Tai Chi exercise and functional electrical stimulation of lower limb muscles for rehabilitation in older adults with chronic systolic heart failure: a non-randomized clinical trial

Exercise-based training decreases hospitalizations in heart failure patients but such patients have exercise intolerance. The objectives of the study were to evaluate the effect of 12 weeks of Tai Chi exercise and lower limb muscles' functional electrical stimulation in older chronic heart failure adults. A total of 1,084 older adults with chronic systolic heart failure were included in a non-randomized clinical trial (n=271 per group). The control group did not receive any kind of intervention, one group received functional electrical stimulation of lower limb muscles (FES group), another group practiced Tai Chi exercise (TCE group), and another received functional electrical stimulation of lower limb muscles and practiced Tai Chi exercise (FES & TCE group). Quality of life and cardiorespiratory functions of all patients were evaluated. Compared to the control group, only FES group had increased Kansas City Cardiomyopathy Questionnaire (KCCQ) score (P<0.0001, q=9.06), only the TCE group had decreased heart rate (P<0.0001, q=5.72), and decreased peak oxygen consumption was reported in the TCE group (P<0.0001, q=9.15) and FES & TCE group (P<0.0001, q=10.69). FES of lower limb muscles and Tai Chi exercise can recover the quality of life and cardiorespiratory functions of older chronic heart failure adults (trial registration: Research Registry 4474, January 1, 2015).

Electromyographic analysis of the gait cycle phases of boxer dogs / Análise eletromiográfica do ciclo de marcha em cães da raça boxer

Systematic studies involving technologies such as surface electromyography (sEMG) may provide important data that enable veterinarians to recognize musculoskeletal, ligamentous, and neurological alterations. The aim of this study was to describe the gait cycle phases and the timing of muscle activation in healthy Boxer dogs during gait by means of sEMG. The gait cycle of seven Boxer dogs was evaluated and sEMG was recorded from the biceps brachii, triceps brachii, brachiocephalic, rectus femoris, semitendinosus, semimembranosus, and superficial gluteal muscles of the right hemibody. Circular monopolar Ag/AgCl electrodes were attached to the mean point between the motor point and the muscle insertion. The electromyographic signals were collected by an active interface with 20-fold gain in a bipolar differential configuration using a 16-channel signal conditioner (EMG Systems Brasil), while the dogs walked on a treadmill at a speed of 2m/s. Pearson's correlation was used for the statistical analysis. A positive correlation was found between the rectus femoris and biceps brachii (r= 0.81); superficial gluteal and triceps brachii (r= 0.69); semitendinosus-semimembranosus and biceps brachii (r= 0.76); and rectus femoris and semitendinosus and semimembranosus muscle groups (r=0.99). The biceps brachii and brachiocephalic muscles work in tandem to position the thoracic limb during the gait cycle, while the semitendinosus-semimembranosus group flexes the knee and, simultaneously with the quadriceps that flexes the hip, prevents the contact of the pelvic limb with the ground during the swing phase. The body is propelled forward by the triceps brachii muscle, which extends the elbow and flexes the shoulder at the final contact, while the superficial gluteal muscle extends the hip.(AU)

Estudos sistemáticos que envolvem uso de tecnologias, como a eletromiografia de superfície (EMGs), podem fornecer dados importantes que capacitam os clínicos a diferenciar as alterações musculoesqueléticas, ligamentares ou neurológicas. Objetiva-se com este trabalho descrever as fases da marcha canina e o momento de ativação dos músculos de cães saudáveis da raça Boxer durante a marcha, por meio da eletromiografia de superfície. Avaliou-se a marcha de sete cães da raça Boxer, e o sinal elétrico da eletromiografia de superfície foi coletado do bíceps braquial, do tríceps braquial, do braquiocefálico, do reto femoral, do semitendinoso/semimembranoso e do glúteo superficial do hemicorpo direito. Os eletrodos monopolares circulares de prata com cloreto de prata (Ag/AgCl) foram posicionados no ponto médio entre a placa motora e a inserção desses músculos. Os sinais eletromiográficos foram capturados e adquiridos por uma interface ativa com ganho de 20x em configuração diferencial bipolar e por um condicionador de sinais (EMG Systems Brasil) de 16 canais, enquanto os cães caminharam em esteira com velocidade de 2m/s. Para análise estatística, foi aplicado teste de correlação de Pearson. Verificou-se correlação positiva entre os músculos retofemoral e bíceps braquial (r= 0,81); glúteo superficial e tríceps braquial (r= 0,69); semitendinoso/semimembranoso e bíceps braquial (r= 0,76); e entre o músculo reto femoral e o grupo muscular semitendinoso e semimembranoso (r=0,99). Os músculos bíceps braquial e braquiocefálico do mesmo membro trabalham em sinergia para posicionar o membro torácico durante o ciclo de marcha, enquanto o grupo muscular semitendinoso/semimembranoso flexiona o joelho e, simultaneamente com o quadríceps, que flexiona o quadril, impede que o membro pélvico entre em contato com o solo no balanço. Para impulsionar o corpo à frente, o músculo tríceps braquial estende o cotovelo e flexiona o ombro no contato final e o glúteo superficial estende o quadril.(AU)

Characteristics of Dynamic Contractions on Surface Electromyography Single of Stroke Patients Induced from Low Limb Muscle When Exercising Passively, Exercising Initiatively with Assitant and Against Resistance / 中国康复理论与实践

@#Objective To investigate the characteristics of the dynamic contractions on the surface electromyography (sEMG) single of stroke patients induced from the low limb muscle when exercising passively, exercising initiatively with assistant and against resistance.Methods 24 stroke patients with hemiplegia and 17 normal subjects were tested with sEMG under a dynamic contractions in coxa and knee flexion and extension passively, initiatively with assistant and against resistance. The myoelectric signals were collected and processed by linear time and frequency domain method.Results The values of median frequency (MF) and mean power frequency (MPF) of stroke group were significantly lower, but the value of average EMG (AEMG) was higher ( P<0.001). The values of MF and MPF in activity side were lower than that in non-activity side ( P<0.001). The values of MF and MPF when exercising passively were higher than that when exercising with resistance ( P<0.05). The value of AEMG when exercising with resistance was highest. The values of MF and MPF in the synergist muscle were higher. The values of AEMG in the antagonistic muscle and synergist muscle were higher than that agonist and synergist muscle ( P<0.01). The values of MF and MPF in non-paretic exercising side were higher significantly, but in paretic exercising side and non-paretic silent side were lower. The values of MF and MPF in exercising side from vastus lateralis (VL) were the highest. The values of AEMG in exercising side and non-exercising side from biceps femoris (BF) were the highest. The values of MF and MPF in low limb of stroke group reduced, that in rectus femoris (RF) from paretic side was the lowest; that in BF from non-paretic side was the lowest ( P<0.01). The value of AEMG in low limb of stroke group was high significantly, especially in BF from the low limb of the non-paretic side in stroke patients. The values of AEMG in four group muscles gradually were higher following the higher exercising load, and that in the BF was the highest, and that in vastus medialis (VM) rose significantly.Conclusion The values of MF and MPF of stroke patients with hemiplegia reduce significantly, but the value of AEMG is higher. The values of MF and MPF in exercising side are lower than that in non-exercising side and non-paretic exercising side rising significantly, but that in paretic exercising side and non-paretic silent side reduce significantly. The values of MF and MPF in assistant exercise are higher than that in passive exercise and resistance exercise, but the value of AEMG in resistance exercise is higher than that in assistant exercise and in passive exercise. The values of MF and MPF in synergist muscle rise, but the values of AEMG in antagonist and synergist muscle are higher than that agonist and synergist muscle.

The sEMG Characteristics of the Lower Limbs Muscles in Stroke Patients / 中国运动医学杂志

Objective To observe the surface electromyogram(sEMG)characteristics of the lower limbs muscles in stroke patients and healthy subjects during the passive and active-assisted anti-resistance movements.Methods Twenty four stroke patients and 17 healthy individuals(control group) participated in this study.sEMG of rectus femoris(RF),vastus lateralis(VL),ventralis medialis(VM)and biceps femoris(BF)was recorded during passive and active-assisted anti-resistance of knee joint in both groups.Average EMG(AEMG),mean power frequency(MPF)and median frequency(MF) were analyzed.Results Multiple factor ANOVA showed that very significant differences in the values of MF,MPF and AEMG between non-paretic and the paretic limbs appeared(P

The Neuromuscular Blocking Effects of Aminoglycoside Antibiotics on Diaphragm and Limb Muscles / 中国医师杂志

ISE. Conclusion The neuromuscular blocking effects of 4 antibiotics were significantly greater in diaphragm muscle than those in limb muscles.

Changes in the Cutaneous Reflex During Co-contraction of the Antagonist Muscles in the Lower Limb / 体力科学

Task-dependent changes in the cutaneous reflex in the upper and lower leg muscles were examined in normal human subjects (n=11) . After instruction, the subjects were asked to selectively contract agonist muscles (SC task) and to co-contract antagonistic muscles (CC task) for the ankle or knee joint while standing. The cutaneous reflex was elicited by applying non-noxious electrical stimulation to the superficial peroneal nerve at the ankle joint (200 Hz, 5 pulses) . The EMG signal was rectified, averaged (n=10), cumulatively summated up to 150ms after the end of the stimulation artifact, and then divided by the time interval for the summation (ACRE<SUB>150</SUB>) . A strong inhibitory effect was determined at a latency of 50 ms and was followed by a facilitatory effect after the electrical stimulation during the SC task in all muscles. In contrast, it was found that the early inhibition and the later facilitation tended to be decreased and increased during the cc task, respectively. A linear regression analysis between the ACRE<SUB>150</SUB> and the background EMG revealed that the regression slopes were significantly decreased during CC task except for the tibialis anterior (TA) and biceps femoris. The reflex ratio (ACRE<SUB>150</SUB>/background EMG) was also negative for the SC task in all muscles tested, but was significantly reduced or showed a positive value for the CC task. These results suggest that the brain may control the cutaneous reflex pathways to enhance the facilitatory effects of the thigh and ankle extensor muscles during the CC task. This reflex action during the CC task may serve to prevent an undesirable fall in the center of gravity in response to a sudden tactile sensation to the dorsal surface of the foot.