Objectives: The purpose of this study was to compare vitamin D levels, sleep quality, and anxiety symptoms between shift workers and daytime workers and analyze the mediating effect of vitamin D and sleep quality between shift work and anxiety symptoms.
Methods: The subjects of the study were 6744 people who received a medical examination while working for an electronics manufacturing company in 2016. We evaluated their shift work, vitamin D levels, sleep quality, and anxiety symptoms with blood samples and questionnaires. Chi-square test, t-test and path statistical analysis were performed.
Results: The shift workers had significantly higher symptoms of anxiety than the day workers, significantly lower levels of vitamin D in the blood, and significantly poorer quality of sleep. The results of the pathway analysis confirmed that blood vitamin D and sleep quality had a mediating effect between shift work and anxiety symptoms.
Conclusions: Shift workers should be constantly paying attention to mental health effects such as anxiety symptoms. Shift workers should also be alerted of the risk of vitamin D deficiency, encouraged about sun exposure and vitamin D intake, and required to undergo training and counseling on sleep hygiene.

Purpose: The purpose of this study was to compare the change in pain, Neck Disability Index score, and the craniovertebral angle by performing scapular correction exercise or general neck exercise for five weeks in participants with mechanical neck pain.
Methods: A total of 31 participants were randomly assigned between the scapular correction exercise and the general neck exercise groups, and all participants performed intervention for 40 minutes each, three times a week for five weeks The effects were evaluated by measuring the Visual Analog Scale score, the Neck Disability Index score, and the craniovertebral angle, before and after the intervention. Independent t-tests were used to compare differences between two groups, and to compare differences between pre- and post-intervention, paired t-tests were used.
Results: As measured before and after the intervention, the scapular correction exercise group showed significant improvement in all variables (p<0.05), while the general neck exercise group improved only in the neck disability index score. The differences between the two groups revealed further improvement in the scapular correction exercise group compared to the general neck exercise group (p<0.05).
Conclusion: We found that five weeks of the scapular correction exercise to modify the position and movements of the scapula is clinically an important treatment tool for recovery from chronic mechanical neck pain symptoms and restoration of proper neck function.

Purpose: The purpose of this study was to evaluate the forced vital capacity and sway area of respiratory muscles taping with threshold inspiratory muscles training for 1 week.
Methods: Nineteen stroke patients were divided into two groups: experimental group (respiratory muscles taping with threshold inspiratory muscles training, n=10) and control group (threshold inspiratory muscles training, n=9). Forced vital capacity tests were performed using a spirometer. The instrument records the forced vital capacity (FVC). COP excursion test was performed using Zebris. The instrument records the sway area. All tests were measured before and after intervention.
Results: The experimental group and control group showed significant increase in FVC (p<0.05). The sway area showed a significant decrease only in the experimental group (p<0.05). The FVC and sway area was no significant difference between the two groups (p>0.05).
Conclusion: Threshold inspiratory muscles training is an effective intervention for improving FVC. Threshold inspiratory muscles training with respiratory taping is an effective intervention for improving FVC and sway area. Threshold inspiratory muscles training with respiratory taping can improve balance ability.

Purpose: This study examined the research trends using G-power centered on major Korean registered sites and presents the research trends of studies with a high level of evidence. Method: This study selected three research journals listed in the Korea Research Foundation among physical therapy journals in the field of physiotherapy. The selected papers were classified according to the following: 1) study type, 2) study level, and 3) quality of the study. Result: Sixty-nine articles were selected and classified according to the study type. The musculoskeletal system, central nervous system, and others comprised 73.91% (n=51), 17.39% (n=12), and 8.7% (n=6), respectively. The results were classified into 62 experimental studies, four observational analytic studies, and three descriptive studies. The experimental studies included 22 randomized controlled trials (level 2) and 40 non-randomized trials (level 3). Sixteen randomized controlled trials were classified for a qualitative evaluation, and 12 papers with a score of six or more (good) were found.
Conclusion: Many high-level studies were found in G-power, and the quality of the study was also good. Therefore, the effective number of samples obtained using G-power is one of the ways to enable high-quality research.

Purpose: The talk test (TT) is an alternative, self-reported method for prescribing and guiding exercise training in both healthy adults and patients with cardiovascular and pulmonary diseases. This study examined whether the TT is a valid tool for evaluating the exercise intensity during two different types of aerobic activity on a treadmill or stationary bicycle in a healthy population.
Methods: A total of ten subjects (six males and four females) who had no medical history related to musculoskeletal, cardiovascular, and pulmonary disorders were enrolled in this study. They were evaluated using the TT, which consisted of three-level of difficulties demanding cardiac loads while performing aerobic activities on a treadmill and bicycle ergometer across two consecutive days in a counterbalanced manner. During the activities, the psychophysiological response markers were collected in terms of the heart rate, oxygen saturation, rating of perceived exertion, and metabolic equivalents.
Results: Statistical analyses revealed a significant difference in the between-subject variance regarding the TT level effect (p<0.05). On the other hand, no significant findings were detected on the between-group variance (p>0.05) and the TT level×group interaction (p>0.05). The independent t-test indicated no significant differences in heart rate, oxygen saturation, rating of perceived exertion, and metabolic equivalents at any levels of the TT in the two groups. The TT showed a strong correlation with the rating of perceived exertion.
Conclusion: This study showed that the TT is a valid and alternative tool for evaluating the aerobic exercise intensity in a healthy population. In addition, differences in the psychophysiological response markers between two aerobic activities, treadmill and bicycle ergometer, were detected in the same exercise intensity scaled with the TT. The TT can be used to evaluate and prescribe the exercise intensity of aerobic activity in cardiovascular and pulmonary physical therapy.

Purpose: This study compared the walking ability of chronic stroke patients following either treadmill training with knowledge of the result (KR group) or treadmill training with knowledge of the performance (KP group).
Methods: Nineteen patients with chronic stroke were recruited from a rehabilitation hospital. The patients were divided into two groups: a KR group (10 patients) and a KP group (9 patients). They received 30 minutes of neuro-developmental therapy and treadmill training 30 minutes, five times a week for three weeks. The gait parameters were measured before and after training using the Optogait system.
Results: After the training periods, the KR group showed significant improvement in gait speed, cadence, step length of the unaffected limb, stance time of the affected limb, and functional gait assessment compared to the KP group (p<0.05).
Conclusion: The results showed that treadmill training with KR was more effective in improving the gait speed and cadence, step length of the unaffected limb, stance time of the affected limb, and functional gait ability than the treadmill training with KP. Therefore, to improve the walking ability of stroke patients, it is necessary to consider treadmill training with KR. If it can be combined with conventional neurological physiotherapy, it would be an effective rehabilitation for stroke patients.

Purpose: This study examined the effects of the abdominal hollowing technique applied during plank exercises at different shoulder angles between the ground and the humerus on the abdominal muscle activity
Methods: The subjects were 36 male volunteers. They were randomized to perform plank exercises or plank exercises using the hollowing technique at 80˚, 90˚, 100˚, and 110˚ between the ground and the humerus. The abdominis muscles were measured using a surface electromyogram. Independent t-tests examined the changes in the activity of these muscles according to the two exercise methods at each angle. The changes in muscle activity were examined according to the selected angles by one-way analysis of variance.
Results: The activity of abdominal muscles was investigated according to the angle between the ground and the humerus during the plank exercise. As a result, the muscle activity increased significantly with decreasing angle in the rectus abdominis, external oblique, and internal oblique·transverse abdominis muscles (p<0.05). In terms of the changes in abdominal muscle activity after hollowing plank exercises at the given angles between the ground and the humerus, an increase in angle resulted in a statistically significant increase in the rectus abdominis muscle activity (p<0.05). The activities of the rectus abdominis, external oblique, and internal oblique/transverse abdominis muscles after hollowing plank exercises showed statistically significant increases (p<0.05) compared to those after plank exercises.
Conclusion: The hollowing technique and the increase in the angle between the ground and the humerus may be an effective exercise method for increasing the muscle activity of the abdominis muscles.

Purpose: This study examined the inter-rater reliability of cervical proprioception, dynamic balance ability, and ankle dorsiflexion range of motion using STARmat®, which is a practical clinical tool that can provide practitioners and patients with quantitative and qualitative results.
Methods: Thirty healthy young subjects were enrolled in this study, and two well-trained physical therapists participated as a tester. Two testers measured the cervical joint position error at the starting position after neck flexion, extension, side bending, and rotation; three dynamic balance tests, including anterior excursion, anterior reaching with single leg balance, and posterior diagonal excursion; and ankle dorsiflexion range of motion using STARmat®. The intra-class correlation coefficient (ICC) was used to determine the inter-rater reliability of the tests.
Results: The inter-rater reliability for the cervical proprioception ranged from moderate to good (0.66 to 0.83), particularly for flexion (0.82), extension (0.70), right side bending (0.73), left side bending (0.71), right rotation (0.83), and left rotation (0.66). For the dynamic balance, the inter-rater reliability ranged from good to excellent (0.87 to 0.91), particularly for anterior excursion (0.86), posterior diagonal excursion (0.87 to 0.89), and anterior reaching with a single leg balance (0.90 to 0.91). In addition, for the ankle dorsiflexion range of motion, the ICC for the inter-rater reliability ranged from 0.95 to 0.96.
Conclusion: STARmat® is a reliable tool for measuring cervical proprioception, dynamic balance tests, and ankle dorsiflexion range of motion in healthy young adults.

Purpose: Some patients who have undergone surgery due to lumbar disc herniation still complain of leg pain and other abnormal sensations. Therefore, the study examined the effects of the neurodynamics on pain and other abnormal nerve sensations in post-operated patients with lumbar disc herniation.
Methods: The participants of this study comprised 20 adults (10 males and 10 females) who were diagnosed with lumbar disc herniation. The subjects were classified into two groups of 10 patients each in the lower extremity neurodynamics (LEN) and lumbar stabilization exercise (LSE) groups. Each intervention was applied twice a day for one week and was composed of two different exercise patterns; one was applied by a therapist, and the other was performed by the patients themselves. The data were analyzed using assessment methods of Digital Infrared Thermal Imaging (DITI), Toronto clinical neuropathy scoring system (TCNSS), Sympathetic Skin Response (SSR) test, and Oswestry Disability Index (ODI) scale.
Results: Significant differences in TCNSS, DITI, ODI scale were observed between the LEN and LSE group (p<0.01). On the other hand, there was no significant difference in the SSR test between pre and post-treatment (p>0.05).
Conclusion: The results indicated that neurodynamics treatment is effective in pain reduction and abnormal sensations, such as leg muscle cramps, in post-operated patients with lumbar disc herniation.

Purpose: This study examined the effects of the directions of neck rotation on the muscle activity of the upper trapezius and lower trapezius while rotating a shoulder externally.
Methods: Twenty-five healthy males participated in this study. The subjects were asked to rotate their shoulder externally with 90° shoulder abduction and 90° elbow flexion in three different neck rotations (neutral, ipsilateral, and contralateral) in the prone position. The muscle activities of the upper and lower trapezius were measured using surface electromyography. One way repeated measures ANOVA was used to compare the muscle activity of the upper and lower trapezius depending on the different neck turning directions.
Results: In the upper trapezius, turning the neck in the ipsilateral direction while turning a shoulder externally decreased the muscle activity significantly, but the muscle activity was increased significantly by turning the neck in the contralateral direction. On the other hand, in the lower trapezius, turning the neck in the ipsilateral direction increased the muscle activity significantly, but the muscle activity was decreased significantly by turning the neck in the contralateral direction decreased it significantly.
Conclusion: When someone has an imbalance of shoulder function, turning the neck in the ipsilateral direction while turning the shoulder externally in the prone position is effective in decreasing the activity of the upper trapezius and increasing the activity of the lower trapezius. Therefore, these results could be used as basic evidence for researching patients with shoulder problems.