[Purpose] This study aimed to establish a connection between postural stability and falling in individuals with transfemoral amputation (TFA), particularly with muscle fatigue. [Participants and Methods] Fourteen participants were recruited. Muscle fatigue was induced using a sit-to-stand (STS) fatigue protocol. Pre-fatigue and post-fatigue assessments were conducted using the Biodex Balance System (BBS). [Result] The findings of the study revealed significant increases in the postural stability index between the pre-fatigue and post-fatigue conditions for the TFA group, particularly in the overall stability index (OSI) and anterior-posterior stability index (APSI) components. The mean postural stability index scores for the TFA group exhibited a percentage increase of 65.2% for OSI, 52.7% for APSI, and 50% for medial-lateral stability index (MLSI). Furthermore, the TFA fall risk index surged by 61.4%. Regarding the relationships observed, a significant correlation emerged between fall risk and both OSI and APSI. [Conclusion] These findings underscore the impact of muscle fatigue on postural stability and an increase in fall risk among TFA. By mitigating the effects of muscle fatigue, therapists can play an important role in reducing the risk of falls and promoting better postural stability in this population.

[Purpose] This study investigated the test-retest reliability of the ten-repetition maximum leg press (LP) and chest press (CP) tests in untrained young males and females. The secondary aim was to examine the test-retest reliability of the 10RM test according to gender. [Participants and Methods] All participants underwent the ten-repetition maximum test for the LP and CP across three sessions separated by 2 to 6 days of recovery: the first session was familiarization, the second for the initial test, and the third for the retest. To evaluate test-retest reliability, we calculated the intraclass correlation coefficient, standard error of measurement, and minimal detectable change for both the LP and CP. These measures were analyzed separately for each gender to assess gender-related differences. [Results] High intraclass correlation coefficient index was obtained for both LP and CP for both genderes. The standard errors of measurement and minimal detectable changes were consistent with previously reported values. However, females showed more variability than males, particularly in the LP. [Conclusion] The ten-repetition maximum test for LP and CP is a reliable method for measuring strength in untrained young males and females. However, it should be noted that the margin of error may be higher among female participants compared to their male counterparts.

[Purpose] Using new diagnostic criteria, this study aimed to clarify the relationship between respiratory sarcopenia and respiratory muscle weakness in community-dwelling older adults. [Participants and Methods] Basic information, body composition, motor function, respiratory function, and respiratory muscle strength were analyzed for 43 elderly community residents who participated in a health promotion program between 2021 and 2023. Respiratory sarcopenia and respiratory muscle weakness were evaluated based on maximal intraoral pressure and skeletal muscle index. We conducted a comparison among the three groups—respiratory sarcopenia, respiratory muscle weakness, and robustness. [Results] The respiratory sarcopenia group tended to have lower trunk muscle mass compared to the robust group and had significantly lower trunk muscle mass than the respiratory muscle weakness group. The incidence of systemic sarcopenia was significantly higher in the respiratory sarcopenia group than in the other two groups. [Conclusion] These results indicate that respiratory sarcopenia may be associated with the loss of limb muscle mass observed in patients with systemic sarcopenia and a reduction in trunk muscle mass. The risk factors influencing the prognosis of respiratory sarcopenia may vary depending on the method used to assess respiratory muscle weakness. This study provides the foundational data for future research on respiratory sarcopenia.

[Purpose] This study was aimed at investigating the relationship between skeletal muscle mass and muscle quality by using bioelectrical impedance analysis and ambulatory independence in patients with proximal femoral fractures. [Participants and Methods] The study included 120 patients admitted to a recovery rehabilitation unit for whom follow-up assessments were available. Skeletal muscle mass and phase angle were assessed using bioelectrical impedance analysis upon admission. The patients were divided into the following two groups based on their Functional Independence Measure gait score at discharge: gait-independent group (gait score: ≥6; n=74) and gait-dependent group (gait score: ≤5; n=46). [Results] The phase angle was associated with gait independence. The cut-off values for the phase angle predicting gait independence were 4° and 3.8° for male and female patients, respectively, a more accurate assessment compared with skeletal muscle mass analysis. [Conclusion] The phase angle was associated with gait independence in patients with proximal femoral fractures. The results of this study suggest that the evaluation of the phase angle is important for predicting gait independence in patients with proximal femoral fractures.

[Purpose] This study investigated the effects of differences in cane dependence on the mechanical work at the shoulder, elbow, and wrist joints during walking. [Participants and Methods] Fifteen volunteers participated in this study (mean ± standard deviation [SD] age: 24.9 ± 2.7 years, height: 1.73 ± 0.04 m, and body mass: 68.5 ± 8.9 kg). The participants walked under three conditions: (1) without a cane, (2) with a cane at 10% body weight (BW), and (3) with a cane at 20% BW. The shoulder, elbow, and wrist joint work was calculated to evaluate the mechanical load. [Results] The results indicated a significant interaction between load conditions and positive joint work, as well as between load conditions and negative joint work. The positive work in the shoulder and elbow joints significantly increased in the 20% BW condition compared to that in the 10% BW condition. [Conclusion] Increased cane dependence did not uniformly increase the positive and negative work of the shoulder, elbow, and wrist joints. Increased cane dependence during walking increases energy generation in the shoulder and elbow joints, which can result in adverse musculoskeletal strain on the shoulder and elbow joints.

[Purpose] Vibratory stimulation of the upper intercostal region enhances inspiratory movement, whereas stimulation of the lower intercostal region enhances expiratory movement and ventilation. Previous vibration stimulation devices for intercostal muscles required manual stimulation, causing a time lag between breathing and vibration stimulation. The purpose of this experiment was to compare the effects of an automatic vibration stimulation system with manual vibration stimulation in a group of individuals and to verify whether there was an increase in upper and lower chest wall displacement and respiratory flow. [Participants and Methods] Twenty healthy adults were divided into two groups, as follows: an automatic vibration stimulation group using a chest wall vibration stimulation system and a manual vibration stimulation group. Vibration stimulation was applied to the second intercostal space on both sides during inspiration, and to the seventh intercostal space on both sides during expiration. [Results] The vibration stimulation system group showed significantly higher synchronization rates during inspiration and expiration than the manual vibration stimulation group, and there was a significant increase in chest wall displacement and respiratory flow during inspiration and expiration. [Conclusion] The chest wall vibration stimulation system can effectively provide vibration stimulation to the intercostal muscles in synchrony with breathing.

[Purpose] This study aimed to determine the effects of simultaneous neuromuscular electrical stimulation (NMES) and static stretching on flexibility and muscle strength. [Participants and Methods] A randomized controlled trial was conducted with 96 healthy university students equally assigned to either a simultaneous NMES and static stretching group (Group S) or an NMES-only group (Group C). The gastrocnemius muscle was the target of both NMES and static stretching. Ankle dorsiflexion angle (DFA), forward flexion distance (FFD), and ankle plantar flexor strength (PFS) were measured before and directly following intervention. Outcomes in the two groups were evaluated using two-way analysis of variance. [Results] A significant time effect was observed for both DFA and FFD, whereas a significant interaction effect was observed for FFD only. Improvements in DFA were similar between the groups; however, improvements in FFD were significantly greater in Group S. PFS showed no significant interaction between the group and the time factor. [Conclusion] Our findings suggest that simultaneous intervention enhances flexibility. Despite targeting the gastrocnemius muscle, the observed improvement in hamstring flexibility may have been because of fascial connections. These findings support the efficacy and safety of NMES combined with static stretching for increasing flexibility.

[Purpose] The effects of multifunctional garments on neuromuscular performance have gained significant research attention in the health sciences. However, the spinal responses to different fabrics have not yet been considered. In the present study, we examined the effects of typical fabrics (cotton and polyester) on the Hoffmann reflex during local heat exposure. [Participants and Methods] Sixteen healthy males aged 20–40 years participated in this study. A heating device comprising a thermal mat, fabric, and a data logger was fabricated. The fabric was affixed to the skin as the contact surface. The temperature of the right posterior lower leg was increased to 39°C followed by 10 min for adaptation at 39–40°C. The H- and M-waves were recorded at each point, including those without heating. An identical trial was conducted seven days later using the alternative fabric. [Results] M-wave amplitude and latency were significantly decreased during heat exposure without fabric. The H-wave latency was prolonged by sustained thermal heat during the session with polyester. Interestingly, the H-wave amplitudes normalized by the maximal M-wave amplitudes decreased with prolonged heat exposure during the session with cotton. However, this index remains unchanged during the sessions using polyester. [Conclusion] During prolonged localized thermal exposure, cotton reduced spinal excitability, whereas polyester preserved spinal excitability.

[Purpose] This study aimed to elucidate the relationship between the Life-Space Assessment measure, which conceptualizes physical activity in terms of life-space, and indicators of empowerment, and physical function, in stable patients with chronic obstructive pulmonary disease. [Participants and Methods] This was a cross-sectional study. The participants were 25 stable outpatients with chronic obstructive pulmonary disease (22 males, mean age 75.6 ± 6.1 years). Measurements included the Life-Space Assessment; the Empowerment Scale for the Elderly; respiratory function; grip strength; weight-adjusted knee extension strength; and a six-minute walk test. Pearson’s correlation coefficient and a multivariate analysis were used to examine the relationship between the Life-Space Assessment and each indicator, with the significance level set at 5%. [Results] The Life-Space Assessment score (83.4 ± 23.7 points) correlated with the percentage forced vital capacity and the six-minute walk distance. However, the Life-Space Assessment demonstrated no association with the Empowerment Scale for the Elderly (38.3 ± 7.0 points). [Conclusion]The results of this study suggest that physical function correlates with scores on the Life-Space Assessment in patients with stable chronic obstructive pulmonary disease.

[Purpose] This study investigated the potential of tailored message notifications based on municipal health check-up results to improve pre-frailty and frailty in older adults. [Participants and Methods] This study was conducted in Iiyama City, Nagano Prefecture, Japan, by using the Kihon Checklist to assess the health status of older adults. Since 2019, Iiyama City has sent notifications to individuals with pre-frailty (Kihon Checklist score: 4–7) and frailty (Kihon Checklist score: ≥8). A regression discontinuity design was used to estimate the effects of the intervention by comparing the groups with scores just above and below the cutoff points. Data from 6,382 individuals aged ≥65 years from 2019 to 2022 were analyzed. [Results] The intervention slightly improved the Kihon Checklist scores in the pre-frailty group. No statistically significant effects were observed in the frailty group or after multiple imputations for missing data. [Conclusion] The findings suggest that tailored message notifications can improve frailty prevention among pre-frail older adults. However, the limited frequency and content of these messages may have reduced their effectiveness. Therefore, more frequent and targeted messages are needed to address the needs of frail individuals.

[Purpose] Higher education students face significant environmental changes, placing them at heightened risk of developing depressive symptoms that have been exacerbated by the coronavirus infectious disease pandemic. This study examined the association between psychological stress and depressive symptoms among Japanese university students. [Participants and Methods] We conducted an online and face-to-face questionnaire survey with 145 Japanese university students studying rehabilitation sciences. Depressive symptoms and psychological stress were evaluated using the Self-rating Depression Scale and Stress Response Scale-18, respectively. [Results] Among the participants, 88 had depressive symptoms. Compared to the non-depressive symptom group, the depressive symptom group experienced higher psychological stress and comprised significantly more women and individuals with insomnia. Logistic regression analysis revealed that psychological stress and insomnia were independent predictors of depressive symptoms. [Conclusion] Psychological stress is independently associated with depressive symptoms. The correlation between insomnia, stress, and depressive symptoms requires further investigation. Future research should explore the causal relationship between psychological stress and depressive symptoms and consider the factors that may influence this relationship.

[Purpose] This study aimed to investigate the differences in the acute effects of virtual and actual throwing training on throwing performance. [Participants and Methods] Twenty healthy men and six women with no boccia experience were randomly divided into the virtual and non-virtual groups. The task involved throwing boccia balls at target sets of 2 (short), 5 (middle), and 9 m (long). Both the groups were trained in three rows for each condition. The distance from the ball to the target was calculated as throwing accuracy for both pre- and post-training. Confidence in throwing was measured using a visual analog scale pre-and immediately post-training. A two-way analysis of variance with a post-hoc Bonferroni test or t-test was conducted for throwing accuracy and confidence. [Results] For throwing accuracy, the post hoc test results showed that both groups improved after training, but only in the middle-distance throw. Throwing confidence improved after training in both groups. [Conclusion] Boccia-throwing training using virtual reality may have an acute training effect comparable to that of actual training.

[Purpose] One-leg standing motion was measured in patients with Parkinson’s disease (PD) to evaluate the association between freezing of gait (FOG) and anticipatory postural adjustments (APA). [Participants and Methods] The participants included10 healthy older individuals, seven patients with PD without FOG (PD-FOG group), and seven patients with PD and FOG (PD+FOG group). An accelerometer that was built into a smartphone was attached to the lower back of each participant, and acceleration in the mediolateral direction was measured during one-leg standing. For the mediolateral component of acceleration, the time to the maximum value in the stance direction (peak latency, PL) and the amount of displacement of the maximum value (peak magnitude, PM) were analyzed as APA features. A one-way analysis of variance (ANOVA) was used to compare PL and PM among the three groups. In addition, the APA ratio (APAr), which is the ratio of PL to PM, was compared between study cohorts. [Results] Delayed PL and decreased PM were observed in the PD+FOG group, compared with the older and PD-FOG groups. In addition, APAr levels were significantly lower in the PD+FOG group. [Conclusion] Patients with PD with FOG had greater APA impairment than those with PD without FOG.

[Purpose] To characterize changes in the body composition of individuals with secondary lymphedema that developed in the early postoperative period after breast cancer surgery, before the manifestation of volume increase in the affected limb, and to test its potential as a screening indicator for preventive intervention. [Participants and Methods] A total of 219 patients with breast cancer who underwent axillary lymph node dissection and sentinel lymph node biopsy were included in this study. Body composition (extracellular water content, extracellular water content ratio, low-frequency impedance value, and phase angle) was evaluated using bioelectrical impedance analysis before surgery and three and six months after surgery. Changes in the body composition of the affected limb over time were compared between the lymphedema- and non-lymphedema-affected groups. [Results] Sixteen patients who developed lymphedema six months after breast cancer treatment showed significant changes in all body composition parameters at three months postoperatively, compared to those who did not develop lymphedema. [Conclusion] In patients with upper extremity lymphedema that develops within six months after breast cancer surgery, increases in extracellular water content, extracellular water content ratio, low-frequency impedance, and phase angle may precede apparent volume increases. Our findings suggest the usefulness of these parameters as screening indicators for early treatment triaging.

[Purpose] To examine the usefulness of automated tractography for predicting outcomes in patients with recurrent stroke. [Participants and Methods] Diffusion tensor imaging was performed in the second week after stroke, and fractional anisotropy was calculated using automated tractography. Three patients with recurrent strokes were included in this study. [Results] Initial computed tomography findings of a 62-year-old man with stuttering speech revealed a hemorrhage in the left thalamus. Fractional anisotropy indicated slight neural damage in the association fibers of both hemispheres. The patient returned to work with mild attention deficit and aphasia. Initial diffusion-weighted imaging of a 75-year-old man with right upper extremity paresis showed high-intensity areas in the left corona radiata. Fractional anisotropy indicated bilateral neural damage to the corticospinal tract. The patient was discharged with severe right upper extremity impairment and a modified gait. Initial diffusion-weighted imaging of a 60-year-old woman with moyamoya disease who experienced a sudden loss of consciousness showed high-intensity areas in the left anterior circulation territories. Fractional anisotropy indicated severe damage to the right hemisphere, the corticospinal tract, and the superior longitudinal fasciculus of the left hemisphere. She was transferred to a nursing home and remained bedridden. [Conclusion] The symptoms identified in this study agreed with automated tractography findings, which suggests that this methodology is useful for predicting recurrent stroke outcomes.

The authors would like to apologize for the mistakes in affiliations.

Incorrect:

Sho Toyoshima^{2, 3)}

Atsushi Aoki¹⁾

Yuka Yokoi^{2, 4)}

Katsuyuki Morishita^2–4)

Correct:

Sho Toyoshima^{1, 3)}

Atsushi Aoki²⁾

Yuka Yokoi^{1, 4)}

Katsuyuki Morishita^{1, 3, 4)}