Effects of two different paradigms of electrical stimulation exercise on cardio-metabolic risk factors after spinal cord injury. A randomized clinical trial

Electrical stimulation paradigms on muscle quality and bone mineral density after spinal cord injury

The goal of the work was to determine the effects of altering muscle quality (peak torque and muscle CSA) via NMES-RT on bone mineral density (BMD) following application of FES-lower extremity cycling. Components of muscle quality were altered and attenuated the decline in BMD after SCI.

INTRODUCTION

Spinal cord injury (SCI) negatively impacts muscle quality and bone health. Neuromuscular electrical stimulation-resistance training (NMES-RT) has been shown to enhance muscle quality. It is unclear whether adding NMES-RT to functional electrical stimulation (FES)-lower extremity cycling may further augment muscle quality and subsequently enhance bone mineral density (BMD).

METHODS

Thirty-two participants were randomized into either 12 weeks of NMES-RT followed by 12 weeks of FES- lower extremity cycling (NMES-RT + FES; n = 16) or 12 weeks of passive movement training (PMT) followed by 12 weeks of FES-lower extremity cycling (PMT + FES; n = 16). Measurements were conducted at baseline (BL), post-interventions 1 and 2 (P1 and P2) separated evenly by 12 weeks. Left thigh muscle isometric and isokinetic torques were measured using an isokinetic dynamometer. Magnetic resonance imaging measured whole thigh and knee extensor (KE) muscle CSAs. Dual energy X-ray absorptiometry measured total and regional BMD.

RESULTS

NMES-RT elicited a trend towards greater isometric torque at 80 Hz (P = 0.057) and isokinetic torque (60 deg/s; P = 0.009 and 180 deg/s; P = 0.003) compared to PMT. Muscle CSA was greater in left whole thigh (F (2,20) = 9.1; P = 0.007) and KE (F (2,20) = 15.5; P = 0.001) by 11.0 and 8.0 cm2 respectively at P1 in the NMES-RT + FES compared to PMT + FES. In the NMES-RT + FES, ankle weights were positively associated with muscle CSA, isometric and isokinetic torques as well as muscle quality following P1. Compared to PMT + FES, NMES-RT + FES maintained BMD at the distal femur.

CONCLUSION

NMES-RT + FES enhanced muscle quality as measured by torque production and muscle CSA as result of increasing ankle weights. The addition of FES- lower extremity cycling to NMES-RT maintained but did not further augment muscle quality. Furthermore, NMES-RT + FES may help maintain BMD after SCI.

CLINICAL TRIAL REGISTRATION

Registered with clinicaltrials.gov: NCT02660073.

Recumbent FES-Cycling Exercise Improves Muscle Performance and Ambulation Capacity in Hospitalized Patients: A Randomized Controlled Trial

BACKGROUND

Acquired muscle weakness is a prevalent complication during hospitalization. Supportive technologies, such as functional electrical stimulation cycling (FES-cycling), are increasingly recognized as a tool with the potential to improve physical exercise in patients constrained to bed rest.

METHODS

In this randomized clinical trial, patients admitted to a high-complexity ward exhibiting clinical signs of muscle weakness (e.g., report of loss of strength, gait, or balance deficit due to weakness or restriction to bed) were enrolled. Participants were randomly allocated to a recumbent high-intensity, low-volume FES-cycling exercise or a control group. The primary outcomes measured were torque, power output, stimulation cost (neuromuscular efficiency), and ambulation capacity.

RESULTS

The analysis included 16 patients (eight in each group). Postintervention, the FES-cycling group presented a greater increase in both absolute (4.25 ± 3.15 vs. 0.04 ± 3.49 Nm, p = 0.02) and percentage torque (117 ± 88 vs. 8% ± 53%, p < 0.01) compared to the control. Similarly, the FES-cycling group presented higher absolute (3.91 ± 2.25 vs. 0.57 ± 1.82 watts, p < 0.01) and percentage power (61 ± 36 vs. 10% ± 23%, p < 0.01), along with a higher absolute (-2903 ± 2598 vs. -523 ± 1319 μC/watt, p = 0.03) and percentage stimulation cost (-33 ± 18 vs. -6% ± 1 8%, p = 0.01). Additionally, enhanced ambulation capacity was observed in the FES-cycling group, with 6 patients showing improvement versus 2 in the control group (p = 0.03).

CONCLUSIONS

Recumbent high-intensity, low-volume FES-cycling exercise increased muscle strength, power, and neuromuscular efficiency in hospitalized patients with muscle weakness. Improvements in ambulation capacity were also noted, supporting the intervention potential.

Activity-based recovery training with spinal cord epidural stimulation improves standing performance in cervical spinal cord injury

BACKGROUND

Individuals with a clinically complete spinal cord injury are unable to stand independently without external assistance. Studies have shown the combination of spinal cord epidural stimulation (scES) targeted for standing with activity-based recovery training (ABRT) can promote independence of standing in individuals with spinal cord injury. This cohort study aimed to assess the effects of stand-ABRT with scES in individuals with cervical chronic spinal cord injury. We evaluated the ability of these individuals to stand independently from physical assistance across multiple sessions.

METHODS

Thirty individuals participated in this study, all unable to stand independently at the start of the intervention. Individuals were participating in a randomized clinical trial and received stand-ABRT in addition to targeted cardiovascular scES or voluntary scES. During the standing intervention, participants were asked to stand 2 h a day, 5 days a week for 80 sessions (Groups 1 and 2) or 160 sessions (Groups 3 and 4).

RESULTS

A total of 3,524 training days were considered for analysis. Group 1 had 507 days, group 2 with 578 days, and 1152 and 1269 days for groups 3 and 4 respectively. 71% of sessions reached the two-hour standing goal. All individuals achieved outcomes of lower limb independent extension with spinal cord epidural stimulation, with a wide range throughout a training day. Sixteen participants achieved unassisted hip extension while maintaining unassisted bilateral knee and trunk extension. Participants receiving initial voluntary scES training performed better in unassisted bilateral knee and trunk extension than those receiving initial cardiovascular scES. The lower-limb standing activation pattern changes were consistent with the greater standing independence observed by all groups.

CONCLUSIONS

Individuals with chronic cervical spinal cord injury were able to achieve various levels of extension without manual assistance during standing with balance assist following stand-ABRT with scES. These results provide evidence that scES modulates network excitability of the injured spinal cord to allow for the integration of afferent and supraspinal descending input to promote standing in individuals with spinal cord injury.

TRIAL REGISTRATION

The study was registered on Clinical Trials.gov (NCT03364660) prior to subject enrollment.

Can Lifestyle and Behavioral Interventions Improve Weight Management in Individuals With Spinal Cord Injury? A Systematic Review and Meta-analysis

OBJECTIVE

To evaluate the effect of lifestyle and behavioral interventions on anthropometric indices and body composition in individuals with spinal cord injury (SCI).

DATA SOURCES

MEDLINE, EMBASE, Web of Science, and Cochrane Library were searched from inception to January 22, 2024.

STUDY SELECTION

Randomized controlled trials (RCTs), non-RCTs, and pre-post studies on the effectiveness of lifestyle and/or behavioral interventions in improving body composition (including body mass index, waist circumference, fat mass, and lean mass) were eligible.

DATA EXTRACTION

Study design characteristics, number of participants, intervention/control characteristics, and outcomes were extracted.

DATA SYNTHESIS

Sixty-one interventional studies were included in the systematic review, among which 5 RCTs contributed to meta-analysis. Exercise, alone or combined with functional electrical stimulation (FES), supplements, or educational sessions, was the most studied intervention across the identified studies, accounting for 75% of studies. Exercise regimen compared with the usual activities yielded a decrease in BMI (mean difference [MD], -0.38 kg/m2; 95% CI, -0.57 to -0.19; I2: 0%; Pq:.45]) and waist circumference (MD, -2.93 cm; 95% CI, -3.98 to -1.88; I2: 0%; Pq: 0.59). No significant differences were observed when comparing changes in total body fat percentage nor lean body mass between the 2 groups. Exercise with FES and testosterone, exercise and personalized diet, high-protein diet, and α-lipoic acid supplementation were mapped as other potentially beneficial interventions, whereas studies targeting behavioral changes were inconclusive.

CONCLUSIONS

Exercise-based interventions alone or combined with FES or standardized/personalized dietary regimens show promise as effective strategies for improving anthropometric indices and body composition among individuals with SCI, emphasizing the potential benefit of the weight management program. The present findings may not be applicable to individuals with high SCI lesions. Further research to evaluate the effectiveness of a more complex lifestyle and/or behavioral interventions in individuals with SCI is warranted.

Skeletal muscle hypertrophy and enhanced mitochondrial bioenergetics following electrical stimulation exercises in spinal cord injury: a randomized clinical trial

We examined the combined effects of neuromuscular electrical stimulation-resistance training (NMES-RT) and functional electrical stimulation-lower extremity cycling (FES-LEC) compared to passive movement training (PMT) and FES-LEC on mitochondrial electron transport chain (ETC) complexes and citrate synthase (CS) in adults with SCI. Thirty-two participants with chronic SCI were randomized to 24 weeks of NMES-RT + FES [n = 16 (14 males and 2 females) with an age range of 20-54 years old] or PMT + FES [n = 16 (12 males and 4 females) with an age range of 21-61 years old]. The NMES-RT + FES group underwent 12 weeks of surface NMES-RT using ankle weights followed by an additional 12 weeks of FES-LEC. The PMT + FES performed 12 weeks of passive leg extension movements followed by an additional 12 weeks of FES-LEC. Using repeated measures design, muscle biopsies of the vastus lateralis were performed at baseline (BL), post-intervention 1 (P1) and post-intervention 2 (P2). Spectrophotometer was used to measure ETC complexes (I-III) and CS using aliquots of the homogenized muscle tissue. Magnetic resonance imaging was used to measure skeletal muscle CSAs. A time effect was noted on CS (P = 0.001) with an interaction between both groups (P = 0.01). 46% of the participants per group had zero activities of CI without any changes following both interventions. A time effect was noted in CII (P = 0.023) following both interventions. Finally, NMES-RT + FES increased CIII at P1 compared to BL (P = 0.023) without additional changes in P2 or following PMT + FES intervention. Skeletal muscle hypertrophy may potentially enhance mitochondrial bioenergetics after SCI. NMES-RT is likely to enhance the activities of complex III in sedentary persons with SCI. Clinical trials # NCT02660073.

Multiparametric MRI Assessment of Morpho-Functional Muscle Changes Following a 6-Month FES-Cycling Training Program: Pilot Study in People With a Complete Spinal Cord Injury

Background

Spinal cord injuries (SCIs) cause debilitating secondary conditions such as severe muscle deterioration, cardiovascular, and metabolic dysfunctions, significantly impacting patients' quality of life. Functional electrical stimulation (FES) combined with cycling exercise (FES-cycling) has shown promise in improving muscle function and health in individuals with SCI.

Objective

This pilot study aimed to investigate the potential role of multiparametric magnetic resonance imaging (MRI) to assess muscle health during and after an FES-cycling rehabilitation program.

Methods

Four male participants with chronic SCI underwent a 6-month FES-cycling training program, consisting of two 30-minute sessions per week. MRI scans were performed at baseline (T0), after 3 months (T1), at the end of the training (T2), and 1-month posttraining (T3). The MRI protocol included T1-weighted imaging for volume quantification, Dixon imaging for fat fraction, multi-echo spin echo for T2 relaxation times, and diffusion tensor imaging to assess diffusion parameters.

Results

Muscle hypertrophy was observed, with an average increase in muscle volume of 22.3% at T1 and 36.7% at T2 compared with baseline. One month posttraining, muscle volume remained 23.2% higher than baseline. Fat fraction decreased from 11.1% at T0 to 9.1% at T2, with a rebound to 10.9% at T3. T2 relaxation times showed a reduction even though this was not consistent among participants. Diffusion tensor imaging parameters revealed subtle changes in muscle tissue microstructure, with a decrease in fractional anisotropy mainly associated to an increase of radial diffusivity.

Conclusions

Although preliminary, this study provides evidence that 6 months of low-intensity FES-bike training can increase muscle volume and decrease fat infiltration in individuals with SCI. The study demonstrates that the use of a multiparametric MRI provides comprehensive insights into both macroscopic and microscopic changes within muscle tissues, supporting its integration into clinical practice for assessing the efficacy of rehabilitation interventions.

The Clinical Management of Electrical Stimulation Therapies in the Rehabilitation of Individuals with Spinal Cord Injuries

Background: People with spinal cord injuries (SCIs) often have trouble remaining active because of paralysis. In the past, exercise recommendations focused on the non-paralyzed muscles in the arms, which provides limited benefits. However, recent studies show that electrical stimulation can help engage the paralyzed extremities, expanding the available muscle mass for exercise. Methods: The authors provide an evidence-based approach using expertise from diverse fields, supplemented by evidence from key studies toward the management of electrical stimulation therapies in individuals with SCIs. Literature searches were performed separately using the PubMed, Medline, and Google Scholar search engines. The keywords used for the searches included functional electrical stimulation cycling, hybrid cycling, neuromuscular electrical stimulation exercise, spinal cord injury, cardiovascular health, metabolic health, muscle strength, muscle mass, bone mass, upper limb treatment, diagnostic and prognostic use of functional electrical stimulation, tetraplegic hands, and hand deformities after SCI. The authors recently presented this information in a workshop at a major rehabilitation conference. Additional information beyond what was presented at the workshop was added for the writing of this paper. Results: Functional electrical stimulation (FES) cycling can improve aerobic fitness and reduce the risk of cardiovascular and metabolic diseases. The evidence indicates that while both FES leg cycling and neuromuscular electrical stimulation (NMES) resistance training can increase muscle strength and mass, NMES resistance training has been shown to be more effective for producing muscle hypertrophy in individual muscle groups. The response to the electrical stimulation of muscles can also help in the diagnosis and prognosis of hand dysfunction after tetraplegia. Conclusions: Electrical stimulation activities are safe and effective methods for exercise and testing for motor neuron lesions in individuals with SCIs and other paralytic or paretic conditions. They should be considered part of a comprehensive rehabilitation program in diagnosing, prognosing, and treating individuals with SCIs to improve function, physical activity, and overall health.

Basal Metabolic Rate Versus Dietary Vitamin D and Calcium Intakes and the Association With Body Composition and Bone Health After Chronic Spinal Cord Injury

We examined the association among basal metabolic rate (BMR) as well as dietary intakes of vitamin D (Vit D) and calcium on body composition and bone mineral density (BMD) after spinal cord injury (SCI). Cross-sectional design. Veterans Affairs Medical Center, Richmond, VA. About 33 individuals with chronic SCI who recorded their food consumption 3 days per week for 2 weeks. BMR was measured after 10 to 12 h of overnight fast. Average daily vit D and calcium intakes, and total caloric intake were recorded and analyzed using the Nutrition Data System for Research (NDSR) software. Fasting blood analysis for 25-hydroxyvitamin D (25[OH]D) status and Triiodothyronine (T3) status was performed (n = 10). Total and regional BMD, % fat mass (FM), and % lean mass (LM) were measured by dual X-ray absorptiometry scans. Participants consumed less than the Institute of Medicine (IOM) recommended daily allowances (RDA) for vit D (600-800 IU) and calcium (1000-1200 mg) for adults. BMR was positively related to total-lean mass (r = .62, P = .0001; n = 32) and leg-lean mass (r = .51, P = .003; n = 32). Adjusted BMR was negatively related to BMD of the left (r = -.38, P = .047; n = 28) and the right (r = -.41, P = .032; n = 28) proximal tibia. Vit D intake was negatively related to percentage total-FM (r = -.33, P = .07; n = 29) and legs-%FM (r = -.37, P = .047; n = 29). Multivariate regression models indicated that adjusted BMR explained the variance in leg fat mass (34%; P = .002) and percentage fat mass (44%; P < .0001). Persons with SCI are likely to consume less than the RDAs for vit D and calcium. BMR may explain the changes in body composition and bone metabolism. Dietary vit D should be considered as a prophylactic intervention in maintenance of bone health after SCI.