degrees increment in the tilt angle.
3. FES increased the overall mean standing time by 14.3±3.9 min (p = .003).