• Journal of Advanced Technology Convergence
• /
• v.2 no.2
• /
• pp.31-38
• /
• 2023

This study compares the correlation between muscle thickness (abdominal, quadriceps muscle) and how the muscle thickness affects the static balance when the static balance is measured in a standing position. The subjects of study were to select 29 subjects to find out what relationship muscle thickness had on the static balance when measuring muscle thickness and static balance. rectus femoris muscle thickness showed a significant correlation in statically balanced weight distribution index. In this study, only healthy men in their twenties were selected, and the results could not be generalized to other age groups. As a limitation of this study, muscle strength and peripheral vision were not measured, so it seems difficult to express the accuracy of the study and generalize the results. In future studies, the number of subjects and muscle strength should be measured to proceed with the study.

• PNF and Movement
• /
• v.9 no.1
• /
• pp.47-54
• /
• 2011

Purpose : The purpose of this study was to investigate muscle activity of affected lower extremity by unaffected lower extremity exercise and tried to examine muscle activity of affected lower extremity of hemiplegic patients were caused by stroke according to wearing single strap hemisling or non-wearing. Methods : We measured muscle activity of affected lower extremity when wearing single strap hemisling to affected lower extremity or non-wearing according to unaffected lower extremity used MP 150 Eletromyogram. Results : 1) Muscle activity of gluteus medius muscle was the highest D1 before wearing single strap hemisling. 2) Muscle activity of hamstring muscle was the highest D3 after wearing single strap hemisling. 3) Muscle activity of quadriceps muscle was the highest D5 after wearing single strap hemisling. 4) Muscle activity of tibialis anterior muscle was the highest D1 after wearing single strap hemisling. 5) Muscle activity of soleus muscle was the highest D2 before wearing single strap hemisling. Conclusion : Wearing single strap hemisling of hemiplegic patients had effect on muscle activity of gluteus medius but didn't effect gluteus medius, hamstring, quadriceps, tibialis anterior muscle and soleus muscle.

• Journal of Korean Physical Therapy Science
• /
• v.15 no.4
• /
• pp.19-26
• /
• 2008

Background: This study examines the changes in muscular strength and muscle fatigue substances when taping treatment is applied in squat exercise and treadmill exercise, in which quadriceps femoris muscles are used frequently so as to clarify the effects of taping as an aid of exercise ability improvement. Methods: 20 healthy male adults in their 20's participated in the study, in which tapes were put on their quadriceps femoris muscles, and various variables as the indicator of muscular strength and muscle fatigue substances were measured by means of the measuring tool before and after exercises. Results: the following conclusion was drawn up: 1. In exercise using muscular strength of the right knee extension, the reduction of muscular strength after exercise of the taping group showed significant statistical difference from that of the non-taping group. 2. In exercise using muscular strength of the lower limbs, the reduction of blood Glaucos after exercise of the taping group showed significant statistical difference from that of the non-taping group. 3. In exercise using muscular strength of the lower limbs, the value of lactic acid after exercise of the taping group showed significant statistical difference from that of the non-taping group. Conclusion: Therefore, the results of this study demonstrate that the application of taping treatment in sports activity or daily life where quadriceps femoris muscles are used a lot can have positive effects on the improvement of muscular strength and relief of muscle fatigue.

• Journal of The Korean Society of Integrative Medicine
• /
• v.6 no.1
• /
• pp.7-14
• /
• 2018

Purpose : The purpose of this study was to confirm changes in the muscle activity of the quadriceps femoris with changes in the ankle and hip joint angles during the transition from sitting to standing. Method : Twenty-five healthy 20-30-year-old women participated in the study. The subjects performed standing-up movements in four positions: standard posture (hip = $90^{\circ}$/ankle = $0^{\circ}$); posture on a decline board (hip > $90^{\circ}$/ankle < $0^{\circ}$), posture on a footboard (hip > $90^{\circ}$/ankle = $0^{\circ}$); and posture on a decline board with a higher chair (hip = $90^{\circ}$/ankle < $0^{\circ}$). Then, the muscle activities of the rectus femoris, vastus medialis and vastus lateralis were measured using surface electromyography. Result : The muscle activities of the rectus femoris, vastus medialis and vastus lateralis in the footboard application were statistically significantly higher than in the application of the decline board with a higher chair. Conclusion : This study confirms that the flexion of the hip joint has a greater effect than the plantar flexion of the ankle joint on the muscle activity of the quadriceps during a sit-to-stand movement.

• Journal of the Korean Society of Physical Medicine
• /
• v.15 no.4
• /
• pp.121-129
• /
• 2020

PURPOSE: This study aimed to propose an exercise technique that helps improve the skeletal muscle function while suppressing the symptoms of respiratory distress, by mediating squat exercises in whole-body vibration for patients with severe COPD, and comparing the post intervention pulmonary function and activity of quadriceps. METHODS: Totally, 21 patients with severe COPD were randomly assigned to two groups through clinical sampling: experimental group I included 11 patients (Squat exercise combined with whole-body vibration exercise), and experimental group II included 10 patients (Only squat exercise). Before intervention, we measured pulmonary function using a pulmonary function tester, muscle activity of quadriceps using surface EMG, and gait ability using the 6MWT. RESULTS: Comparison of intra-group changes in both experimental groups showed a significant increase in the activity of rectus femoris, vastus medialis, and vastus lateralis, and also in the 6MWT. Intra-group comparisons also revealed significant difference in the activity of rectus femoris, vastus medialis, and vastus lateralis (p < .05). CONCLUSION: Squat exercise combined with whole-body vibration significantly increased the activity of the quadriceps muscle, suggesting that this intervention helps maintain the function of skeletal muscles and prevent muscle atrophy. Therefore, studies to develop protocols using whole body vibration in clinical practice as an exercise method can safely be performed in severe COPD patients, as considered necessary.

• Journal of the Korean Society of Physical Medicine
• /
• v.16 no.1
• /
• pp.23-31
• /
• 2021

PURPOSE: This study was conducted to identify the effects of altering foot position on quadriceps femoris including vastus medialis obliques (VMO), vastus lateralis (VL) and rectus femoris (RF) activation during wall squat exercises. METHODS: All subjects (n = 15) were selected and randomly performed three kinds of wall squats: 1) GWS (General Wall Squat), 2) WSS1/4 (Wall Squat Short 1/4), and 3) WSS1/2 (Wall Squat Short 1/2). Each subject completed all three kinds of wall squatting exercises at three different times and recorded the muscle activity data of vastus medialis obliques, vastus lateralis and rectus femoris. RESULTS: Compared with GWS exercise, VMO and RF muscle activity significantly increased under WSS1/2 exercise (p < .05), while only RF muscle activity significantly increased under WSS1/4 exercise (p < .05). CONCLUSION: The results of the present study indicate that moving the foot toward the wall during wall squats has a positive effect on quadriceps activation. The exercise of wall squat short can not only be used as the lower limb muscle strengthening training for normal people, but also as the recovery training for patellofemoral pain syndrome patients in the rehabilitation stage. Besides, Anterior cruciate ligament patients can also try this exercise according to the advice of doctors and therapists.

• Korean Journal of Applied Biomechanics
• /
• v.22 no.2
• /
• pp.201-208
• /
• 2012

The purpose of this study was to investigate the effect of leg extension exercises performed on outdoor resistance exercise machines on knee extension muscle strength and quadriceps muscle group cross sectional area (CSA) in elderly women. Two groups were recruited for this study, including an exercise group (EG: n=13, $71.38{\pm}2.79$ yrs) and a control group (CG: n=5, $73.4{\pm}5.94$), In all subjects, maximum isometric and isokinetic muscle strength of knee flexion and extension were measured using an isokinetic dynamometer (Cybex(R) Humac Norm Testing & Rehabilitation System, USA). Quadriceps muscle group CSA were measured using MRI (Philps, Intera 1.5 T, NE Netherlands). The results of this study showed that post-intervention isometric knee extension peak torque value were higher than pre-intervention measures in the EG. However, the EG did not show improvement in quadriceps muscle group CSA, Also, no differences in the shift of optimal knee joint angle were observed between pre and post-intervention exercise. Outdoor leg extension exercise showed small increases in muscle strength in comparison to other resistance training exercises. The results of this study suggest that because outdoor leg extension exercise machines lack a progressive loading mechanism, significant increases in muscle strength may not be obtained.

• Physical Therapy Korea
• /
• v.13 no.4
• /
• pp.1-9
• /
• 2006

The purpose of this research was to analyze the effects of the increase of the femoral anteversion angle on the unbalanced quadriceps femoris muscle causing the increase of the valgus force on the knee joints and patellofemoral pain syndrome by comparing with the group that shows the smaller femoral anteversion angle. The method for the research was to compare the femoral muscle's activity while the subjects were maintaining the knee joint flexed isometrically for 10 seconds. The evaluation tool for femoral muscle's activity was QEMG-4 (model LXM 3204). The results were as followings. Firstly, in case of the experimental group, the muscle strength of the vastus lateralis muscle was strong while the rectus femoris and vastus medialis were weak. In these facts, we can see the statistically meaningful difference in vastus medialis muscle activity. Secondly, in the muscle activity analysis for vastus lateralis and medialis of the two groups, we could see the vastus lateralis muscle was strong in anteversion wider for experimental group while the vastus medialis muscle contracted far more stronger in anteversion smaller for control group. From these results, we can see the significant differences in muscle recruitment between the two groups. Above results show that if the anteversion becomes wider, vastus medialis muscle will become seriously weaker, on the other hand, vastus lateralis act stronger.

• Journal of Digital Convergence
• /
• v.12 no.7
• /
• pp.365-370
• /
• 2014

The present study was aimed to comprehend the effect of the Russian current stimulation on the muscular performance and activity of quadriceps femoris muscle of the convalescent patient after the leg fracture.This study conducted test based on 20 patients after leg fracture. Russian current was applied for six weeks as three times in a week, between January 9, 2013 and 15 March 16, 2013. The electromyogram was used to measure the muscle activity of the quadriceps femoris, and the isokinetic equipment was used to measure the muscular performance. The muscular performance difference by duration depending on the application of the Russian current showed the significant increase in all muscular performances. The activity of all muscles of the quadriceps femoris muscle by duration showed significant increase. These results showed that the Russian current can be the effective treatment method for enhancing the muscular strength of the weakened lower limbs muscle due to the problem such as the leg fracture.

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