• 한국운동역학회지
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• 제26권1호
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• pp.31-37
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• 2016

Purpose: The purpose of this study was to investigate the differences in FT (free-torque) components between non-fatigue and fatigue conditions induced by prolonged running. Methods: Fifteen healthy runners with no previous lower-extremity fractures ($22.0{\pm}2.1$ years of age) participated in this study. Ground reaction force data were collected for the right-stance phase for 10 strides of 5 and 125-min running periods at 1,000 Hz using an instrumented force platform (instrumented dual-belt treadmills, Bertec, USA) while the subjects ran on it. The running speed was set according to the preferences of the subjects, which were determined before the experiment. FT variables were calculated from the components of the moment and force output from the force platform. A repeated-measures one-way ANOVA was used to test for significant differences between the two conditions. The alpha level for all the statistical tests was 0.05. Results: The absolute FT at the peak braking force was significantly greater after 5 mins of running than after 125 mins of running-which was regarded as a fatigued state-but there were no significant differences in the absolute peak FT or impulse between the conditions. Conclusion: The FT variables in the fatigue condition during prolonged running hardly affect the tibial stress syndrome.

• 대한물리의학회지
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• 제14권3호
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• pp.127-133
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• 2019

PURPOSE: The aim of this study was to obtain detailed and quantified data concerning the effects of plantarflexor fatigue induced to the non-paretic side on muscle activities of the bilateral lower extremities during walking in chronic stroke patients. METHODS: In this study, chronic stroke patients were evaluated for six months after the onset of stroke. To induce the non-paretic plantarflexor fatigue, 20 chronic stroke patients were asked to perform their given fatigue affecting assignments, which were presented in a forced contraction fatigue test method, until the range of motion of the plantarflexor was reduced to less than 50%. The muscle activities of the rectus femoris, tibialis anterior and gastrocnemius in the paretic and non-paretic lower extremities were measured using a wireless surface EMG before and after muscle fatigue induction. RESULTS: The findings showed that after plantarflexor fatigue was induced on the non-paretic side, a significant decrease in muscle activities of the rectus femoris on the paretic side was noted (p<.05). The muscle activities of the tibialis anterior and gastrocnemius were also observed to decrease, but, these results were not statistically significant (p>.05). In the non-paretic side, there was a significantly decrease in the muscle activities of the rectus femoris, tibialis anterior, and gastrocnemius (p<.05). CONCLUSION: These finding suggest that the muscle fatigue of the non-paretic plantarflexor affects not only the muscle activity of the ipsilateral lower extremity but also the muscles activity of the contralateral lower extremity. This highlights the necessity of performing exercise or training programs that do not cause muscle fatigue in clinical aspects.

• PNF and Movement
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• 제16권3호
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• pp.355-363
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• 2018

Purpose: The purpose of this study was to obtain detailed and quantified data concerning the effects of plantarflexor muscle fatigue induced in the non-paretic side on the spatial and temporal gait parameters of the bilateral lower extremities during walking in stroke patients. Methods: This study was conducted on 20 patients with chronic stroke. The load contraction fatigue test was applied to induce muscle fatigue in the non-paretic plantarflexor muscle. Step length, stride length, double support, gait velocity and cadence, and functional ambulatory profile (FAP) score in the bilateral lower extremities were measured using a gait analysis system in order to investigate changes in temporal and spatial gait parameters caused by muscle fatigue on the non-paretic side. The statistical significance of the results was evaluated using a paired t-test. Results: A review of the results for gait parameters revealed a significant increase in double support (p<0.05) and a significant decrease in step length, stride length, gait velocity and cadence, and FAP score (p<0.05). Conclusion: These results indicate that the muscle fatigue in the non-paretic side of the stroke patients also affected the paretic side, which led to a decrease in gait functions. This implies a necessity to perform exercise or training programs in a range of clinical aspects not causing muscle fatigue.

• 국제물리치료학회지
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• 제11권3호
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• pp.2147-2154
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• 2020

Background: Improperly conducted exercise may lead to worsening of musculoskeletal complications. Such may worsen due to increased repetition and intensity during exercise. In addition, different responses may show different needs for training program. Objectives: To compare kinematics of symmetric concentric and eccentric motions during increased repetitions and intensities for men and women. Design: Quasi-randomized trial. Methods: A total of ten men and eleven women participated in this study. Concentric and eccentric motions of the lateral raises were observed for initial positions of abduction and adduction. Low and high exercise intensities were applied, and 15 repetitions were conducted for both intensities. Initial, 3 inbetween repetitions, and last repetition were recorded for comparisons. Results: The concentric or abduction motions showed no significant differences for all comparisons. However, eccentric or adduction motions showed greater significant differences as the exercise intensity increased for both men and women. Such significant differences were most prevalent during the first and last repetitions with greatest differences during the initial repetitions. Conclusion: Kinematic difference between men and women during increased repetitions and intensity indicate the need for more individualized exercise intervention and consideration between men and women. Individualized interventions may prevent exercise-induced postural abnormality and corresponding musculoskeletal dysfunction.

• 대한한방내과학회지
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• 제30권1호
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• pp.94-106
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• 2009

Objectives : This study aimed to evaluate the effect of Wongisaengmaek-san (extracted with water or 50% ethanol) on antioxidative activity and recovery of fatigue induced by weight-loaded forced swimming exercise. Methods : Antioxidant activity of Wongisaengmaek-san was evaluated in terms of total amount of polyphenol, 1.1-diphenyl-2-picrylhvdroxyl (DPPH) radical scavenging activity and xanthine oxidase inhibition. The anti-fatigue effect of Wongisaengmaek-san was investigated using an acute weight-loaded forced swimming test by monitoring swimming test times and blood biochemical parameters creatinine. BUN, lactic acid dehydrogenase (LDH), free fatty acid (FFA) and lactic acid (LA). Results : 1. 50% EE (ethanol extract) had 2.3 times higher amount of total polyphenol compared to water extract. 2. It was identified that 50% ethanol extract showed enhancement of xanthine oxidase inhibition and DPPH scavenging effect in vitro. 3. According to anti-fatigue effect in the scale of 5% weight loaded mouse swimming test, both water and 50% ethanol extract showed significant improvement of swimming time elongation respectively, and 50% ethanol extract induced a more positive result. 4. After swimming for 1% weight-loaded mouse. water extract and 50% ethanol showed significant anti-fatigue effect with manifestation of blood sampling among both of the intervention: 50% ethanol extract showed a greater result. Conclusions : 50% ethanol extract of Wongisaengmaek-san has more effective antioxidant activity and anti-fatigue than water extract.

• 대한약침학회지
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• 제22권2호
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• pp.68-74
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• 2019

Objectives: Cultivated wild ginseng (cWG), called SanYangSanSam, has been used clinically in patients with chronic fatigue in Korea. Little is known about effects of the ginseng distilled (volatile) components produced during evaporizaiton. Recently, we first identified one major component from cWG distilled extract, panaxydol, by using mass spectrometry. However, functional properties of cWG distilled extract and panaxydol remains elusive. Therefore, the present study evaluated the effect of cWG distilled extract or panaxydol on exercise-induced fatigue in rats. Methods: Fatigue was induced by forced swimming and the immobility time was analyzed in male Sprague-Dawley rats. The animals received intraperitoneally either vehicle, cWG distilled extract, or panaxydol 10 min prior to beginning of the forced swimming test (FST) once daily for 5 days. After the FST on day 5, we also analyzed fatigue-related biochemical levels including blood urea nitrogen (BUN), lactate acid (LAC), and lactate dehydrogenase (LDH) in serum and levels of glycogen in liver and soleus muscle. Results: The forced swimming time in cWG distilled extract (0.6 mL/kg)-treated group was significantly longer than that of control group on day 4 and 5. Panaxydol (0.1 and 0.25 mg/kg)-treated groups showed significantly enhanced performance in the forced swimming, compared to control. In addition, a significant decrease in serum LDH level was found in panaxydol-treated group, while there were no alternations in levels of serum BUN and LAC and glycogen in liver or soleus muscle. Conclusion: The present study demonstrated cWG distilled extract and its active component panaxydol have a function of anti-fatigue.

• The Journal of Korean Physical Therapy
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• 제18권1호
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• pp.1-10
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• 2006

Purpose: This study was to investigate how induced microcurrent shoes affect relief of feet pain, which often occurs to persons who are more than fifty years old and how they prevent fatigue of feet generated during everyday life. The subjects of this study were comprised af five males and five females, who agreed with this research and ate more than fifty years old. And they all have plantar faciitis and pain in their feet. Methods: Subjects ware the induced microcurrent shoes far more than 4 hours everyday during the test. When they wore those shoes, they also wore the specially produced shacks made of silver-mixed thread and they were asked to avoid serious exercise. Prior to starting test and after the test, assessments were carried out two times. In the examination before the test, general shoes were used and in examination after the test, induced microcurrent shoes used. Muscle fatigue was measured by electromyography(MP150, Biopac, USA). When the walking rate of subjects on a treadmill was increased from 2.Km/h to 3Km/h for 10 minutes, muscle activities of a lower leg were measured during the whale walking process by MP150 remote monitoring system(TEL 100C). And pain was measured by VAS. Results: The results are as follows. 1. Comparisons of VAS before and after experimentation showed that degree of pain was significantly decreased(p < .05). 2. Degree of fatigue of Tibialis anterior was significantly decreased after 6 weeks of treatment(p < .05). 3. Degree of fatigue of Soleus was slightly decreased after 6 weeks of treatment, but did not show significant difference (p > .05). Conclusion: The above results suggest that induced microcurrent shoes is helpful decreasing fatigue of feet and relief of feet pain.

• 대한통합의학회지
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• 제8권2호
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• pp.139-147
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• 2020

Purpose : Proprioceptive position sense plays a key role in providing joint stability, and multiple factors are related to proprioceptive position sense. Thus, this study aimed to determine the effects of body composition, particularly skeletal muscle mass on proprioceptive position sense following muscle fatigue. Methods : Healthy female subjects agreed to have their body composition analyzed. Only subjects who had 18.5-22.9 kg/㎡ of BMI (body mass index) were included in this study, and the participants were divided into two groups by skeletal muscle mass level. The experimental group had a level of skeletal muscle lower than the standard level (n=9), while the control group showed a standard or high level of skeletal muscle mass (n=11). To determine the change in proprioceptive position sense of the knee joint, the absolute angle error (AAE) was evaluated following muscle fatigue on low extremity. The muscle fatigue was induced by isokinetic resistance exercise program of Biodex system. AAE was measured by the Biodex system and compared the result before and after muscle fatigue. Results : The experimental group showed a significant AAE difference between before (3.16±2.48 °) and after (5.40±2.61 °) muscle fatigue. In addition, there was a AAE difference between the experimental (5.40±2.61 °) and control groups (3.53±1.67 °) after fatigue; however, there was no significance. Those results indicated that low level of skeletal muscle mass might influence the proprioceptive position sense of the knee joint after muscle fatigue. Conclusion : Thus, maintaining the proper level of skeletal muscle mass is pivotal to reduce the risk of injury following muscle fatigue in ADL or sport activities.

• 운동영양학회지
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• 제24권4호
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• pp.15-23
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• 2020

[Purpose] Lactate is a principal energy substrate for the brain during exercise. A single bout of high-intensity interval exercise (HIIE) can increase the blood lactate level, brain lactate uptake, and executive function (EF). However, repeated HIIE can attenuate exercise-induced increases in lactate level and EF. The lactate levels in the brain and blood are reported to be correlated with exercise-enhanced EF. However, research is yet to explain the cause-and-effect relationship between lactate and EF. This study examined whether lactate consumption improves the attenuated exercise-enhanced EF caused by repeated HIIE. [Methods] Eleven healthy men performed two sets of HIIE, and after each set, 30 min were given for rest and examination. In the 2^nd set, the subjects consumed experimental beverages containing (n = 6) and not containing (n = 5) lactate. Blood, cardiovascular, and psychological variables were measured, and EF was evaluated by the computerized color-word Stroop test. [Results] The lactate group had a higher EF (P < 0.05) and tended to have a higher blood lactate level (P = 0.082) than the control group in the 2^nd set of HIIE. Moreover, blood lactate concentration was correlated with the interference score (i.e., reverse score of EF) (r = -0.394; P < 0.05). [Conclusion] Our results suggest that the attenuated exercise-enhanced EF after repeated HIIE can be improved through lactate consumption. However, the role of lactate needs to be elucidated in future studies, as it can be used for improving athletes' performance and also in cognitive decline-related clinical studies.

• 대한한의학회지
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• 제26권4호
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• pp.62-73
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• 2005

Objectives: This study was designed to identify the ergogenic effects of Red ginseng and Paeonia radix mixtures and optimal ratios. Materials and Methods: This study was conducted by administering treatments of Red ginseng and Paeonia radix mixtures to rats and by measuring the time to exhaustion by treadmill running. Results: The treatment of Red ginseng and Paeonia radix mixtures to the rats increased the time to exhaustion by treadmill running. The most potent inhibition of Red ginseng and Paeonia radix mixtures on the 5-HT synthesis and the TPH expression in the dorsal raphe was observed at the dose of 200 mg/kg and the optimal ratio of Red ginseng and Paeonia radix for the maximum efficacy was 50:50. Under normal conditions (not exercise), long-term treatment of Red ginseng and Paeonia radix mixtures did not affect the 5-HT synthesis and the TPH expression in the dorsal raphe, suggesting that Red ginseng and Paeonia radix mixtures does not alter serotonin level in the normal rats. The suppressive effect of Red ginseng and Paeonia radix mixtures on the 5-HT synthesis and the TPH expression during exercise is a possible ergogenic mechanism of these mixtures. Conclusions : Red ginseng and Paeonia radix mixtures reduce exercise-induced fatigue, and have the effect of acting as ergogenic aids on the time to exhaustion by treadmill exercise and on 5-HT synthesis and TPH expression.