• Physical Therapy Korea
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• v.8 no.2
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• pp.1-16
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• 2001

This study was designed to identify the effects of foot position on electromyographic (EMG) activity of the quadriceps femoris during maximum voluntary contraction (MVC) in standing. Twenty young adults who had not experienced any knee injuries were recruited. Their Q-angles were within a normal range. They were asked to stand in five different foot positions ($40^{\circ}$ externally rotated, $30^{\circ}$ internally rotated, neutral, $20^{\circ}$ plantarflexed, and $10^{\circ}$ dorsiflexed foot position). The EMG activities of the vastus lateralis (VL), rectus femoris (RF), and vastus medialis oblique (VMO) were recorded in standing by surface electrodes and normalized by MVC EMG values derived from manual muscle test. The normalized EMG activity levels (%MVC EMG) of muscles in the five foot positions were compared using repeated measures ANOVA. The EMG activity levels of the VL, RF, and VMO were the highest when foot was externally rotated. The EMG activity levels of the VL and RF were significantly different among the foot positions (p<.05). However, EMG activity levels of the VL, RF, VMO, and VMO/VL ratio did not show significant differences in each foot position (p> .05). The results suggest that the quadriceps femoris may be effectively activated by performing MVC at an externally rotated foot position. Therefore, the externally rotated foot position can be considered as an effective foot position for quadriceps femoris strengthening exercise. Further studies are needed to identify whether there are differences in the effects of foot position on muscle strength after MVC exercise of quadriceps femoris in standing.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.11
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• pp.7285-7292
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• 2015

The purpose of this study was to investigate possibility of a forward gait with backward mechanism(dance gait) as rehabilitation and/or walking exercise by means of biomechanical variables. Thirteen professional women dancers(age, $21.1{\pm}1.3yrs$; height, $159.3{\pm}7.2cm$; body mass, $45.1{\pm}8.4kg$)participated in this study. We found that speed, stride length and double limb support time of a dance gait were more greater than backward gait, but stride width of dance gait less than a backward gait. Maximum RoMs, moments and powers of the lower limb joints on a dance gait were more frequent than a backward dance. These results were judged to be sufficient by the possibility of dance gait as rehabilitation and walking exercise.

• Korean Journal of Clinical Pharmacy
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• v.31 no.3
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• pp.231-236
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• 2021

Background: Sarcopenia is a skeletal muscle disorder that involves the loss of muscle mass and function. Handgrip strength (HGS) is the most commonly used tool to assess muscle strength to diagnose sarcopenia. HGS is also associated with various diseases and health outcomes. Thus, we aimed this study to examine the HGS status in Korean adults and relevant factors of HGS. Methods: Data was obtained from the 7th Korea National Health and Nutrition Examination Survey (KNHANES), a population-based nationwide survey. The estimated mean value of HGS was calculated in each age group. The mean HGS in men and women aged over 40 was compared according to the household income level, lifestyle factors, and comorbidities. Results: A total of 16,708 participants were included in this study. The mean HGS showed a maximum value in the 30s for both men and women, and then tended to decrease with increasing age. When analyzed for people aged 40 or older, the mean HGS was significantly higher in the current or past smoker, drinker, and aerobic exercise groups in both men and women. The mean HGS was lower in the group with comorbidities such as hypertension, dyslipidemia, type 2 diabetes, and bone diseases. Conclusion: Our study found that the mean HGS was significantly different between those with and without underlying chronic diseases. In groups with relevant comorbidities, close monitoring for the development of sarcopenia and taking preventive measures such as exercise and nutritional support may be recommended.

• Physical Therapy Korea
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• v.26 no.4
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• pp.63-69
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• 2019

Background: Both the rapid concentric and eccentric contractions during exercise repeatedly impose excessive stress on muscle tissue. The hamstring muscles are very susceptible to injury due to the tensile stress. Various interventions are currently being undertaken to prevent strain injury before exercise. Stretching is the most common method and is known to have a positive effect on flexibility and muscle performance. However, relatively few studies have investigated the potential negative factors of stretching. Objects: The purpose of this study was to examine changes in pain following the different intensity of the stretching and types of physical stress. Methods: The subjects were divided into three groups based on the intensity of stretching: 100% (S100), 75% (S75), and 50% (S50) of the measured force at the point of discomfort in static stretching and 100% (P100), 75% (P75), and 50% (P50) of the maximum voluntary isometric contraction in Proprioceptive Neuromuscular Facilitation (PNF) stretching. The pain individual subjects perceived after stretching was measured via a Visual Analog Scale (VAS) and compared between the groups Results: Despite the decrease in the intensity of static stretching, no decrease in VAS value was observed. In PNF stretching, a significant decrease was observed at P50 compared to P100. S100 was significantly higher than P75 and P50. Conclusion: Previous studies have shown that PNF has a superior or the same effect on flexibility in comparison with static stretching. This effect was maintained even in moderate intensity. PNF stretching performed under moderate rather than high intensive static stretching, which causes pain and discomfort, might be recommended in clinical settings.

• Nutrition Research and Practice
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• v.17 no.4
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• pp.762-779
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• 2023

BACKGROUND/OBJECTIVES: Mediterranean diet is an environmentally friendly and healthy diet model. The diet offers many vegetables, fruits, nuts, and olive oil to consumers. In addition, it provides moderate amounts of fish and chicken, smaller quantities of dairy products, red meat, and processed meat. The Mediterranean diet has a high anti-inflammatory and antioxidant content, and it causes many physiological changes that can provide a physical performance advantage. This study examined the effects of a 15-day menu, which was planned using foods with a low acid load within the Mediterranean diet rules, on the exercise performance, lactate elimination, anthropometric measurements, and body composition. SUBJECTS/METHODS: Fifteen professional male athletes between the ages of 13 and 18, who were engaged in ski running, were included in the experimental study. Dietary intervention was applied for 15 days. The athlete performances were evaluated by applying the vertical jump test, hand grip strength, 20 meters shuttle run test, and Borg fatigue scale. After the shuttle run test (every 3 min for 30 min), blood was drawn from the finger, and the lactate elimination time was calculated. Performance and lactate measurements, body analysis, and anthropometric measurements were taken before and after dietary intervention. RESULTS: The vertical jump height and hand grip strength increased after the intervention (P < 0.05). The test duration, total distance, the number of shuttles, and maximum oxygen consumption parameters of the shuttle run test increased (P < 0.05). After the intervention, the athletes' perceived fatigue scores decreased in several stages of the shuttle run test (P < 0.05). The lactate elimination time and athlete's body composition were similar in repeated measurements (P > 0.05). In the last measurements, the upper middle arm circumference decreased while the height of the athletes increased (P < 0.05). CONCLUSIONS: These results show that the Mediterranean diet is a safe and feasible dietary approach for aerobic performance and strength increase.

• Journal of Ginseng Research
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• v.31 no.2
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• pp.93-101
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• 2007

The purpose of this study is to examine the improvement of endurance exercise performance by taking mixtures of Ginseng Radix rubra and Paeonia Radix. For this purpose, time of exhaustion, $V0_2max$, heart rate, and blood lactate was used as improvement index. The experiments were executed to thirty eight men in their twenties. They were randomly assigned into four groups[CG: control group(n=10), IG: ingestion mixtures group(n=9), TPG: ingestion placebo+training group(n=9), TIG: ingestion mixtures+training group(n=10)]. IG and TIG took mixtures of Ginseng Radix rubra and Paeonia Radix for four weeks, and TPG and TIG exercised once a day, three times a week, exercised for 25 minutes during the first week and added 2 minutes by week during four weeks up to 75% of their maximum heart rate. Time of exhaustion showed statistically significant increase for IG, TPG and TIG. TIG had the longest time of exhaustion and IG the shortest. In case of $VO_2max$, no statistically significant change was found among four groups. However, IG, TPG, TIG showed small increase in $VO_2max$. Similarly, no significant change was found for heart rate in rest even though TIG and TPG appear to have decreasing trend. For maximum heart rate, no significant change was found either, but IG, TPG and TIG showed increase. In case of blood lactate from rest to exercise until 18 minutes, no group had significant decrease. In case of blood lactate in exhaustion, IG, TPG and TIG had significant increase. Blood lactate recovery volume at 5 minutes, 10 minutes, 20 minutes showed no significant results for all four groups, but TIG and TPG had a small increase.

• Korean Journal of Adult Nursing
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• v.12 no.3
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• pp.431-451
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• 2000

In this paper, I will examine the variables influencing the Quality of Life of arthritis patients and present basic materials which help arthritis patients have positive thinking in life and ultimately lead a satisfactory life. The subjects for this study are 231 inpatients and outpatients with arthritis living in J and K city in Chonbug Province. For the analysis of collected data I employed the SAS program. The variables for characteristics and the quality of life were analysed by descriptive statistics, T-test and ANOVA, and the relations among variables were analysed through Pearson Correlation; the Regression method was employed to predict the factors affecting quality of life. For the validity of reliance on measuring equipment Cronbach Alpha was used. The results of the study are as follows : (1) The mean score of quality of life of arthritis patients is 3.09(5 in the maximum). The general characteristics which affect the quality of life are age(F=5.13, p=0.0006), standard of education(F=6.49, p=0.0003), marriage status(F=7.77, p=0.0005), monthly pay(F=4.37, p=0.0020), medical benefits (F=4.85, p=0.0087), and supports(F=4.39, p=0.0050). For the disease-related characteristics, there is a significant difference in the 6 items: pain control method(F=5.92, p= 0.0002), physical therapy(F=3.25, p=0.013), whethere or not patients exercise(F=4.62, p=0.0000), regularity of exercise(F=4.79, p=0.0000), frequency of exercise(F=6.29, p=0.0001), and amount of exercise(F=4.62, p=0.0043). Depending on the type of arthritis, there is also a significant difference in the degree of pain felt. The patients with infectious arthritis suffer from pain the most, followed by those with gout, rheumatism and degenerative arthritis, in that order. Although statistics don't show any convincing evidence, those with gout perceive that they are in best health condition, followed by those with rheumatism, degenerative arthritis, and infectious arthritis, in that order(F=2.23, p=0.0669). (2) The quality of life of arthritis patients is correlated positively with perceived health status(r=0.56, p=0.0001), health promoting behavior(r=0.53, p=0.0001), family support (r=0.46, p=0.0001), amount of exercise (r=0.36, p=0.0001), ADL(r=0.36, p=0.0001), HLOC(r=0.32, p=0.0001), frequency of exercise(r=0.32, p=0.0001)in that order, while correlated negatively with the degree of pain felt(r=-0.32, p=0.0001), the number of pain regions(r=-0.19, p= 0.0041), and the duration of pain(r=-0.14, p=0.0279). (3) Regression analysis reveals that the most powerful predictor of the quality of life is perceived health status, which account for 31.11%. The other predictors of the quality of life, which account for 60.22%, are health promoting behavior(16.51%), family support(3.81%), ADL(2.52%), gender(1.86%), the number of family members(1.36%), level of pain(1.24%), duration of pain (1.08%), and level of education(0.67%). The results of the study show that perceived health status and health promoting behavior are the two most important variables. However, considering that the perceived health condition is difficult to control by nursing intervention, it is suggested that the level of expectation for patients, must be decided first, and the health promoting behavior and the family support influencing the quality of life must be taken into account as targets for nursing intervention. As a way of controlling the quality of life, I think that a more comprehensive approach comprising the above important variables along with demographic and general characteristics is needed. I also suggest that we must continue to explore the variables affecting the quality of life and include those variables in nursing intervention.

• Journal of the Korean Applied Science and Technology
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• v.37 no.1
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• pp.17-27
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• 2020

The purpose of this study is to confirm the effects of a 6-week high-intensity combined training program on canoe athletes' cardiorespiratory function, isokinetic trunk strength, and anaerobic power. For the purpose of this study, the high-intensity combined training program was applied to 9 high-school canoe athletes. The high-intensity combined training program consists of aerobic exercise performed 2 times a week (Tuesday and Thursday), anaerobic exercise performed 3 times a week (Monday, Wednesday, and Friday), and flexibility exercise performed 5 times a week. The core of the high-intensity combined training program was the anaerobic training program performed with 100% weight for repetition; otherwise, the existing training method was divided into the percentage (%) of the 1RM. The aerobic exercise and the gym ball exercise are performed subsidiarily. Results showed that there was a statistically significant difference in height and muscle mass, whereas there was no statistically significant difference in weight, body fat percentage, and BMI followed by the high-intensity combined training program. There were statistically significant differences in maximum oxygen uptake and total exercise time. The angular velocity of 30°/sec showed a statistically significant difference in the peak torque item of flexors only. Also, the angular velocity of 120°/sec showed a statistically significant difference in the total work item of extensors only; however, there was no statistically significant difference in all the items of peak power, average power, and peak drop. In conclusion, it seems that the high-intensity combined training program may be applied as a training program for enhancing canoe athletes' performance. For further studies, more than 6 weeks training program with more participants would show improved results of isokinetic strength and anaerobic power in athlets.

• Korean Journal of Human Ecology
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• v.11 no.3
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• pp.273-285
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• 2002

Three materials for sport underwear were manufactured by order for study, and among them, suitable material in order to perform an experiment on the effect of wearing was adopted. The results are as follows: The result of wearing an experimental clothes for sports manufactured as a foundation-type underwear for sports showed that if the same compositional materials were applied, laminating material had higher rate than that of others in the amount of sweat. Concerning relative humidity in clothes and the amount of sweat absorbed in clothes among the two kinds of materials which were produced by laminate, material 2(nylon+modal) was statistically exerts higher influence on the amount of sweat. The humidity in clothes keeps the optimal condition of 59.8%, and breast part showed the highest relative humidity. The material 2(nylon+modal) showed the highest comfortableness, the sense of warmth, humidity and voluminousness, and the sense of pressure. Follow-up survey revealed that in case of material 2, higher amount of sweat than that of the group objects in its early phase, and the amount of sweat varies from individuals. The temperature in clothes of folded parts of experimental clothes and maximum surface temperature was equivalent to that of average skin. With the lapse of time, the weight decreased of 11.03% in maximum, and 3.12% in minimum. The amount of change in the girth was greater in part of body frame than that of limbs, and especially, navel and waist part showed high decrease, and upper breast, breast and the largest part of abdomen showed relatively low decrease. The above experiment revealed that materials for suitable to the underwear for sports for loss of weight by an exercise should be made of doubled-nylon and modal, along with the laminate processing, which heightens the amount of sweat. Thus, wearing an experimental wear gave satisfaction in the view of the beauty of appearance as it did not discharge flowing secretion to the outside at the time of exercise.

• 한국체육학회지인문사회과학편
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• v.51 no.5
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• pp.639-647
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• 2012

The purpose of this study was to examine the effects of varied resistance training intensities and rest intervals between training sets on integral electromyography (iEMG), repetition rate, and total work. All subjects, 14 college students, were tested one repetition maximum (1RM). Then, all subjects were weekly tested with 9 practice procedures, composed of diverse intensities (60, 75, 90% of 1RM) and rest intervals (1, 3, 5 min). As results show, to maintain the same load and target repetition maximum for an untrained person, muscular power training (90% of 1RM), muscular hypertrophy training (75% of 1RM), and muscular endurance training (60% of 1RM) should be applied with 5 min or longer rest interval periods for 3 training sets. In addition, 2 training sets with 3 min rest intervals and a set with an 1 min rest interval were capable by the subjects. Thus, at least 3 min or longer rest intervals should be applied to maintain multiple training sets. In case for muscular endurance training, which requires shorter rest intervals, the intensity of exercise should be adjusted to 60% of 1RM or less. In conclusion, depending on diverse purposes of resistance training such as improving muscular power, muscular hypertrophy, or muscular endurance, appropriate exercise intensity and rest intervals should be applied.