The purpose of this study was to determine the effect of the changes that occur in the leg muscle activity of unstable surface with different levels of air pressures. Three groups of college students have been placed randomly on unstable surfaces with different air pressures at group 1.0 psi (=36), group 1.4 psi (=40), and group 1.8 psi (=40). Using surface electromyography, the recruitment of the tibialis anterior, peroneus longus, and the gastrocnemius was measured. Maximal voluntary isometric contraction was measured at the different air pressures based on the manual muscle test, then normalizing the value to %maximal voluntary isometric contraction (%MVIC). The tibialis anterior muscle activity was significant change from the unstable surface with difference levels of air pressures between group 1.0 psi and 1.8 psi and between group 1.4 psi and 1.8 psi. peroneus longus muscle activity was significant changes in muscle activity occurred between 1.0 psi and 1.4 psi group and between 1.0 psi and 1.8 psi group. Gastrocnemius muscle activity was significant change in muscle activity occurred between 1.0 psi and 1.4 psi group and between 1.0 psi and 1.8 psi group. In conclusion it identify that 1.0 psi group is most effective on muscle activity than the other groups. These suggest that the rehabilitation or strengthening of patients with ankle injuries, balance exercise with low air pressure like 1.0 psi can be more effective.

The aim of this study is to compare the effect of abdominal drawing-in maneuver (ADIM) on lower trapezius (LT), serratus anterior (SA), and erector spinae (ES) muscle activity during arm lifts in prone and standing positions. Twenty healthy subjects were recruited, and NoraxonTeleMyo 2400T was used to collect electromyographic signals from the LT, SA, and ES muscles. A two-way repeated analysis of variance (ANOVA) used a significance level of .05. If a significant interaction was found, pairwise comparisons were performed with a Bonferroni adjustment (.05/4=.013). The results of the study were as follows: 1) In LT, no significant ADIM by position interaction was found (=.356, p=.558). There was a significant main effect for ADIM. LT muscle activity with ADIM was significantly greater compared with muscle activity without ADIM (=82.863, p<.001). There was also a significant main effect for position. LT muscle activity in the prone position was greater compared with muscle activity in the standing position (=116.401, p<.001). 2) In SA, significant ADIM by position interaction was found (=8.687, p=.008). There were significant differences in all pairwise comparisons. The greatest SA muscle activity was observed in the standing position with ADIM. 3) In ES, significant ADIM by position interaction was found (=122.473, p<.001). The lowest ES muscle activity was elicited in the standing position with ADIM. Based on these results, ADIM is advocated in the prone position to increase LT muscle activity. In addition, it is concluded that arm lifts in the standing position with ADIM offer the most favorable combination for reducing ES muscle activity and increasing SA muscle activity.

This study was performed to compare the muscle activity of lumbar stabilizers between stoop and semi-squat lifting techniques at different lifting loads. Twenty healthy subjects (9 males, 11 females) were recruited for this study. Muscle activity of external obliques (EO), internal obliques (IO) and lumbar multifidus (LM) muscle was measured by surface electromyography during stoop and semi-squat lifting at different lifting loads (10%, 20%, and 30% of the subject's body weight). A one-way repeated measure ANOVA was applied. The results showed that EMG activity of EO was significantly increased with a load of 30% of body weight compared to 10% and 20% of body weight in both lifting techniques (p<.05). Muscle activity of LM was significantly increased in 20% compared to 10% and 30% compared to 10% of subject's body weight in stoop lifting and the muscle activity of LM was significantly increased in 20% compared to 10%, 30% compared to 20%, and 30% compared to 10% of the subject's body weight in semi-squat lifting (p<.05). However, there was no significant difference in activity of IO according to lifting loads in both lifting techniques. There were no significant differences in muscle activity of EO, IO, and LM between stoop and semi-squat technique (p>.05). Therefore, the results of this study suggested that the EO can contribute to increase the lumbar stability during stoop and semi-squat lifting at 30% of body weight rather than at lower loads, and the LM seems to act as counteractor to imposed loads during stoop and semi-squat lifting with increasing loads.

The purpose of this study was to compare the muscle activity of the abdominal and lumbar multifidus during unilateral prone hip extension on the floor and on a round foam roll. Fifteen healthy participants were recruited. They were instructed to perform a unilateral hip extension on the floor and on a round foam roll in the prone position. Surface electromyography (EMG) signals were recorded from bilateral lumbar multifidus (LM), external oblique (EO), and internal oblique (IO) muscles. A paired t-test was used to compare muscle activity, with the level of significance set at =.05. The results showed that bilateral LM, EO, IO EMG activity during right-hip extension on a round foam roll was greater than that on the floor, and EMG activity of bilateral LM, right EO, and left IO during left-hip extension on a round foam roll was greater than that on the floor (p<.05). These findings suggest that the unilateral hip-extension exercise on a round foam roll can be used to activate the lumbar multifidus and abdominal oblique muscles and causes a different increasing pattern between the two lifting sides.

The purpose of this study was to assess the influence of scapular alignment on the electromyographic (EMG) activity of the trapezius in people with a short pectoralis minor muscle. For the study, we recruited 15 volunteers who had positive results for short on a pectoralis minor muscle length test. We measured the EMG activity of the upper, middle and lower trapezius muscles. The participants lifted their dominant arm to ear level with the thumb up toward the ceiling in the prone position on a table with the shoulder at a flexion angle of 180 degrees and a horizontal abduction angle of 120 degrees. Scapula was manually aligned by an experienced physical therapist prior to arm lift for the scapular alignment condition. A paired t-test was used to compare the effects of scapular alignment on the EMG activity of the trapezius muscles. The EMG activity of the lower trapezius muscle was significantly increased during the test with the scapular alignment compared to that without scapular alignment (p<.05), while the upper trapezius and middle trapezius exhibited no significant difference between the two conditions (p>.05). The findings of this study suggest that a scapular alignment may alter the recruitment of the lower trapezius muscle during arm lifting in the prone position in people with a short pectoralis minor muscle.

The purpose of this study was to analyze lower limb muscle activity and 3D motion analysis according to change foot arch height during walking. We selected 9 young and healthy people who have been normal foot. And we selected 7 young and healthy people who have been flatfoot. So, people were divided into 2 groups and walked platform during 2 minutes twice for checked by 3D motion analysis. These data were characterized by EMG measurements of three muscles( tibialis anterior, medial and lateral gastrocnemius) while they were walking. The collected data were analyzed by Independent t test using the SPSS statistics program(Ver 12.0). In foot arch change, there were no significant difference in three muscles 3D motion analysis also found that there were no significant difference in joint angles. In this study was to analyze lower limb muscle activity and 3D motion analysis according to change foot arch, but there were no significant difference in 6 muscles neither joint angles.

The purpose of this study was to investigate the effect of the two different types of chairs on trapezius muscle activation during dictation tasks. Seventeen university students, each of whom were within standard deviation of the mean Korean standard body size, voluntarily participated in this study. Surface electromyography was used to collect electrical signals from both the upper and lower trapezius muscles. Amplitude Probability Distribution Function (APDF) was performed to analyze the muscle activity. The findings of this study were 1) The backrest-point height of the auditorium chair and the height, length and width of the connected desk were shorter than what was suggested by the KS. Another difference was that the auditorium chair had a bigger angle of the backrest compared to the classroom chair. 2) Regarding within-subject effect the sole statistically significant difference was found between activation of the upper trapezius muscle. The upper trapezius muscle's %RVC in the APDF 10th-50th-90th percentile was statistically higher for participants sitting in the auditorium chair than for participants sitting in the classroom chair (p<.05). 3) There was an interaction effect between the 'two chair-types' and the 'two muscle-sides' in the APDF 10th-50th percentile (p<.05). 4) There was an interaction effect between the 'two chair-types' and the 'three gaze-direction' in the APDF 90th percentile (p<.05). The findings of this study indicated that maintaining a writing posture for a prolonged period of time in an auditorium chair significantly increased the left upper trapezius muscle activation compared to a classroom chair.

This study used an unstable platform to change the support surface type and position of both lower limbs in order to determine changes in weight distribution and muscle including the vastus medialis, tibialis anterior, lateral hamstring, and lateral gastrocnemius of both lower limbs were evaluated during knee joint flexing and extending in a semi-squat movement in 32 hemiplegic patients. The support surface conditions applied to the lower limbs were divided into four categories: condition 1 had a stable platform for both lower limbs; condition 2 had an unstable platform for the non-hemiplegic side and a stable platform for the hemiplegic side; condition 3 had a stable platform for the non-hemiplegic side and an unstable platform for the hemiplegic side; and condition 4 had an unstable platform for both sides. The normalized EMG activity levels of muscles and weight bearing ratio of both sides in the four surface conditions were compared using repeated measures ANOVA. A significant increase was found in the weight support distribution for the hemiplegic side in flexing and extending sessions in condition 2 compared to the other conditions (p<.05). A statistically significant decrease in significant decrease in asymmetrical weight bearing in flexing and extending sessions was observed for condition 2 compared to the other conditions (p<.05). A similar significant decrease was found in differences in muscular activity for both lower limbs in condition 2 (p<.05). The muscular activity of the hemiplegic side, based on the support surface for each muscle showed a significantly greater increase in condition 2 (p<.05). An unstable platform for the non-hemiplegic side and a stable platform for the hemiplegic side therefore increased symmetry in terms of the weight support distribution rate and muscle activity of lower limbs in hemiplegic patients. The problem of postural control due to asymmetry in hemiplegic patients should be further studied with the aim of developing continuous effects of functional training based on the type and position of the support surfaces and functional improvement.

Peripheral nerve injuries are very common in clinics and often result in severe functional deficits. The aim of this study was to evaluate the effect of treadmill running and electro-acupuncture on nerve regeneration and functional recovery of muscle activity following sciatic nerve crush injury in a rat model. A comparative study was conducted over 30 days on 60 adult male Sprague-Dawley rats grouped into sham control (C), electro-acupuncture (EA), treadmill (T), and treadmill plus electro-acupuncture (TEA). The left sciatic nerve was crushed for 30 sec using a hemostatic forceps and functional activity was evaluated with sciatic functional tests, nerve conduct velocity, muscle weight, and histology at 10, 20, and 30 days after injury. Muscle weight was significantly (P<0.05) increased between days 10 and 30 in the TEA group. In histology, the degree of damage was scored as C > TEA > T > EA, although necrosis and fibrosis of muscle was observed only in the TEA group. The EA and TEA groups showed rapid recovery with better myelinated axons on day 10. These results suggest that application of the TEA method with balanced exercise is a useful treatment option for peripheral nerve injury regeneration and muscle activity.

The aim of this study was to determine the immediate effects of single treatment of strain-counter strain (SCS) on pressure pain threshold (PPT) and muscle activity during scapular plane abduction with 3% body weight load. Fifteen asymptomatic male adults with upper trapezius latent trigger point (LTrP) (PPT<2.9 ) participated in this study. Pressure algometer was used to measure PPT and surface electromyography was used to record upper, middle arid lower trapezius, serratus anterior, infraspinatus and middle deltoid muscle activity and relative ratio during scapular plane abduction between pre- and post-intervention. There was a significant increase in upper trapezius PPT after a 90-second SCS (p<.05). The activity of the upper trapezius and middle deltoid was significantly decreased (p=.014, p=.001), coupled with a decreased muscle activity ratio between the upper and lower trapezius (p<.05). These results indicate that the SCS may effectively deactivate upper trapezius activity, thereby alleviating muscle balance and reducing pain sensitivity.

Foot posture is important in the development of the musculoskeletal structure in the lower limbs because it can change the mechanical alignment. Although foot orthotics are widely used for the correction of malalignments in the lower extremities, the biomechanical effects of wedges have not yet been cleared. The aim of this study was to investigate whether medial wedges affect the electromyographic (EMG) activity of the knee and hip joints in healthy adults that are performing one leg standing. Seventeen healthy volunteers performed the one leg standing under two foot conditions: A level surface, and a medial wedge. The subjects' EMG data for the gluteus maximus (Gmax), gluteus medius (Gmed), tensor fasciae latae (TFL), biceps femoris (BF), vastus lateralis (VL), and vastus medialis oblique (VMO) were recorded, along with the surface EMG, and all were analyzed. The EMG activity of the Gmed and TFL had significantly decreased under the medial wedge condition during one leg standing. Further study is needed in order to investigate whether medial wedges influence the EMG activity and kinematic data of the knee and hip joints as well as the ankle joints in adults with flexible flatfoot, while they are performing one leg standing.

The purpose of this study was to investigate the effects of meditation music with lumbar stabilization exercise on balance, concentration and muscle activation. Participants are divided into Group A and Group B. Group A listened to meditation music while doing 4 sets of lumbar stabilization exercise. Group B did not listen to meditation music while doing 4 sets of lumbar stabilization exercise. Surface EMG data was obtained rectus abdominis, external oblique, erector spinae, multifidus muscle during lumbar stabilization exercise. To examine the effect of before-after experiment for concentration and balance, paired t-test was adopted. Changes in EMG data of each muscles were analyzed by independence t-test. There were statistically significant increasing at concentration level and balance level in Group A. But significant difference was not shown in muscle activation. The clinical effect of the meditation music with lumbar stabilization exercise was investigated in this study with more excellent results in concentration and balance. In conclusion, these results suggest that meditation music and lumbar stabilization exercise may be useful in elderly people.

This study was to examine on the respiratory variables, heart rate and muscle activity between the static recovery and dynamic recovery after progressive resistance exercise to maximal point. Subjects were 15 students enrolled in N University. All were tested two times (static recovery and dynamic recovery) and were requested to perform a walking on a treadmill after progressive resistance exercise to maximal point. Electromyography(EMG) was used to monitor the muscle activity(TA: Tibialis Anterior, MG: Medial Gastrocnemius) during gait. CPEX-1 was used to measure the respiratory variables and heart rate. The dynamic recovery group was shown the significant lower heart rate than that of static recovery group at during gait. Respiratory rate showed statistically a significant difference. Electromyography(RMS, root mean square) showed a non-significant difference. But the dynamic recovery group of muscle activity was found highly in TA and MG. This study indicated that the dynamic recovery method evidenced more faster than the static recovery method. And this type of dynamic rest by walking can be a help of recovery after exercise.

The purpose of this study was to compare electromyography (EMG) activity for the middle and lower trapezius muscle according to various shoulder abduction angles. Thirty healthy male subjects were recruited for this study. Each subject performed three repetitions of horizontal abduction at 75˚, 90˚, 125˚, 160˚, and 180˚ of shoulder abduction angle in a prone position. Surface EMG activity was recorded from the middle and lower trapezius while the subjects held for five seconds at a predetermined position. The EMG activity was normalized using the maximal voluntary isometric contraction (MVIC) elicited using a manual muscle testing technique. A repeatedly measured ANOVA was performed by Bonferroni's post hoc test. The EMG activity of the middle and lower trapezius was significantly different among shoulder abduction angles (p<.05). The greatest level of muscle activity for the middle and lower trapezius were demonstrated at and of shoulder abduction angle, respectively. These results suggest that middle and lower trapezius strengthening exercise and manual muscle testing should be performed at different shoulder abduction angles.

The aim of this study was to determine the muscle activity of the abdominalis and erector spinae during bridging and unilateral bridging exercises on the firm surface, the sir-fit, and the foam roll. Eighteen healthy young subjects were recruited for this study. Surface electromyographic (EMG) activities were recorded from the both sides of the rectus abdominalis, external obliques, internal obliques, and erector spinae muscles during bridging and unilateral bridging-exercises. A one-way repeated analysis of variance was used to compare the EMG activity of each muscle according to the support surface condition. Differences in the EMG activities between the bridging and unilateral bridging exercises, and between the right and left side were assessed using a paired t-test. The study showed that the EMG activities of all of the muscles were significantly higher when the bridging exercise was performed using the foam roll or sit-fit than on the firm surface. The EMG activities of the right rectus abdominis, right external obliques, the right internal oblique, and both erector spinae were significantly higher during unilateral bridging ex exercise using the foam roll or the sit-fit than on the firm surface. The EMG activities of all of the muscles were significantly higher during the unilateral bridging exercise than during the bridging exercise. Based on these finding, performing the unilateral bridging exercise using the sit-fit or the foam roll is a useful method for facilitating trunk muscle strength and lumbar stability.

The aim of this study was to investigate the effects of lumbar stabilization on both trunk and lower limb muscle activity and center of pressure (COP) in single leg standing. Surface electromyography (EMG) was used to collect muscle activity data, the mean velocity of COP was measured using a force plate, and a pressure biofeedback unit was used for lumbar stabilization training. The findings of this study are summarized as follows: 1) The EMG activity of the erector spinae decreased significantly and the activity of the rectus abdominis, internal oblique, external oblique, gluteus maximus, and gluteus medius increased significantly with lumbar stabilization single leg standing. 2) No differences in activity in the tibialis anterior, medial gastrocnemius, rectus femoris, and medial hamstrings were found with single leg standing. 3) The mean velocity of COP in the antero-posterior and medio-lateral directions in the lumbar stabilization single leg standing decreased significantly compared with the preferred single leg standing. The findings of this study therefore indicate that lumbar stabilization can facilitate the co-activation of deep stabilization and global muscles that improve postural control capability during single leg standing.

This study was conducted to find the effects of scapular taping on muscle activities of the scapular rotators and upper trapezius pain in subjects with upper trapezius pain. Fifteen male subjects were recruited from Yonsei University for this study. Muscle activity of upper trapezius, lower trapezius, and serratus anterior was measured using surface electromyography. Visual analog scale was used for measuring upper trapezius pain. The subjects were asked to maintain shoulder flexion position with holding a 1 kg dumbbell in standing position. Scapular taping was applied over the muscle belly of the upper trapezius and attached parallel with the lower trapezius muscle fibers. For normalization, % maximal voluntary isometric contraction (%MVIC) was conducted. Paired t-test was applied to compare the muscle activities of scapular rotator and upper trapezius pain before and after applying the scapular taping. The muscle activity of the upper trapezius muscle and serratus anterior decreased significantly after tape application (p<.05). However, no significant difference was observed in lower trapezius muscle. The level of pain in the upper trapezius muscle significantly decreased after tape application (p<.05). The results of this study suggest that scapular taping can be used an additional therapy for reducing muscle activity of upper trapezius, serratus anterior and upper trapezius pain during shoulder flexion in patient with upper trapezius pain.

The purpose of this study was to compare EMG activity for pectoralis major muscle during shoulder movement with various abduction angle and rotation position in supine position. Fifteen healthy subjects were recruited for this study. All subjects performed shoulder horizontal adduction holding a 2 kg dumbbell in shoulder abduction 40˚, 70˚, 90˚, 130˚, 160˚ with shoulder neutral, internal rotation (IR), and external rotation (ER). Surface EMG activity was recorded from pectoralis major clavicle part and pectoralis major sternum part for 5 seconds and EMG activity was normalized to the value of maximal voluntary isometric contraction (%MVIC). Dependent variables were examined with 3 (Neutral, IR, ER) 5 (40˚, 70˚, 90˚, 130˚, 160˚) analysis of variance with repeated measures. The EMG activity of pectoralis major muscle was significantly different between shoulder abduction angles and between shoulder rotation positions (p<.05). The highest value of EMG activity of pectoralis major clavicle part among shoulder abduction angles was in 70˚ and, 90˚ in that order. The highest value of EMG activity of pectoralis major sternum part among shoulder abduction angles was in and 130˚, 90˚ in that order. According to the rotation degree, shoulder ER showed the highest value and IR showed the lowest value in both muscle parts. These results suggest that shoulder abduction 70˚, 90˚, 130˚ will be effective during manual muscle testing (MMT) and strengthening exercise for pectoralis major muscle. It is also supposed that shoulder ER is the efficient posture for strengthening of pectoralis major muscle.

This study compared the electromyographic activities and input performance of computer operators using a computer mouse and a trackball. Muscle activities were assessed at the upper trapezius (UT), middle deltoid (MD), extensor digitorum (ED), and first dorsal interosseous muscle (FDI). Twenty-six healthy subjects were recruited, and the test order was selected randomly for each subject. The task set was to click moving targets on a Windows program. The EMG amplitude was normalized using the percentage of reference voluntary contraction for UT and MD and the percentage of maximal voluntary contraction for ED and FDI. To analyze the differences in EMG activity, a paired t-test was used. UT muscle activities were significantly greater when the computer mouse was used (p<.05). FDI muscle activities were significantly greater when the trackball was used (p<.05). Using a trackball can reduce the load on the UT during computer work and help to prevent and manage work-related musculoskeletal disorders.

The purpose of this study was to suppose basis data the influence of different chair type and pelvic control on quadriceps muscle activity and strength during knee joint extension isometric exercise in hemiplegic patients. This research were investigated in ten healthy adults and tens hemipelgic patients. Surface electromyography (EMG) and Biodex system were used to collect kinematic data and muscle activity, respectively. Independent t-test, paired t-test and one-way repeated ANOVA were used to determine a statistical significance. The results showed as follows: (1) Posterior pelvic angles in healthy group and hemiplegic group were significantly different on isokinetic equipment (p<.05). (2) Different chair type and pelvic control on quadriceps muscle activity and strength were significantly different in hemiplegic patients (p<.05). From the result of this research, posterior pelvic angle control during knee joint extension isometric exercise in hemiplegic patients on isokinetic equipment is necessary to increase quadriceps muscle strength in hemiplegic patients.