Neuromuscular electrical stimulation for preventing skeletal-muscle weakness and wasting in critically ill patients:a systematic review

BACKGROUND: Neuromuscular electrical stimulation (NMES) therapy may be useful in early musculoskeletal rehabilitation during acute critical illness. The objective of this systematic review was to evaluate the effectiveness of NMES for preventing skeletal-muscle weakness and wasting in critically ill patients, in comparison with usual care. METHODS: We searched PubMed, CENTRAL, CINAHL, Web of Science, and PEDro to identify randomized controlled trials exploring the effect of NMES in critically ill patients, which had a well-defined NMES protocol, provided outcomes related to skeletal-muscle strength and/or mass, and for which full text was available. Two independent reviewers extracted data on muscle-related outcomes (strength and mass), and participant and intervention characteristics, and assessed the methodological quality of the studies. Owing to the lack of means and standard deviations (SDs) in some studies, as well as the lack of baseline measurements in two studies, it was impossible to conduct a full meta-analysis. When means and SDs were provided, the effect sizes of individual outcomes were calculated, and otherwise, a qualitative analysis was performed. RESULTS: The search yielded 8 eligible studies involving 172 patients. The methodological quality of the studies was moderate to high. Five studies reported an increase in strength or better preservation of strength with NMES, with one study having a large effect size. Two studies found better preservation of muscle mass with NMES, with small to moderate effect sizes, while no significant benefits were found in two other studies. CONCLUSIONS: NMES added to usual care proved to be more effective than usual care alone for preventing skeletal-muscle weakness in critically ill patients. However, there is inconclusive evidence for its benefit in prevention of muscle wasting

Motor Skill Acquisition and Retention after Somatosensory Electrical Stimulation in Healthy Humans

Somatosensory electrical stimulation (SES) can increase motor performance, presumably through a modulation of neuronal excitability. Because the effects of SES can outlast the period of stimulation, we examined the possibility that SES can also enhance the retention of motor performance, motor memory consolidation, after 24 hours (Day 2) and 7 days (Day 7), that such effects would be scaled by SES duration, and that such effects were mediated by changes in aspects of corticospinal excitability, short-interval intracortical inhibition (SICI), and intracortical facilitation (ICF). Healthy young adults (n = 40) received either 20 (SES-20), 40 (SES-40), or 60 minutes (SES-60) of real SES, or sham SES (SES-0). The results showed SES-20 increased visuomotor performance on Day 2 (15%) and Day 7 (17%) and SES-60 increased visuomotor performance on Day 7 (11%; all p < 0.05) compared with SES-0. Specific responses to transcranial magnetic stimulation (TMS) increased immediately after SES (p < 0.05) but not on Days 2 and 7. In addition, changes in behavioral and neurophysiological parameters did not correlate, suggesting that paths and structures other than the ones TMS can assay must be (also) involved in the increases in visuomotor performance after SES. As examined in the present study, low-intensity peripheral electrical nerve stimulation did not have acute effects on healthy adults’ visuomotor performance but SES had delayed effects in the form of enhanced motor memory consolidation that were not scaled by the duration of SES

Electromyostimulation and plyometric training effects on jumping and sprint time

P. 533-539Este estudio comparó los efectos de los períodos de entrenamiento de cuatro semanas de electroestimulación (EMS), entrenamiento pliométrico (P) o entrenamiento combinado de EMS y P de los músculos extensores de la rodilla en 20 m de velocidad (ST), capacidad de salto (SJ y CMJ), máximo de fuerza isométrica (MVC) y área de sección transversal muscular (CSA). Métodos: Cuarenta sujetos fueron asignados aleatoriamente a uno de los cuatro grupos de tratamiento: electroestimulación (EG); pliométrico (PG); EMG y P combinados (EPG); y un grupo de control (CG) que realizó 4 veces por semana. Los sujetos fueron evaluados antes y después del programa de entrenamiento, así como una vez más después de 2 semanas de desentrenamiento. Resultados: se observó un aumento significativo (p <0.05) en ST después del entrenamiento (2.4%) en EG, mientras que se observó una disminución significativa (p <0.05) (-2.3%) en EPG. Se observaron aumentos significativos en la EPG (p <0.05) en SJ (7.5%) y CMJ (7.3%) después del entrenamiento, mientras que no se observaron cambios significativos en ambos saltos después del entrenamiento y el desentrenamiento para EG. Se observó un aumento significativo (p <0.05) en MVC después del entrenamiento (9.1%) y después de desentrenar (8.1%) en EG. Se observó un aumento significativo (p <0.05) en MVC después del entrenamiento (16.3%). Se observó un aumento significativo (p <0.01) en CSA después del entrenamiento en EG (9.0%) y en EPG (7.1%). Conclusión: EMS combinado con entrenamiento pliométrico aumentó la altura de salto y la carrera rápida en hombres físicamente activos. Además, el EMS solo o EMS combinado con entrenamiento pliométrico conduce a aumentar la fuerza máxima y a cierta hipertrofia de los músculos entrenados. Sin embargo, solo el entrenamiento de EMS no produjo ninguna mejora en el desarrollo de fuerza explosiva de salto o incluso pudo interferir en la carrera de velocidadS

Acute Effects of Neuromuscular Electrical Stimulation on Contralateral Plantar Flexor Neuromuscular Function

Contralateral facilitation, i.e., the increase in contralateral maximal voluntary strength that is observed when neuromuscular electrical stimulation (NMES) is applied to the ipsilateral homonymous muscle, has previously been reported for the knee extensors but the neurophysiological mechanisms remain to be investigated. The aim of this study was to compare plantar flexor contralateral facilitation between a submaximal voluntary contraction (~10% MVC torque) and two evoked contractions (conventional and wide-pulse high-frequency NMES) of the ipsilateral plantar flexors, with respect to a resting condition. Contralateral MVC torque and voluntary activation level were measured in 22 healthy participants while the ipsilateral plantar flexors were at rest, voluntarily contracted or stimulated for 15 s. Additional neurophysiological parameters (soleus H-reflex and V-wave amplitude and tibialis anterior coactivation level) were quantified in a subgroup of 12 participants. Conventional and wide-pulse high-frequency NMES of the ipsilateral plantar flexors did not induce any contralateral facilitation of maximal voluntary strength and activation with respect to the resting condition. Similarly, no alteration of neurophysiological parameters was observed in the different conditions. This absence of contralateral facilitation contrasts with some results previously obtained on the knee extensors but is consistent with the absence of neurophysiological changes on the contralateral soleus

Rate of force development as an indicator of neuromuscular fatigue: a scoping review

Because rate of force development (RFD) is an emerging outcome measure for the assessment of neuromuscular function in unfatigued conditions, and it represents a valid alternative/complement to the classical evaluation of pure maximal strength, this scoping review aimed to map the available evidence regarding RFD as an indicator of neuromuscular fatigue. Thus, following a general overview of the main studies published on this topic, we arbitrarily compared the amount of neuromuscular fatigue between the "gold standard" measure (maximal voluntary force, MVF) and peak, early (≤100 ms) and late (&gt;100 ms) RFD. Seventy full-text articles were included in the review. The most-common fatiguing exercises were resistance exercises (37% of the studies), endurance exercises/locomotor activities (23%), isokinetic contractions (17%), and simulated/real sport situations (13%). The most widely tested tasks were knee extension (60%) and plantar flexion (10%). The reason (i.e., rationale) for evaluating RFD was lacking in 36% of the studies. On average, the amount of fatigue for MVF (-19%) was comparable to late RFD (-19%) but lower compared to both peak RFD (-25%) and early RFD (-23%). Even if the rationale for evaluating RFD in the fatigued state was often lacking and the specificity between test task and fatiguing exercise characteristics was not always respected in the included studies, RFD seems to be a valid indicator of neuromuscular fatigue. Based on our arbitrary analyses, peak RFD and early phase RFD appear even to be more sensitive to quantify neuromuscular fatigue than MVF and late phase RFD

Enhancing adaptions to neuromuscular electrical stimulation training interventions

Neuromuscular electrical stimulation (NMES) applied to skeletal muscles is an effective rehabilitation and exercise training modality. However, the relatively low muscle force and rapid muscle fatigue induced by NMES limit the stimulus provided to the neuromuscular system and subsequent adaptations. We hypothesize that adaptations to NMES will be enhanced by the use of specific stimulation protocols and adjuvant interventions

Strength, jumping and change of direction speed asymmetries in soccer, basketball and tennis players

Despite growing research in the field of inter-limb asymmetries (ILAs), little is known about the variation of ILAs in different populations of athletes. The purpose of this study was to compare ILAs among young basketball, soccer and tennis players. ILAs were assessed in three different types of tests (strength, jumping and change of direction (CoD) speed), each including different tasks: (1) bilateral and unilateral counter movement jump, (2) isometric strength of knee extensors (KE) and knee flexors (KF), and (3) 90° and 180° CoD. Generally, the absolute metrics showed strong reliability and revealed significant differences (p < 0.05) among the three groups in KE maximal torque, KE and KF rate of force development and in both CoD tests. For jumping ILAs, power and force impulse metrics exhibited significant between-limb differences between groups, compared to jump height. For strength and CoD speed ILAs, only KF maximal torque and 180° CoD exhibited significant differences between groups. Greater KF strength ILAs in soccer players and counter-movement jump ILAs in tennis players are most probably the result of sport-specific movement patterns and training routines. Sport practitioners should be aware of the differences in ILAs among sports and address training programs accordingly

Epidemiology of traumatic and overuse injuries in Swiss professional male ice hockey players

Background: Ice hockey injury patterns in Europe were last evaluated in the 1990s. Purpose: The aim of this study was to assess the frequency, type, location, and incidence of traumatic injuries, as well as the prevalence and relative effect of overuse injuries in professional male ice hockey players. Study Design: Descriptive epidemiology study. Methods: Traumatic injuries were assessed using a standardized injury report form over a 1-year period (including the preparatory phase and season). The Oslo Sports Trauma Research Centre Overuse Injury Questionnaire was used to determine overall and substantial overuse injuries and their relative effect on ice hockey players. Results: Five Swiss National League teams participated in the study. From a total of 321 recorded injuries, 179 led to time loss from sport. The game-related time-loss injury incidence during the season was 88.6/1000 player-game hours.Time-loss injuries affected mainly the hip/groin/thigh region (23%), followed by the head (17%). Most time-loss injuries were classified as muscle strains (24%), followed by concussions (18%). The most common injury mechanism involved collision with an opponent’s body (31%), and right forward players (23%) were most likely to report a game-related injury. Most injuries (27%) occurred within the defending zone along the boards. The average prevalence rates of all overuse and substantial overuse injuries were 49% and 13%, respectively. The hip/groin displayed the highest average prevalence for all overuse problems (16%), translating to the highest relative effect. Conclusion: Muscle strains and concussions were the most frequent time-loss injuries in Swiss professional ice hockey players. The hip/groin was the most affected region for both traumatic and overuse injuries