RESUMO
<b>Background:</b> To investigate the effect of high-voltage alternating current (AC) electric field exposure on muscle extensibility. <BR><b>Methods:</b> The study design was a crossover comparison. Fifteen healthy men were randomly divided into two groups. The interventions were exposure and no exposure to a high-voltage AC electric field (18 kV, 30 min). Subjects then performed bilateral self-stretching of the trapezius, hamstrings, and rectus femoris. Skin temperature, blood flow rate, blood pressure, heart rate, muscle rigidity, and muscle extensibility were measured before and after the intervention, and muscle rigidity and muscle extensibility were measured again after stretching. Skin temperature was measured bilaterally on the palms, shoulder girdle, anterior thigh, and dorsum of foot. Blood flow rate was measured in the right radial artery and dorsal artery of the foot. Muscle rigidity was measured bilaterally in the trapezius, rectus femoris, and biceps femoris. Muscle extensibility indices were determined for the left and right angle of lateral neck flexion, heel-buttock distance, straight leg raise angle, and sit-and-reach distance. Skin temperature, blood flow rate, blood pressure, and heart rate were compared between before and after the intervention, and muscle rigidity and muscle extensibility were compared before and after the intervention and after stretching.<BR><b>Results:</b> A significant improvement was found in muscle extensibility in the intervention group but not in the controls. Muscle extensibility improvements due to stretching were noted regardless of electric field exposure, but the degree and percentage of change in muscle extensibility was significantly higher after stretching following electric field exposure. Electric field exposure had no effect on muscle rigidity or circulatory dynamics.<BR><b>Conclusions:</b> Exposure to the high-voltage AC electric field appeared to increase muscle extensibility and heighten the effect of stretching. However, as the mechanism for improved muscle extensibility due to high-voltage AC electric field exposure was not clear, further study is necessary.
RESUMO
Background: To investigate the effect of high-voltage alternating current (AC) electric field exposure on muscle extensibility. Methods: The study design was a crossover comparison. Fifteen healthy men were randomly divided into two groups. The interventions were exposure and no exposure to a high-voltage AC electric field (18 kV, 30 min). Subjects then performed bilateral self-stretching of the trapezius, hamstrings, and rectus femoris. Skin temperature, blood flow rate, blood pressure, heart rate, muscle rigidity, and muscle extensibility were measured before and after the intervention, and muscle rigidity and muscle extensibility were measured again after stretching. Skin temperature was measured bilaterally on the palms, shoulder girdle, anterior thigh, and dorsum of foot. Blood flow rate was measured in the right radial artery and dorsal artery of the foot. Muscle rigidity was measured bilaterally in the trapezius, rectus femoris, and biceps femoris. Muscle extensibility indices were determined for the left and right angle of lateral neck flexion, heel-buttock distance, straight leg raise angle, and sit-and-reach distance. Skin temperature, blood flow rate, blood pressure, and heart rate were compared between before and after the intervention, and muscle rigidity and muscle extensibility were compared before and after the intervention and after stretching. Results: A significant improvement was found in muscle extensibility in the intervention group but not in the controls. Muscle extensibility improvements due to stretching were noted regardless of electric field exposure, but the degree and percentage of change in muscle extensibility was significantly higher after stretching following electric field exposure. Electric field exposure had no effect on muscle rigidity or circulatory dynamics. Conclusions: Exposure to the high-voltage AC electric field appeared to increase muscle extensibility and heighten the effect of stretching. However, as the mechanism for improved muscle extensibility due to high-voltage AC electric field exposure was not clear, further study is necessary.
RESUMO
We report a clinical study conducted to investigate the effects of Electric Field Therapy (EFT) generated by HEALTHTRON on the stiffness in the neck and shoulder area. In Japan, most cases of stiffness in the neck and shoulder area are caused by painfully hypertonic muscles due to various causes such as cervical damage, mechanical stress, disordered cutaneous sensation and psychogenic stress. Internal disorders can also be significant causes of the painful stiffness in the neck and shoulder area. Subjects were 62 outpatients with chief complaints of stiffness in the neck and shoulder area. Informed consent was obtained from each subject. The patients with organic and/or pathological changes in the muscloskeletal system, mental disorder, or internal disease were not included in this study according to the exclusion criteria for feasible focus in hypertonic muscles.<br>The present study consists of two comparisons, 1) standard treatment in our clinic vs. additional HEALTHTRON, by observing the visual analogue scale (VAS) of stiffness in the neck and shoulder area and general condition, lymphocyte percentage in peripheral blood, blood pressure, and 2) HEALTHTRON alone vs. direct-contact electric stimulation (DCES) alone by observing circulatory blood in the trapezium, and the changes of autonomic nervous activity by heart rate variability (HRV). Results of the first research revealed that the stiffness in the neck and shoulder area was improved more quickly by additional HEALTHTRON than by the standard treatment, according to the results of VAS analysis. The general conditions were also improved in the patients treated with the additional HEALTHTRON. The lymphocyte percentage was increased by the addition HEALTHTRON, which suggested that parasympathetic nerve get a predominant position. The average blood pressure in the hypertensive patients in both groups was decreased after the treatment in this investigation, but blood pressure did not change in the patients with hypotension. The second research found that the blood circulation in the trapezium increased in each group treated with HEALTHTRON or DCES; however, the differences between two groups were not statistically significant. No changes in activity of the autonomic regulation were observed in the patients treated with DCES from an analysis of HRV. In contrast, the sympathetic and parasympathetic nervous systems were activated by HEALTHTRON, according to HRV analysis. These results suggest that EFT (HEALTHTRON) are effective for treating stiffness in the neck and shoulder area, and improve the status of the autonomic nervous system.