Yeong-Bin Choi⋅Jin-Woo Jang⋅Min-Su Kang⋅Young-Min Choi⋅Hyun-Soo Jin⋅Jun-Hyeok Go, P.T., Ph.D.⋅Jeong-Seon Kim, P.T., Ph.D.⋅Ji-Hye Kim, P.T., Ph.D.⋅ Won-Deok Lee, P.T., Ph.D⋅Yu-Sung Jang, P.T., M.sc.. PNF and Movement 2025;23:255-64. https://doi.org/10.21598/JKPNFA.2025.23.2.255

Purpose: This study aimed to investigate the characteristics of lower extremity muscle activity, isokinetic strength, range of motion, and balance in ballet dancers with chronic ankle instability (CAI) to provide fundamental data for injury prevention and rehabilitation strategies.Methods: Female ballet dancers were divided into the CAI (n = 20) and control (n = 10) groups.EMG analysis evaluated muscle activity in the tibialis anterior, peroneus longus, and gastrocnemius during four ballet movements: arabesque relev, pass relev, first position relev, and first position jump.Isokinetic ankle strength was measured at three angular velocities (60/sec, 120/sec, and 180/sec) for inversion, eversion, plantar flexion, and dorsiflexion movements.The ankle range of motion (ROM) was assessed using goniometry. Results:The CAI group showed significantly decreased ankle strength at 60/sec across all motions.Notably, plantar flexion strength was 50.8% lower than that in the control group.ROM analysis revealed increased inversion ROM (9.11) and decreased eversion ROM (10.5) in the CAI group.EMG analysis demonstrated 34% higher peroneus longus activation during arabesque relev in CAI dancers than in the controls.Conclusion: Ballet dancers with CAI demonstrate specific neuromuscular adaptations, including decreased isokinetic strength at low velocities, directional ROM imbalances, and compensatory muscle activation patterns.Rehabilitation programs should focus on low-velocity strength training, correcting frontal plane ROM imbalances, and functional peroneus longus training integrated with ballet-specific movements.

Purpose: Structural changes in the foot, particularly pes planus, lead to internal rotation of the tibia and femur, subsequently increasing pelvic anteversion.This biomechanical adaptation in the pelvis and lower extremities affects the lumbar spine, resulting in an increase in lumbar lordotic curvature.This study aimed to analyze whether lumbar spinal alignment changes occur in asymptomatic flexible pes planus and to evaluate the corrective effects of low-Dye taping and modified Mulligan taping, which are commonly used in the treatment of flexible pes planus, by examining their potential to induce changes in lumbar lordotic curvature.Methods: This study was conducted with 30 voluntarily participating individuals who exhibited bilateral flexible pes planus.Improvement in flexible pes planus following taping application was assessed using the navicular drop test, while changes in lumbar lordotic curvature were analyzed using a flexible curve ruler.The corrective effects of each taping method on pes planus and the degree of lumbar lordotic curvature alteration were examined through one-way repeated measures ANOVA and contrast tests.Results: Application of low-Dye taping and modified Mulligan taping resulted in a significant increase in the height of the navicular tuberosity compared to the pre-taping condition.However, no significant abnormality in lumbar lordotic curvature was observed in individuals with asymptomatic flexible pes planus, and neither taping intervention induced a significant change in lumbar lordotic curvature. Conclusion:In asymptomatic flexible pes planus, both low-Dye taping and modified Mulligan taping were effective in correcting flexible pes planus.However, neither intervention induced significant changes in lumbar lordotic curvature.

Purpose: The aim of this study was to compare the abdominal muscle activity and thickness of the convex and concave sides of men with mild scoliosis.Methods: This study employed 16 male participants with mild scoliosis (Cobb's angle: 1020).We investigated the differences in muscle activity and thickness of the rectus abdominis (RA), external oblique (EO), and internal oblique (IO) on the convex and concave sides according to mild scoliosis.Muscle activation was measured in the curl-up and plank positions using electromyography, and muscle thickness was measured during maximal exhalation using ultrasound.Results: In terms of muscle activation, the RA and IO muscle activities on the convex side were higher than on the concave side in the curl-up position (RA: p < 0.01, IO: p < 0.01).In the plank position, the RA and IO muscle activities on the concave side were higher than on the convex side (RA: p < 0.01, IO: p < 0.01).In terms of muscle thickness, there was no significant difference in any muscle (RA, EO, or IO) between the convex and concave sides according to scoliosis. Conclusion:According to the results, there was a significant difference in abdominal muscle activity between the convex and concave sides according to mild scoliosis.However, in terms of abdominal muscle thickness, there was no significant difference between the convex and concave sides.Therefore, the results of this study show that mild scoliosis affects abdominal muscle function, such as muscle activity, but does not change abdominal muscle structure.

Purpose: To explore the effects of action observation combined with modified constraint-induced movement therapy on upper-extremity function and the activities of daily living in subacute stroke patients. Methods: Twenty-four subacute stroke patients were randomly assigned to the experimental group or the control group (n = 12 each). Both groups received therapy based on motor learning concepts, including repetitive and task-specific practice. The experimental group watched video clips for 10 minutes related to tasks performed during modified constraint-induced movement therapy while the control group watched videos unrelated to upper-extremity movement. These programs were performed for 40 minutes a day five times a week for four weeks. Their scores on the Fugl–Meyer assessment of upper extremities (FMA-UE), the action research arm test (ARAT), a motor activity log (amount of use [AOU] and quality of movement [QOM]), and the modified Barthel index (MBI) were recorded. Results: In both groups, all variables were significantly different between the pre-test and post-test periods (p < 0.05). The post-test variables were significantly different within each group (p < 0.05). In the experimental group, the changes between pre-test and post-test scores in the FMA-UE (14.39 ± 4.31 versus 6.31 ± 4.63), the ARAT (16.00 ± 4.73 versus 11.46 ± 3.73), MAL-AOU (1.57 ± 0.15 versus 1.18 ± 0.28), and MBI (27.54 ± 4.65 versus 18.08 ± 8.52) were significantly higher than those of the control group (p < 0.05). Conclusion: These findings suggest that action observation combined with modified constraint-induced movement therapy may be a beneficial rehabilitation option to improve upper-extremity function in subacute stroke patients with moderate impairment.