Purpose: The purpose of this study was to determine how the position of tibial rotation affects peak force and hamstring muscle activation during isometric knee flexion in healthy women. Methods: Seventeen healthy women performed maximum isometric knee flexion at 30˚ with three tibial rotation positions (tibial internal rotation, neutral position, and tibial external rotation). Surface electromyographic (EMG) activity was recorded from the medial hamstring (MH) and lateral hamstring (LH) muscles. The strength of the knee flexor was measured with a load-cell-type strength-measurement sensor. Data were analyzed using one-way repeated analysis of variance. Results: The results showed that MH and LH activities and peak force were significantly different among the three tibial rotation conditions (p < 0.01). The post-hoc comparison revealed that the MH EMG activity in tibial neutral and internal rotation positions were significantly greater than tibial external rotation (p < 0.01). The LH activity in tibial external rotation was significantly greater than the tibial neutral position and internal rotation (p < 0.01). The peak force of the knee flexor was also greater in the external tibial rotation position compared with the tibial neutral and internal rotation positions (p < 0.01). Conclusion: Our findings suggest that hamstring muscle activation could be changed by tibial rotation.

Purpose: This study aims to verify the effectiveness of sit-to-stand training with visual feedback to improve balance ability and knee extensor strength of total knee replacement patients. Methods: In this study, 15 patients with total knee replacement participated in this study. Subjects were assigned to two groups: a feedback group (experimental group)(n = 8) and a control group (n = 7). They all received 30 min of continuous passive motion (CPM) and sit-to-stand training for 15 min five times per week for two weeks. Knee extensor and balance ability were measured. Knee extensor was measured by Biodex system 3; balance ability was measured by Balancia software. Results: After the intervention, there was a significant difference in the strengthening of the knee extensor muscles in the feedback group, area 95%, weight distribution of the affected side, and the sit-to-stand test repeated five times (p < 0.05). Conclusion: The results of this study showed that sit-to-stand training with visual feedback was more effective in increasing knee extensor muscle strength and balance ability than the sit-to-stand training without visual feedback. Therefore, in order to improve the knee extensor muscle and the balance of total knee replacement patients, it is necessary to consider providing visual feedback during sit-to-stand training.

Purpose: This study aimed to compare the effects of a four-week scapular stabilization exercise program using the PNF technique on scapular symmetry and range of flexion motion (ROM), pain, function, and quality of life (QOL) in post-mastectomy women with breast cancer. Methods: This study included 20 women divided into an experimental group (n = 10) and a control group (n = 10). All patients performed complex decongestive physiotherapy for 40 min daily, five times per week for four weeks. The experimental group performed the extra scapular stabilizing exercise program using the PNF technique for 50 min daily, five times per week for four weeks. Scapular symmetry, shoulder flexion ROM, pain and function, and QOL were subsequently assessed. For ROM measurement, the range of shoulder flexion was measured using a clinometer smart phone application; the pain of the shoulder was measured using the visual analogue scale (VAS); the scapular position was measured using a lateral scapular slide test (LSST); the level of pain and functional activity was measured using the Shoulder Pain and Disability Index (SPADI); and the QOL was measured using Functional Assessment of Cancer Therapy-Breast. Results: There were significant differences in shoulder flexion ROM, VAS, SPADI, and LSST 0˚ and 45˚ when the experimental group was compared with the control group (p < 0.05). After the intervention, there was an improved within-group change in the ROM, SPADI, LSST, and QOL in both the experimental and control groups. Conclusion: These findings suggest that a scapular stabilization exercise program using the PNF technique may be used as a possible treatment option for post-mastectomy women with breast cancer that aims to improve scapular position, shoulder ROM and function, and QOL.

Purpose: The purpose of this study was to investigate the effect of visual and auditory feedback combined with theraband exercise in rounded shoulder posture. Methods: There were 43 adults with rounded shoulder posture who had a distance of 2.5 cm or more from the posterolateral of the acromion to the table in the supine position that participated. The participants were randomly divided into four groups: those with visual feedback from the lateral view (visual feedback; VFB, n = 11) provided, those with auditory feedback of praise (auditory feedback; AFB, n = 10) provided, those with visual feedback and auditory feedback (visual auditory feedback; VAFB, n = 11) provided, and those without any feedback (control group; CON, n = 11). Theraband exercise with or without feedback was carried out three times per week for three weeks. To confirm the effect of theraband exercise with visual feedback and auditory feedback on pain, range of motion (ROM), posture, and psychological variables were measured before and after exercise in participants with rounded shoulder posture. Results: The VAFB group showed significant differences in pain, ROM, posture, and psychological variables when compared before and after treatment. However, the differences among the VAFB, VFB, AFB, and CON groups were significant in the ROM of abduction, the New York Posture Rating, and the scapular index. Conclusion: In conclusion, theraband exercise combined with visual feedback from the lateral view and auditory feedback by praise improved rounded shoulder posture. Moreover, auditory feedback was more significant statistically than visual feedback.

Purpose: The purpose of this study was to determine the effects of contract relaxation and a combination of isotonics in proprioceptive neuromucular facilitation (PNF) on hip and lumbopelvic motions of male patients with chronic low back pain. Methods: As the subjects of this study, a total of 45 male patients with chronic low back pain were divided into groups: 15 who underwent contract relaxation (CR) of the PNF of their hip joints, 15 who underwent a combination of isotonics (CI) of the PNF, and 15 who underwent both techniques. A device for analyzing three-dimensional motion was used to measure hip medial rotation angles, lumbopelvic rotation angles, and hip medial rotation angles at the start of lumbopelvic rotation during hip medial rotation. A two-way repeated measures ANOVA was used to compare the average values. Results: There were interactions in the hip medial rotation angles, lumbopelvic rotation angles and hip medial rotation angles at the start of lumbopelvic rotation based on the methods and periods of exercise (p < 0.05). The CR and the CR+CI groups displayed more increased hip medial angles when compared to the CI group. The CR+CI group had more decreased lumbopelvic rotation angles when compared to the CR and the CI groups. The CR+CI group had more increased hip medial rotation angles at the start of lumbopelvic rotation when compared to the CR and the CI groups. Conclusion: It can be concluded that the combination of stretching and stability exercises was effective in male patients with chronic low back pain who showed limited hip medial rotation.

Purpose: This study investigated the effects of proprioceptive neuromuscular facilitation (PNF) respiratory muscle strengthening exercise on the pulmonary function, back pain, and disability level of patients with chronic low back pain (CLBP). Methods: There were 24 CLBP patients randomly divided into the experimental group (n = 12) who took part in PNF respiratory muscle strengthening exercise and the control group (n = 12) who performed a mock treatment. Both groups performed their respective interventions for 15 min five times per week for four weeks. The pulmonary function was measured using a portable spirometer. The back pain of the participants was assessed using a visual analogue scale. The Oswestry disability index was conducted to measure disability level. A paired t-test was performed to compare within-group changes before and after the PNF respiratory muscle strengthening exercise. Differences between the experimental and the control groups were analyzed using an independent t-test. For all tests, the level of statistical significance was α = 0.05. Results: The within-group change in pulmonary function was significantly different in the experimental group (p < 0.05), and the levels of back pain and disability were significantly different between the groups (p < 0.05). There was also a significant between-group difference in pulmonary function, back pain, and disability level after intervention (p < 0.05). Conclusion: These results suggest that PNF respiratory muscle strengthening exercise enhances pulmonary function and reduces levels of back pain and disability in patients with CLBP.

Purpose: The purpose of the study was to identify the effects of proprioceptive neuromuscular facilitation (PNF) training and robot rehabilitation training on trunk stability and standing balance in individuals with chronic stroke. Methods: There were 30 patients with chronic stroke, divided into two groups: 15 subjects who received PNF and robot training (the experimental group) and 15 subjects who received standard conservative training (the control group), that participated. The experimental group received treatment for 60 min: 30 min of conventional physical therapy, 15 min of PNF training, and 15 min of robot training. The control group received conventional physical therapy for 60 min. Trunk stabilization (trunk impairment scale) and standing balance (center of pressure, limit of stability, modified functional reach test, and Berg balance scale) were measured before and after intervention. Results: Within each group, both the experimental and control groups significantly improved after the intervention in all tests; however, the experimental group showed greater improvement in scores on the trunk impairment scale, the center of pressure, the limit of stability, the modified functional reach test, and the Berg balance scale. Conclusion: The study verified that PNF training and robot training had a positive influence on trunk stability and standing balance indices in patients with chronic stroke.

Purpose: The purpose of this study was to investigate muscle activity according to knee flexion angle during single-limb-deadlift exercises. Methods: In total, 26 healthy volunteers participated. The single-limb-deadlift consisted of 0˚, 15˚, and 30˚ knee joint bending. The electromyography data were collected from the semitendinosus (SM), the biceps femoris (BF), the rectus femoris (RF), the vastus lateralis (VL), and the vastus medialis (VM). In addition, hamstrings and quadriceps (HQ) ratio was measured during the single-limb-deadlift using electromyography. Results: During the single-limb-deadlift, RF, VL, and VM were significantly higher at 30˚ bending angles compared to muscle activity of 0˚ and 15˚ knee-joint bending. The HQ ratio had significant differences in all three knee joint bending angles. In particular, the single-limb-deadlift carried out to a 30˚ knee-joint bend showed the closest value to 1. Conclusion: The most balanced coactivation ratios were observed during a single-limb-deadlift to a 30˚ knee-joint bend angle. A single-limb-deadlift at a knee-bend angle of less than 30˚ could be used as an exercise to prevent ACL injury. It could also be used for post-injury rehabilitation programs by increasing knee-joint stability.

Purpose: The purpose of this study was to determine the effects of talus stability taping during gastrocnemius stretching on ankle passive dorsiflexion, talus posterior glide, and balance in subjects with limited ankle dorsiflexion. Methods: Fifteen subjects (eight males and seven females) with limited ankle dorsiflexion participated in this study. Ankle passive dorsiflexion range of motion (ROM), talus posterior glide, and the lower quarter Y-balance test (YBT-LQ) were measured pre-stretching, after applying gastrocnemius stretching (GS), and after applying gastrocnemius stretching with talus stability taping (GSTST). The two types of stretching were performed at random. Results: Ankle passive dorsiflexion ROM was significantly increased by both types of stretching (p < 0.05), and ROM was significantly more increased post-GSTST than post-GS (p < 0.05). In addition, talus posterior glide was significantly increased post-GSTST than pre-stretching and post-GS (p < 0.05). However, there was no significant difference between post-GS and pre-stretching (p > 0.05). YBT-LQ score was significantly increased post-GSTST than pre-stretching (p < 0.05). Conclusion: Gastrocnemius stretching with talus stability taping is an effective method for subjects with limited ankle dorsiflexion to improve ankle passive dorsiflexion, talus posterior gliding, and balance.

Purpose: The human body can experience a variety of injuries. As a result, it may be difficult to directly treat the damaged area. In such a case, indirect treatment is required. Indirect treatment is typically PNF treatment. Morphological changes in muscle have been confirmed through several previous studies; however, few studies have analyzed neurological changes. Therefore, the purpose of this study was to determine how irradiation during resistance exercise using a diagonal pattern effects neurological excitability. Methods: Electromyography was performed on 13 healthy adults. A compound muscle action potential (CMAP) was obtained through a median motor nerve conduction velocity test, which was conducted before and after performing the irradiation exercise and general exercise. Results: Compared to baseline measurements, there was no significant difference in the latency of the irradiation exercise and general exercise. The amplitude of the CMAP measured after the irradiation exercise was significantly higher than after general exercise. Conclusion: Neurological excitability was high in irradiation during resistance exercise using a diagonal pattern. When clinically direct treatment is difficult, it is thought that irradiation can be used indirectly as a technique to induce nerve excitability.

Purpose: The purpose of this study was to investigate the effect of trunk-stabilization training using stabilizing reversal and rhythmic stabilization techniques of PNF on trunk muscle strength and respiratory function in elderly stroke patients. Methods: There were 26 stroke patients included in the study. Patients were divided into two groups, and all patients performed exercise 30 min five times per week for six weeks. The experimental group performed trunk stability exercise using stabilizing reversal and rhythmic stabilization techniques of PNF, and the control group performed flexibility and strength training. Trunk muscle strength, forced vital capacity, maximum inspiratory pressure, and maximum expiration pressure were measured to determine the changes after the intervention. For statistical processing, a paired t-test was performed within the group, and the value after intervention was performed as an independent t-test to find out the difference between the two groups. Results: In the experimental group, all of the trunk muscle strength, forced vital capacity, maximum inspiratory pressure, and maximum expiration pressure showed significant differences according to the intervention. In the control group, there were statistically significant differences in trunk muscle strength and forced vital capacity, but the maximum inspiratory pressure and the maximum expiration pressure did not show any statistical change. Conclusion: From these results, it can be seen that the trunk stability exercises that use the proprioceptive neuromuscular promotion method of stable reversal and rhythm stabilization can be a good intervention for the respiratory function of stroke patients.

Purpose: This study aimed to investigate basic data on the recognition of rehabilitation robots and self-efficacy through general characteristics of students in the department of physical therapy. Methods: This study surveyed 100 students in the Department of Physical Therapy at E University in Seongnam using Google Form, an online survey tool. The questionnaire consisted of 64 questions including 15 questions on general characteristics, 13 questions regarding recognition of rehabilitative robots, and 36 questions about self-efficacy. General self-efficacy consisted of three sub-factors: confidence, self-regulation efficacy, and task difficulty preference. Results: The recognition of rehabilitative robots according to general characteristics showed significant differences in age, level of education, and experience in searching rehabilitative robots; according to general characteristics, self-efficacy showed significant differences dependent on age and gender (p < 0.05). In addition, recognition of rehabilitation robots for students in the Department of Physical Therapy was found to have a significant effect on robot use self-efficacy (p < 0.05). Conclusion: There were significant differences in the scores of rehabilitation robot recognition and self-efficacy according to the general characteristics of students in the Department of Physical Therapy. For such reasons, it is important for students to have an opportunity to get educated on rehabilitation robots; in order to achieve this goal, domestic studies on rehabilitation robots must be actively conducted. The technological development of rehabilitation robots and the establishment of a system for domestic rehabilitation robots from both social and legal standpoints were found to be necessary based on a volume of domestic research.

Purpose: The purpose of this study was to determine the effect of the side-bridge exercise on the thicknesses of the external and internal obliques, the transverse abdominis, and the erector spinae, which are some of the trunk muscles of healthy adult males and females. Methods: There were 30 subjects divided into two groups with 15 subjects in the modified side-bridge exercise group and 15 subjects in the bridge exercise group. The changes in each variable were analyzed before the exercise, after three weeks, and after six weeks of exercise using a two-way repeated analysis of variance. The significance level was set at 0.05. When there was any interaction between the time of measurement and each group, a paired t-test was conducted to find the difference within groups and an independent-sample t-test was conducted to find the difference between groups. The significance level for both tests was set at 0.01. Results: There was a significant difference in the external and internal obliques and the erector spinae according to changes over time and the interactions between the time and groups (p < 0.05). However, there was a significant difference in the transverse abdominis only according to the interaction between the length of times (p < 0.05). Conclusion: The study results indicated that the modified side-bridge exercise significantly increased the thickness of the external and internal obliques and the erector spinae. This suggests the usability of the exercise in lumbar stabilization exercises in future studies and clinical fields.

Purpose: The study aimed to determine the effect of proprioceptive neuromuscular facilitation (PNF) lower trapezius muscle strengthening exercise on pain, cervical range of motion (ROM), and neck disability index (NDI) in patients with chronic neck pain. Methods: Following baseline measurements, the subjects (n = 30) with chronic neck pain were randomized into two groups: the PNF group (n = 15) that received PNF strength training of the lower trapezius muscles or a control group (n = 15) that received gentle palpation of the skin. Each group participated in the intervention for 30 min, three times per week for six weeks. The visual analogue scale for pain, ROM, and NDI of both groups were recorded at both pre- and post-intervention. Paired t-tests were used to determine significant changes in the post-intervention compared with pre-intervention, and independent t-tests were used to analyze differences in the dependent variables between the two groups. Results: After the six-week intervention, both groups experienced significantly decreased pain and NDI (p < 0.05) and significantly increased cervical flexion, extension, lateral flexion, and rotation ROM (p < 0.05). The PNF group that received PNF strength exercise of the lower trapezius muscles showed greater improvements in pain and NDI and cervical rotation of ROM than those of the control group (p < 0.05). Conclusion: These results suggest that the PNF lower trapezius strengthening exercise reduces neck pain and disability level and enhances cervical ROM in patients with chronic neck pain.

Purpose: This study was conducted to investigate the functional differences of the two heads of the biceps brachii by measuring the functions in supination according to pronation by the angle of the flexion of the elbow joint, except for the activities of the elbow flexors. Methods: This study was conducted with 25 healthy men in their 20s. At a glenohumeral-joint 0˚ flexion posture, angles of flexion of the elbow joint of 0˚, 30˚, 60˚, 90˚, and 120˚ were randomly provided, and they were asked to perform supination and pronation with an elastic band. Using an eight-channel surface electromyogram, the muscle activities of the long and short heads of the biceps brachii were measured. The activities of the short and long heads according to the angle were analyzed using a one-way ANOVA, and as a post-test, LSD was employed. Results: The analysis of the impact of the resistance of the elastic band in supination on the differences in the muscle activities in the short and long heads suggests there was a significant difference between 0˚ and 30˚ (p < 0.05). Conclusion: In supination according to forearm pronation, the long head had greater action in the early flexion posture of the elbow joint, and it is judged that the ratio of the flexion of the elbow joint according to the actions of the biceps brachii was considered small.