Background: Inspiratory muscle training can improve inspiratory strength and endurance through threshold loading. In addition, trunk stabilization exercises can improve trunk strength and respiratory function. Objectives: The purpose of this study is to investigate the effect of application of inspiratory muscle training and trunk stabilization exercise on pulmonary function and inspiratory muscle activation in college students. Design: Randomized controlled trials. Methods: In this study, 24 college students were randomly divided into two groups: inspiratory muscle training and trunk stabilization exercise (experimental group, n=12), and trunk stabilization exercise (control group, n=12). Inspiratory muscle activity was measured using a surface electromyography. Pulmonary function was measured using a spirometer and a peak expiratory flow meter. Results: In the experimental group, the muscle activity of both upper trapezius and latissimus dorsi muscles increased significantly after the intervention. In the experimental group, both upper trapezius muscle activity was significantly increased than in the control group. In the experimental group, all the pulmonary function significantly increased after the intervention. Conclusion: In this study, when the inspiratory muscle training was additionally applied to the trunk stabilization exercise in college students in their twenty, it was possible to improve the inspiratory muscle activity and pulmonary function.

Background: Stroke patients have weak trunk muscle strength due to brain injury, so a single type of exercise is advised for restoring functionality. However, even after intervention, the problem still lies and it is suggested that another intervention method should be applied with exercise in order to deal with such problem. Objectives: To Investigate the effect of bridge exercise combined with functional electrical stimulation (FES) on trunk muscle activity and balance in stroke patients. Design: Randomized controlled trial. Methods: From July to August 2020, twenty stroke patients was sampled, ten patients who mediated bridge exercises combined with functional electrical stimulation were assigned to experiment group I, and ten patients who mediated general bridge exercises were assigned to experiment groupⅡ. For the pre-test, using surface EMG were measured paralyzed rectus abdominis, erector spinae, transverse abdominis/internal oblique muscle activity, and using trunk impairment scale were measured balance. In order to find out immediate effect after intervention, post-test was measured immediately same way pre-test. Results: Change in balance didn’t show significant difference within and between groups, but muscle activity of trunk was significant difference rectus abdominis and erector spinae within groups I (P<.01), also between groups was significant difference (P<.05). Conclusion: Bridge exercise combined with FES could improve trunk function more effectively than general bridge exercise due to physiological effect of functional electrical stimulation.

Background: Patients with low back pain (LBP) experience misalignments in the center of pressure (COP) and muscle imbalances due to frequent onesided posture adjustments to avoid pain. Objectives: To identify the effects of Squat Exercises with Vertical Whole-Body Vibration on the Center of Pressure and Trunk Muscle Activity. Design: Randomized controlled trial. Methods: Thirty LBP patients with an imbalance in the COP were sampled and randomly assigned to an experimental group of 15 patients who under went an intervention involving squat exercises with vertical WBV and a control group of 15 patients who were treated via a walking intervention. As pretests before the interventions, the subjects’ COP was identified by measuring their stability index (ST), and erector spinae, rectus abdominis, transverse abdominis, gluteus medius muscle activity was analyzed by determining the % reference voluntary contraction (%RVC) value using surface electromyography while sit to stand. After four weeks, a post test was conducted to remeasure the same variables using the same methods. Results: Statistically significant differences were found in the ST (P<.01) and trunk muscle (P<.05, P<.001) in the experimental group before and after the intervention. In terms of the differences between the left- and right-side (RL) muscle activity, only the transverse abdominis (TrA) and gluteus medius (GM) exhibited statistically significant increase (P<.05). A comparison of the groups showed statistically significant differences in the TrA with respect to muscle activity (P<.05) and in the RLTrA and RLGM in terms ofthe difference between left- and right-side muscle activity (P<.01). Conclusion: Squat exercises with vertical WBV produced effective changes in the COP of patients with LBP by reducing muscle imbalances through the delivery of a uniform force. In particular, strengthening the TrA and reducing an imbalance in the GM were determined to be important factors in improving the COP.

The aim of the present study was to investigate the effects of unilateral shoulder bag weight and heel heights on trunk muscle activities. This study recruited 40 healthy women in their twenties. Electromyography activities of rectus abdominis muscle, external abdominal oblique muscle, internal abdominal oblique muscle and erector spinae muscle during standing position were measured using a surface electromyography system. The overall muscle activities of the trunk muscles were significantly increased in the contralateral trunk muscles (p<.05). Inaddition, the trunk muscles overall activities on the contralateral side without the shoulder bag was positive correlation with the heel height and unilateral shoulder bag weight (p<.05). Both high-heeled wear and unilateral shoulder bags are fashion items that cause asymmetry in the trunk muscles of women in their twenties. These findings suggest that the increase in the weight and heel height of the unilateral shoulder bag in women cause asymmetry of trunk muscle activities.

The purpose of this study was to investigate the dynamic balance and activity of internal oblique muscle, multifidus muscle, gluteus maximus muscle, biceps femoris muscle during the Y balance test following the wearing of pelvic compression belt. Forty healthy adults were recruited for this test. The dynamic balance score was estimated as the following: (anterior+posteromdial+posterolateral)/(3×leg length)×100. The electromyography signals were measured through %reference voluntary contraction, which was normalized by reference voluntary contraction of Y balance test without wearing the pelvic compression belt. The paired t-test was carried out to compare the dynamic balance score and the activity of the trunk and hip extensor with and without the wearing of pelvic compression belt. The dynamic balance score of the Y balance test when wearing pelvic compression belt was significantly than when measured without wearing the pelvic compression belt (p<.05). The muscle activity of the internal oblique and the multifidus was significantly decreased when wearing pelvic compression belt (p<.05). The muscle activity of the gluteus maximus was significantly increased when wearing pelvic compression belt (p<.05). However, there was no significant difference in hamstring muscle activity, with or without wearing the belt (p>.05). In conclusion, this study shows that the wearing of pelvic compression belt affects trunk muscle and hip extensor muscle activity related to the pelvic mobility and stability and increases dynamic balance and also contributes to the stabilization of the external pelvic stabilization.

목적 : 본 연구는 뇌졸중으로 인한 편마비 환자들을 대상으로 앉은 자세에서 지지면의 안정성 변화가 상지기능 수준과 체간근육의 활성도에 미치는 영향을 알아보고자 하였다. 연구방법 : D광역시 ○○재활병원에 내원중인 편마비 환자 15명(남 9명, 여 6명)을 대상으로 앉은 자세에서 양발지지, 손상측지지와 비손상측지지를 사용하여 지지면의 안정성 변화를 중재하였다. 상지기능 수준은 Korea Employment Agency for the Disabled (KEPAD) 다차원 상지기능 작업표본검사로 측정하였고 체간근육의 활성도는 표면근전도를 사용하여 측정하였다. 결과 : 앉은 자세에서 세 가지 지지방법 간에 상지기능 수준을 비교한 결과 양발지지가 손상측지지에 비해 상지기능에 유의한 차이를 보였으나 비손상측으로 지면을 지지한 경우와 비교에서는 유의한 차이를 보이지 않았다. 체간근육의 활성도를 비교한 결과에서는 유의한 차이를 보이지 않았다. 결론 : 본 연구를 통해 임상에서 편마비 환자에게 앉은 자세로 작업수행을 할 경우 양발로 지면을 지지하는 것이 상지기능 수준에 긍정적인 영향을 미친다는 것을 알 수 있었다. 따라서 작업치료사는 환자에게 양발로 지면을 지지하도록하여 자세 안정성을 극대화시킨다면 기능적인 상지의 움직임을 촉진시킬 수 있을 것이다.

Most patients with chronic low back pain experience functional disability of trunk muscle, and limitations in physical activity. While there are many types of exercise programs available, in recent years sling exercise has been emerging as the exercise program for spinal stabilization. It has been supported by a great amount of research with positive findings on its effectiveness. This research studies the effects of bridging exercise, conducted on a sling, on pain level and trunk muscle activation in supine, sidelying, and prone positions during a 4 weeks period. 10 healthy people(normal group, n=10) and 28 patients with low back pain participated in this study. 28 patients were divided into two groups; one group participated in exercise with the sling(experimental group, n=14) and the other group exercised without the sling(control group, n=14). They were asked to use the Numerical Rating Scale(NRS) to answer to the level of their pain they felt (no pain: 0 point, severe pain: 10 points). During sling bridging exercises, the muscle activity level in each muscle measured in each position was standardized as three seconds of EMG signals during five seconds MVIC. In conclusion, the experimental group with four weeks of sling bridging exercise experienced a statistically significant reduction in the pain level(p<.05) and increase in the muscle activities of erector spinae when in supine position, internal oblique when in sidelying position, and rectus abdominis in prone position(p<.05). Regular sling bridging exercise reduces the low back pain and enhances other trunk muscle activation, thereby positively affect spinal stabilization.

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.

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.

An abdominal drawing-in maneuver (ADIM) with a pressure biofeedback unit can be used to prevent excessive lumbar lordosis during bridging exercise. Therefore, in this research, the effects of an ADIM on lumbar lordosis and lower extremity muscle activity during bridging exercise were investigated in thirty healthy adults. Surface electromyography (EMG) and VICON system were used to collect kinematic data and muscle activity, respectively. A paired t-test was used to determine a statistical significance. The results showed as follows: (1) When performing bridging exercise with an ADIM, the height of the anterior superior iliac spine and greater trochanter decreased significantly (p<.05). (2) When performing bridging exercise with an ADIM, the trunk extension angle and pelvic angle increased significantly (p<.05). (3) When performing bridging exercise with an ADIM, the EMG signal amplitude increased significantly in the rectus abdominis, internal oblique abdominis, external oblique abdominis, medial hamstring, and lateral hamstring (p<.05). (4) When performing bridging exercise with an ADIM, the EMG signal amplitude decreased significantly in the erector spinae (p<.05). From the result of this research, an ADIM trained with pressure biofeedback unit during bridging exercise is effective to prevent excessive contraction of erector spinae, to limit excessive motion of pelvis from sagittal plane and to increase muscle activity of abdominal muscles and hamstring muscle.

Cross-legged sitting postures are commonly assumed during computer work. The purpose of this study was to determine the effects of leg crossing on trunk muscle activity while typing at a computer. Trunk muscle activity was measured in three 8 different sitting postures, in random order. These posture were: normal sitting with a straight trunk and both feet on the floor (NS), upper leg crossing (ULC), and ankle on knee (AOK). The right leg was crossed onto the left leg in both cross-legged postures. Twenty able-bodied male volunteers participated in this study. Subjects typed on a computer keyboard for one minute. Surface electromyography (EMG) was used to record bilateral muscle activity in the external oblique (EO). internal oblique (IO), and rectus abdominis (RA). The EMG activity of each muscle in the NS posture was used as a reference (100% EMG activity) in relation to the two cross-legged postures. Muscle activity in the right EO. right IO, and left IO was significantly lower in the ULC posture than in the NS posture. In contrast, muscle activity in the right RA was significantly higher in the ULC posture than in the NS posture. Muscle activity in the tight RA was significantly higher in the AOK posture, as compared to the NS posture, whereas activity in the left IO was significantly lower in the AOK posture, as compared to the NS posture. The right-left muscle activity ratios in the EO and IO showed significantly different patterns in the cross-legged postures, suggesting that asymmetrical right-left oblique muscle activity had occurred.

Altered scapular kinematics in the scapular joint is commonly believed to be a factor contributing to trunk posture. The purpose of this study was to analyze the muscle activity with several changes of the shoulder angle. Tests were performed on 10 male subjects by repeated measures. Each subject was measured while sitting in both erect and slouched trunk positions. In each sitting posture, a three-dimensional motion analysis measurement was used to measure thoracic angle and shoulder abduction angle. Measurements were taken with the shoulder abdcution angle at , , , , , and . By using surface Electromyography (EMG) electrodes, we recorded the activity of the upper trapezius, middle trapezius, lower trapezius, middle deltoid, and serratus anterior muscle while the subject held a 4 kg weight at each angle. The mean of root mean square (RMS) of EMG activity was calculated. The middle trapezius, lower trapezius, and middle deltoid muscle activity showed significantly higher results but serratus anterior muscle activity showed significantly lower results (p<.05). With the shoulder angle increased, the muscle activity was also significantly increased (p<.05). In conclusion, the thoracic spine posture significantly affects the scapular muscle during scapular plane abduction, and the slouched posture is associated with increased trapezius muscle activity and with decreased serratus anterior muscle activity.