• Korean Journal of Applied Biomechanics
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• v.28 no.1
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• pp.1-8
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• 2018

Objective: The purpose of this study is to investigate the differences in biomechanical variables of golf driving motion according to gender. Method: A total of 21 healthy golfers (11 men and 10 women) who have more than 5 years of professional experience and have been registered in the Korea Golf Association was recruited. A 250-Hz 8-camera motion capture system (MX-T20, Vicon, LA, USA) was used to capture the motion trajectories of a total of 42 reflective markers attached to the golfer's body and club. Moreover, two 1,000-Hz AMTI force plates (AMTI OR6-7-400, AMTI, MA, USA) were used to measure the ground reaction force. The mean and standard deviation for each parameter were then calculated for both groups of 21 subjects. SPSS Windows version 23.0 was used for statistical analysis. The independent t-test was used to determine the differences between groups. An alpha level of .05 was utilized in all tests. Results: There were differences in joint angles according to gender during golf driver swing. Men showed a statistically significantly higher peak joint angle and maximum range of angle in sagittal and frontal axis of the pelvis, hip, and knee. Moreover, women's swing of the pelvis and hips was found to have a pattern using the peak joint angle and range of angle in the vertical axis of the pelvis and hip. There were the differences in peak joint moment according to gender during golf driver swing. Men used higher joint moment in the downswing phase than women in the extensor, abductor, and external rotator muscles of the right hip; flexor and adductor muscles of left hip joint; and flexor and extensor muscles of the right knee. Conclusion: This result reveals that male golfers conducted driver swing using stronger force of the lower body and ground reaction force based on strength of hip and thigh than female golfers.

• Journal of Biomedical Engineering Research
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• v.24 no.6 s.81
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• pp.523-531
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• 2003

We developed a PC-based 8-channel electrical stimulation system for transcutaneous functional electrical stimulation (FES), and applied it to FES exercise and paraplegic walking. The PC program consists of four parts: a database, a stimulation pattern generator, a stimulus parameter converter, and an exercise program. The stimulation pattern can be arbitrarily generated and edited by using the mouse on the PC screen, and the resulting stimulus parameters arc extracted from the recruitment curves, and transmitted to the 8-channel stimulator through the serial port. The stimulator has nine microprocessors: one master and eight slaves, Each channel is controlled by the slave microprocessor, and is operated independently. Clinical application of the system to a paraplegic patient showed significant increase in the knee extensor torque, the fatigue resistance, and the leg circumference, The patient can now walk about 50 meters for more than 2 minutes.

• The Journal of Korean Physical Therapy
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• v.33 no.4
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• pp.202-209
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• 2021

Purpose: This study examined whether various lower extremity exercises using a Swiss ball in the standing position could improve balance, muscle strength, gait, and fall efficacy in stroke patients. Methods: Twenty-one stroke patients were randomly divided into three groups, each with seven participants. For four weeks, experimental group 1 performed various lower extremity exercises using a Swiss ball, while experimental group 2 executed the same exercises without a Swiss ball, and the control group underwent general physical therapy. The subjects' knee extensor muscle strength, balance, gait, and fall efficacy were evaluated before and after the intervention using portable muscle strength measurement, the Berg Balance Scale (BBS), G-walk, and the Korean Falls Efficacy Scale (K-FES). Results: Knee extensor strength increased significantly in all three groups after the intervention; in particular, a significant increase was seen in experimental groups 1 and 2 compared to the control group. Moreover, all three groups had significantly better BBS scores and higher cadence after the intervention; notably, experimental group 1 had better scores and increased cadence than the control group. Additionally, gait speed was significantly increased in the experimental group 1 than in the control group. The step length of the non-affected leg was also significantly higher in the same group. The K-FES score improved significantly in all three groups, but there was no significant difference between the groups. Conclusion: This study suggests that lower extremity exercises with or without a Swiss ball could be effective interventions to improve muscle strength, balance, gait, and fall efficacy in stroke patients.

• Physical Therapy Korea
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• v.30 no.3
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• pp.194-201
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• 2023

Background: Falls are a common and serious problem in the elderly population. Muscle strength and balance are important factors in the prevention of falls. The Y-balance test (YBT) is used to assess dynamic postural control and shows excellent test-retest reliability. However, no studies have examined the relationship between lower-limb strength and YBT scores in elderly women. Objects: This study aimed to examine the relationship between lower-limb strength and YBT scores in elderly women. Methods: Thirty community-dwelling elderly women participated in the study. Lower-limb strength including hip flexor, hip extensor, hip abductor (HAB), hip adductor (HAD), knee flexor, knee extensor, ankle dorsiflexor, and ankle plantar flexor (PF) muscles was examined using a smart KEMA strength sensor (KOREATECH Inc.), and the YBT was used to assess dynamic balance. Relationship between lower-limb strength and YBT was demonstrated using a Pearson's correlation coefficient. Results: HAB strength (r = 0.388, p < 0.05), HAD strength (r = 0.362, p < 0.05), and ankle PF strength (r = 0.391, p < 0.05) positively correlated with the YBT-anterior direction distance. Ankle PF strength was positively correlated with the YBT-posteromedial direction distance (r = 0.396, p < 0.05) and composite score (r = 0.376, p < 0.05). Conclusion: The results of this study suggest that HAB, HAD, and ankle PF strengths should be considered for dynamic postural control in elderly women.

• Journal of Korean Academy of Nursing
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• v.29 no.2
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• pp.429-444
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• 1999

This study was performed to explore the effects of a dance therapy on physical and psychological characteristics in the elderly. The design of this study was a non-equivalent pre-post test experiment. The subjects consisted of elderly persons living in a facility located in Suweon and Bucheon. Fifty eight subjects, aged between 65 and 93 years who had normal cognition, sensory function, balance, and resting blood pressure. They underwent tests of balance, flexibility, muscle strength, depression, and anxiety as baseline data before dance therapy, and at 6th week and at the end of the 12nd week after following dance therapy. Twenty seven elderly persons were assigned to the experimental group and participated with the dance therapy between April and July, 1998. The dance therapy was developed by the author with the help of a dance therapist and a physiatrist. This therapy was based on the Marian Chace's dance therapy and Korean traditional dance with music. The dance therapy consists of 50 minutes session, 3 times a week for 12 weeks. One session was consisted of warming-up, expression, catharsis, sharing, and closing stage. The intensity of the dance therapy was at the 40 % of age-adjusted maximum heart rates. Data were analysed with mead standard deviation, Chi-square test, unpaired t-test, repeated measures ANOVA, and Bonferroni multiple regression using SAS program. 1. The results related to the physical characteristics were as follows : 1) The balance (standing on one leg, walking on the balancing bar), flexibility and muscle strength (knee extensor, knee flexor, ankle plantarflexor and dorsiflexor) of the experimental subjects significantly increased over time mere than that of the control subjects. 2) The experimental group had significantly higher score for balance, flexibility, muscle strength of knee extensor, and knee flexor than the control group at the 12nd week after dance therapy. 3) The experimental group had significantly higher score for muscle strength of ankle dorsiflexor and plantarflexor than the control group at the 6th week and the 12nd week after dance therapy. 2. The results related to psychological characteristics were as follows : 1) Scores of Geriatric Depression Scale, Hamilton Depression Rating Scale, and Zung's Self-rating Anxiety Scale of the experimental group were significantly decreased over time more than that of the control group. 2) The experimental group had significantly lower score for depression than the control group at the 12nd week after dance therapy. 3) The experimental group had significantly lower score for anxiety than the control group at the 6th week and the 12nd week after dance therapy. The findings showed that the dance therapy could be effective in improving the balances, flexibility, and muscle strength of lower limb, and effective in decreasing the depression and anxiety of the elderly. Additional merits of the dance therapy would be inexpensiveness, easy accessibility, and increasing interpersonal relationship. It can be suggested that the dance therapy is effective in the health promotion of the elderly.

• Journal of the Korean Society for Precision Engineering
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• v.25 no.11
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• pp.107-118
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• 2008

In this study, lower extremity joint kinematics and kinetics and lumbar lordosis were investigated for two different symmetrical lifting techniques(squat and stoop) using the three-dimensional motion analysis. Twenty-six male volunteers lifted boxes weighing 5, 10 and 15kg by both squat and stoop lifting techniques. There were not significant differences in maximum lumbar joint moments between the two techniques. The hip and ankle contributed the most part of the support moments during squat lifting, and the knee flexion moment played an important role in stoop lifting. The hip, ankle and lumbar joints generated power and only the khee joint absorbed power in the squat lifting. The knee and ankle joints absorbed power, the hip and lumbar joints generated power in the stoop lifting. The bi-articular antagonist muscles' co-contraction around the knee joint during the squat lifting and the eccentric co-contraction of the gastrocnemius and semitendinosus were found to be important for straightening up during the stoop lifting. At the time of lordotic curvature appearance in the squat lifting, there were significant correlations in all three lower extremity joint moments with the lumbar joint. Differently, only the hip moment had significant correlation with the lumbar joint in the stoop lifting. In conclusion, the knee extension which is prominent kinematics during the squat tilling was produced by the contributions of the kinetic factors from the hip and ankle joints(extensor moment and power generation) and the lumbar extension which is prominent kinematics during the stoop lifting could be produced by the contributions of the knee joint kinetic factors(flexor moment, power absorption, bi-articular muscle function).

• Physical Therapy Rehabilitation Science
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• v.3 no.2
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• pp.112-118
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• 2014

Objective: The purpose of this study was to investigate the effects of an exercise with and without neuromuscular electrical stimulation (NMES) of the quadriceps femoris muscle, on strength, pain, and weight distribution in patients with knee instability post surgery. Design: Randomized controlled trial. Methods: Twenty patients in the early stage of rehabilitation after knee surgery were recruited as subjects and were randomly divided into either experimental group (exercise combined with NMES) (n=10) or control group (n=10). Both groups received strength training of the lower limb for 20 min/day, 5 days/week for 4 weeks. The experimental group used NMES for unilateral quadriceps femoris training with incremental increases in the intensity of isometric contraction over 4 weeks. Outcome measurements were assessed using the digital manual muscle testing, 30-chair stand test (30CST), numeric pain rating scale (NPRS) and weight distribution using the foot analyzer before and after 4 weeks of training. Results: After the 4-week intervention, knee extensor strength increased significantly in the experimental group post intervention (p<0.05), and there was a significant improvement in the experimental group compared with the control group (p<0.05). The 30CST and NPRS scores improved significantly in the experimental group compared to the control group (p<0.05), and there was a significant difference between the two groups (p<0.05). Weight distribution was significantly improved in the experimental group compared with the control group, (p<0.05), but there was no significant difference in improvement between the two groups. Conclusions: This study showed that NMES combined with strengthening exercises of the lower limbs is effective in improving lower limb pain and strength in patients with instability after knee surgery.

• Journal of Korean Academy of Nursing
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• v.36 no.2
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• pp.341-352
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• 2006

Purpose: This study was conducted to develop & to determine the effect of an tailored falls prevention exercise for older adults. Method: Subjects consisted of 59 older adults (experimental group : 29, control group : 30) living at nursing homes. Experimental group participated in tailored falls prevention exercise for 16 weeks(3 times a week, 50 min every session). Data were collected before the exercise, 16 weeks & 24 weeks after the beginning of exercise. Results: 1) the experimental group significantly improved the muscle strength of hip extensor & flexor, knee extensor & flexor, ankle dorsiflexor, & plantar flexor compared to the control group. 2) the experimental group significantly decreased the mean time for 10 times chair stand. 3) the experimental group significantly increased the standing time on one leg and the number of heel raise for 30 seconds compared to the control group. In addition more older adults in the experimental group completed the tandem stance & semi-tandem stance for 10 seconds than the control group. 4) The experimental group significantly decreased the mean time of 6m walk and the fall frequency compared to the control group. Conclusions: This results suggest that tailored falls prevention exercise for older adults can improve muscle strength, static & dynamic balance and decrease the fall frequency of older adults.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.24 no.1
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• pp.39-46
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• 2018

Background: In most human lives, 80 percent have problems with the ankle and can be solved with a treatment that is objective in proper assessment. Discrepacts in the ankle are also associated with walking patterns and affect hip and knee joints. An evaluation of hip flexion and extensor muscles was performed to check the strength of hip joints after ankle sprain patients application of arthesis. Methods: In the hospital in Bucheon, 20 outpatients who visited the hospital for treatment with ankle sprain were tested with 10 male and 10 female patients. The criteria for selection of the study subjects were randomly divided into those with joint movement techniques applied to the ankle joints and those with conservative physical therapy. Results: In applying arthrography and preservation physical therapy to patients with ankle sprain, a difference in muscle strength between hip flexion and extensor was noted in post-evaluation comparisons. There were significant differences in the assessment of walking speed and walking time between the two counties in the gait analysis assessment (p<.05). Conclusion: Studies have shown that applying arthrography to people with ankle sprain has a greater therapeutic effect than using conservative physical therapy.

• Journal of Digital Convergence
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• v.12 no.9
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• pp.407-415
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• 2014

The purpose of this study is to identify the relation between isokinetic strength of knee extensors and angular velocity of knee joint during fente motion in elite fencers by three disciplines and gender, and to provide the preliminary data for developing the training program and rehabilitation program to enhance sports-performance by three disciplines and gender. Total 31 elite fencers who trained at the national training center of the Korean Olympic Committee (KOC) participated in this study.; 10 fleuret (4 males), 10 epee (6 males) and 11 sabre (5 males). Subjects were measured eccentric and concentric isokinetic strength (PT/BW, WK/BW) of the knee extensors at angular velocity of $60^{\circ}/s$, $180^{\circ}/s$ and $300^{\circ}/s$, and flexion (P1) and extension (P2) angular velocity of knee joint during fente motion. To examine the relationship between isokinetic strength of knee extensor and angular velocity of knee motion, Pearson's correlation coefficient (r). ${\alpha}=.05$ was considered significant. In conclusion, the relationship of isokinetic strength of knee extensors and angular velocity of knee was different depending on three disciplines and gender.