• 한국전문물리치료학회지
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• 제13권1호
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• pp.38-46
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• 2006

The purposes of this study were to investigate the median frequency (MDF) between initiation and termination of muscle contraction through surface electromyographic (sEMG) analysis and to propose the basis of clinical treatment for movement problems in early hemiparetic upper limbs. Thirteen patients who had stroke with onset less than 3 months prior to the study and seven control subjects participated in the study. The median frequency in initiation and termination of muscle contraction was recorded from wrist flexor and extensor muscles using the sEMG, with 3 second beeper signals, during maximal isometric wrist flexion and extension. Flexion and extension must be done as quickly and forcefully as possible. The results of the study were as follows: 1. The MDF of the onset and offset sections were significantly lower on the paretic than the nonparetic and control sides. 2. The MDF of the offset section significantly decreased on the paretic and nonparetic sides. Consequently, this study showed that the lowering of the MDF was due to the hemiparetic wrist motor impairment and muscle weakness. These results are also related to Fugl-Meyer motor assessment (FMA) scores in hemiparetic upper limbs. This study also suggests that since muscle weakness of early stroke patients affects the functional decrease of upper limbs, further studies must focus on the treatment to improve muscle agility and muscle fiber recruitment efficiency that can induce the functional recovery correlated to motor control.

• 한국전문물리치료학회지
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• 제16권3호
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• pp.42-49
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• 2009

This study examined the vastus medialis oblique (VMO) and the vastus lateralis (VL) onset time differences (OTD) during quadriceps contraction in different hip positions. Twelve healthy subjects were recruited (four men, eight women). Surface EMG activities of the VMO and VL were measured during a quadriceps strengthening exercise in a long sitting condition and in a sitting at a chair with feet hanging condition. For each condition, subjects were tested in two hip positions (neutral and adduction). The OTD between the two muscles was calculated for each condition, by subtracting the onset time of the VL from the VMO. Therefore, the negative value of OTD represent earlier EMG onset of the VMO compared to the VL. The OTD was not significantly different between the hip neutral and the hip adduction position in the long sitting condition (p=.064). However, the OTD was significantly different between the hip neutral position ($15.83{\pm}109.51$ ms) and hip adduction position ($-5.58{\pm}121.08$ ms) during the sitting at a chair with feet hanging condition (p=.047). The negative OTD value in the hip adduction condition during quadriceps strengthening exercises is the result of earlier onset of the VMO than VL. Therefore, quadriceps contraction in the hip adduction position can prevent the risk of patella lateral tracking. We expect that quadriceps strengthening exercise in the hip adduction position will be a safe way to prevent patellofemoral pain syndrome resulting from abnormal patella lateral tracking.

• 대한골관절종양학회지
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• 제8권2호
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• pp.48-53
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• 2002

상피암의 인접 골격근으로의 직접 전파는 많이 보고되었으나, 골격근으로의 원격전이는 드물고 특히 다발성 전이는 매우 드문 것으로 알려져 있다. 골격근내의 가변적인 혈류량, 근수축이나 난류성 혈류 등과 같은 물리적인 요인, 골격근내의 산성 환경, 젖산, 세포외 기질의 단백분해효소 억제인자 등이 골격근으로의 원격 전이를 억제하는 원인으로 제시되고 있다. 저자들은 최근 다발성 골격근 전이를 동반한 신장암(이행성 상피세포암) 1례를 경험하였기에 이를 보고하는 바이다.

• The Journal of Korean Physical Therapy
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• 제23권1호
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• pp.7-11
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• 2011

Purpose: Driving is essential to maintain independent living status in modern times. Many patients want to know when they can drive again, but it's only possible if they have the ability to control lower extremity muscles. In this study, we compared the effects of velocity on onset time of lower extremity muscles during driving tasks. Methods: Twelve participants (5 male, 7 female) were enrolled. EMGs were used to test the onset time of lower extremity muscles; tibialis anterior, soleus, rectus femoris. To analyze the data, we used two way ANOVA. Results: According to brake pedaling velocity, there was a significant difference in brake response time (p<0.05). Further, when comparing the lower extremity muscles, there was a significant difference in onset time (p<0.05). The order of muscle recruitment was tibialis anterior, rectus femoris, and soleus for achieving maximal velocity, but the order was rectus femoris, tibialis anterior, soleus for achieving submaximal velocity. Conclusion: Brake pedaling velocity has significant effects on onset time of muscle contractions in the lower extremities. We suggested that a future study needs more subjects and more detailed research such as evaluat-ions of visuo-motor coordination and fine motor dexterity.

• 대한물리의학회지
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• 제7권3호
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• pp.319-327
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• 2012

Purpose : This study aimed to identify the asymmetry observed in the rehabilitative ultrasound imaging of lateral abdominal muscle thickness and performance between the affected and unaffected side during the abdominal drawing-in maneuver (ADIM), an exercise used to facilitate activation of selectively TrA to stabilize the trunk prior to limb movement. Methods : The Participants were twenty one patients with post-stroke hemiplegia in this study. Ultrasound imaging was used to measure amount of changes in thickness of the external oblique (EO), internal oblique (IO), transversus abdominis (TrA). A Paired t-test was used to compare relaxed muscle thickness to contracted muscle thickness of all 3 muscles between the affected and unaffected sides. Results : The outcome measures included side to side differences of absolute thickness, contraction ratio among the lateral abdominal muscles. There was no significantly difference in between the affected and unaffected side at rest. But, there was a significantly difference in absolute muscle thickness between the affected and unaffected side of only TrA muscle. Also contraction ratio was a significantly difference between the affected and unaffected TrA muscle. Conclusion : These findings support the asymmetrical activation of TrA muscle during abdominal muscle contraction in patients with post-stroke hemiplegia. Further studies are warranted for confirming this outcome.

• PNF and Movement
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• 제13권1호
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• pp.1-7
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• 2015

Purpose: This study aimed to examine the activity of the shoulder flexor and extensor when hold-relax and contraction-relax techniques were applied with shoulder joint flexion. Methods: The subjects of this study were 15 healthy women. With the shoulder joint flexion at $0^{\circ}$ and $90^{\circ}$, hold-relax and contraction-relax techniques were applied for the same submaximal resistance to measure the activities of the deltoid muscle anterior fiber, deltoid muscle posterior fiber, pectoralis major fiber, and latissimus dorsi muscle with surface electromyography. An independent t-test was conducted in order to compare activities of each muscle according to the two techniques. Results: When the hold-relax and contraction-relax techniques were applied with the shoulder joint flexion at $0^{\circ}$, the activities of the shoulder flexor and extensor were not significantly different, but the activity of the flexor was higher when the contraction-relax technique was applied than when the hold-relax technique was applied. When the hold-relax and contraction-relax techniques were applied with the shoulder joint flexed at $90^{\circ}$, the activities of the shoulder flexor and extensor were not significantly different, but the activity of the extensor was relatively higher than when the flexor was at $0^{\circ}$ Conclusion: When the hold-relax and contraction-relax techniques were applied with the shoulder joint flexion at $0^{\circ}$, the activities of the shoulder flexor and extensor were not significantly different, but the activity of the flexor was higher when the contraction-relax technique was applied than when the hold-relax technique was applied. When the hold-relax and contraction-relax techniques were applied with the shoulder joint flexed at $90^{\circ}$, the activities of the shoulder flexor and extensor were not significantly different, but the activity of the extensor was relatively higher than when the flexor was at $0^{\circ}$.

• 대한통합의학회지
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• 제7권1호
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• pp.19-26
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• 2019

Purpose : The aim of this study was to investigate the effects of the abdominal draw-in (ADI) exercise on the onset times of the gluteus maximus (GM) and erector spinae (ES) as well as the pelvic anterior tilt angle during prone hip extension (PHE). Methods : A total of 24 female adults were divided into two groups: those with normal abdominal muscles (n=12) and those with weak abdominal muscles (WAM; n=12). Before the intervention, the onset times of the GM and ES along with the pelvic angle during PHE were measured. Subsequently, the participants conducted the ADI exercise for 10 minutes. After conducting the ADI exercise, the onset times and the pelvic angle were re-measured. Results : In the pre-intervention comparison between the two groups, the WAM group showed faster ES onset times and higher pelvic angle than the normal group (p<0.05). In the WAM group, the ES onset times were significantly delayed after the ADI exercise (p<0.05). In both groups, the pelvic angle was significantly decreased after the ADI exercise (p<0.05). The decrease in the pelvic angle was significantly greater in the WAM group than in the normal group (p<0.05). The GM onset time was found to be not significant in all comparisons (p>0.05). Conclusion : Therefore, it can be concluded that after performing the ADI exercise, the pelvic anterior tilt during PHE is decreased in normal women and those with WAM, especially in the WAM group, suggesting that the ADI exercise can reduce the compensatory pelvic anterior tilt more effectively by delaying the ES onset times.

• PNF and Movement
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• 제12권1호
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• pp.19-25
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• 2014

Purpose: To investigate the effect of action observation training on the muscle onset time and symmetrical use of rectus femoris(RF) and gastrocnemius medialis(GCM) during sit-to-stand (STS). Methods: Sixteen patients with stroke entered a single-blind trial and were randomly assigned to the experimental(Action) or control(Landscape) groups. Those in the Action observation group watched video clips showing specific movement and strategies to STS, wheas those in the control group watched video clips of static pictures showing differnet landscapes. All patients was measured the EMG data in the STS on the affected side and unaffected side. The EMG data were collected from RF and GCM while performing the STS task. The EMG onset time and onset time ratio for the RF and GCM were calculated by dividing the EMG onset time of RF and GCM action on the affected side by these on the unaffected side. Results: Onset time of affected side RF, GCM was significantly faster action observation training group than control group(p<.05). But interventions before and after the symmetry did not show a significant increase. Conclusion: There findings suggest that action observation training has a positive effect on the muscle onset time shortened during STS tasks.

• 정형스포츠물리치료학회지
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• 제14권2호
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• pp.55-64
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• 2018

Purpose : The purpose of this study was to investigate the effect of the sprinter and skater combined patterns on muscle contraction onset time and muscle activation of body stabilizing muscles. Method : Our study included young and healthy men in their 20s. The participants used the sprinter and skater combined patterns of the proprioceptive neuromuscular facilitation (PNF) methods to measure muscle activation and muscle contraction onset time of the trunk muscles. To measure muscle contraction onset time and muscle activation, electrodes were attached to the rectus abdominis (RA), external oblique (EO), internal oblique (IO), and erector spinalis (ES) regions. Significant differences were identified using a paired t-test and a one-way analysis of variance (ANOVA) analysis. Result : In the sprinter combined pattern, the muscle with the fastest onset time of contraction was the RES, and that with the slowest was the RRA (p<.001). In the skater combined pattern, the muscle with the fastest onset time of contraction was the LES, and that with the slowest was the LRA (p<.001). In the sprinter combined pattern, the REO and LIO presented medium muscle contraction onset times (p<.001). In the skater combined pattern, the LEO and RIO presented medium muscle contraction onset times (p<.001). Conclusions: Based on these results, these patterns could be used as exercise methods for the elderly with delayed proactive response speeds of the body stabilization methods due to imbalances in body stabilizing muscles or limbs movement.

• PNF and Movement
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• 제18권3호
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• pp.375-382
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• 2020

Purpose: The purpose of this study was to investigate the muscle contraction onset time characteristics of the gluteus maximus, semitendinosus, and biceps femoris muscles at different knee flexion angles in individuals with shortened or over-lengthened hamstrings performing prone hip extension. Methods: Twenty-six participants were divided into a hamstring shortened group (n = 12) and hamstring lengthened group (n = 14). Wireless surface electromyography was used to verify the muscle onset time of the gluteus maximus, semitendinosus, and biceps femoris when performing prone hip extension at different knee flexion angles. Results: There were significant differences in the muscle onset times of the semitendinosus and biceps femoris between the hamstring shortened group and hamstring lengthened group (p < 0.05). In addition, there was a significant difference in the muscle contraction onset times among of the gluteus maximus, semitendinosus, and biceps femoris muscles when performing prone hip extension at a knee flexion of 90° in the hamstring shortened group (p < 0.05) and a knee flexion angle of 0° in the hamstring lengthened group (p < 0.05). Conclusion: In all groups, there was no effect on the onset time of the gluteus maximus muscle according based on the knee angle. In addition, the knee flexion angles affected the onset time of the muscle contraction of the gluteus maximus muscle in the hamstring shortened group and hamstring lengthened group with an abnormal length of the hamstring muscle.