• Journal of the Korean Applied Science and Technology
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• v.39 no.5
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• pp.596-604
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• 2022

This study aimed to examine the mediating effects of anxiety between adolescents' smartphone overdependence and fatigue recovery, and to secure the evidence data for adolescents' smartphone overdependence intervention. Among the 16th Korea Youth Risk Behavior Survey, 54,948 students were included. Data were analyzed using Pearson correlation coefficients, factor analysis, mediating effect analysis. The results were as follows. Smartphone overdependence had a direct effect on fatigue recovery and an indirect effect on fatigue recovery through anxiety. Smartphone overdependence had a significant effect on anxiety and fatigue recovery. Also, anxiety is verified as the mediation effect between smartphone overdependence and fatigue recovery. When we prepare intervention programs which improve fatigue recovery for adolescents, we need to consider anxiety.

• The Journal of Korean Physical Therapy
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• v.26 no.6
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• pp.425-429
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• 2014

Purpose: The first purpose of this study was to evaluate whether hand muscle fatigue alters sensorimotor control of the hand in healthy subjects, using hand position sense. The second objective was to assess the repositioning variables during a 7.5-min period after the fatigue protocol. Methods: Participants performed a repeated handgrip movement to induce the fatigue condition as fast as possible, until they could no longer continue. Recordings were performed before (pre-fatigue) and after the completion of the fatigue exercises (immediately: post-fatigue, after a 2.5 min recovery, after a 5 min recovery and after a 7.5 min recovery). Results: The joint reposition test of the MP joint in the post-fatigue condition showed higher reposition errors than the prefatigue condition (p<0.05). Additionally, there was a significant difference in recovery of joint reposition errors after fatiguing exercises of the hand muscle, among groups (p<0.05). Conclusion: The fatigue of the hand muscles affected joint position sense by an alteration of somatosensory and proprioceptive information. Nonetheless, the effect of hand muscle fatigue was short-lived, since joint reposition errors decreased to post-fatigue values after 7.5 min of recovery.

• Korean Journal of Acupuncture
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• v.28 no.4
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• pp.59-66
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• 2011

Objectives : This study is aimed to evaluate and objectify the therapeutic effect of moxibustion on muscle fatigue recovery. Methods : To evaluate the therapeutic effect on the muscle fatigue recovery, we compared the fatigue recovery of two groups (non-stimulation group and moxibustion group) by analyzing the EMG and peak torque after strenuous knee exercise of isokinetic contraction. Results : The median frequency (MF) of the moxibustion group was recovered faster than that of the non-stimulation group. However, the peak torques of both groups were not restored until after 20 minutes. Nevertheless, the moxibustion group's peak torque was regained higher than that of the non-stimulation group. Conclusions : We confirmed the therapeutic effect of moxibustion and found that the moxibustion can used as prevention method for musculoskeletal disease.

• Korean Journal of Acupuncture
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• v.29 no.4
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• pp.634-642
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• 2012

Objectives : The aim of the study is to find out whether effect of acupuncture is depending on the diameter of needle, which is a possible component of dose of acupuncture needling. Methods : To compare acupuncture effects in different diameters of needle, we measured the changes in muscle fatigue recovery using surface electromyogram(sEMG) in healthy 8 volunteers. Muscle fatigue was induced by 20 times sit-up for 1 min. Immediately after induction of muscle fatigue, acupuncture needle was inserted into ST36 or ST25 for 10 min by diameters of 0.20 mm, 0.30 mm, or 0.40 mm needles. The sEMG recording was followed by acupuncture for 30 min. As a control group, sEMG was recorded for the same period at rest after muscle fatigue induction. Results : In both of ST 36 and ST 25, stimulation with 0.4 mm diameter needle showed significant rapid recovery followed by short period of muscle fatigue increase. Stimulation with 0.2 mm diameter significantly suppressed the increase of muscle fatigue. Conclusions : These data suggest that acupuncture effect is, at least in part, dependent on diameter of needle. Therefore, diameter of needle is also considered to achieve effective outcome of acupuncture.

• Journal of Life Science
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• v.9 no.1
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• pp.92-98
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• 1999

This study was aimed to evaluate the effect of saengmaeksan on the recovery of exercise induced fatigue. In this experiment, white rats were divided into 2 groups; control group and Saengmaeksan treated group. The results were as follows: 1. Oxygen consumption was significantly decreased in Saengmaeksan treated group than in control. 2. Serum lactate levels were significantly decreased in Saengmaeksan treated group than in control. 3. Serum LDH activities were significantly decreased in Saengmaeksan treated group than in control. 4. Serum triglyceride levels were significantly increased in Saengmaeksan treated group than in control. 5. Serum glucose levels were significantly increased in Saengmaeksan treated group than in control. 6. Serum FFA levels were significantly decreased in Saengmaeksan treated group than in control. According to the results, saengmaeksan showed remakable effects in the recovery of exercise induced fatigue.

• Journal of Life Science
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• v.8 no.4
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• pp.366-366
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• 1998

To investigate the effect of Ssanghwatang and Ssanghwatang-mixed-Paedoksan on the recovery of exercise induced fatigue, we observed content changes of lactate, LDH, glucose, FFA as metabolic substance in the serum of rats administered these drugs just after adn 120 minutes after maximum swimming,. The results were obtained as follows: 1. Lactate was found to be decreased in the rats with administration of Ssanghwatang and Ssanghwatang-Mixed-Paedoksan, 2. serum LDH activity was found to be decreased in the rats with administration of Ssanghwatang-Mixed-Paedoksan, 3. glucose was found to be increased in the rats with adiministation of Ssanghwatang-Mixed-Paedoksan, 4. FFA was found to be decreased in the rats with administation of Ssanghwatang and Ssanghwatang-Mixed-Paedoksan,.

• Journal of Life Science
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• v.8 no.4
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• pp.336-372
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• 1998

To investigate the effect of Ssanghwatang and Ssanghwatang-mixed-Paedoksan on the recovery of exercise induced fatigue, we observed content changes of lactate, LDH, glucose, FFA as metabolic substance in the serum of rats administered these drugs just after adn 120 minutes after maximum swimming,. The results were obtained as follows: 1. Lactate was found to be decreased in the rats with administration of Ssanghwatang and Ssanghwatang-Mixed-Paedoksan, 2. serum LDH activity was found to be decreased in the rats with administration of Ssanghwatang-Mixed-Paedoksan, 3. glucose was found to be increased in the rats with adiministation of Ssanghwatang-Mixed-Paedoksan, 4. FFA was found to be decreased in the rats with administation of Ssanghwatang and Ssanghwatang-Mixed-Paedoksan,.

• Journal of Environmental Science International
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• v.33 no.3
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• pp.217-226
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• 2024

Manufacturing workers face increased fatigue and stress due to environmental factors in workplace such as noise and vibration. Addressing this issue requires creating conducive rest spaces; however, the existing conditions of rest spaces in manufacturing workplace are subpar and lack sufficient scholarly evidence. This study investigated the effect of nature-based rest spaces on the physical and emotional recovery from fatigue on manufacturing workers. Three manufacturing complexes with nature-friendly rest spaces were selected, and 63 manufacturing workers participated in the study. The measurement tools included the Multidimensional Fatigue Scale (MFS) for fatigue levels, physiological indicators (blood pressure and heart rate), and emotional indicators (Zuckerman Inventory of Personal Reaction Scale; ZIPERS, Perceived Restorativeness Scale; PRS, Profile of Mood States; POMS and State-Trait Anxiety Inventory; STAI). The study compared recovery levels during a 7-minute rest between a space without plants and a space with natural elements. The results indicated a significant reduction in systolic and diastolic blood pressure of participants in green rest spaces compared with those in conventional rest spaces. Regarding fatigue levels, green rest spaces showed a decrease in systolic blood pressure in the middle-fatigue and high-fatigue groups. Positive feelings increased in green spaces, whereas negative emotions decreased, suggesting that short breaks in nature-friendly environments effectively promote workers' physical and emotional recovery. Furthermore, this study emphasizes the importance of green space in various work environments to promote well-being in workers.

• Safety and Health at Work
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• v.6 no.3
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• pp.240-248
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• 2015

Background: Recovery from fatigue is important in maintaining night workers' health. This study compared the course of self-reported recovery after 2-week 12-hour schedules consisting of either night shifts or swing shifts (i.e., 7 night shifts followed by 7 day shifts) to such schedules consisting of only day work. Methods: Sixty-one male offshore employees-20 night workers, 16 swing shift workers, and 25 day workers-rated six questions on fatigue (sleep quality, feeling rested, physical and mental fatigue, and energy levels; scale 1-11) for 14 days after an offshore tour. After the two night-work schedules, differences on the $1^{st}$ day (main effects) and differences during the follow-up (interaction effects) were compared to day work with generalized estimating equations analysis. Results: After adjustment for confounders, significant main effects were found for sleep quality for night workers (1.41, 95% confidence interval 1.05-1.89) and swing shift workers (1.42, 95% confidence interval 1.03-1.94) when compared to day workers; their interaction terms were not statistically significant. For the remaining fatigue outcomes, no statistically significant main or interaction effects were found. Conclusion: After 2-week 12-hour night and swing shifts, only the course for sleep quality differed from that of day work. Sleep quality was poorer for night and swing shift workers on the $1^{st}$ day off and remained poorer for the 14-day follow-up. This showed that while working at night had no effect on feeling rested, tiredness, and energy levels, it had a relatively long-lasting effect on sleep quality.

• Journal of the Ergonomics Society of Korea
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• v.27 no.3
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• pp.15-22
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• 2008

The purpose of this study was to define the effects of noise and background music on the trunk muscle fatigue during dynamic lifting and lowering tasks. Six healthy male subjects with no prior history of low back disorders participated in this study. The participants were exposed to two levels of background noise such as 40dB noise and 90dB noise and three levels of background music such as no music, slow music, and fast music. Six different combinations of background noise and background music were played while the participants were performing the lifting task at 15% level of Maximum Voluntary Contraction. Electromyography signals from six muscles were collected and fatigue levels were analyzed quantitatively. In results, the 90dB noise increased trunk muscle fatigue and slowed down the recovery. The trunk muscle fatigue was the lowest when the fast music was played for as background. After recovery, the 90dB noise increased trunk muscle fatigue. The trunk muscle fatigue was the lowest when the slow music was played for as background. The results can be useful to manage the cumulative fatigue of trunk muscles due to background noise and music during repetitive lifting and lowering tasks in industry.