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Purpose: This study aimed to investigate the effects of virtual reality–based biofeedback training on pain and knee function under different support surface conditions in patients with patellofemoral pain syndrome (PFPS), and to compare the magnitude of training effects between unstable and stable support surfaces. Methods: Thirty patients diagnosed with PFPS were randomly assigned to either an experimental group (n = 15) or a control group (n = 15). Both groups received conventional physical therapy in addition to virtual reality–based biofeedback training conducted three times per week for four weeks. The experimental group performed the training on an unstable support surface, whereas the control group trained on a stable support surface. Pain intensity was assessed using the Visual Analog Scale (VAS), and knee function was evaluated using the Korean version of the Western Ontario and McMaster Universities Osteoarthritis Index (K-WOMAC). Within-group changes were analyzed using the paired t-test, and between-group differences were examined using an analysis of covariance (ANCOVA) with baseline values as covariates. Results: Both groups showed significant improvements in VAS and K-WOMAC scores after the intervention (p < 0.01). However, the between-group differences did not reach statistical significance after adjustment for baseline values (VAS: adjusted mean difference = −1.17, 95 % CI: −2.20 to −0.14, p = 0.027; K-WOMAC: adjusted mean difference = −3.68, 95 % CI: −7.25 to −0.10, p = 0.044). Upon application of Bonferroni correction (adjusted α = 0.025), neither comparison reached statistical significance. Conclusion: Virtual reality–based biofeedback training was effective in reducing pain and improving knee function in patients with PFPS. Although no statistically significant between-group differences were identified, the experimental group demonstrated greater improvements in both outcome measures when trained on an unstable support surface. These findings suggest that incorporating unstable surfaces into VR-based biofeedback training may provide additional therapeutic benefits; however, further well-powered studies with larger sample sizes are required to confirm these effects.

Purpose: Maintaining balance against sudden support-surface translation involves complex muscle coordination. This study aimed to systematically synthesize the experimental procedures and muscle coordination analysis methods used in studies of postural control in response to support-surface translation. Methods: This methodological review initially identified 118 studies using support-surface translation with electromyography (EMG) measurements in standing posture via Google Scholar and PubMed. After applying exclusion criteria including animal experiments and theses, a final total of 20 studies were selected. Results: The results revealed that while the experimental methods across these studies of postural control using surface-moving perturbations were relatively similar in EMG signal processing, no standardized parameter settings existed for platform movement procedures or muscle coordination analysis. Conclusion: These results highlight the risk of Type I or Type II errors due to the non-standardization of experimental and analytical methods across studies, indicating that a clear understanding of the principles and limitations of each procedure or analysis method is essential during study design. The findings of this study are expected to contribute to establishing platform movement parameters, EMG measurement, and muscle coordination analysis methods in future studies on postural control in response to support-surface translation.

Purpose: Standard foot core exercises are typically performed in a neutral ankle position, potentially neglecting the biomechanical influence of the muscle length-tension relationship. This study examined the effects of ankle joint angles (neutral vs. 30° dorsiflexion) and specific foot exercises (short foot [SF], toe curl [TC], and toe spread [TS]) on the electromyographic activity of the abductor hallucis (AH) and tibialis anterior (TA) in adults with flexible flatfoot. Methods: Thirty young adults with flexible flatfoot performed SF, TC, and TS exercises in a weight-bearing standing posture under neutral and 30° dorsiflexed ankle conditions using a custom wedge board. Surface electromyography was used to assess the normalized muscle activation (%RVC) of the AH and TA. A 2×3 repeated-measures ANOVA was used to analyze main and interaction effects. Results: A significant interaction between ankle angle and exercise type was observed for AH activation (p = .020); TS elicited the highest AH activity in the neutral position (62.33%), whereas SF maximized AH recruitment at 30° dorsiflexion (64.53%). In contrast, TA activation demonstrated no significant interaction (p = .412) but exhibited significant independent main effects. TA activity significantly increased during 30° dorsiflexion compared with the neutral condition (58.68% vs. 45.41%, p < .001) and was highest during the TC exercise (67.15%, p < .001). Conclusion: Sagittal plane ankle kinematics fundamentally govern the selective recruitment of foot musculature. Manipulating ankle dorsiflexion may enable clinicians to selectively isolate intrinsic muscles or synergistically co-activate extrinsic stabilizers, providing a sound biomechanical foundation for precision rehabilitation in flexible flatfoot.

Purpose: This study aimed to examine the immediate effects of yoga nidra on relative theta power and sensorimotor rhythm (SMR) in patients with stroke. Methods: This study employed a single-group pretest-posttest design; data from 14 patients with stroke were analyzed. Electroencephalography (EEG) was recorded before and immediately after a single session of yoga nidra. Relative theta power and relative SMR were calculated from EEG signals. Pre- and post-intervention values were compared using paired t-tests or the Wilcoxon signed-rank test, as determined by normality assessment. False discovery rate (FDR) correction was applied to adjust for multiple comparisons, and effect sizes were calculated. Statistical significance was set at α = .05. Results: Relative theta power showed no statistically significant differences across all electrodes either before or after FDR correction. Relative SMR showed a significant decrease only at the Fp1 electrode before correction (p = .034), with a moderate effect size (Cohen’s dz = .632). However, this finding did not survive FDR correction (adjusted p = .646). Conclusion: A single session of yoga nidra did not produce statistically significant changes in relative theta power or relative SMR following correction for multiple comparisons in patients with stroke. Although a pre-correction decrease in relative SMR was observed at Fp1, this finding should be interpreted with caution. These results may provide pilot data for future EEG-based studies examining the effects of yoga nidra in patients with stroke.

Purpose: This study investigated the effects of visual feedback-based eccentric pulley training (EPT) on static and dynamic balance in patients with low back pain (LBP). Methods: A total of 54 participants were randomly divided into three groups: 18 in the visual feedback-based EPT (VF-EPT) group, 18 in the EPT group, and 18 in the eccentric training (ET) group. The VF-EPT group performed pulley eccentric training with visual feedback; the EPT group received pulley eccentric training without visual feedback; and the ET group performed eccentric training only, without visual feedback or a pulley. All groups trained for 30 minutes per session, three times per week for four weeks. Static balance was assessed using the Single-Leg Standing Test (SLST), and dynamic balance was assessed using the Star Excursion Balance Test (SEBT). Results: Balance ability improved significantly only in the VF-EPT group (p < 0.05), and significant between-group differences were also observed (p < 0.05). Conclusion: These results suggest that visual feedback-based eccentric pulley training may be effective in improving both static and dynamic balance in patients with LBP.

Purpose: This study aimed to investigate the effects of squat training performed on different support surfaces on lower limb muscle oxygen saturation (SmO2), muscle activity, and walking ability in individuals with chronic stroke. Methods: Thirty participants with chronic stroke were randomly assigned to an experimental group (unstable surface squat training, n = 15) or a control group (stable surface squat training, n = 15). Both groups received conventional physical therapy in addition to squat training three times per week for six weeks. Muscle oxygen saturation of the vastus lateralis and medial gastrocnemius was measured using near-infrared spectroscopy. Muscle activity of the rectus femoris, biceps femoris, and gastrocnemius was assessed using surface electromyography. Walking ability was evaluated using the 6-Minute Walk Test (6MWT). Data were analyzed using a two-way repeated-measures ANOVA. Results: Muscle oxygen saturation showed significant time effects in both the vastus lateralis (p = 0.004) and medial gastrocnemius (p < 0.001), with no significant group × time or interaction effects. Muscle activity demonstrated significant group × time interactions in the rectus femoris (p < 0.001), biceps femoris (p < 0.01), and gastrocnemius (p < 0.05), with the experimental group showing greater improvements. Walking ability also showed a significant group × time interaction (p < 0.05), with significant improvement observed only in the experimental group. Conclusion: Unstable surface squat training appeared more effective than stable surface training in improving neuromuscular activation and walking ability in individuals with chronic stroke. These findings suggest that incorporating unstable support surfaces into rehabilitation programs may enhance functional recovery by promoting neuromuscular adaptations.

Purpose: This study investigated the effects of laser-based neck sensorimotor training on cognitive dual-task gait performance in community-dwelling older adults. Methods: Twenty-four older adults were randomly assigned to an experimental group (n = 12) or a control group (n = 12). Both groups trained three times per week for six weeks. The experimental group performed laser-based neck sensorimotor training using a head-mounted laser device, whereas the control group performed a general neck exercise program. Outcome measures included the 10-Meter Walk Test under single-task and cognitive dual-task conditions, dual-task cost (DTC), the Timed Up and Go dual-task test (TUGdt), the Functional Gait Assessment (FGA), and cervical movement sense error (MSE). Within-group changes were analyzed using the paired t-test, and between-group differences were analyzed using ANCOVA with baseline values as covariates. Results: The experimental group showed significant improvements in single-task gait speed, cognitive dual-task gait speed, DTC, TUGdt, FGA, and MSE after the intervention (all p < .001). The control group showed significant improvements in single-task gait speed and TUGdt (both p < .001), FGA (p = .003), and MSE (p = .034), whereas changes in cognitive dual-task gait speed (p = .386) and DTC (p = .831) were not significant. Between-group comparisons revealed significantly greater improvements in the experimental group for single-task gait speed, TUGdt, FGA, and MSE (all p < .001), cognitive dual-task gait speed (p = .006), and DTC (p = .003). Conclusion: Laser-based neck sensorimotor training demonstrated superior effects on cognitive dual-task gait performance, functional mobility, functional gait ability, and cervical movement sense in community-dwelling older adults relative to general neck exercise.

Purpose: This study investigated the influence of state anxiety on heart rate (HR) response during experimentally evoked musculoskeletal pain in healthy adults and examined whether HR response was associated with self-reported pain intensity after controlling for anxiety. Methods: Thirty healthy adults participated in this one-group repeated-measures experimental study. Experimental pain was induced using a digital pressure algometer (FPX 25; Wagner Instruments, Greenwich, CT, USA) applied perpendicularly to the dominant forearm flexor muscle belly. Pain intensity was assessed immediately after stimulation using the Numeric Rating Scale (NRS). HR was recorded using a chest-strap heart rate sensor (Polar H10; Polar Electro Oy, Kempele, Finland). State anxiety was assessed using the State-Trait Anxiety Inventory–State form (STAI-State). HR was measured at baseline, during pain stimulation, and during recovery. Data were analyzed using a repeated-measures ANOVA, Pearson correlation, and multiple regression. Results: HR differed significantly across the baseline, pain stimulation, and recovery phases. HR during pain stimulation was significantly higher than that during baseline and recovery, and HR during recovery remained significantly higher than that at baseline. NRS pain intensity was positively correlated with HR change, and STAI-State score was also positively correlated with HR change. However, after controlling for state anxiety, pain intensity was no longer a significant predictor of HR change, whereas state anxiety remained a significant predictor. Conclusion: HR response during experimentally evoked musculoskeletal pain may reflect not only pain intensity but also the influence of state anxiety. Accordingly, HR should be interpreted as an adjunctive physiological indicator rather than a direct measure of pain intensity.

Background: Sports taping is widely used in musculoskeletal rehabilitation; however, evidence comparing the clinical effects of different taping materials remains limited. Purpose: This study aimed to systematically compare the clinical effects of rigid tape, Kinesio Tape, and dynamic tape based on high-quality randomized controlled trials (RCTs). Methods: A systematic review was conducted in accordance with the PRISMA 2020 guidelines. Literature published between 2000 and 2025 was searched in PubMed, Scopus, Web of Science, and the Cochrane Library, with additional searches conducted in Korean databases. Only RCTs with a PEDro score ≥6 were included. A total of 10 studies were selected and analyzed. Results: All three taping materials were associated with beneficial effects on pain reduction and functional improvement. Rigid tape was associated with consistent improvements in mechanical stabilization and joint realignment. Kinesio Tape was associated with short-term pain relief and range of motion improvement. Dynamic tape demonstrated favorable effects in improving muscular endurance and functional performance, particularly in conditions involving repetitive loading. However, several studies included combined interventions, which may limit the interpretation of taping-specific effects. Conclusion: Taping may serve as a useful adjunct intervention in musculoskeletal rehabilitation. The selection of taping material should be based on the patient’s clinical condition and therapeutic goals. Rigid tape may be considered for mechanical stabilization, Kinesio Tape for short-term symptom modulation, and dynamic tape for load management and functional support.

Purpose: Dizziness and balance impairment are major risk factors for falls in older adults. While grip strength decline and depressive symptoms are independently associated with balance problems, few studies have examined their combined effects in community-dwelling adults aged 65 years and older. Methods: This cross-sectional study analyzed data from the 2019, 2022, and 2023 Korean National Health and Nutrition Examination Survey (KNHANES), comprising 3,407 participants aged 65 years or older. Grip strength was measured using a digital dynamometer, and low grip strength was defined according to the 2019 Asian Working Group for Sarcopenia (AWGS) criteria (men <28 kg, women <18 kg). Depressive symptoms were assessed by asking whether participants had experienced persistent feelings of sadness or hopelessness for two consecutive weeks. Participants were classified into four groups: (1) normal grip strength with no depressive symptoms (reference group), (2) low grip strength only, (3) depressive symptoms only, and (4) both conditions combined. Complex sample logistic regression analyses were conducted using SPSS 29.0, adjusting for sex, age, education, income, smoking, alcohol use, hypertension, diabetes, and survey year. Results: The weighted prevalence of dizziness or balance impairment was 38.2%. In the fully adjusted model, adjusted odds ratios (AOR) relative to the reference group were as follows: low grip strength only, 1.23 (95% CI: 0.94–1.61, p = 0.132); depressive symptoms only, 2.18 (95% CI: 1.59–3.01, p < 0.001); and combined, 2.21 (95% CI: 1.16–4.20, p = 0.016). No significant interaction effect was observed (p = 0.462). Conclusion: Depressive symptoms showed a stronger association with dizziness and balance impairment than grip strength decline, with no synergistic effect between the two factors. These findings suggest that screening for depressive symptoms should be prioritized alongside physical assessments in fall prevention programs for older adults.

Purpose: This study compared the effects of three different exercise interventions on neck biomechanics, muscle tone, and functional disability in adults with forward head posture (FHP). Methods: Thirty adults with FHP were randomly assigned to a cranio-cervical flexion exercise group (CCFEG, n = 10), a modified extension exercise group (MEEG, n = 11), or a self-myofascial release and static stretching group (SMR&SS, n = 9). Interventions were conducted twice weekly for six weeks. The craniovertebral angle (CVA), cervical range of motion (ROM), sternocleidomastoid (SCM) and upper trapezius (UT) muscle tone, Neck Disability Index (K-NDI), and Visual Analogue Scale (VAS) were assessed before and after the intervention. Results: CVA, K-NDI, and VAS scores improved significantly in all groups (p < .05). Regarding ROM, significant improvements were observed in the CCFEG and MEEG (p < .05), whereas the SMR&SS group showed no statistically significant change (p > .05). Regarding muscle tone, left SCM tone decreased significantly in all groups (p < .05), whereas right SCM tone decreased significantly only in the CCFEG and MEEG (p < .05). The MEEG showed the greatest numerical improvements in K-NDI, VAS, and right SCM tone; however, no statistically significant between-group differences in change scores were observed (p > .05). No significant changes were found in UT muscle tone. Conclusion: All three active exercise interventions effectively improved neck function, muscle tone, and postural alignment in adults with FHP. SMR&SS yielded the largest numerical improvement in CVA, whereas the modified extension exercise produced the greatest numerical improvements in pain, disability, and SCM muscle tone reduction. The selection of these exercises should be guided by individual symptoms and functional characteristics.

Purpose: This pilot study compared the effects of six-week static and dynamic core exercise programs on physical fitness outcomes in college students. Methods: Twelve participants were randomly assigned to either a static core exercise group (n = 6) or a dynamic core exercise group (n = 6) using simple randomization. Each group performed a specific core exercise protocol for 30 minutes per session, twice per week, for six weeks. Progressive overload was implemented by gradually increasing the number of sets. Back strength, trunk muscular endurance, and dynamic balance were assessed before and after the intervention. Results: Both groups showed significant improvements in abdominal and lateral trunk muscle endurance (p < .05). The static core exercise group showed superior gains in lumbar extensor endurance (p < .05), whereas the dynamic core exercise group demonstrated significant improvements in bilateral Y-Balance Test (YBT) composite scores (p < .05). No significant changes were observed in maximal back strength in either group (p > .05). Conclusion: Static core exercises may be effective in developing isometric spinal stability, whereas dynamic core exercises may be superior in improving neuromuscular coordination and dynamic balance. Given the preliminary nature of these findings, future well-powered studies with larger sample sizes and an active non-exercise control group are warranted to confirm these findings and evaluate long-term effects.

Purpose: This study examined the effects of sustained natural apophyseal glides (SNAGs) combined with active neural mobilization techniques on pain, the Neck Disability Index (NDI), and range of motion (ROM) in patients with cervical radiculopathy. Methods: Thirty patients who attended W Hospital in Seoul and fulfilled predefined inclusion criteria were randomly assigned to one of two groups: an experimental group (manual therapy, exercise program, and electrotherapy with SNAGs and active neural mobilization [n = 15]) and a control group (manual therapy, exercise program, and electrotherapy [n = 15]). Results: The experimental group showed statistically significant improvements in visual analog scale pain scores and NDI compared with the control group following treatment (p < .05). Similarly, the experimental group exhibited a statistically significant improvement in the ROM of cervical rotation on the affected side compared with the control group after the intervention (p < .05). Conclusion: SNAGs combined with active neural mobilization techniques were effective in decreasing pain and improving neck function and activities of daily living in patients with cervical radiculopathy.