• Journal of The Korean Society of Integrative Medicine
• /
• v.8 no.2
• /
• pp.97-107
• /
• 2020

Purpose : The purpose of this study is to investigate the effect of squat exercise using a ball on the gap between knees and Q angle of a subject with a genu-varum, and to prove the effect, to provide a clinical basis for developing into a knee correction exercise program. Methods : As a result of posture measurement through GPS, 26 female with genu-varum with a knee length of 5 cm or more were studied. The group was randomly assigned to 13 squat exercise group using ball (experimental group) and 13 general squat exercise groups (control group). The experimental group placed the ball between both knees in a position where the distance between both feet was slightly wider than the shoulder width on a flat support surface, and fixed the ball, and then squat with the start signal. The control group squats without a ball. Each group performed three sets of exercise three times a week for six weeks. Before their exercise, after three and six weeks, EMG, GPS, digital goniometer measurement, the vastus medialis (VM), the vastus lateralis (VL), and the Q-angle were measured in the squat exercise posture. EMG was measured in squat exercise posture. Results : The distance between the knees was reduced. EMG is activated in group A, the group B experimental results showed the high activity of the VL. Q-angle had increased. But the experimental group increased more than the control group. Conclusion : We have confirmed through our experiments that the distance interval between the knees during squat exercises using a ball can be reduced. Furthermore, it would also be helpful to ensure the treatment of genu-varum.

• PNF and Movement
• /
• v.17 no.3
• /
• pp.441-450
• /
• 2019

Purpose: This study identified the co-activation of quadriceps and hamstring muscles during hamstring strengthening exercises in healthy adults. Methods: Twenty-one participants were required for the present study design to achieve 80% power, 0.8 effect size (η2), and an alpha level of 0.05. Thus, this study recruited 21 healthy adults. All participants performed Nordic exercises, bridge exercises, and one-leg deadlifts randomly. The activity of the rectus femoris, vastus medialis (VM), vastus lateralis (VL), biceps femoris (BF), and semitendinosus (SM) were measured. In addition, the ratios of VM/VL and hamstring/quadriceps (HQ) were measured during the three hamstring strengthening exercises using electromyography. One-way ANOVA was used to compare the co-activation of quadriceps and hamstring muscles in the three exercises. Results: The activity of VM and VL during the performance of one-leg deadlifts was significantly higher than the other two exercises. The BF had significantly higher activity during the Nordic exercises compared to the other two exercises. In addition, the SM activation was significantly greater during Nordic exercises than one-leg deadlifts. Additionally, there was significant difference in HQ ratio among hamstring strengthening exercises. In specific, the one-leg deadlifts yielded a significantly lower HQ ratio. Conclusion: This study revealed that one-leg deadlifts are effective in rehabilitation for anterior cruciate ligament injury. In addition, Nordic exercises can be recommended to facilitate hamstring muscle activation.

• Korean Journal of Applied Biomechanics
• /
• v.25 no.1
• /
• pp.103-111
• /
• 2015

Objective : The purpose of this study was to evaluate the effect for running shoes with resilience of midsole on biomechanical properties. Methods : 10 healthy males who had no history of injury in the lower extremity with an average age of 26.5 year(SD=1.84), height of 172.22 cm(SD=4.44) and weight of 67.51 kg(SD=6.17) participated in this study. All subjects ran on the treadmill wearing three different running shoes. Foot pressure data was collected using Pedar-X system(Novel Gmbh, Germany) operating at 100 Hz. Surface EMG signals for biceps femoris, rectus femoris, vastus lateralis, medial lateralis, tibialis anterior, medial gastrocnemius, soleus and peroneus longus were acquired at 1000 Hz using Bignoli 8 System(Delsys Inc., USA). To normalize the difference of the magnitude of muscle contractions, it was expressed as a percentage relative to the maximum voluntary contraction (MVC). The impact resilience of the midsole data was collected using Fastcam SA5 system(Photron Inc., USA). Collected data was analyzed using One-way ANOVA in order to investigate the effects of each running shoes. Results : TPU midsole was significantly wider in contact area than EVA, TPE midsole in midfoot and higher in EMG activity than EVA midsole at biceps femoris. TPE midsole was significantly wider in contact area than EVA midsole in rearfoot and higher in peak pressure than EVA midsole in forefoot. EVA midsole was significantly higher in EMG activity than TPU midsole at tibia anterior. In medial resilience of midsoles, TPE midsole was significantly higher than EVA, TPU midsole. Conclusion : TPU midsole can reduce the load on the midfoot effectively and activate tibialis anterior, biceps femoris to give help to running.

• Korean Journal of Applied Biomechanics
• /
• v.21 no.3
• /
• pp.345-352
• /
• 2011

The purpose of this study was to determine how spandex wear with compressive band affects biomechanical parameters during a golf swing. Nine male golf players, each with at least 6 years golf experienc(handy 4.5${\pm}$5.4), were recruited as the participants. Eight pairs of surface electrodes were attached to the left and right side of the body to monitor the pectoralis major(PM), external abdominal oblique(AO), erector spinae(ES), and vastus lateralis(VL). This study showed that the angular velocity of the club in EG were increased during the down swing phase but X-Factor and X-factor Stretch were reduced. Average and maximum nEMG (normalized EMG) values of the left AO(external abdominal oblique) were less in EG(experimental group) compared with CG(control group) during the back swing, whereas those of left PM(pectoralis major) in EG were greater than CG. It is more likely that EG performed effectively golf swing without excess muscle activity. Thus, the spandex wear with compressive band played an important role in improving swing performance with injury prevention. This has led to suggestions of the need for further kinetic and kinematic analyses to evaluate its function.

• The Journal of Korean Physical Therapy
• /
• v.11 no.1
• /
• pp.129-136
• /
• 1999

The purpode of this study was to determine the EMG characteristies of 7 subjects with hemiplegic gait receiving therapeautic exercise after stroke. The akin electrode and gait analysis system were used. The normal gait of 6 health volunteers was analysised. The results were following. 1. Gluteus maximus, the extensor of hip joint had high level of activity compared to normal, and had two peak in late stance phase and early Swing phase. 2. Medial hamstring, the flexor of knee joint had low level of activity compared to normal, and had continuous low amplitude pattern. 3. Vastus lateralis, the extensor of knee joint had high level of activity compared to normal, and had not continuous high amplitude. From early stance phase and mid stance phase, activity had high level but after swing phase. similar to normal. 4. Gastrocnemius, plantar flexor of ankle joint had low level of activity compared to normal and had continuous low amplitude. 5. Tibialis anterior, dorsiflexor of ankle joint had similar muscle activity to normal and had continuous low amplitude.

• Korean Journal of Applied Biomechanics
• /
• v.22 no.3
• /
• pp.357-363
• /
• 2012

The purpose of this study was to investigate the effects of different saddle heights on lower-limb joint angle and muscle activity. Six elite cyclists(age: $32.2{\pm}5.2years$, height: $171.0{\pm}3.5cm$, weight: $79.7{\pm}5.6kg$, cycle career: $13{\pm}6.2years$) participated in three min. submaximal(90 rpm) pedaling tests with the same load and cadence based on saddle heights where subject's saddle height was determined by his knee flexion angle when the pedal crank was at the 6 o'clock position. Joint angles(hip, knee, ankle joints) and the activity of lower limb muscles(biceps femoris(BF), vastus lateralis(VL), tibialis anterior(TA) and gastrocnemius medial(GM)) were compared by measuring 3D motion and electromyography(EMG) data. Results showed that there were significant differences in minimum hip & knee joint angle and range of motion of hip and knee joint between saddle heights. Onset timing and integrated EMG of only BF among 4 muscles were significantly different between saddle heights. Especially there was a negative relationship between minimum hip joint angle and onset timing of BF in most subject, which means that onset timing of BF became fast as the degree of bending of the hip joint became larger by saddle height. Optimal pedaling will be possible through increased amount of muscle activation due to the appropriate burst onset timing by proper pedaling posture with adjusted saddle height.

• Journal of the Ergonomics Society of Korea
• /
• v.26 no.2
• /
• pp.157-165
• /
• 2007

The Work-Related Musculoskeletal Disorders (WMSDs) can be occurred by various factors such as repetition, forceful exertions and awkward postures. Especially, occurrences of the WMSDs on the waist and lower limb are reported in workplaces, demanded standing postures for a long time, in service and manufacturing industry. The static and standing postures without movement for a long time increase work loads to the lower limb and the waist. Accordingly, anti-fatigue mat or anti-fatigue insole is used as a preventing device of the WMSDs. However anti-fatigue mats are limited in space and movement. In this study, multi-elastic insoles are designed and shown the effects of the workload reduction for a long time under the standing work. The foot pressures and EMG (Electromyography) are measured at 0 hour and after 2 hours by 6 health students in their twenties. The 6 prototype insoles are designed with three elastic (Low, Medium and High). These insoles are compared with no insole (insole type 7) as control group. The EMG measurement was conducted to waist (erector spinae muscle), thigh (vastus lateralis muscle) and calf (gastrocnemius muscle). The foot pressure is analyzed by mean pressure value and the EMG analysis is investigated through MF (Median Frequency), MPF (Mean Power Frequency) and ZCR (Zero Crossing Rate). The results of the foot pressure show that the multi-elastic insoles had smaller foot pressure value than that of no-insole. Moreover, Insole 2 and Insole 3 have the smallest increasing rate in foot pressure. The EMG results show that the multi-elastic insoles had smaller EMG shift value than that of no-insole in 2 hour, and then shift value shows the smallest value in Insole 2. Therefore, this study presents that the multi-elastic insoles have reducing effects of the work load for a long time standing work in both side of foot pressure and EMG.

• Journal of the Ergonomics Society of Korea
• /
• v.27 no.3
• /
• pp.71-79
• /
• 2008

Walking shoes for walking and jogging have been used to enjoy lots of leisure time. Functional shoes such as walking shoes have special functions to improve body motility by changing of shoe shapes. The walking shoes could improve the motility by structural transformation of outsole as increase degrees of heel and toe. The study on insoles has not been conducted enough on the contrary of the study of outsole. The purpose of this study is to perform ergonomics analysis whether the Arch Supported insoles have an improving effect of muscle activities or not. Experiments were performed with 6 subjects who are health and haven't experienced any diseases past. EMG(Electromyography) and Foot Pressures were measured repeatedly for 5 seconds at 0 hour, after 1 hour and after 2 hours of walking. Insoles used for experiment are normal insole, insole inserted Arch Support and pad. The electrodes for EMG measurement were set on waist (erector spinae), and thigh (vastus lateralis), calf (gastrocnemius). Evaluations of EMG were analyzed by shift of MF (Median Frequency) and MPF (Mean Power Frequency). Foot Pressure was analyzed by mean pressure of feet and change of walking time. As results, Arch Support insole had larger frequency shift value than that of normal insole. Frequency shift between Arch Support insoles and normal insole showed significant difference on 95% confidence interval. And insole 1 has the highest value of frequency shift. For results of foot pressure, Arch Support insoles show continuous decreasing tendency when comparing with normal insoles by changing of times. Also, insole 1 has the highest decreasing value of foot pressure. Therefore, this study presented that the Arch Support insole can promote muscle activities and improves comfort for a prolonged walking.

• Journal of Korean Medicine Rehabilitation
• /
• v.33 no.4
• /
• pp.15-29
• /
• 2023

Objectives The purpose of this study is to systematically review the effects of Neuromuscular Electrical Stimulation treatment on muscle wasting in cancer patients. Methods Randomized controlled trials (RCTs) were searched from seven online databases (PubMed, Cochrane Library, EMBASE, China National Knowledge Infrastructure, Oriental Medicine Advanced Searching Integrated System, Korean studies Information Service System, Research Information Sharing Service. The selected RCTs were evaluated for methodological quality through the Cochrane RoB. Results A total of 126 articles were identified, and 4 randomized controlled trials were selected for systematic review. In one study, it was found that there were statistically significant improvements in the Health-Related Quality of Life (FACTH&N total score, p<0.001). Additionally, significant effects were observed in measurements that represented the size of the quadriceps muscle (cross-sectional area of Vastus lateralis and Rectus femoris, p=0.004), maximum muscle strength, the twitch response of resistance muscles, and voluntary activation (p<0.001). However, no significant differences were observed between the intervention and control groups in terms of quadriceps muscle strength in two other studies (p>0.05). Lastly, while one study showed no significant differences in muscle fiber characteristics between the two groups, it did report significant improvements in measurements related to mitochondria within muscle tissue and muscle strength in the intervention group (p<0.05). Conclusions Neuromuscular electrical stimulation can be a method used to improve muscle strength in muscle wasting of cancer patients, but it is difficult to see its effects as significant compared to other treatments.

• Archives of Plastic Surgery
• /
• v.39 no.2
• /
• pp.130-136
• /
• 2012

Background : Complex elbow injuries with associated nerve, muscle, or joint injury commonly develop post-inury stiffness. In order to preserve function, joint congruency, elbow stability and durable wound coverage must be achieved in a timely manner. Methods : A retrospective review of patients who underwent orthopaedic fixation followed by free anterolateral thigh (ALT) flap soft tissue coverage was performed. Five patients were identified and included in this study. Results : We present a series of 5 cases managed with this principle. Soft tissue defects ranged in size from $4{\times}9cm$ ($36cm^2$) to $15{\times}30cm$ ($450cm^2$) and were located either posteriorly (n=4) or anteriorly (n=1). Associated injuries included open fractures (n=3) and motor nerve transection (n=2). Wound coverage was achieved in a mean duration of 18.8 days (range, 11 to 42 day). There were no flap failures and no major complications. The mean postoperative active elbow motion was $102^{\circ}$ (range, $45^{\circ}$ to $140^{\circ}$). Conclusions : In our small series we have highlighted the safety and utility of using the free ALT flap in complex elbow injuries. The ALT flap has many advantages which include abundant skin and subcutaneous tissue; vascularised vastus lateralis muscle that was used in our series to obliterate dead space, provide a vascular bed for nerve grafts and combat infection; and, access to fascia lata grafts for reconstruction of the triceps tendon.