Cardiorespiratory and Metabolic Responses During FES Leg Exercise: Health and Fitness Benefits Update

SCIPA Switch-On: A Randomized Controlled Trial Investigating the Efficacy and Safety of Functional Electrical Stimulation–Assisted Cycling and Passive Cycling Initiated Early After Traumatic Spinal Cord Injury

Background. Substantial skeletal muscle atrophy after spinal cord injury (SCI) carries significant repercussions for functional recovery and longer-term health. Objective. To compare the efficacy, safety, and feasibility of functional electrical stimulation–assisted cycling (FESC) and passive cycling (PC) to attenuate muscle atrophy after acute SCI. Methods. This multicenter, assessor-blinded phase I/II trial randomized participants at 4 weeks post-SCI to FESC or PC (4 sessions per week, 1 hour maximum per session, over 12 weeks). The primary outcome measure was mean maximum cross-sectional area (CSA) of thigh and calf muscles (magnetic resonance imaging), and secondary outcome measures comprised body composition (dual energy X-ray absorptiometry), anthropometry, quality of life, and adverse events (AEs). Results. Of 24 participants, 19 completed the 12-week trial (10 FESC, 9 PC, 18 male). Those participants completed >80% of training sessions (FESC, 83.5%; PC, 85.9%). No significant between-group difference in postintervention muscle CSA was found. No significant between-group difference was found for any other tissue, anthropometric parameter, or behavioral variable or AEs. Six participants experienced thigh hypertrophy (FESC = 3; PC = 3). Atrophy was attenuated (<30%) in 15 cases (FESC = 7; PC = 8). Conclusions. Both cycle ergometry regimens examined were safe, feasible, and well tolerated early after SCI. No conclusions regarding efficacy can be drawn from our data. Further investigation of both modalities early after SCI is required.

Hybrid functional electrical stimulation exercise training alters the relationship between spinal cord injury level and aerobic capacity

OBJECTIVE

To test the hypothesis that hybrid functional electrical stimulation (FES) row training would improve aerobic capacity but that it would remain strongly linked to level of spinal cord lesion because of limited maximal ventilation.

DESIGN

Longitudinal before-after trial of 6 months of FES row training.

SETTING

Exercise for persons with disabilities program in a hospitaL.

PARTICIPANTS

Volunteers (N=14; age range, 21-63y) with complete spinal cord injury (SCI) (T3-11) who are >2 years postinjury.

INTERVENTION

Six months of FES row training preceded by a variable period of FES strength training.

MAIN OUTCOME MEASURES

Peak aerobic capacity and peak exercise ventilation before and after 6 months of FES row training.

RESULTS

FES row training significantly increased peak aerobic capacity and peak minute ventilation (both P<.05). Prior to FES row training, there was a close relation between level of SCI and peak aerobic capacity (adjusted R(2)=.40, P=.009) that was markedly reduced after FES row training (adjusted R(2)=.15, P=.10). In contrast, the relation between level of injury and peak minute ventilation was comparable before and after FES row training (adjusted R(2)=.38 vs .32, both P<.05).

CONCLUSIONS

The increased aerobic capacity reflects more than increased ventilation; FES row training effectively circumvents the effect of SCI on peak aerobic capacity by engaging more muscle mass for training, independent of the level of injury.