Background: Falls are a leading cause of injury among older adults, with rural elderly populations in Gyeongsangnam-do, South Korea, experiencing particularly high fall rates (8.4%). Shoulder dysfunction is prevalent among rural older adults and may contribute to impaired balance and increased fall risk. Community-based interventions targeting shoulder function represent a potential strategy for fall prevention in underserved rural areas. Objectives: This study investigated the impact of targeted shoulder-focused physical therapy on enhancing upper-limb function and postural stability among community-dwelling older adults in rural regions. Design: A pre-post intervention study. Methods: Forty-four older adults aged 65 years and above from five rural communities in Gyeongsangnam-do, South Korea, participated in this study. Assessments were performed before and after two intervention sessions spaced two weeks apart. Shoulder function was assessed using the Apley's scratch test and TheraBand resistance for abduction and flexion strength. Balance was measured using the BT-4 Balance Trainer for static and dynamic stability, and functional mobility was examined through sit-to-stand and timed up-and-go tests. The intervention included 20 minutes of individualized physical therapy by an experienced therapist and 20 minutes of personalized exercise guidance by trained student researchers. Results: Shoulder range of motion and muscle strength in both abduction and flexion showed significant improvement (P<.05). Static balance (C90 area with eyes closed) and dynamic balance in forward and lateral directions demonstrated significant enhancement (P<.05). No significant changes were observed in functional mobility tests. Conclusion: Shoulder-specific physical therapy programs can effectively improve upper-limb function and balance control, thereby reducing fall risk among rural older adults as a practical community-based fall prevention strategy.

Background: Weakness of the abdominal muscles reduces trunk control and impairs respiratory function in stroke patients. To strengthen the abdominal muscles, threshold expiratory muscle training and trunk FES can be used. Objectives: This study aimed to investigate whether a combined intervention of threshold expiratory muscle training and trunk FES is more effective in improving trunk control and respiratory function than threshold expiratory muscle training alone. Design: Randomized controlled trial. Methods: Thirty individuals with stroke were randomly assigned to either the experimental group (n=15) or the control group (n=15). The experimental group received threshold expiratory muscle training with trunk electrical stimulation, while the control group performed threshold expiratory muscle training only. Both groups underwent training three times per week for four weeks. Trunk control and respiratory function were assessed pre and post the intervention. Results: Both groups showed significant post-intervention improvement in respiratory function; however, the experimental group demonstrated a greater change than the control group. The control group showed significant improvement only in the total TIS score, whereas the experimental group showed significant improvement across all TIS subcomponents. Conclusion: Combining threshold expiratory muscle training with trunk FES is an effective approach for enhancing not only respiratory function but also trunk control. Synchronizing electrical stimulation with expiratory timing may increase efficiency and strengthen functional muscle contraction, suggesting meaningful clinical value.

Background: Preparatory workforce often lacks pre-employment physical capacity assessments, leading to early occupational injuries. Trunk muscle endurance imbalances may affect lower-limb biomechanics through the kinetic chain. Objectives: To investigate the associations between trunk muscle endurance and static and dynamic balance abilities in the preparatory workforce (firstyear university students preparing to enter industrial workplaces) using sensor- based plantar pressure analysis. Design: Cross-sectional correlational study. Methods: Twenty-two first-year university students participated. Trunk muscle endurance was assessed using McGill trunk endurance tests, static balance was evaluated with the Romberg test using a sensor platform, and dynamic balance was analyzed through plantar pressure assessment during gait. Spearman's rank correlation analysis was performed. Results: The trunk lateral endurance ratios (right/extension and left/extension) demonstrated strong correlations with mediolateral plantar load distribution during gait (r=.616-.711, P<.05). Trunk flexion/extension ratio showed significant correlations with contralateral foot load distribution (r=±.557, P<.01). Correlations with dynamic plantar pressure variables ranged from r=.505 to .711 (moderate to strong), which were numerically stronger than correlations with static balance variables (r=.441-.442, moderate). Conclusion: Lateral trunk muscle endurance is essential for maintaining postural stability and may serve as a preliminary screening tool for the preparatory workforce during the pre-employment transition period. Dynamic gait analysis provides objective data for evaluating balance capacity in young adults transitioning to industrial employment. However, generalizability is limited by the small sample size and single-institution design.

Background: Plank exercises are widely used for core stabilization, but the effects of applying instability to different support surfaces on trunk muscle activation remain unclear. Objectives: This study aimed to investigate the effect of support surface instability on the electromyographic activity of trunk muscles including the rectus abdominis, internal oblique and transversus abdominis, multifidus, and longissimus during the plank exercise. Design: This study is quasi-experimental design. Methods: Thirty healthy university students performed plank exercises under four conditions: stable surface, unstable elbows, unstable feet, and unstable both. Muscle activity was measured using wireless EMG. Data were analyzed using one-way repeated measures ANOVA and Scheffé post hoc tests. Results: The rectus abdominis showed a statistically significant increase in muscle activation when both elbows and feet were placed on an unstable surface compared with the stable condition (P<.05). Conclusions: Unstable support surfaces during planks significantly enhance rectus abdominis activation, increasing global muscle recruitment for postural control. Conversely, stable surfaces may be preferable for training deep stabilizers without excessive superficial muscle dominance.

Background: Despite various treatment methods, many functional ankle instability (FAI) patients continue to experience functional deficits. Objectives: To investigate the effect of additional auditory feedback on balance and ankle function in task-oriented balance training for FAI patients. Design: Randomized controlled trial design. Methods: Forty FAI patients were randomly assigned to the auditory feedback task-oriented balance training (ATBT) group (n=20) and the task-oriented balance training (TBT) group (n=20). The training program was implemented for 4 weeks, 3 days a week. Results: After training, the COG movement area, speed, and distance significantly decreased in both the ATBT and TBT groups (P<.05). Additionally, the COG movement speed and distance in the ATBT group were significantly decreased compared to the TBT group (P<.05). The 6-meter crossover hop test time decreased in both the ATBT and TBT groups (P<.05). The ATBT group exhibited a significantly decreased 6-meter crossover hop test time compared to the TBT group (P<.05). Conclusion: Both ATBT and TBT enhanced balance and ankle function in FAI patients. ATBT was more effective in improving balance and ankle function than TBT.

Background: Turtleneck posture has become increasingly common due to prolonged computer and smartphone use. Walking exercise has been reported to improve postural alignment; however, the effects of inclined backward treadmill walking on turtleneck posture remain unclear. Objectives: To determine whether backward treadmill walking with incline produces greater improvements in turtleneck posture compared with flat backward treadmill walking. Design: A randomized controlled trial. Methods: Thirty university students (20–29 years) with FHP were randomly assigned to two groups: inclined backward treadmill walking (n=20) and flat backward treadmill walking (n=20). Both groups performed 15 minutes of exercise, three times per week for 6 weeks. Outcome measures included Neck Disability Index (NDI), Craniovertebral Angle (CVA), and Cervical Apex (CA). Data were analyzed using paired t-tests and independent t-tests with α=.05. Results: Significant within-group improvements in NDI were observed in the incline group (P<.05), but not in the flat group. Both groups showed significant improvements in CVA (P<.05). Between-group comparisons revealed no statistically significant differences. Conclusion: Backward treadmill walking improved turtleneck posture regardless of incline, with inclined walking yielding greater within-group improvement in NDI. Further studies with larger sample sizes and longer intervention durations are warranted.

Background: Palpation tenderness is a clinically relevant indicator of musculoskeletal pain, yet differences in immediate analgesic response among commonly used physiotherapeutic modalities remain unclear in real-world clinical settings. Objectives: To compare the immediate changes in pressure pain threshold (PPT) among patients who received extracorporeal shockwave therapy (ESWT), interferential current therapy (ICT), or magnetotherapy (MT) as part of routine physical therapy care. Design: Retrospective clinical data analysis using a pre–post intervention comparison. Methods: A total of 105 patient records were retrospectively reviewed. Cases were categorized into ESWT, ICT, or MT based on the device modality documented in the electronic medical records (EMR). PPT was assessed immediately before and after treatment. Within-category changes were analyzed using paired t-tests. Because changes in PPT scores violated normality assumptions, between-category comparisons were performed using the Kruskal–Wallis test with Dunn–Bonferroni post-hoc procedures. Results: ESWT produced the greatest immediate improvement in pressure pain (d<1.2, P<.001), demonstrating significantly larger reductions compared with ICT (d<.8, P<.01) and MT(d<.2, P>.05). Changes in PPT after ICT and MT did not differ significantly (P>.05). Conclusion: ESWT produced the greatest immediate reduction in palpation tenderness, outperforming both ICT and MT. ICT demonstrated moderate improvement, whereas MT showed minimal change. These findings suggest that ESWT may be the most effective modality for rapid short-term pain modulation in musculoskeletal clinical practice.

Background: Pressure biofeedback may facilitate selective rotator cuff activation during shoulder external rotation, but training effects and structural changes are unclear. Objectives: To examine the effects of a 4-week external rotation program with pressure biofeedback on shoulder muscle activity and rotator cuff thickness. Design: Quasi-experimental design. Methods: Thirty healthy adults were randomized to experimental (n=15) or control (n=15). Both performed seated external rotation at 30° with an elastic band (3×12 reps, 4 sessions/week, 4-week); the biofeedback group maintained 40 mmHg scapular adduction pressure. Surface EMG (%MVIC) and ultrasound muscle thickness were assessed pre/post. Paired and independent t-tests were used (α=.05). Results: In the experimental group, teres minor and infraspinatus activity increased, whereas middle and posterior deltoid activity decreased (P<.05). Post-intervention, rotator cuff activity was higher and posterior deltoid activity was lower versus control (P<.05). Muscle thickness showed no significant changes. Conclusions: A 4-week pressure biofeedback training program changed muscle activation during shoulder external rotation by increasing rotator cuff activation and decreasing compensatory deltoid activity. These findings indicate meaningful neuromuscular adaptations during the external rotation task.

Background: Emotional labor, the management of feelings to create organizationally desired emotional displays, has been consistently associated with adverse health outcomes in Western populations. However, cultural context may fundamentally alter these relationships in Asian service economies. Objectives: To examine temporal trends in emotional labor prevalence and investigate associations between emotional labor and health outcomes among Korean service workers over a 17-year period. Design: Repeated cross-sectional study. Methods: We analyzed data from seven waves of the Korean Working Conditions Survey (2006-2023), comprising 271,039 observations. Emotional labor was assessed using validated items measuring frequency of hiding feelings and managing customer emotions. Health outcomes included psychological symptoms (depression, anxiety, fatigue) and physical symptoms (musculoskeletal disorders, headaches, gastrointestinal problems). We employed multivariable logistic regression, fixed-effects models, and mediation analyses, adjusting for sociodemographic and occupational factors. Results: Emotional labor exposure remained stable at approximately 3.0 (5- point scale) from 2014-2023. Health problem prevalence was consistently around 60% across all survey years. Contrary to hypotheses, emotional labor showed no significant association with health problems (OR=0.999, 95% CI: 0.993-1.005, P=0.735). These null findings persisted in fixed-effects analyses (β=-0.0003, P=0.736), gender-stratified models, and interaction tests. The Cochran-Armitage trend test revealed no temporal trends (P=0.865). Mediation analysis found no indirect effects through psychological hazards. Notably, this finding represents a paradoxical discovery that challenges Western-centric assumptions about the universality of emotional labor's health effects. Conclusion: Despite high statistical power and comprehensive methodology, we found no evidence linking emotional labor to health problems in Korean workers. These unexpected findings challenge the assumed universality of emotional labor's health effects and suggest cultural factors may fundamentally modify occupational stress pathways. Western-derived theoretical models may require substantial adaptation for Asian contexts where emotional regulation represents normative social behavior rather than occupational burden.

Background: Lumbar radiculopathy caused by disc herniation is frequently accompanied by pain, functional disability, and impairments in sensorimotor control, including reduced proprioception and altered motor control. Interventions that integrate neural and mechanical components may enhance rehabilitation outcomes beyond exercise alone. Objectives: To investigate the effects of manual therapy combined with neurodynamic exercise and motor control exercise (MTN) with motor control exercise alone (MCE) on lumbar proprioception, motor control, and functional disability in patients with lumbar radiculopathy. Design: Randomized, single-blind clinical trial. Methods: Thirty patients with lumbar radiculopathy due to L4–S1 disc herniation were randomly assigned to either the MTN group or the MCE group. Both groups participated in supervised interventions three times per week for six weeks. The MTN group received lumbar joint mobilization and slider-based neurodynamic mobilization integrated with motor control exercise, whereas the MCE group performed motor control exercise only. Lumbar proprioception was assessed using joint position error during trunk flexion and extension. Motor control was evaluated using pressure biofeedback–based abdominal drawing- in performance. Functional disability was assessed using the Korean version of the Oswestry Disability Index. Outcomes were measured at baseline and during follow-up. Results: Significant group-by-time effects were observed for lumbar joint position error, motor control outcomes, and functional disability. The MTN group demonstrated earlier and greater improvements across all outcome measures compared with the MCE group, whereas improvements in the MCE group were more gradual. Conclusion: Compared with motor control exercise alone, the addition of manual therapy and neurodynamic exercise resulted in superior improvements in lumbar proprioception, motor control, and functional disability. An integrated MTN approach may be an effective rehabilitation strategy for patients with lumbar radiculopathy.

Background: Real-time ergonomic risk assessment in manufacturing environments is challenged by severe class imbalance in high-risk postures and the need for deployment-efficient models. Conventional oversampling techniques may violate biomechanical constraints, limiting their suitability for human motion data. Objectives: This study aimed to compare multiple machine learning models for real-time ergonomic risk assessment while addressing data imbalance using biomechanically appropriate learning strategies and evaluating both predictive performance and deployment efficiency. Design: Comparative study. Methods: A large-scale workplace safety dataset comprising image-based skeletal keypoints was analyzed. To mitigate class imbalance without generating biomechanically implausible samples, cost-sensitive learning and focal loss were employed instead of synthetic oversampling. Subject-wise data splitting was applied to prevent data leakage. Five model families, including Random Forest, convolutional neural networks, and a lightweight graphbased network, were evaluated using accuracy, F1-score, area under the receiver operating characteristic curve (AUC), and high-risk recall. Statistical significance was assessed using bootstrap confidence intervals and McNemar and DeLong tests. Results: The lightweight graph-based model demonstrated competitive classification performance while maintaining reduced computational complexity. Although none of the models achieved the predefined high-risk recall threshold, statistically significant performance differences were observed across model families. Conclusion: The findings suggest that biomechanically informed imbalance handling improves methodological validity in ergonomic risk assessment. While deployment feasibility appears promising, further empirical validation on edge hardware is required.

Background: In the South Korean private insurance sector, manual therapy faces increasing scrutiny, necessitating objective evidence for continued reimbursement. Traditional measurements often lack reproducibility or clinical practicality. Objectives: This study evaluated the feasibility of belt-stabilized hand-held dynamometry (HHD) as an objective tool for documenting strength changes and informing insurance coverage decisions. Design: A two-case clinical report. Methods: Two adult males undergoing post-operative knee rehabilitation with manual therapy were included: (1) ACL reconstruction with medial meniscus injury and (2) ORIF after knee trauma. With participants seated at the table edge and the trunk stabilized by gripping the table, knee flexion was set at 95°. Belt-stabilized HHD was used to measure isometric knee extension and flexion (three trials; maximum value recorded in N). A single examiner (>15 years’ experience) used a standardized protocol across sessions. Results: Case 1 improved from 44% (extension) and 42% (flexion) limb symmetry to 71.4% and 69.6% by session 20, supporting continued care and reimbursement after 30 sessions. Case 2 showed 60.2% extension symmetry at session 20, but subsequent reassessments lacked consistent improvement, contributing to discontinuation. Conclusion: Belt-stabilized HHD may provide a practical, low-cost method to quantify strength changes and support transparent clinician–patient–insurer communication; larger prospective studies are needed.