• PNF and Movement
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• v.6 no.1
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• pp.1-12
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• 2008

Purpose : The purpose of this study was to investigate the effects of the combined patterns of PNF(proprioceptive neuromuscular facilitation) on the static balance ability. Methods : The measurements of the static balance ability were completed by 10 subjects for 6 weeks, from October to November 2007. The combined patterns of PNF were carried out by means of self-exercising suggested by Dietz, which were designed as four cases: two positions (standing and quadruped) for both patterns(sprinter and skater), respectively. The exercises were practiced once a day, 3 times a week in same condition. By using the GOOD BALANCE system, assessment of the static balance ability was taken at before and after exercise from 6 positions: normal standing, one leg left and one leg right standing when eye open and close, respectively. For each case, the experimental data was obtained in 3 items: mean X speed, mean Y speed and velocity moment. Results : The results of this study were as follows : 1. There were statistically significant differences of Mean X speed, Mean Y speed and Velocity moment between the before and the after exercise in the case of normal standing when eye open and close(NSEO and NSEC), respectively. 2. There was statistically significant difference of Mean X speed between the before and the after exercise in the case of one leg left standing when eye open(OLLEO). In this case, however, the statistically significant differences were not found in both terms of Mean Y speed and Velocity moment. 3. There were statistically significant differences of Mean X speed and Mean Y speed between the before and the after exercise in the case of one leg left standing when eye close(OLLEC). In this case, however, the statistically significant difference was not found in term of Velocity moment. 4. There were statistically significant differences of Mean X speed, Mean Y speed and Velocity moment between the before and the after exercise in the case of one leg right standing when eye close(OLREC). 5. There was statistically significant difference of Mean X speed between the before and the after exercise in the case of one leg right standing when eye open(OLREO). In this case, however, the statistically significant differences were not found in both terms of Mean Y speed and Velocity moment. 6. There were statistically significant differences of total Mean X speed, total Mean Y speed and total Velocity moment between the before and the after exercise. Conclusions : The above results from this study indicated that the combined patterns of PNF have improved the static balance ability. However the used self-exercise can be applied to normal people, i.e., the exercise is difficult to apply into clinical patients. The further study should be focused at development of various modified forms of the combined patterns of PNF in keeping up the improvement effect of this exercise.

• Physical Therapy Korea
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• v.5 no.4
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• pp.41-51
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• 1998

The right hip abductor musculature has been reported to demonstrate "stretch weakness" attributable to chronic elongation imposed by standing posture common to right-handed healthy persons. Kendall and associates have described the concept of "stretch weakness",. The purpose of this study was to assess isometric hip abduction torque and surface electromyographic activity (using MYOMED 432) in a sample of 40 healthy right-handed persons (20 male, 20 female), all of whom agreed to participate in the study, and compare side difference in the hip abductor musculature. In order to assure the statistical significance of the results, the paired t test was applied at the .05 level of significance. The results were as follows: 1) The difference in apparent leg length of right and left legs was significant at the .05 level. 2) There was a significant difference between right and left pelvic height (standing position) at the 05 level measurements, and scapula height at the .05 level. 3) Power measurements and action potentials of right hip abductor were greater than the left hip abductor regardless of the range of joint motion (inner range, outer range) 4) The difference in muscle power and action potentials according to inner or outer range of both hip abductor were significant at the .05 level. 5) In supine during active left hip abduction, the appearance of action potentials in the right hip abductors is indicative of contra-lateral effect (p<.05) These results suggest: In healthy right-handed persons, the apparent leg length on the right is longer than on the left, and pelvic height is elevated on the right side. Muscle those and muscle action potentials of the right hip abductor are higher than those of the left hip abductor in the lengthened position. Therefore, the results in this study are contrary to Kendall's. This type of study should be carried out in many physical therapy departments.

• The Journal of Korean Physical Therapy
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• v.2 no.1
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• pp.35-46
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• 1990

The right hip adbuctor musculature has been reported to demonstrate 'stretch weakness' attributable to chronic elongation imposed by standing posture common to right-handed healthy persons. Kendall and associates have described the concept of 'stretch weakness'. The purpose of this study was to assess isometric hip abduction torque and surface electro-myographic activity (using MYOMED 432) in a sample of 40 healthy right-handed persons (20 male, 20 female), all of whom agreed to participate in the study, and compare side difference in the hip abductor musculature. In order to assure the statistical significance of the results, the paired t-test was applied at the .05 level of significance. The results were as follows : 1. The difference in apparent leg length of right and left legs was significant at the .05 leve1. 2. There was a significant difference between right and left pelvic height (standing position) at the .005 level measurements, and scapula height at the .05 level. 3. Power measurements and action potentials of right hip adbuctor were greater than the left hip adbuctor regardless of the range of joint motion (inner range, outer range). 4. The difference in muscle power and action potentials according to inner or outer range of both hip abductor were significant at the .05 level. 5. In supine during active left hip abduction, the appearance of action potentials in the right hip abductors is indicative of contra-lateral effect (p<.005). These results suggest : In healthy right-handed persons. the apparent leg length on the right is longer than on the left, and pelvic height is elevated on the right side. Muscle torque and muscle action potentials of the right hip adbuctor art higher than those of the hip abductor in the lengthened position. Therefore, the results in this study are contrary to Kendall's. This type of study should be carried out in many physical therapy departments.

• The Journal of Korean Physical Therapy
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• v.14 no.3
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• pp.203-225
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• 2002

An excessive Q-angle has been implicated in the development of knee injuries by altering the lower-extremity locomotion kinematics. The purpose of this study was performed to examine the correlation between the Q-angle and the CTA during pronation and supination of the foot in the standing status. The participants of this examination were 60 adult(30 men and 30 women) who had no orthopaedic and neurological impairment, aged between 20 and 40years. The foot tilt(FT1)is made of acrylic plate and the slope of the surface is altered as $0^{\circ}$ pronation$(10^{\circ},\;20^{\circ},\;30^{\circ})$ and supination $(10^{\circ},\;20^{\circ},\;30^{\circ})$. The results were as follows : 1. The result about the Q-angle and the CTA by comparing pronation and supination of the foot There was statistical significance difference in the left /right Q-angle and the left/right CTA with pronation and supination of the foot(P<0.05). 2. The result about correlation in the left /right lower-extremity There were positive correlation between the right Q-angle and the right CTA and negative correlation except the supination$(30^{\circ})$ between the left Q-angle and the left CTA.

• Physical Therapy Rehabilitation Science
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• v.8 no.1
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• pp.40-44
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• 2019

Objective: The purpose of this study was to examine the changes in postural stability according to ankle fixation in healthy university students. Design: Cross-sectional study. Methods: Thirty healthy subjects (15 males and 15 females, 20.13 years, 167.49 cm, 65.87 kg) were recruited on a voluntary basis. The BT4 system (HUR Laps Oy, Tampere, Finland) was used to measure the static (standing posture with eyes open and eyes closed) and dynamic (external perturbation and limits of stability (LOS) in the forward, backward, left, and right side) balance abilities. External perturbation was measured by the subject's postural sway velocity and area for 20 seconds after being impacted by a gym ball. Static and dynamic stabilities were measured with ankle joint fixation and non-fixation conditions. Ankle fixation was provided using Mueller tape on both ankle joints. Results: For static stability under the standing posture, there was no significant difference between standing with ankle joint fixation and non-fixation conditions. However, dynamic stability (external perturbation and LOS in the forward, backward, left, and right side) was significantly higher in the standing with the non-fixation condition compared to the standing with ankle joint fixation condition (p<0.05). Conclusions: Our results reveal that ankle joint fixation can influence dynamic stability during standing. Thus, we believe that this result provides basic information for making improvements in postural control and may be useful in balance training for fall prevention.

• Physical Therapy Rehabilitation Science
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• v.5 no.1
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• pp.15-21
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• 2016

Objective: The purpose of this study was to see the changes in muscle activity of the upper limb in persons using a smartphone. Design: Cross-sectional study. Methods: An experiment was conducted to target 15 right-handed university students. Experiments were carried out for students using cell phones for more than a year. In this study, experiments were carried out with one-handed and both handed operation of smartphone use in a sitting position, the same parameters with smartphone use in a standing position. The experiments were carried out by having the subjects write a text message in Korean on the smartphone for 3 minutes repeated 3 times with a rest period of 10 seconds given between each 3 minute period. Electromyography (EMG) was used to record the muscle activity of the upper trapezius (UT), extensor carpi radialis (ECR), and abductor pollicis (AP) during phone operation. Results: The muscle activity of the AP and ECR were significantly higher during single handed compared to double handed in both sitting and standing position (p<0.05). The muscle activity of the ECR was significantly higher in standing position compared to sitting position with double handed use of the smartphone (p<0.05). UT muscle activity of the right has been activated more than twice compared to the left UT in a sitting position (p<0.05). And UT muscle activity on the right has been activated more than five times compared to the left in a standing position (p<0.05). Conclusions: Using smartphone with double hand is useful for the prevention of musculoskeletal disorders.

• Physical Therapy Korea
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• v.19 no.4
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• pp.24-31
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• 2012

The aim of this study was to investigate the effectiveness of self-stretching exercises for iliotibial band (ITB) (Side-lying; right hip and knee were flexed to support the pelvis while left hip was extended and adducted, Standing A; side-bending of the trunk on standing with crossed leg, Standing B; same as Standing A, except the hands were clasped overhead and shifted right side, and Standing C; same as Standing B, except moving the arms diagonally downward) to help determine the most effective self-stretching method to stretch ITB. Twenty-one healthy subjects who do not have ITB shortness from Yonsei University (14 men and 7 women) between the ages of 18 to 28 years voluntarily participated. Ultrasound was performed to measure the thickness of the ITB between the long axis of the ITB and the level parallel to the lateral femoral epicondyle during four self-stretching exercises. All data were found to approximate a normal distribution. We used a one-way repeated-measures analysis of variance (ANOVA) to compare the thickness of the ITB among all self-stretching exercises. The level of significance was set at ${\alpha}$=.05. The ANOVA was followed by Bonferroni's correction. The overall mean of ITB thickness was $1.14{\pm}.4$ mm (${\pm}$ standard deviation) in resting status. The change in the ITB thickness in percentages between the tested position of each self-stretching exercises and resting status was significant (p<.05) (Side-lying $26.62{\pm}10.18%$ with 95% confidence interval [CI]=21.99~31.25%; Standing A $29.46{\pm}16.19%$ with 95% CI=22.09~36.84%; Standing B $44.06{\pm}14.82%$ with 95% CI=37.31~50.81%; Standing C $53.76{\pm}12.1%$ with 95% CI=48.25~59.29%). Results indicated significant differences among four self-stretching exercises except Side-lying versus Standing A (p<.01). Based on these findings, the Standing C self-stretching exercise was the most effective in stretching the ITB thickness among four types of ITB self-stretching exercises. Additionally, the Side-lying self-stretching exercise using gravity to stretch the ITB is recommended as a low-load (low-intensity), long-duration stretch.

• Journal of the Ergonomics Society of Korea
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• v.29 no.3
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• pp.279-286
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• 2010

The purpose of this study was to compare the electromyographic(EMG) activities of trunk and hip muscles between right and left sides while subjects performed prolonged manual task in asymmetric and symmetric weight-bearing posture. Fifteen healthy male college students were recruited for this study. The subjects were asked to perform bimanual upper extremity task for 6 minutes in two different standing postures. In the symmetric weight-bearing posture, the subjects were standing with evenly distributed body weights to both legs. In the asymmetric weight-bearing posture, the subjects distributed about 90% of their body weight onto their preferred(supporting) leg and 10% of their body weight onto the opposite leg while they were standing. EMG activities of the right and left internal oblique, erector spinae, gluteus maximus, and gluteus medius were measured and normalized as % MVIC. Then the EMG data were statistically analyzed using paired t-tests. The EMG activities of all measured muscles were not significantly different between the right and left side in the symmetrical weight-bearing posture(p>0.05). However, the EMG of the supporting side internal oblique was significantly lower than the opposite side(p<0.05), and the EMG of the erector spinae, gluteus maximus, and gluteus medius were significantly greater on the supporting side(p<0.05). The results of this study support that unbalanced use of right and left muscle possibly causes the changes in muscle length which results in asymmetry of trunk and hip muscles. Furthermore, the uneven weight support onto right and left legs will cause a distortion of viscoelastic ligaments around hip and sacroiliac joints in the long run. Further studies to determine the effect of various manual tasks on the trunk and hip muscles as well as the effect of asymmetrical weight-bearing standing posture on hip and back muscle fatigue may be required.

• Journal of Bone Metabolism
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• v.25 no.4
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• pp.243-249
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• 2018

Background: The aim of this study was to determine the accuracy and error range of hand grip strength measurement using various methods. Methods: Methods used for measurement of hand grip strength in 34 epidemiologic studies on sarcopenia were analyzed. Maximum grip strength was measured in a sitting position with the elbow flexed at 90 degrees, the shoulder in 0 degrees flexion, and the wrist in neutral position (0 degrees). Maximum grip strength in standing position was measured with the shoulder in 180 degrees flexion, the elbow fully extended, and the wrist in neutral position (0 degrees). Three measurements were taken on each side at 30 sec intervals. The uncertainty of measurement was calculated. Results: The combined uncertainty in sitting position on the right and left sides was 1.14% and 0.38%, respectively, and the combined uncertainty in standing position on the right and left sides was 0.35 and 1.20, respectively. The expanded uncertainty in sitting position on the right and left sides was 2.28 and 0.79, respectively, and the expanded uncertainty in standing position on the right and left sides was 0.71 and 2.41, respectively (k=2). Conclusions: Uncertainty of hand grip strength measurement was identified in this study, and a significant difference was observed between measurement. For more precise diagnosis of sarcopenia, dynamometers need to be corrected to overcome uncertainty.

• Korean Journal of Applied Biomechanics
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• v.32 no.3
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• pp.80-86
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• 2022

Objective: The purpose of this study was to investigate the effects of three rotational jump conditions (standing jump, left rotational jump and right rotational jump) on stability through center of pressure (COP) and EMG variables analysis. Method: A total of 16 college students (age: 24.13 ± 7.17 years, height: 169.24 ± 8.23 cm, weight: 65.65 ± 13.88 kg) participated in this study. The study used wireless two COP plates and wireless eight channel EMG. The analyized variables were 11 variables for COP and RMS for EMG, which were analyzed using one-way analysis of variance with repeated measures according to three rotational jump conditions. Results: Among the COP variables, left rotational jump (LRJ) and right rotational jump (RRJ) were larger than standing jump (SJ) for left and right amplitude, area, total displacement, and average velocity for both feet among the variables of COP, and for area of the left foot, RRJ was larger than that of SJ. Among the EMG variables, there was no statistical difference between the muscle activations, but the muscle activity was significantly higher in the order of RRJ, LRJ, and SJ according to direction of rotation. Conclusion: Although the results of COP and EMG were not consistent through this study, it can be expected that the differences in COP was due to the amount of rotation during rotational jump-landing in the left and right directions, and that the EMG is determined by the lateral movements required for rotation.