The Effects of Prolonged Sitting in a Cross-legged Posture on Pulmonary Function in Young Adults

Purpose@#The impact of prolonged sitting in a cross-legged posture on physiological factors has not been extensively studied. We therefore attempted to evaluate whether prolonged sitting in a cross-legged posture affects pulmonary function in normal young adults. @*Methods@#Twenty-four participants were recruited in this study, and the participants were equally allocated to the normal sitting posture group (NSP group, n = 12) or sitting posture with the cross-legs group (SPCL group, n = 12). The NSP group sat on chairs without crossing their legs for 30 minutes, and the SPCL group sat on the chair with legs crossed (the right knee on the left knee or the left knee on the right knee) for 30 minutes. The pulmonary function of the subjects was evaluated based on forced vital capacity (FVC), forced expiratory volume in one second (FEV1), FVC/FEV1, and peak expiratory flow (PEF) measured using a spirometer. @*Results@#In the intra-group comparison, the SPCL group showed significant differences in FVC and FEV1 before and after sitting (p 0.05) were observed in the NSP group. However, there were no significant differences between the two groups in the pulmonary function parameters measured before and after sitting (p > 0.05). @*Conclusion@#Our results confirmed that prolonged sitting in a cross-legged posture could have a negative influence on pulmonary function. Therefore, if a sitting position is maintained for a long time, the correct sitting posture should be maintained to prevent musculoskeletal disorders as well as to maintain normal pulmonary function.

Effects of Heel-insole on Static Balance and Postural Strategy during External Perturbation in Healthy Young Men

Purpose@#This study examined the effects of heel insoles on the static balance and leg muscle activity and posture control strategy during external perturbation. @*Methods@#Thirty healthy young men participated in the study. The subjects underwent two experimental conditions: 1) no heel insole condition (0cm) and 2) wearing heel insole condition (5cm). The static balance was measured using an I-Balance device, which measured the change in the center of gravity (COG). The onset time of muscle activation and muscle activation of the erector spinae (ES), hamstring (HAM), gastrocnemius (GCM) were measured using surface EMG electrodes to determine the change in posture control strategy during external perturbation. @*Results@#The speed and distance of COG were significantly higher in the wearing heel insoles condition than the no heel insole condition (p<0.05). In addition, significant differences in the onset time of the GCM, HAM, and ES muscle activation were observed when there was no heel insole condition during external perturbation (p<0.017). On the other hand, no significant differences in the onset time of muscle activation were observed between GCM and HAM when wearing the heel insole condition during external perturbation (p<0.017). Moreover, muscle activation of the GCM was significantly higher in the wearing heel insoles condition than the no heel insole condition during external perturbation (p<0.05). @*Conclusion@#These findings suggest that heel insoles may have disadvantages, and increased efforts are needed to maintain balance and change the posture control strategy during external perturbation

Effects of Heel-insole on Static Balance and Postural Strategy during External Perturbation in Healthy Young Men

Purpose@#This study examined the effects of heel insoles on the static balance and leg muscle activity and posture control strategy during external perturbation. @*Methods@#Thirty healthy young men participated in the study. The subjects underwent two experimental conditions: 1) no heel insole condition (0cm) and 2) wearing heel insole condition (5cm). The static balance was measured using an I-Balance device, which measured the change in the center of gravity (COG). The onset time of muscle activation and muscle activation of the erector spinae (ES), hamstring (HAM), gastrocnemius (GCM) were measured using surface EMG electrodes to determine the change in posture control strategy during external perturbation. @*Results@#The speed and distance of COG were significantly higher in the wearing heel insoles condition than the no heel insole condition (p<0.05). In addition, significant differences in the onset time of the GCM, HAM, and ES muscle activation were observed when there was no heel insole condition during external perturbation (p<0.017). On the other hand, no significant differences in the onset time of muscle activation were observed between GCM and HAM when wearing the heel insole condition during external perturbation (p<0.017). Moreover, muscle activation of the GCM was significantly higher in the wearing heel insoles condition than the no heel insole condition during external perturbation (p<0.05). @*Conclusion@#These findings suggest that heel insoles may have disadvantages, and increased efforts are needed to maintain balance and change the posture control strategy during external perturbation

Cross-education Effects of Muscle Strength and Balance on Unilateral Isokinetic Exercise in Ankle

Purpose@#Unilateral strength training effects on contralateral sides have been demonstrated in previous studies for lower extremity exercise, upper extremity exercise, and unilateral surface electrical stimulation. This study was performed to investigate the effects of unilateral ankle training on muscle strength and the balance of contralateral lower extremity in healthy adults. @*Methods@#Thirty healthy subjects were randomized equally to a training or a control group. Those in the training group received unilateral ankle isokinetic strengthening training of the dominant leg (right side) for 4 weeks. Contralateral single-limb balance, including Anterio-Posterior Stability Index (APSI), Medio-Lateral Stability Index (MLSI) and Overall Stability Index (OSI), was assessed before and after intervention. @*Results@#Comparison of pre- and post-test data revealed significant improvements in ipsi- and contralateral ankle strengths, and significant improvement in contralateral single limb balance. @*Conclusion@#These results have practical implications because they demonstrate that unilateral ankle isokinetic exercise improves ankle muscle strength and balance ability of contralateral lower extremity.

Effect of Action Observation Training Using Y-Balance on Balance Capability in Young Adults

Purpose@#This study examined the effects of action-observation training using the Y-Balance on the balance ability of young adults. @*Methods@#Thirty-four healthy adults were randomized into an action-observation group (n=17) or a control group (n=17). All subjects performed the Y-Balance test before and after watching the video. The action observation group watched a video of someone performing a Y-Balance test, and the control group watched a video of scenery unrelated to the training. The subjects were measured through a Y-Balance test for both the length of the legs extended in three directions and the Y-balance composite score. @*Results@#A significant difference in the Y-balance composite score was observed between the two groups. A part of the direction of the extended leg in the action observation group was increased significantly (posteromedial direction of the right leg, posterolateral direction of the right leg, posteromedial direction of left leg) compared to the control group. @*Conclusion@#These results suggest that action observation training only could help improve balance.

Dose Motor Inhibition Response Training Using Stop-signal Paradigm Influence Execution and Stop Performance?

Purpose@#This study examined whether 1) the motor inhibition response as cognitive-behavioral component is learning though a stop signal task using stop-signal paradigm, and 2) whether there is a difference in the learning degree according to imagery training and actual practice training. @*Methods@#Twenty young adults (males: 9, females: 11) volunteered to participate in this study, and were divided randomly into motor imagery training (IT, n=10) and practice training (PT, n=10) groups. The PT group performed an actual practice stop-signal task, while the IT group performed imagery training, which showed a stop-signal task on a monitor of a personal computer. The non-signal reaction time and stop-signal reaction time of both groups were assessed during the stop-signal task. @*Results@#In the non-signal reaction time, there were no significant intra-group and inter-group differences between pre- and post-intervention in both groups (p>0.05). The stop-signal reaction time showed a significant difference in the PT group in the intra-group analysis (p0.05). @*Conclusion@#These results showed that the motor inhibition response could be learned through a stop-signal task. Moreover, these findings suggest that actual practice is a more effective method for learning the motor inhibition response.

Cross-education Effects of Muscle Strength and Balance on Unilateral Isokinetic Exercise in Ankle

Purpose@#Unilateral strength training effects on contralateral sides have been demonstrated in previous studies for lower extremity exercise, upper extremity exercise, and unilateral surface electrical stimulation. This study was performed to investigate the effects of unilateral ankle training on muscle strength and the balance of contralateral lower extremity in healthy adults. @*Methods@#Thirty healthy subjects were randomized equally to a training or a control group. Those in the training group received unilateral ankle isokinetic strengthening training of the dominant leg (right side) for 4 weeks. Contralateral single-limb balance, including Anterio-Posterior Stability Index (APSI), Medio-Lateral Stability Index (MLSI) and Overall Stability Index (OSI), was assessed before and after intervention. @*Results@#Comparison of pre- and post-test data revealed significant improvements in ipsi- and contralateral ankle strengths, and significant improvement in contralateral single limb balance. @*Conclusion@#These results have practical implications because they demonstrate that unilateral ankle isokinetic exercise improves ankle muscle strength and balance ability of contralateral lower extremity.

Effect of Action Observation Training Using Y-Balance on Balance Capability in Young Adults

Purpose@#This study examined the effects of action-observation training using the Y-Balance on the balance ability of young adults. @*Methods@#Thirty-four healthy adults were randomized into an action-observation group (n=17) or a control group (n=17). All subjects performed the Y-Balance test before and after watching the video. The action observation group watched a video of someone performing a Y-Balance test, and the control group watched a video of scenery unrelated to the training. The subjects were measured through a Y-Balance test for both the length of the legs extended in three directions and the Y-balance composite score. @*Results@#A significant difference in the Y-balance composite score was observed between the two groups. A part of the direction of the extended leg in the action observation group was increased significantly (posteromedial direction of the right leg, posterolateral direction of the right leg, posteromedial direction of left leg) compared to the control group. @*Conclusion@#These results suggest that action observation training only could help improve balance.

Dose Motor Inhibition Response Training Using Stop-signal Paradigm Influence Execution and Stop Performance?

Purpose@#This study examined whether 1) the motor inhibition response as cognitive-behavioral component is learning though a stop signal task using stop-signal paradigm, and 2) whether there is a difference in the learning degree according to imagery training and actual practice training. @*Methods@#Twenty young adults (males: 9, females: 11) volunteered to participate in this study, and were divided randomly into motor imagery training (IT, n=10) and practice training (PT, n=10) groups. The PT group performed an actual practice stop-signal task, while the IT group performed imagery training, which showed a stop-signal task on a monitor of a personal computer. The non-signal reaction time and stop-signal reaction time of both groups were assessed during the stop-signal task. @*Results@#In the non-signal reaction time, there were no significant intra-group and inter-group differences between pre- and post-intervention in both groups (p>0.05). The stop-signal reaction time showed a significant difference in the PT group in the intra-group analysis (p0.05). @*Conclusion@#These results showed that the motor inhibition response could be learned through a stop-signal task. Moreover, these findings suggest that actual practice is a more effective method for learning the motor inhibition response.

Motor Skill Learning on the Ipsi-Lateral Upper Extremity to the Damaged Hemisphere in Stroke Patients

PURPOSE: This study examined whether there is a difference in motor learning through short-term repetitive movement practice in stroke survivors with a unilateral brain injury compared to normal elderly participants. METHODS: Twenty-six subjects who were divided into a stroke group (n=13) or sex-aged matched normal elder group (n=13) participated in this study. To evaluate the effects of motor learning, the participants conducted a tracking task for visuomotor coordination. The accuracy index was calculated for each trial. Both groups received repetitive tracking task training of metacarpophalangeal joint for 50 trials. The stroke group performed a tracking task in the upper extremity insi-lesional to the damaged hemisphere, and the normal elder group performed the upper extremity matched for the same side. RESULTS: Two-way repetitive ANOVA revealed a significant difference in the interactions (time×group) and time effects. These results indicated that the motor skill improved in both the stroke and normal elder group with a tracking task. On the other hand, the stroke group showed lesser motor learning skill than the normal elder group, in comparison with the amount of motor learning improvement. CONCLUSION: These results provide novel evidence that stroke survivors with unilateral brain damage might have difficulty in performing ipsilateral movement as well as in motor learning with the ipsilateral upper limb, compared to normal elderly participants.

Effects of Virtual Reality Horse Riding Simulator Training Using a Head-Mounted Display on Balance and Gait Functions in Children with Cerebral Palsy: A Preliminary Pilot Study

PURPOSE: The purpose of this study was to investigate the effects of three-dimensional virtual reality horse riding simulator training using a head-mounted display on gait and balance in children with cerebral palsy.METHODS: Ten children with cerebral palsy were randomly assigned to the horse riding simulator (HRS) group (n=5) or the horse riding simulator with virtual reality (HRSVR) group (n=5). To evaluate balance, center of gravity (COG) sway velocity and total sway distance of each group were assessed using the Wii balance board, and gait speed and stride length of each group were assessed using a gait analysis system.RESULTS: Intra-group comparisons between pre- and post-intervention measures revealed that there were significant changes in all gait and balance variables such as stride length, gait velocity, COG sway velocity and COG sway distance in the HRSVR group (p<0.05). In the HRS group, there were significant changes in all variables except stride length (p<0.05). In addition, inter-group comparisons showed significant differences between the two groups in stride length, gait velocity and COG sway distance except COG sway velocity (p<0.05).CONCLUSION: The findings of this study suggest that horse riding simulator training combined with 3D virtual reality can be a new positive therapeutic approach for improving functional performance in children with cerebral palsy.

Effects of Backward Walking Training with Task Orientation on the Functional Gait of Children with Spastic Hemiplegia

PURPOSE: This study examined the effects of backward walking training with task orientation on the functional walking ability of children with cerebral palsy.METHODS: This study was a single-blinded, randomized controlled trial with a crossover design conducted at a single rehabilitation facility with cross-over to the other intervention arm following a two-week break. For a total of 12 children with spastic hemiplegia cerebral palsy, the forward walking training group (n=6) underwent training three times a week for three weeks, 40 minutes a day, and the backward walking training group (n=6) was also trained under the same conditions. To identify the functional walking ability, variables, such as the walking speed, stride length, and step length, were measured using a walk analyzer (OptoGait, Microgate S.r.l, Italy).RESULTS: Both groups showed significant increases in walking speed, stride length, and step length (p<0.01). The backward walking group showed more significant improvement in the walking speed from pre- to post-test (p<0.05). The gait characteristics were similar in the two groups (stride length and step length) but the walking speed in the backward walking group showed a mean difference between the positive effects higher than the forward walking group.CONCLUSION: Task-oriented backward walking training, which was conducted on the ground, may be a more effective treatment approach for improving the walking functions of spastic hemiplegia children than forward walk training.

The Adverse Effect of Proprioceptive Sense in Head-Neck according to Smartphone Usage

PURPOSE: Most studies have reported pain in the head-neck and upper-limbs according to smartphone usage, which is related to the proprioception sense in the head and neck, but there have been few studies. Therefore, the aim of this study was identify the adverse effects of the proprioceptive sense in the head-neck according to smartphone usage. METHODS: Twenty-seven young adults (male: 9, female: 18) were enrolled in this study. The proprioceptive sense was measured through the joint reposition sense error and neural positon error in the head-neck during smartphone usage for 0, 5, and 20 minutes. The Noraxon MyoMotion system was used to record the joint position angle and neutral positon in the head-neck. One-way repeated ANOVA was used to identify the differences between the three smartphone use durations and the least-squares difference was used as a post hoc test. The data were analyzed using SPSS 18.0 software. RESULTS: The joint reposition sense error and neural positon error in the head-neck were significantly different among the 0, 5, and 20 minutes of smartphone usage (p < 0.05). In the post hoc test, the joint reposition sense error and neural positon error showed a significant difference between smartphone use for 0 minute and 5 minute, and between smartphone use for 0 minute and 20 minutes. CONCLUSION: This study suggests that smartphone use within 5 minutes can have adverse effects on the proprioceptive sense. Therefore, it is necessary to consider the appropriate use time and break time when using smart phones.

Immediate Effect of Postural Control of the Contra-Lateral Side on Exercise-Induced Fatigue of the Ipsi-Lateral Plantar Flexor Muscle

PURPOSE: The purpose of the current study was to examine the effects of exercise-induced fatigue of the plantar flexor muscle in the dominant ankle on the plantar flexor strength and postural control function of the contra-lateral side. METHODS: Twenty-one young adults (male: 10, female: 11) volunteered to participate in this study. An exercise-induced fatigue protocol to induce fatigue was performed in the plantar flexor of the dominant ankle. For the fatigue protocol, the participants were instructed to raise their heels as high as possible in the position with one leg stance of the dominant lower limb, and the heel was then downed after holding for 1 second. The muscle strength of the contra-lateral plantar flexor was measured using a digital muscle strength test device, and the static and dynamic postural control were tested by acquiring the center of gravity velocity while performing one leg standing. A paired t-test was used to identify the differences between the pre- and post, and the data were analyzed using SPSS 12.0 software. RESULTS: Comparison of the pre- and post-test data revealed a significant difference in the plantar flexor strength and dynamic postural control after exercise-induced muscle fatigue in the dominant side. On the other hand, there was no significant difference in the static postural control. CONCLUSION: These findings have practical implications, suggesting that unilateral muscle fatigue affects the ankle muscle strength and postural ability of the contralateral side.

Relationship between Ipsilateral Motor Deficits on the Less-Affected Side and Motor Function Stage on the Affected Side

PURPOSE: Aim of this study was to investigate whether there are ipsilateral motor deficits for visuospatial accuracy and fine movements by making a comparison between stroke patients and healthy subjects. We examined whether ipsilateral motor deficits are influenced by the level of functional movements and muscle strength of the upper and lower extremities of the affected side. METHODS: Thirty post-stroke subjects and 20 normal aged matched subjects were recruited. Outcome measures for less-affected side were the tracking task and nine-hole pegboard test. Fugl-Meyer test and motricity index were applied for the measurement of functional movements and muscle strength of affected side. RESULTS: Tracking task and nine-hole pegboard test was significantly different between control and experimental group. In terms of accuracy index according to tracking, the experimental group showed a lower accuracy index in the MCP joint than the control group. However, there were no significant difference relation between the level of motor function of the affected side and the motor deficit level of ipsilateral side. CONCLUSION: Ipsilateral motor deficits may have significant clinical implications. It needs to be noted that although many patients, families, and medical staff are focused only on motor deficits of the affected side, motor deficits of the sound side can cause difficulties in daily living movements requiring delicate movements. In addition, there was no significant correlation between the level of motor function of the affected side and motor deficits of the sound side.

Neck Pain in Adults with Forward Head Posture: Effects of Craniovertebral Angle and Cervical Range of Motion

OBJECTIVES: The purpose of this study was to determine whether the cranial vertebral angle (CVA) and the range of motion (ROM) was different between participants with a forward head posture (FHP), with or without pain. METHODS: Forty-four participants who had FHP participated in this study. The FHP was assessed digitally by measuring a lateral view the CVA for each subject. A cervical ROM device measured the cervical ROM. The volunteers were allocated to either, with pain (n = 22), or without pain (n = 22) groups, and pain was evaluated using the Numeric Pain Rating Scale. RESULTS: The FHP in the pain group showed a significant difference in the CVA, and the cervical ROM in both flexion and extension, compared with those in the FHP without pain group (p < 0.05). Logistic regression analysis indicated that the occurrence of cervical area pain was higher amongst subjects who had a decreased CVA and flexion motion. CONCLUSION: This study suggested that decreased CVA and cervical flexion range, were predictive factors for the occurrence of pain in the cervical region.

The Effect of Chair Backrest on Respiratory Function in Prolonged Sitting Position

PURPOSE: The purpose of this study was to determine the effects of a chair backrest on respiratory function after prolonged sitting. METHODS: Twenty-four young healthy subjects (12 males and 12 females) volunteered to participate in this study, and were equally allocated to a backrest (n=12) or a without backrest group (n=12). A spirometer was used to measure the respiratory functions of all subjects. RESULTS: The chair with backrest group were significant difference in forced vital capacity (FVC), Forced expiratory volume in 1 second (FEV1), and peak expiratory flow (PEF) after sitting for 1 hour, compared with chair without backrest group (p < 0.05). The chair with backrest group showed a significantly decreased in FVC, FEV1, and PEF. CONCLUSION: Using a chair without a backrest may help to reduce lung function deterioration as compared with a chair with a backrest.

Research on the Quality of Life of the Parents by Functions, Activities, Participation, and Environmental Factors of Children with Cerebral Palsy Using ICF-CY Checklist

PURPOSE: This study examined whether the quality of life of parents of children with cerebral palsy is affected by the functions, activities, participation, and environmental factors using an ICF-CY check list. METHODS: This study recruited in 26 parents of children with cerebral palsy. The functions, activities, participation, and environmental factors of the children were evaluated using ICF-CY checklist. To measure the quality of life of parents, this study used world health organization quality of life (WHOQOL-BREF), which was composed of a total of 26 questions. The GMFCS (gross motor function classification system) was used to assess the degree of disability in the children. Multiple regression analysis was performed to examine the effects of the ICF-CY checklist on the quality of life. Correlation analysis was performed to examine the correlation between GMFCS and WHOQOL. RESULTS: The functions, activities, participation, and environmental factors were significantly different from WHOQOL-BREF. On the other hand, the contextual factor showed a significant difference in the neuromusculoskeletal and movement-related functions (b7), and service, systems, and policies (e5)(p < 0.05). CONCLUSION: This study suggests that the functions and environmental factors affect the quality of life of parents of children with cerebral palsy. Therefore, these findings suggest that contextual factors, such as neuromusculoskeletal and movement-related functions (b7), and service, systems and policies (e5), which can be facilitators, should be considered for improving the quality of life of parents of children with cerebral palsy.

The Circadian Effects on Postural Stability in Young Adults

PURPOSE: Few studies have addressed the effect of diurnal circadian rhythms on postural stability, and thus the aim of the present study was to examine circadian effects on static and dynamic postural stability in young adults. METHODS: Twenty-four subjects (9 men, 11 women: age=22.20±1.77, height=167.20±10.47, weight=59.85±10.66) from a university community volunteered for this study. Static and dynamic balance testing, which recorded using a Good Balance system (Good Balance, Metitur Ltd, Finland) was conducted at 9:00, 13:00, and 17:00 hours on two consecutive days, and the sequencing of static and dynamic balance tests were randomized. Results were analyzed using the non-parametric one-way repeated Friedman test in SPSS version 18.0 (SPSS Inc., Chicago, IL, USA), and variable found to be significant were subjected to Wilcoxon post hoc testing. RESULTS: Static and dynamic balance showed significant difference at the three times assessments (test at 9:00, 13:00, and 17:00) during circadian. In the post hoc test of static (anteroposterior distance, mediolateral distance and COP (center of pressure) velocity) and dynamic balance (performance time), 13:00 was the longer and faster than 9:00. CONCLUSION: These results indicated that control of postural balance is influenced by diurnal circadian rhythms, and confirm that control of postural balance is more effective and better performance in the 09:00 hours than 13:00 hours or 17:00 hours.

Effect of Action Observation Training with Auditory Feedback for Gait Function of Stroke Patients with Hemiparesis

PURPOSE: Previous studies have reported that action observation training has beneficial effects on enhancing the motor task, such as balance and gait functions. On the other hand, there have been few studies combined with action observation training and auditory feedback. The purpose of this study was to determine the effects of action observation training with auditory feedback on the gait function in stroke patients with hemiparesis. METHODS: A total of 24 inpatients with post-stroke hemiparesis were assigned randomly to either an experimental group 1 (EG 1, n=8), experiment group 2 (EG 2, n=8), control group (CG, n=8, EG 1). The EG 2 and CG watched video clip demonstrating three functional walking tasks with auditory feedback, without auditory feedback, and showing a landscape image, respectively. The exercise program consisted of 30 minutes, five times a week, for four weeks. The participants were measured to 10MWT (10 m walk test), 6MWT (6 minutes walking distance test), TUG (timed up and go test), DGI (dynamic gait index), time and steps of F8WT (figure-of-8 walk test). RESULTS: In the intra-group comparison after the intervention, EG 1 and EG 2 showed a significantly different gait function (10MWT, 6MWT, DGI, TUG, F8WT) (p < 0.05). In the inter-group comparison after intervention, EG 1 showed significant improvements in the entire gait parameters and EG 2 only showed significant improvement in DGI and TUG compared to CG (p < 0.05). CONCLUSION: These findings show that action observation training with auditory feedback may be used beneficially for improving the gait function of stroke patients with hemiparesis.