• The Journal of Korean Physical Therapy
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• 제32권4호
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• pp.228-232
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• 2020

Purpose: This study examined the electromyography (EMG) activity of the abdominal muscles and the ratio of the oblique abdominal muscle activity to the rectus abdominis muscle during a single-leg holding position with isometric shoulder abduction (SLHISA) in the supine position on a foam roller. Methods: Nineteen healthy males were recruited to the study. Each subject was asked to lay on a round foam roller and perform singleleg (nondominant) holding with contralateral shoulder abduction to one of three angles (45°, 90°, or 135°) in random order. The surface EMG signals of the bilateral rectus abdominis (RA), external oblique abdominis (EO), and combined internal oblique abdominis (IO) and transverse abdominis (TrA) muscle were collected during the tasks. The EO/RA and (IO & TrA)/RA ratios were determined using surface EMG. One way repeated measure ANOVA with three SLHISAs was used to assess the significant abdominal muscle EMG activity and the ratio of the oblique abdominal muscles activity to the RA muscle. The statistical significance level was p<0.05. Results: The results were as follows. The SLHISA 135° showed significantly higher EMG activity of both RAs, left EO, and right IO & TrA muscles (p<0.05). The right EO and left IO and TrA muscles/RA were significantly different among the SLHISA angles. The SLHISA 45° showed a significantly greater ratio of right EO/RA and left IO & TrA/RA (p<0.05). Conclusion: SLHISA on a foam roller is useful for lumbopelvic stabilization exercise by increasing the activity and recruiting a specific pattern of the oblique abdominal muscle.

• The Journal of Korean Physical Therapy
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• 제32권5호
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• pp.273-276
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• 2020

Purpose: The purpose of this study was to investigate the effects of the resistance conditions on the electromyography (EMG) activity ratio of vastus medialis oblique (VMO) and vastus lateralis (VL) muscle during partial lunge exercise in healthy subjects in order to suggest the basic data of exercise intervention for such as patients with patellofemoral pain syndrome (PFPS). Methods: The participants of this study were healthy twenty two people with no knee pain, limitation of motion and past history of operation at lower extremity. The participants performed three types of lunge 1) no resistance, 2) anterolateral 45° resistance and 3) lateral 90° respectively. The EMG activity of the VMO and VL were recorded by surface EMG and the measured data normalized by the %MVIC value was analyzed by repeated measured ANOVA. Results: The results showed that the VMO/VL EMG activity ratio during lunge with anterolateral 45° resistance was significantly higher than with no resistance and lateral 90° resistance (p<0.05). There was no significant difference in VMO, VL, and VMO/VL muscle activity between male and female subjects (p>0.05). Conclusion: This study suggests that partial lunge exercise with anterolateral 45° resistance can increase the VMO/VL muscle activity in healthy subjects. This result could be used as basic data to develop therapeutic exercise programs such as PFPS patients.

• 한국전문물리치료학회지
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• 제20권4호
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• pp.1-8
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• 2013

This study analyzes how different knee flexion angles affect the abdominal and pelvic muscle activity during supine bridging. Twenty healthy subjects participated in the study. We used surface electromyography (EMG) to measure how three different knee flexion angles ($100^{\circ}$, $70^{\circ}$, and $40^{\circ}$) affected the activity of the transverse abdominis/internal oblique (TrA/IO), external oblique (EO), biceps femoris (BF), rectus femoris (RF), and gluteus maximus (GM) muscles on the dominant side during supine bridging. The one-way repeated analysis of variance (ANOVA) was used to determine the statistical significance of TrA/IO, EO, BF, RF and GM muscle activity and the GM/BF activity ratio. For the TrA/IO, EO, BF, and GM muscles, supine bridging with different knee flexion angles resulted in significant differences in abdominal and pelvic muscle activity. For the TrA/IO muscles, the post-hoc test demonstrated that muscle activity significantly increased at $40^{\circ}$ compared to $70^{\circ}$; however, there were no significant differences between $100^{\circ}$ and $70^{\circ}$ or $100^{\circ}$ and $40^{\circ}$. For the EO muscle, the post-hoc test demonstrated that muscle activity significantly increased at $40^{\circ}$ compared to $100^{\circ}$ and $70^{\circ}$; no significant difference was observed between angles $100^{\circ}$ and $70^{\circ}$. For the BF muscle, the post-hoc test demonstrated that muscle activity significantly increased according to the knee flexion angle ($40^{\circ}$ > $70^{\circ}$ > $100^{\circ}$). For the GM muscle, the post-hoc test demonstrated that muscle activity significantly increased according to the knee flexion angle ($100^{\circ}$ > $70^{\circ}$ > $40^{\circ}$). However, for the RF muscle, there was no significant difference. Additionally, the GM/BF activity ratio significantly increased according to the knee flexion angle ($100^{\circ}$ > $70^{\circ}$ > $40^{\circ}$). From these results, we can conclude that bridging with a knee flexion of $100^{\circ}$ can strengthen the GM muscle, whereas bridging with a knee flexion of $40^{\circ}$ is recommended to strengthen the IO, EO, and BF muscles. We can also conclude that knee flexion angles should be modified during supine bridging to increase the muscle activity of different target muscles.

• PNF and Movement
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• 제17권1호
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• pp.11-18
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• 2019

Purpose: This study verifies the muscle activity around the amputation site during proprioceptive neuromuscular facilitation (PNF) pattern exercise for the upper extremities on the non-amputated part in upper extremity amputees and provides basic data on effective exercise around an amputation site. Methods: Manual resistance was applied to the PNF upper extremity pattern of the non-amputated part to generate muscle activity around the amputation site. The resistance was adjusted to an intensity that could cause maximal isometric contraction. The muscle activity of the amputation site and the non-amputated part was measured using a surface electromyogram for the upper trapezius, middle trapezius, infraspinatus, serratus anterior, and pectoralis major. Results: During the scapular exercise in the painless range, the amputated side showed significantly lower muscle activity and a lower muscle contraction ratio compared with the non-amputated side. During the PNF pattern exercise in the painless range, the amputated side showed lower muscle activity and a lower muscle contraction ratio compared with the non-amputated side. When the direct scapular exercise of the amputated side was compared with the PNF pattern exercise of the non-amputated side, their muscle contraction ratios were similar. Conclusion: This study confirmed the effectiveness of the PNF pattern exercise of the non-amputated part as a way to indirectly train the injured site with no pain for rehabilitation of patients with serious body injuries, such as amputation. It is necessary to develop effective exercise programs for the rehabilitation of the amputation site based on the results of this study.

• 대한물리의학회지
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• 제17권1호
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• pp.127-137
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• 2022

PURPOSE: This study sought to evaluate muscle activity and foot pressure during gait, and balance in female college students with genu valgum. METHOD: Participants were assigned based on their Q-angle to genu valgum group greater than 20° (GVG, n = 12), unilateral genu valgum group greater than 20° (UVG, n = 11), and control group (CON, n = 13). All subjects were evaluated for balance (Trace length, C90 area, C90 angle, and the Romberg test), muscle activity (gluteus medius; GM, tensor fasciae latae; TFL, vastus medialis; VM, vastus lateralis; VL, biceps femoris; BF, gastrocnemius; GCM and tibialis anterior; TA) and foot pressure (F/F ratio, R/F ratio, Hallux, 2~5 toe, 1st MT, 2~4 MT, 5th MT, Midfoot, M/heel, and L/heel) during gait. RESULTS: Romberg test showed significantly increased loss of balance in the UVG group compared with the CON. In the forward position, the imbalance was significantly increased in the UVG and GVG groups compared to the CON. Muscle activity of VL, GCM, and TA significantly increased in the GVG group compared with the CON. Static foot pressure, 1st MT significantly increased in the GVG compared to the CON group. The 5th MT significantly decreased in the CON compared with the GVG group. The R/F ratio significantly decreased in the GVG compared to the CON group. In dynamic foot pressure, the 2~5 toe significantly increased in the GVG compared with the UVG group. The left 5th MT significantly decreased in the UVG compared with the CON and GVG groups. CONCLUSION: These results indicate that genu valgum has a negative effect on balance, muscle activity, and foot pressure during gait in female college students.

• 한국전문물리치료학회지
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• 제17권4호
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• pp.8-15
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• 2010

This study was designed to investigate the effect of different hand positions on scapulothorcic muscle activities during push-up plus exercises. Fourteen healthy males performed push-up plus exercises under three conditions (neutral, $90^{\circ}$ internally rotated, and $90^{\circ}$ externally rotated hand positions), during which the activities of the serratus anterior, pectoralis major, and upper trapezius muscles were recorded using surface electromyography. The statistical significance at three different hand positions was tested by repeated one-way ANOVA. The mean activities of the serratus anterior increased and the mean activities of the pectoralis major decreased in the order of neutral hand position, internally rotated hand position, and externally rotated hand position. There was a significant difference during push-up plus between neutral and externally rotated hand positions as well as in the serratus anterior/pectoralis major activity ratio (p<.0.5). However, no significant differences were found in the activity of the upper trapezius muscle or the serratus anterior/upper trapezius activity ratio. We suggest that the push-up plus exercise performed in the externally rotated hand position could a beneficial strategy for selective strengthening of the serratus anterior muscle, while minimizing the activity of the pectoralis major muscle.

• 한국전문물리치료학회지
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• 제21권3호
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• pp.1-10
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• 2014

The aim of this study was to investigate the effect of hip external rotation angle on pelvis and lower limb muscle activity during prone hip extension. Sixteen healthy men were recruited for this study. Each subject performed an abdominal drawing-in maneuver (ADIM) in a prone position, and extended the dominant hip at three different hip external rotation angles ($0^{\circ}$, $20^{\circ}$, $40^{\circ}$) with a $30^{\circ}$ hip joint abduction. Activity of the gluteus maximus (G Max), gluteus medius (G Med), and hamstring (HAM) and the G Max/HAM and G Med/HAM ratios were determined with surface electromyography (EMG). The EMG signal was normalized to 100% maximum voluntary isometric contractions (MVICs) and expressed as %MVIC. Data were analyzed by one-way repeated analysis of variance (alpha level=.05) and the Bonferroni post hoc test. Significant differences in G Max and G Med muscle activity were noted among the three different hip external rotation angles. G Max muscle activity increased significantly at both $40^{\circ}$ (p=.006) and $20^{\circ}$ (p=.010) compared to a $0^{\circ}$ hip external rotation angle. G Med muscle activity increased significantly at $20^{\circ}$ (p=.013) compared to a $40^{\circ}$ hip external rotation angle. The G Max/HAM activity ratio increased significantly at both $40^{\circ}$ (p=.004) and $20^{\circ}$ (p=.014) compared to a $0^{\circ}$ hip external rotation angle. The G Med/HAM activity ratio increased significantly at $20^{\circ}$ (p=.013) compared to a $40^{\circ}$ hip external rotation angle. In conclusion, $40^{\circ}$ and $20^{\circ}$ hip external rotation angles are recommended to increase G Max activity, and $20^{\circ}$ hip external rotation is advocated to enhance G Med muscle activity during prone hip extension with ADIM and $30^{\circ}$ hip abduction in healthy subjects.

• The Journal of Korean Physical Therapy
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• 제32권6호
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• pp.378-382
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• 2020

Purpose: This study aimed to examine the effects of forward head posture on the flexion-relaxation ratio (FRR) and muscle activity during sustained neck flexion and to investigate the correlation between craniovertebral angle and FRR. Methods: Nineteen subjects participated in this study and were allocated to a forward head posture (FHP) group or a non-forward head posture (NFHP) group. Craniovertebral angle (CVA) and FRR were measured in all subjects, and all participants performed a standardized cervical flexion-extension movement in two phases: Phase I, sustained cervical full flexion for 5s; and Phase II, cervical extension with the return to the starting position for 5s. The value of CVA has calculated three times, and the value of FRR was measured three times in order to obtain the mean value. Results: FRR values in the FHP and NFHP group were significantly different (p<0.05). Phase I was significantly different, but the Phase II was not significantly different between the FHP and NFHP group (p>0.05). There was a significant correlation between the muscle activity of Phase I and CVA (p<0.05). However, FRR and the muscle activity of the Phase II were not a significant correlation with the CVA (p>0.05). Conclusion: FHP increases the muscle activity of the cervical erector spinae during sustained neck flexion and reduces FRR, which can cause fatigue in the cervical erector spinae. In addition, for those with a smaller CVA, muscle activity of the cervical erector spinae is increased during sustained neck flexion, which can increase neck muscle tension.

• 대한정형도수물리치료학회지
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• 제16권1호
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• pp.26-36
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• 2010

Purpose: The study compared the muscle activity and ratio of upper trapezius (UT) to lower trapezius (LT) activity between acute and chronic whiplash-associated disorder (WAD) patients. Methods: Twelve healthy (male: 7), 14 acute WAD (male: 7), and 11 chronic WAD (male: 3) volunteers participated in this study. Electromyography using a surface EMG recorded the activity of the upper trapezius and lower trapezius of both shoulders (dominant and non-dominant) during $120^{\circ}$ elevation when standing and shoulder depression when sitting. The testing order was selected randomly. Subjects were asked to maintain each experimental position for 5 seconds at end range. EMG activity was normalized using the maximal voluntary isometric contraction (MVIC) elicited using a manual muscle-testing technique. One-way repeated measures analysis of variance (ANOVA) was used to compare the average root mean square (RMS) value of EMG activity for each condition. Results: The EMG activity of the dominant UT for chronic WAD subjects was significantly higher than for acute WAD subjects during $120^{\circ}$ elevation (p<.05). The EMG activity of the dominant LT for acute WAD subjects was significantly lower than for the control group (p<.05) during $120^{\circ}$ elevation. The EMG activity of the dominant LT for WAD patients was significantly lower than for the control group during shoulder depression (p<.05), and the chronic WAD patients scored significantly the lowest (p<.01). The dominant UT/LT for chronic WAD patients was significantly higher than the ratio for acute WAD subjects during shoulder depression (p<.05); this result was higher than for the control group (p<.01). The non-dominant UT/LT (ratio) for chronic WAD patients was significantly higher than the ratio for acute WAD subjects during shoulder depression (p<.05). Conclusion: The UT for chronic WAD subjects was hyperactive when compared to the acute WAD subjects, and the was hypoactive for both acute and chronic patients, therefore intra-trapezius imbalance was more prevalent during shoulder depression.

• Physical Therapy Rehabilitation Science
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• 제10권2호
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• pp.90-97
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• 2021

Objective: The purpose of this study was to find out how the back instability during clam exercise (CE) causes changes in pelvic rotation and hip joint abductor muscle activity, and to find out the effects with different methods of application of pressure biofeedback. Design: Comparative study using repeated measures. Methods: Each subjects performed the clam exercise (CE) without pressure biofeedback, the clam exercise with pressure biofeedback applied to the back (CE-PBU to back), and the clam exercise with pressure biofeedback applied to the side (CE-PBU to side). The amount of pelvic rotation was measured using myomotion. And the muscle activity of the muscle gluteus medius and the tensor fasciae latae was measured using EMG device. One-way repeated measures ANOVA followed by the Bonferroni post test were used to compare the EMG activity in each muscle and pelvic rotation angle during the CE, CE-PBU to back, CE-PBU to side. Results: The amounts of pelvic rotation was the lowest in CE-PBU to back (p< 0.05) and the ratio of muscle activity of the muscle gluteus / tensor fasciae latae was the highest in CE-PBU to back (p< 0.05). Conclusions: It is thought that, in order to stabilize the waist-pelvis and increase hip joint muscle strength in subjects with back instability, applying clam exercise with pressure biofeedback applied to the lower back is effective in improving waist-pelvic movements and selectively strengthening the muscle gluteus medius.