Gait restoration plays a crucial role in improving ADL and QOL following stroke. Pedaling exercise with functional electrical stimulation (FES-pedaling) is one of the conventionally used therapies. Transcranial direct current stimulation (tDCS）was recently suggested to improve motor dysfunction by combining physical training and the therapeutic effects of transcutaneous electrical stimulation. Therefore, we tested the hypothesis that tDCS might enhance the effect of FES-pedaling on improving gait restoration. The inclusion criteria for our single-blind, crossover, within subjects study were first-time stroke, age 18 to 80, no comorbidity, normal cognitive ability (a Mini Mental State Examination score ≥21) and walking 10 m independently. In addition to conventional therapy, patients underwent 2-mA anodal tDCS over the affected primary motor cortex and 10 min of FES-pedaling for 5 consecutive days (tDCS) and only 15 s of the same tDCS at the beginning of the 10-min FES-pedaling (sham) for another 5 days. The 10 m-walking speed, 6-minute walking distance，Timed Up and Go Test (TUG)，Fugl-Meyer Assessment in lower limb, and strength of tibial anterior muscle were measured pre- and post- intervention. Of the 96 stroke patients initially screened, five met the inclusion criteria. In the tDCS condition, the 6-minute walking distance and TUG were significantly improved (171.8±68.7 m to 194.0±75.0 m and 23.0±11.7 s to 20.2±10.9 s, respectively), but only the TUG improved in the sham condition (21.6 ±10.2 s to 18.6±9.0 s). These results suggest that anodal tDCS aid in improving gait restoration, but its mechanism should be clarified for evidence-based clinical practice.

We aimed to study the change in spinal motor neurons excitability during motor imagery under 10% MVC by F-wave, and we studied whether subjects did motor imagery under appropriate muscle contraction strength by comparing the average pinch force between pre- and post-motor imagery. We recorded the F-wave in 9 healthy volunteers (9 males, mean age 20.2 years). In the resting trial, the F-wave was recorded while the muscle was relaxed. We measured 100% MVC by asking the subjects to apply maximum pressure to the pinch meter sensor for 10 s. Subsequently, the subjects learned enough to deliver isometric thenar muscle activity under 10% MVC (target pinch force). As pre-motor imagery motor task, they were then instructed to do learned thenar muscle activity under 10% MVC for 10 s with their eyes closed, and measured the average pinch force. The subjects did motor imagery under 10% MVC for 1 min. The F-wave was recorded during motor imagery. After motor imagery, as post-imagery motor task, the subjects reproduced the thenar muscle activity under imagined muscle contraction strength with their eyes closed, and measured the average pinch force. Persistence and F/M amplitude ratio during motor imagery were significantly increased than those at rest. There were no differences among target pinch force, and two average pinch forces at pre- and post-imagery motor task. Motor imagery under 10% MVC can increase the excitability of spinal motor neurons. We guessed that the subjects could motor imagery of thenar muscle activity under correct 10% MVC.

The effect of Transcutaneous Electrical Nerve Stimulation (TENS) is influenced by electrode placement and psychological factors. The purpose of this study was to compare ipsilateral with bilateral stimulation at the same charge amount and to clarify the influence of anxiety. A randomized cross-over trial design was used in which the 21 healthy volunteers received 3 patterns of electrode placement (R-1channel: right L3/4 dermatome is stimulated by 1 channel, R-2channel: right L3/4 dermatome is stimulated by 2channel, B-2channel: bilateral L3/4 dermatome is stimulated by 2channel). State-trait anxiety inventory Y-2 (STAIY-2) and pressure pain threshold (PPT) were measured. TENS was administered for 30 minutes and PPT on right pes anserinus was measured at baseline and 3 sequent 10-minute intervals. The percentage change of PPT was analyzed using two way repeated measures analysis of variance, and multiple comparison. The relationship percentage change of PPT at 30 minute and STAIY-2 is analyzed using pearson’s product moment correlation coefficient. As a result, the percentage change of PPT at 10, 20 minute significantly increased in B-2channel and R-2channel compared to R-1channel (p＜0.01), and at 30 minute significantly increased in B-2channel compared to R-1channel (p＜0.01) and R-2channel (p＜0.05). The percentage change of PPT in B-2channel was significantly negatively correlated with STAIY-2 (r=−0.44, p＜0.05). These data indicate that bilateral stimulation is greater hypoalgesic effect compared to ipsilateral stimulation and anxiety influences the effect of TENS.

Objective: We investigated the effect of electrical train stimulation on corticospinal excitability. Methods: A total of 24 healthy volunteers participated in two different experiments. In both experiments, short-duration electrical train stimulation (5 s) was delivered to the right median nerve. In experiment 1, the number of electrical pulses within a train of electrical stimulation was set to 2, 4, 6, 8, and 10, and the inter-train interval (ITI) was set to 50 ms. In experiment 2, the number of electrical pulses within a train was set to 4 and 8, and ITI was set to 100 ms. Motor evoked potentiation (MEP) was measured in the abductor pollicis brevis and abductor digiti minimi muscles, before and immediately after electrical train stimulation. Result: Electrical train stimulation using eight repetitive electrical pulses within a train significantly increased the MEP measured in the abductor pollicis brevis but not the abductor digiti minimi. There was no significant difference between MEP change induced by electrical train stimulation with four repetitive electrical pulses and ITI of 50 ms and that induced using eight repetitive electrical pulses and an ITI of 100 ms. Discussion: Both the number of electrical pulses within a train of electrical stimulation and ITI might influence the MEP change induced by electrical train stimulation.

The purpose of the present study was to investigate the effects of neuromuscular electrical stimulation (NMES) on skeletal muscle from a mouse model of cancer cachexia with special focus on the role of glutamine synthetase (GS), a downstream regulator of glucocorticoid signaling. CD2F1 mice were divided into 4 groups: control (CNT), CNT+NMES, C-26, and C-26+NMES. Cancer cachexia was induced by a subcutaneous injection of colon 26 (C-26) cells. The NMES (60% of maximum torque, 50 Hz, 2 s on/4 s off, total of ～30 contractions) was performed to the triceps surae muscles every other day starting one day after injection of C-26. After 28 days of C-26 injection, the weight of gastrocnemius (Gas) and soleus (SOL) muscles and locomotor activity were decreased in C-26 group. These changes were accompanied by a marked increase in the expression of GS. NMES partially prevented the loss of muscle weight in SOL, but not Gas, in C-26 mice. Moreover, the GS expression in Gas muscles from C-26+NMES group was lower than that in C-26 group, but was still higher than CNT group. In contrast, GS expression of SOL in C-26 mice was not affected by NMES. These findings suggest that cancer cachexia-induced muscle atrophy involves different mechanisms depending on fiber types. The fast-twitch muscle atrophy is induced, at least in part, by an activation of glucocorticoid pathway, whereas slow-twitch muscle atrophy is due not only to increased glucocorticoid signaling, but also to disuse. Moreover, NMES may be less effective on muscle atrophy induced by glucocorticoid signaling than that induced by disuse.

The purpose of this study was to evaluate the influence to circulation from pulsed electromagnetic field (PEMF) at different output intensities by using ultrasound imaging to assess blood flow velocity. Subjects consisted of 10 healthy male students who did not have any sensory problems, and no contraindications to ultrasound or PEMF. The PEMF was applied for 60 minutes to the right elbow (brachial artery), with the left elbow at rest acting as the control. Using pulsed Doppler mode, blood flow velocity and skin temperature were measured 5 times at 0, 15, 30, 45, and 60 minutes.　The results showed that regardless of intensity, at 45 and 60 mins of PEMF, there were significant decreases in blood flow velocity between group and within group.　Therefore, our study demonstrated that blood flow velocity decreased after a long period of PEMF application. Based on the equation of continuity, the reason for the decrease in blood flow velocity may be due to vascular dilation. However, the physiological mechanisms of PEMFs on circulation dynamics will require further studies.