• Journal of the Korean Applied Science and Technology
• /
• v.41 no.3
• /
• pp.813-824
• /
• 2024

This study was conducted to evaluate the long-term effects of training on the physical development and exercise performance of adolescent weightlifters, aiming to provide effective training and management strategies for improving competitive performance. In order to achieve the objectives of the study, adolescent weightlifters from middle and high schools in Chungcheongnam-do province [male middle school-aged athletes, n=5; female middle school-aged athletes, n=5; male high school-aged athletes, n=12; female high school-aged athletes, n=8] were examined over approximately 10 months of weightlifting-based training to analyse the changes in body composition, physical fitness (muscular strength, muscular endurance, agility, flexibility, dynamic balance, coordination), and isokinetic muscular function (trunk and lower extremity). As a result, it was found that the physical development of middle and high school-aged athletes underwent physical development primarily characterized by an increase in lean body mass. Additionally, back muscle strength and power, which contribute to rapid and efficient force transmission between the upper and lower body, as well as grip strength necessary for controlling the barbell with a stable grip, are significant factors. These aspects were notably enhanced through specialized training and competitive experience for weightlifting performance at the high school level. On the other hand, changes in factors beyond the primary physical attributes contributing to weightlifting performance were limited, suggesting differences in effectiveness likely stemming from the specific composition of training programs or the athletes' experience and skill levels. Collectively, the findings from this study, which evaluates the physical characteristics and exercise abilities of adolescent weightlifters, are expected to contribute to improved competitive performance of weightlifters.

• PNF and Movement
• /
• v.8 no.3
• /
• pp.9-16
• /
• 2010

Purpose : The purpose of this study was to investigate effects of kinesio taping of thigh muscle on isokinetic muscular function during closed kinetic chain exercise of lower extremity. Methods : Twenty healthy males were participated in this study. The isokinetic muscular function of closed kinetic chain were measured for peak torque, peak torque % body weight, average power, max rep tot work before and after application of kinesio taping on thigh muscles. Results : At $60^{\circ}/s$ peak force and peak force % body weight were significant increased in both extension(p<0.01) and flexion(p<0.001) after applying kinesio taping. At $180^{\circ}/s$ average power was significant increased in both extension and flexion after applying taping(p<0.001). At $240^{\circ}/s$ max rep tot work was significant increased in both extension(p<0.001) and flexion(p<0.05). Conclusion : This study suggests that application of kinesio taping on thigh muscle was more effective to improve isokinetic muscular function in closed kinetic chain exercise of lower extremity.

• Korean Journal of Applied Biomechanics
• /
• v.20 no.1
• /
• pp.75-81
• /
• 2010

Knee osteoarthritis is one of the most prevalent arthritis that weakens the muscles. This study focused on evaluating muscular functionality of knee osteoarthritis subjects. Muscular strengths of muscles around knee and hip joints of middle-aged female subjects aged over 40 suffering from knee osteoarthritis were evaluated by isokinetic dynanometer. Also, relation between the observed muscle imbalance in knee and hip joints and visual analogue scale was investigated. Subjects performed 8-weeks exercise on weakened muscles - particularly on knee extensors and hip abductors - and had their isokinetic muscular functionalities analyzed again. After the 8-weeks exercise, subjects' thigh circumferences were increased, accompanied with muscular strength improvements and decrease in visual analogue scale. Hence we emphasize the importance of exercise for muscular strength enhancement of knee extensors and hip abductors, in rehabilitation programs for knee osteoarthritis.

• Journal of Korean Orthopaedic Sports Medicine
• /
• v.10 no.2
• /
• pp.61-68
• /
• 2011

Purpose: We evaluated the clinical outcome after arthroscopic repair in full thickness rotator cuff tears with and without delamination. Materials and Methods: From March 2006 to October 2008, we included 48 consecutive shoulders (31 males, 17 females; mean age 57.6 years; 45~68) who had arthroscopic double row repair for fullthickness tears of the rotator cuff. Mean rotator cuff tear size was 2.8 cm (range: 1.2~3.6) and the techniques of tendon-to-bone fixation varied according to the presence of delamination; separate row fixations of bursal and articular layer were used in delaminated tear. The mean follow-up was 26 months (range: 18~33) and functional and structural results were evaluated by American Shoulder and Elbow Surgeons (ASES), University of California at Los Angeles (UCLA) scale, isokinetic strength testing and magnetic resonance imaging (MRI) obtained mean 8 months (range:6~13) postoperatively. The patterns of delamination, age, sex, symptom duration, size of tear, satisfaction rate, retear rate ware compared and significance was set at p values < 0.05. Results: Postoperative functional shoulder score improved significantly in 44 shoulders (91.7%). Delamination was observed in 15 shoulders (31%) and it extended proximally and posteriorly in the majority of shoulders, and the articular layer was thicker (8/15, 53%) and more retracted (9/15, 60%) compared with the superficial bursal layer. Final follow up functional shoulder scores showed no differences between non-delaminated and delaminated tears and the presence of delamination had no correlations with sex, symptom duration, tear size and satisfaction rate, however, older age had more delaminated tears (p=0.041). Follow up MRI in 29 shoulders revealed that fourteen (48%) shoulders had complete healing; nine (31%), partial healing; six (21%), complete retear but the half of the retear group showed favorable clinical results. 79% (15/19) in non-delaminated tear and 80% (8/10) in delaminated tear were judged as healed tendon on MRI and double-layer double row repairs in delaminated tears resulted in nearly same rate of structural integrity of single-layer double row repairs (p=0.165). Conclusion: The incidence of delamination in our series was 31% and older age had more delaminated tears. Sex, symptom duration, preoperative size of the tear, functional results and satisfaction rate had no significant correlations with the presence of delamination. Nearly the same postoperative structural integrity was noted in both delaminated and non-delaminated tears.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.18 no.10
• /
• pp.480-489
• /
• 2017

Blood flow restriction(BFR) exercise is defined as low intensity and short term exercise using pneumatic pressure belts at the top of limbs, which affects the physiological functions of the body. The purpose of this study was to investigate the effects of walking exercise with BFR on inflammatory index, isokinetic muscle function, and thigh circumference in obese women. Eleven obese women(> BMI $25kg/m^2$ & > body fat 30%) wore pneumatic pressure belts on both femurs and performed walking exercise twice per day, 3 days/wk for 4 weeks (walking 2 min; resting 1 min). Data analysis was carried out using paired t-test. Body weight, BMI, and body fat significantly decreased after exercise(p<.05), and right thigh circumference significantly decreased(p<.05). The concentration of plasma IL-6 significantly increased(p<.05) after exercise. TNF-${\alpha}$ level was not statistically different but tended to slightly increase. CRP slightly decreased, although it did not reach statistical significance after exercise. Muscle strength significantly increased in the $60^{\circ}/sec$ of right/left side extension, left side flexion, and $180^{\circ}/sec$ of left side extension after training(p<.05). These results suggest that 4 weeks of blood flow restriction walking exercise has positive effects on inflammatory index and isokinetic muscle function. Therefore, we consider that blood flow restriction exercise can be used for treatment of obesity, related chronic diseases, and metabolic syndrome. Further, blood flow restriction exercise for a short time has similar effects as a high intensity resistance program.

• Journal of rehabilitation welfare engineering & assistive technology
• /
• v.12 no.1
• /
• pp.53-62
• /
• 2018

In this study, we developed a smart 1RM system for national health management and physical fitness, which enables quantitative 1RM measurement in various types of exercise using digital pulley technology, and to test the effect on training by using it. We developed the smart 1RM system, which is composed of portable muscle strength measuring device, Bluetooth communication based mobile phone data transmission and circuit diagram, and height adjustable system body. We recruited the 30 participants with 20th aged and divided into training and non-performing groups with 15 participants randomly. The participants performed 5 sets of elbow, lumbar, knee extension / flexion 10 times using smart 1RM system and the experimental period was 3 days a week for a total of 8 weeks. The experimental results showed that the maximum strength of the elbow, lumbar, and knee joints was significantly improved before and after maximal muscle strength training in the training group. Oxygen intakes during 1RM exercise mode showed 10.91% than endurance. To verify the validity of the smart 1RM maximal strength data, the reliability was 0.895 (* p <0.00). This study can be applied to the early rehabilitation treatment of the elderly and rehabilitation patients more quantitatively using the national health care.

• Journal of Korean Clinical Health Science
• /
• v.3 no.2
• /
• pp.311-319
• /
• 2015

Purpose. This study of purpose was to compare and analyze the relationship among the isokinetic trunk muscular functions, flexibility and low back pain of elite weight lifter with regard of sex. Methods. we measured the level of low back pain, isokinetic muscular functions according to gender, then analyzed the relationship between isokinetic functions and the level of low back pain, between flexibility and the level of pain, between Athletic Career and the level. Results. In this study, the gender, the VAS point was $2.6{\pm}2.3$ and the VRS point was $2.3{\pm}1.3$ in males. The other side, in females the VAS points was $3.6{\pm}1.7$ and the VRS was $3.2{\pm}1.1$. There was significant negative correlation(r=-0.826) between the VAS point and the maximal flexion muscular strength per kilogram of $30^{\circ}/sec$ isokinetic exercise in female. also there was negative correlation between the muscular flexion strength per kilogram and the VRS point in female, but there was no significant relationship in male. Conclusions. In current study, these results suggested that the higher muscular flexion strength per kilogram is, the lower the level of low back pain is in female athletes. this is caused by the imbalance between Abdominal Muscles and Back Extensor in weight lifter. Therefore, there is the need to apply the program to improve the balance of trunk.

• Journal of the Korean Society of Physical Medicine
• /
• v.13 no.3
• /
• pp.27-37
• /
• 2018

PURPOSE: The purpose of this study was to investigate and evaluate muscle activity and foot pressure during gait, and isokinetic strength and balance in persons with functional ankle instability (FAI). METHODS: Nine healthy subjects (CON, n=9) without FAI and 11 patients (FAI, n=11) with FAI participated in the study after having been screened with an ankle instability instrument and a balance error scoring system. In addition, FAI was classified as non-involved (FAI-N) or involved (FAI-I), and CON was classified as dominant or non-dominant. All subjects were evaluated for isokinetic strength (plantar flexion, dorsiflexion, inversion and eversion of $30^{\circ}/sec$ and $60^{\circ}/sec$), balance (static and dynamic), muscle activity (tibialis anterior, peroneus longus and gastrocnemius) and foot pressure (static and dynamic) during gait. RESULTS: Results showed that plantar flexion (p<.05), dorsiflexion (p<.05), inversion (p<.01) and eversion (p<.00) of $60^{\circ}/sec$ were significantly decreased in FAI-I compared to those in FAI-N and CON. C 90 of static balance with eyes open (p<.01) and closed (p<.00) were significantly increased in FAI compared to those in CON. Forward position of dynamic balance (p<.01) was significantly decreased in FAI compared to that in CON. Gastrocnemius and peroneus longus of dynamic muscle activity (p<.01), left and right weight distribution of static foot pressure (p<.00) and pressure distribution of dynamic foot pressure (p<.00) were significantly decreased in FAI-I compared to those in FAI-N. CONCLUSION: We demonstrated that ankle strength, balance, muscle activity and foot pressure were significantly correlated with FAI.

• The Korean Journal of Emergency Medical Services
• /
• v.9 no.2
• /
• pp.129-136
• /
• 2005

The purpose of this study was to compare the level of physical fitness and isokinetic strength, between EMT student and physical education students. Nine a major in EMT student volunteers, and nine a major in physical education student volunteers participated in that study as subjects. The basic physical body composition, fitness and isokinetic strength were measured. The data obtained in the study was analyzed by SPSS PC+ for window version 10.0. The difference in the mean of each variable between the two groups was analyzed by using the independent t-test and the significance level for all analysis was set at <.05. The results were as follows ; 1. There was a significant difference in the basic physical fitness between the two groups with the exception flexibility. The difference showed the statistical significance on back strength, balance and power in physical education students. 2. There were significant difference in body composition between the two groups with the exception of lean body fat. The difference showed the statistical significance on body fat%, body fat mass in the physical education students. 3. There was significant defference in the isokinetic strength between the two group. The difference showed the statistical significance on peak torque, peak torque B/W%. It was concluded that the physical education students may not have an effect of flexibility; however, back strength, balance, power, body composition, isokinetic strength, could be enhanced due to the long-term period of training. Based on the findings of this study, the regular participation of regular exercise help the untrained men achieve health-related fitness.

• Korean Journal of Applied Biomechanics
• /
• v.32 no.3
• /
• pp.103-110
• /
• 2022

Objective: The aim of this study was to investigate effect of core stabilization exercises on the erector spinae contractile properties and trunk isokinetic muscle function of middle age with low physical activity and sedentary lifestyle. Method: Twenty (female: n=10, male: n=10) middle-age subjects (age: 37.25 ± 6.08 years, height: 168.01 ± 6.84 cm, weight: 71.37 ± 11.75 kg) participated in this study. Tensiomyography was measured on the erector spinae, and the isokinetic trunk muscle function test was measured at an angular velocity of 60 °/s and 90 °/s. All subjects performed the core stabilization exercises for 60 min per day, 3 times a week, for 7 weeks. A paired t-test was performed with a significance level of 0.05. Results: Tensiomyography of the erector spinae revealed a significant post-exercise increase in the maximum radial displacement (p < .05) and velocity of contraction (p < .05), however, there wasn't a significant post-exercise change in the contraction time. Additionally, the isokinetic muscle function test of the trunk revealed a significant post-exercise increase in trunk extensor relative strength (p < .05) and strength ratio (p < .05). Conclusion: Our results indicated that core stabilization exercises reduced erector spinae muscle stiffness, increased the velocity of erector spinae contraction. Additionally, data showed the improvement in the trunk extensor strength help induce a more balanced development in trunk muscle.