• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.22 no.2
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• pp.57-63
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• 2016

Background: Instability due to ankle sprains will be accompanied by a problem of balance and pain change. Balance trainer is used to improve the ankle strength and balance ability. The purpose of this study was to evaluate the change of pain and postural balance ability in ankle joint after balance trainer application in patients with ankle sprain and instability. Methods: Twenty patients in K hospital in Incheon were enrolled. Balance trainer was applied to 10 subjects in the experimental group and 10 subjects in the Balance cushion under the same conditions as the experimental group to compare the pain and balance ability. Results: In the experimental group, there was a significant difference in the change of the pain variation. In the postural balance ability comparison, there was a significant difference in total and post - posterior comparison compared to the control, but there was no significant difference in the postural balance ability comparison. Conclusion: Pain and postural balance ability of patients with instability due to ankle sprain improved the pain and balance ability of the Balance trainer group compared to the Balance cushion training group.

• Journal of the Korean Society of Physical Medicine
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• v.9 no.3
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• pp.255-262
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• 2014

PURPOSE: This study was to investigate the effectiveness of TENS on balance in stroke patients by analyzing some components such as foot pressure, limit of stability and velocity sway after providing somatosensroy input using TENS. METHODS: Twenty five subjects participated and were randomly divided into two groups, TENS group (n=13) and control group (n=12) by the computer program. Interventions were given to subjects 5 days a week for four weeks. TENS group were treated with TENS for 60 minutes in addition to the conventional therapy which included 30-minute exercise and rehabilitation ergometer training for 15 minutes. Control group performed only conventional therapy. TENS was applied on the skin of soleus, tibialis anterior, tensor fascia latae and vastus medialis in affected side. Foot pressure, limit of stability and velocity sway for balance test were measured using Biorescue. RESULTS: TENS group was significantly increased limit of stability and foot pressure in affected side more than control group. And in eye closed condition, TENS group was significantly decreased velocity sway more than control group. CONCLUSION: The application of TENS is effective to improve the somatosensory input of affected side and to increase the motor function and balance ability.

• Journal of the Korean Institute of Intelligent Systems
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• v.16 no.5
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• pp.601-607
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• 2006

This paper proposes a novel balance control scheme of a biped robot to predict the next position of ZMP using Kalman Filter. The mathematical model of the biped robot is generally approximated by 3D-LIPM(3D-Linear Inverted Pendulum Mode), but it cannot completely express the robot's dynamics. The stability of the biped robot depends on whether the ZMP(Zero Moment Point) position is in the stability region or out of. And the internal error between the robot mechanism and its model could affect the stability of a robot. Therefore, the proposed balance control not reduces the internal error, but also timely generates the proper control. The experiment of the proposed balance control is simulated on the virtual workspace where the biped robot may encounter with various difficulties.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.11a
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• pp.531-536
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• 2006

In four cylinder engine, the second order inertia force occurs due to the reciprocating parts of the cylinder. Because the magnitude of the inertia force is proportional to a square of the angular velocity of crank shaft, engine gets suffered from vibration excited by unbalanced inertia force in high speed. This vibration excited by the unbalanced inertia force can be canceled by applying a balance shaft. Balance shaft has one or more unbalance mass and rotates twice quickly than the crank shaft. In this paper, an unbalanced force caused by the rotating of unbalance mass of balance shafts was calculated. The directional equivalent stiffness and damping coefficients of the journal bearing of balance shafts was calculated. Equations of rotational vibration modes were derived using directional stiffness and damping coefficients. The dynamic stability of balance shafts was analyzed and evaluated for two type models using the equivalent stiffness and damping coefficients. An efficient procedure to he able to evaluate dynamic stability and design optimal balance shaft was proposed.

• Physical Therapy Korea
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• v.6 no.3
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• pp.11-21
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• 1999

Human balance is maintained through a complex process involving sensory detection of body motions, integration of sensorimotor information within the central nervous system, and execution of appropriate musculoskeletal responses. The basic task of balance is to position the body center of gravity (COG) over some portion of the support base. When the COG extends beyond the base of support, the person has exceeded the limits of stability (LOS). At this point, a step or stumble is required to prevent a fall. Automatic postural responses operate to keep the COG over the base of support. They are a set of functionally organized, long-loop responses that act to keep the body in a state of equilibrium. There are four commonly identified automatic postural responses, or strategies. These are ankle strategy, hip strategy, suspensory (knee) strategy, and stepping strategy. Thus, the purpose of this study was to evaluate the LOS using various knee strategies. Forty subjects participated in this study. The subjects were comprised of 20 males and 20 females who were without neurologic, orthopaedic or balance performance impairments. The LOS was measured with a Balance Performance Monitor (BPM) Dataprint Software Version 5.3. The results of this study were as follows: 1) Knee joint angle which is to increase stability of standing balance with using knee strategy was at mid-range. 2) There were statistically significant differences in anteroposterior LOSs according to the knee strategy. 3) There were no statistically significant differences in mediolateral LOSs according to the knee strategy. 4) There were statistically significant differences of anteroposterior LOSs with using knee strategy according to gender. 5) There were no statistically significant differences in mediolateral LOSs with using knee strategy according to gender.

• The Journal of Korean Physical Therapy
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• v.32 no.4
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• pp.203-209
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• 2020

Purpose: This study examined the effects of a physical stability exercise program on the functional movement and balance of middle school volleyball players to provide future management and training data to improve the performance of volleyball players. Methods: The subjects were 20 volleyball players from Y Middle School in Mokpo. The results of comparing and analyzing the effects of the physical stability exercise program on the functional movement and balance of middle school volleyball players for 10 weeks are as follows. Results: The number of participants who showed power and agility (p<0.01) was increased significantly, and the response time was shortened significantly (p<0.01). On the evaluation of functional movement, the total score showed a significant difference between the pre-test at 10.90±1.30 points and the post-test at 13.81±.60 (p<0.001). The subjects' balance showed a significant difference from 84.11±7.53 to 97.65±8.47 (p<0.001), and the Right Composite Score showed a significant difference from 83.74±6.64 to 97.27±8.48 (p<0.001). Conclusion: The application of a physical stability exercise program for 10 weeks is effective in improving the speed, agility, functional movement, and balance to volleyball players who are weakened and at risk of injury. This is believed to prevent or reduce injury.

• Journal of the Korean Society of Physical Medicine
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• v.9 no.3
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• pp.263-270
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• 2014

PURPOSE: The purpose of this study was to examine the immediate changes in the weight-bearing ankle dorsiflexion range of motion (ROM) and the dynamic balance in asymptomatic subjects using the modified Star Excursion Balance Test (SEBT) after ankle balance taping (ABT) and placebo ABT with kinesiology tape METHODS: A total of 23 active participants (11 men, 12 women) volunteered for this study. Ankle flexibility was assessed using the weight-bearing lunge test, and dynamic balance was assessed using the modified SEBT. Participants were asked to respond to questions regarding their perception of stability, reassurance, and confidence when performing modified SEBT. RESULTS: The weight-bearing ankle dorsiflexion ROM did not show a significant decrease after real ABT or placebo ABT compared to the ROM prior to ABT. The anterior, posterolateral, and posteromedial reach distances of SEBT did not increase significantly after real ABT or placebo ABT compared to the distances prior to ABT. However, the participants' perception of stability, reassurance, and confidence, when performing SEBT with real ABT, was increased compared to that during the control trial. CONCLUSION: This study showed that although real ABT did not immediately improve the reach distances in the 3 directions during modified SEBT, it improved the participants' perception of stability, reassurance, and confidence without decreasing weight-bearing ankle dorsiflexion ROM.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.6
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• pp.150-157
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• 2019

The purpose of this study was investigate the effect of gastrocnemius(GCM) muscle length on the dynamic balance and antero-posterior pressure distribution of foot. Thirty subjects were recruited and each subject was classified with control experimental and control group according to GCM muscle length. The experimental group included subjects with shortness of GCM muscle length, the control group included subjects with normal length of GCM. The dynamic balance and antero-posterior pressure distribution of foot were measured by Biorescue equipment. To evaluate dynamic balance, we collected data of limit of stability in antero-posterior direction. We analyzed the data by using independent t-test. The alpha level was set 0.05. The results showed that the dynamic balance and antero-posterior pressure distribution of foot were significantly different between two groups (p<0.05). This study suggests that the shortness of GCM affects anterior limited of stability in dynamic balance and anterior pressure distribution of foot. Therefore, it is important to maintain optimal GCM muscle length for normal balance ability and prevention of musculoskeletal disease.

• Journal of Korean Physical Therapy Science
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• v.15 no.1
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• pp.67-74
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• 2008

A decrease in the ability to maintain static and dynamic balance after stroke could be related to the inability to select reliable sensory information in producing relative motor action needed to maintain postural stability. The purpose of this study was to compare the effects of two different types of surface conditions on the balancing ability of subjects with stroke. Eighteen hemiparetic subjects were assigned to an experimental and control group participating in a six－week rehabilitative therapeutic exercise program focusing on balance and mobility. Exercises were performed 3 to 5 times per week in a stable surface condition by the control group, and in an unstable surface condition by the experimental group. Pre－ and post test assessments involved the measurement of the static balance and dynamic balance, respectively by 7－item Berg Balance Scale－3P and by Pro－3 Balance System. Results showed that under the unstable surface condition, static balance in the experimental group showed more improvement than that of the control group.(Statistically, not very significant.) All the aspects of dynamic balance and mediolateral sway(balance) improved significantly than those of the control group. However, there were no significant differences between two groups. Overall, it can be concluded that under the unstable surface condition, the rehabilitative therapeutic exercise programs are effective in improving the dynamic balance of stroke subjects. The results suggest that the adaptation of the unstable surface in the rehabilitative therapeutic exercises could be effective for the patients with hemiplegia in balance. Further studies are needed to confirm the effectiveness of the unstable surface on improving balance and postural stability of hemiplegics.

• Journal of the Ergonomics Society of Korea
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• v.31 no.2
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• pp.337-343
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• 2012

Objective: The aim of this study was to determine the effect of abdominal-compression belt in one leg standing on balance in normal adult. Background: With the effects of increased intra-abdominal pressure, the abdominal-compression belt is contributing to a static balance control. However, specific study is still insufficient. Method: Forty subjects were randomly allocated to two groups: control(n=20) and experimental group(n=20), respectively. The experimental group used an abdominal-compression belt, whereas the control group did not that. All subjects were educated using pressure biofeedback unit and ultrasound imaging for exact application by abdominal-compression belt. Main outcome measurement was used a general stability index, fourier harmony index, weight distribution index, and fall index in tetrax balance system. Results: Experimental group improved significantly on general stability, only 2 factors(eyes closed with head turned forward and eyes closed with head turned backward) among fourier harmony index, and fall index, However, weight distribution index did not revealed significant difference. Conclusion: The findings suggest that application of abdominal-compression belt could be effective on improving balance ability in one leg standing of normal adults. Application: The results of the abdominal-compression belt might help to control balance in workers.