Effects of Lower Rib Expansion Limitation on Maximal Respiratory Pressure and Abdominal Muscle Activity During Maximal Breathing in Healthy Subjects

Purpose@#The aim of this study was to determine the effects of lower rib cage lateral expansion limitation on the maximal inspiratory and expiratory pressures and on abdominal muscle activity during maximal respiratory breathing in healthy subjects. @*Methods@#Fifteen healthy male subjects voluntarily participated in this cross-sectional study. During maximal breathing, maximal inspiratory and expiratory pressures were measured, and abdominal muscle activity was determined with using surface electromyography. Also, the measurement was repeated with using a non-elastic belt to the lower rib cage for limiting of lateral expansion. A Wilcoxon signed-rank test was performed for obtaining the statistical difference with a significance level of 0.05. @*Results@#The findings of this study are as follows: 1) There were no significant differences in maximal inspiratory and expiratory pressure with and without lower rib cage lateral expansion (p>0.05), 2) There was no significant difference in abdominal muscle activity during the maximal inspiratory phase (p>0.05). However, right external oblique muscle activity decreased significantly during maximum exhalation with lower rib expansion limitation (p<0.05). @*Conclusion@#The results of the current study indicate that a non-elastic belt was effective in decreasing right external oblique muscle activity during forced expiratory breathing in healthy subjects.

Effects of Lower Rib Expansion Limitation on Maximal Respiratory Pressure and Abdominal Muscle Activity During Maximal Breathing in Healthy Subjects

Purpose@#The aim of this study was to determine the effects of lower rib cage lateral expansion limitation on the maximal inspiratory and expiratory pressures and on abdominal muscle activity during maximal respiratory breathing in healthy subjects. @*Methods@#Fifteen healthy male subjects voluntarily participated in this cross-sectional study. During maximal breathing, maximal inspiratory and expiratory pressures were measured, and abdominal muscle activity was determined with using surface electromyography. Also, the measurement was repeated with using a non-elastic belt to the lower rib cage for limiting of lateral expansion. A Wilcoxon signed-rank test was performed for obtaining the statistical difference with a significance level of 0.05. @*Results@#The findings of this study are as follows: 1) There were no significant differences in maximal inspiratory and expiratory pressure with and without lower rib cage lateral expansion (p>0.05), 2) There was no significant difference in abdominal muscle activity during the maximal inspiratory phase (p>0.05). However, right external oblique muscle activity decreased significantly during maximum exhalation with lower rib expansion limitation (p<0.05). @*Conclusion@#The results of the current study indicate that a non-elastic belt was effective in decreasing right external oblique muscle activity during forced expiratory breathing in healthy subjects.

Transcutaneous Electrical Nerve Stimulation and Microcurrent Electrical Neuromuscular Stimulation on Pain Behaviors in Rats with an Experimental Neuropathy

OBJECTIVE: The present study was conducted to investigate the effects of transcutaneous electrical nerve stimulation (TENS) and microcurrent electrical neuromuscular stimulation (MENS) on pain-like behaviors developed in rats with an experimental neuropathy. METHOD: Neuropathic surgery was done by a unilateral ligation of L5 and L6 spinal nerves of the rat. Allodynic behavior was examined by measuring foot withdrawal frequency in response to 10 applications of a von Frey filament (2.5 g) to the plantar surface of the foot. Ongoing pain behavior was examined by measuring cumulative time in 3 min that the rat lifted its foot off a plate held at cold temperature (5oC). TENS (square pulses; 3 Hz, 30 mA) or MENS (bipolar pulses; 10 Hz, 300 microampere) was applied for 15 min or 5 min, respectively, to the skin of the affected foot. RESULTS: Behavioral signs of mechanical allodynia and cold-induced ongoing pain had developed after nerve injury. Either TENS or MENS, when applied once, alleviated allodynic behavior, lasting up to 2 hrs. Such an alleviation lasted much longer when TENS or MENS was applied repeatedly (once a day for 6 days); 3 days by TENS and 1 day by MENS. Cold-induced ongoing pain behavior, however, was not affected by the repeated application of either TENS or MENS. CONCLUSION: The results suggest that both TENS and MENS are useful tools for the treatment of mechanical allodynia. Repeated application of TENS or MENS is more effective in alleviating mechanical allodynia than its single application. Either TENS or MENS, however, seems not effective in alleviating cold-induced ongoing pain.

The Changes of Electromyographic Activity of Upper Extremity and Physiologic Cost Index According to Forward and Reverse Wheelchair Propulsion Methods

OBJECTIVE: To compare physiological cost index of the two manual wheel chair propulsion methods: pushing the handrim forward and reversely, and to find out whether the reverse propulsion method will help prevention of the carpal tunnel syndrome in manual wheelchair users. METHOD: The subjects were thirty healthy men in their twenties. All of them performed two manual wheelchair propulsion methods for two days, foreward propulsion on the first day and reverse propulsion the next day. Duration of the wheelchair propulsion was ten minutes. Electromyography (EMG) of wrist extensor groups, biceps brachii, pectoralis major, trapezius, and triceps brachii, and heart rates were recorded. The EMG activity of each individual was transformed to root mean square (RMS), EMG activity appearance time (%), and EMG activity continuance time (%). RESULTS: EMG activity of the wrist extensors in reverse propulsion of the wheelchair was less active compared to forward propulsion. In reverse propulsion method, energy efficiency was not significantly increased, but RMS of wrist extensor groups was significantly reduced. Contractions of trapezius and biceps brachii muscles appeared in earlier phase of propulsion. CONCLUSION: We concluded that reverse propulsion of the wheelchair will be more effective method of wheelchair propulsion compared to forward propulsion in preventing carpal tunnel syndrome in long-term wheelchair users. The reverse propulsion method in this study uses wrist extensor less, which can reduce the wrist extension movement during wheelchair propulsion. It can possibly contribute on the prevention of carpal tunnel syndrome in long-term wheelchair users.