Characteristics of Trunk Muscles in Isokinetic Training at Different Velocities / 中国康复理论与实践

Objective:To study the presentation and changes of trunk flexors and extensors in isokinetic training at different velocities. Methods:From March to September, 2018, 27 health volunteers were enrolled. Their peak torques of trunk flexors and extensors at 30°/s, 60°/s, and 90°/s were collected. Results:The peak torques of trunk flexors and extensors slightly decreased with the increasing of velocities, but no significant difference was found (F < 2.070, P > 0.05). At 30°/s and 60°/s, the peak torque of extensors was higher than that of flexors (t > 3.138, P < 0.01); at 90°/s, no significant difference was found in the peak torque between flexors and extensors (t = -0.946, P > 0.05). The ratios of the peak torque of flexors to extensors were 0.79∶1 both at 30°/s and 60°/s. The peak torque of flexors decreased in the tenth contraction compared with the second contraction at all the angular velocities, however, it was significantly different only at 30°/s (t = 5.159, P < 0.01); meanwhile, the peak torque of extensors increased with significance only at 60°/s (t = -2.142, P < 0.05). Conclusion:At 30°/s and 60°/s, there might be a linear relation between trunk flexors and extensors, and the peak torque ratios of trunk flexors to extensors were approximately the same.

Effect of Forward and Backward Arm Extension Movement of Pilates Exercise Using Cadillac Instrument on Trunk Muscle Activity / 대한스포츠의학회지

PURPOSE: This study analyzed the muscle activity changes induced by motions of reaching forward and chest expansion that were examined from the bilateral muscles with rectus abdominis, external oblique, multifidus, and longissimus thoracic using Pilates cadillac instrument. METHODS: Nine young adult women, who have no musculoskeletal disorder and any of chronic diseases, were participated. Surface electromyography system was used for recording of all signals produced by muscles, and then normalized as percentage of maximum voluntary isometric contraction (%MVIC). The paired t-test and repeated measures of analysis of variance was performed. RESULTS: Reaching-forward motion showed a higher muscle activity from non-dominant external oblique muscle than that of the chest-expansion motion. During both reaching-forward motion and chest-expansion motion, MVIC values collected from dominant side of external oblique muscle were shown a significantly lower than the values obtained from non-dominant side (p < 0.05). Conversely, %MVIC values in external oblique muscle collected from dominant side showed a significantly higher than the values obtained from non-dominant side of the same oblique muscle (p < 0.05). Reaching-forward motion was caused a higher %MVIC on non-dominant external oblique muscle than that of the chest-expansion motion (p < 0.05). Regardless of dominant or non-dominant sides, external oblique muscle was shown the highest activation rate of all the other muscles during reaching forward action, and longissimus thoracic muscle was shown the highest activation rate of all the other muscles during chest expansion action. CONCLUSION: Reaching-forward motion is suitable for activating an external oblique muscle, and chest-expansion motion is an effective enough in activating of longissimus thoracic muscle.

Effects of NMES and Horseback Riding Using a Robotic Device on the Trunk Muscle Activity and Gross Motor Function in Children with Spastic Diplegia

PURPOSE: This study examined the effects of neuromuscular electrical stimulation (NMES) and horseback riding using a robotic device on the trunk muscle activity and gross motor function in children with spastic diplegia. METHODS: Children with spastic diplegia were divided into two groups: an experimental group (NMES and horseback riding using a robotic device [n=10]) and a control group (placebo NMES and horseback riding using a robotic device [n=10]). Each group received general physical therapy and occupational therapy. Each intervention involved the administration of NMES for 15 minutes and horseback riding using robotic device therapy for 15 minutes three times a week for 4 weeks. The evaluation included both the rectus abdominis muscles (RA), external oblique muscles (EO), thoracic paraspinal muscles (TP), and lumbar paraspinal muscles (LP) activity and GMFM. RESULTS: The RA, EO, TP, and LP muscle activity, GMFM C, D, and E were increased significantly in the experimental and control groups. A significant increase in both the TP muscle activity and GMFM D was observed in the experimental group compared to the control group. CONCLUSION: This study showed that horseback riding using a robotic device is an effective intervention for trunk muscle activity and GMFM in children with spastic diplegia. However, if NMES is added to the back muscles, it is possible to further increase the thoracic paraspinal muscle activity and standing ability.

Effects of Active Vibration Exercise on Trunk Muscle Activity, Balance, and Activities of Daily Living in Patients with Chronic Stroke

PURPOSE: This study aimed to investigate the effect of active vibration exercise on trunk muscle activity, balance, and activities of daily living in patients with chronic stroke. METHODS: Twenty-four patients with chronic stroke were randomly assigned to an experimental (n=12) or a control (n=12) group. The experimental group performed an active vibration exercise workout for 20 minutes a day five times a week for 4 weeks using a flexi-bar. Trunk muscle activity was measured using surface electromyography. Balance was measured using the Berg balance scale. Activities of daily living were measured using the functional independence measure. RESULTS: The intragroup comparison showed significant differences in the rectus abdominis, internal oblique, and external oblique muscle activity values, Berg balance scale score, and functional independence measurement values in the experimental group. The intergroup comparison showed that differences in the rectus abdominis and internal oblique external oblique muscle values, Berg balance scale score, and functional independence measurement value for the experimental group were significantly related to those in the control group. CONCLUSION: Based on these results, this study proved that the active vibration exercise effectively improved trunk muscle activity, balance, and activities of daily living in patients with chronic stroke.

Effects of Flexible Pole Training Combined with Lumbar Stabilization on Trunk Muscles Activation in Healthy Adults

OBJECTIVE: This study aimed to determine the efficacy of flexible pole training combined with lumbar stabilization in improving trunk muscle activities and to investigate the difference according to posture in young adults. METHODS: Twenty-five participants were enrolled in this study. The subjects were randomly allocated into either the flexible pole group or the rigid pole group. Participants performed lumbar stabilization exercises on quadruped and curl-up, with the flexible pole or rigid pole. Electromyography was used to assess the percent maximal voluntary isometric contracion (%MVIC) of the rectus abdominis (RA), external oblique (EO), internal oblique (IO), and erector spine (ES) muscles. All participants completed one 30-minute session per day, 3 days per week, for 6 weeks. The evaluation was performed before and 6 weeks after the training, and follow-up. The data were analyzed using independent t-test and two-way repeated measure analysis of variance to determine the statistical significance. RESULTS: The flexible pole in curl-up showed significant differences in EO and IO muscle activities compared with the rigid pole. The flexible pole in quadruped showed significant differences in IO and ES muscle activities compared with the rigid pole. The RA, EO, IO, and ES muscle activities of both groups were significantly higher after 6 weeks training. CONCLUSION: The flexible pole in curl-up and quadruped showed an improvement in trunk muscle activation. The flexible pole combined with lumbar stabilization will be useful as an exercise tool to improve activity of trunk muscles.

Do Trunk Muscles Affect the Lumbar Interbody Fusion Rate?: Correlation of Trunk Muscle Cross Sectional Area and Fusion Rates after Posterior Lumbar Interbody Fusion Using Stand-Alone Cage

OBJECTIVE: Although trunk muscles in the lumbar spine preserve spinal stability and motility, little is known about the relationship between trunk muscles and spinal fusion rate. The aim of the present study is to evaluate the correlation between trunk muscles cross sectional area (MCSA) and fusion rate after posterior lumbar interbody fusion (PLIF) using stand-alone cages. METHODS: A total of 89 adult patients with degenerative lumbar disease who were performed PLIF using stand-alone cages at L4-5 were included in this study. The cross-sectional area of the psoas major (PS), erector spinae (ES), and multifidus (MF) muscles were quantitatively evaluated by preoperative lumbar magnetic resonance imaging at the L3-4, L4-5, and L5-S1 segments, and bone union was evaluated by dynamic lumbar X-rays. RESULTS: Of the 89 patients, 68 had bone union and 21 did not. The MCSAs at all segments in both groups were significantly different (p<0.05) for the PS muscle, those at L3-4 and L4-5 segments between groups were significantly different (p=0.048, 0.021) for the ES and MF muscles. In the multivariate analysis, differences in the PS MCSA at the L4-5 and L5-S1 segments remained significant (p=0.048, 0.043 and odds ratio=1.098, 1.169). In comparison analysis between male and female patients, most MCSAs of male patients were larger than female's. Fusion rates of male patients (80.7%) were higher than female's (68.8%), too. CONCLUSION: For PLIF surgery, PS muscle function appears to be an important factor for bone union and preventing back muscle injury is essential for better fusion rate.

The Effect of Visual Information Provision on the Changes of Electromyogram Activity in Trunk and Lower Leg Muscles during Dynamic Balance Control / 대한스포츠의학회지

The purpose of this study was to investigate the changes of electromyogram activity of trunk and lower leg muscles during dynamic balance control in 20 healthy adult subjects when various experimental visual conditions were applied. Surface electromyography system was used for recording of any signals produced by muscles. Muscle activity was recorded from muscles, of which left and right sides of rectus abdominis, external obliques, longissimus thoracis, multifidus, vastus medialis, biceps femoris, gastrocnemius medialis, and tibialis anterior, and then normalized as percentage of maximum voluntary isometric contraction. All data obtained from experiment were analyzed using SPSS ver. 20.0, and two-way analysis of variance were used to determine statistical significance between two factors (3x2 factorial analysis, visual conditions vs. leg conditions). Statistical significance levels were set at alpha=0.05. There were significant different in biceps femoris and external obliques muscle's activities between right and left leg, showing more prominent reduction in left leg when blind vision condition was given. Significantly higher muscle activities were shown in both sides of multifidus (p<0.05), vastus medialis (p<0.001), tibialis anterior (p<0.001) and gastrocnemius medialis (p<0.001) with sighted vision and blanking vision compared to the condition of blind vision. These results confirmed that muscle activity is prominently stimulated by visual information provision, and this implies that visual input may be a major factor for maintaining of the body's balance control.

Patterns for EMG activity of trunk muscles during front and back lifting and lowering with two hands / 医用生物力学

Objective To observe electromyography (EMG) activity and kinematic characteristics of the dorsal and ventral muscles during extension-flexion of the trunk． Methods Ten healthy male subjects stood on a test platform, performing the front and back lifting and lowering. The EMG activity of 10 muscles (rectus abdominus, external oblique, gluteus medius, erector spinae, multifidus), the angular movement, the plantar center of pressure (COP) were recorded at the same time. The average amplitude of EMG, contribution ratio of muscles, and COP displacement were calculated, and statistical analyses of all the data were conducted． Results During front lifting and lowering, the activity of dorsal muscles was greater than that of ventral muscles under both loading and unloading, and the contribution ratio of dorsal muscles was increasing with loading. During back lifting and lowering, the activity of ventral muscles was slightly greater, but the contribution ratio of both dorsal and ventral muscles was very close. The contribution ratio of ventral muscles was increasing with loading, while the activity of dorsal muscles decreased. The activity of gluteus medius was increasing with loading, but the contribution ratio was basically consistent under both loading and unloading. Conclusions During extension-flexion of the trunk, muscle activation varies with the load size and trunk position. Under loading at front, dorsal muscles are working as an agonist, while ventral muscles as antagonist; under loading at back, ventral muscles become an agonist and dorsal muscles as a co-activator. The activity of gluteus medius might play a role of stabilization during front and back lifting and lowering.

Efficacy of Rehabilitation for Patients with HAM (HTLV-1 associated myelopathy) / The Japanese Journal of Rehabilitation Medicine

The effectiveness of rehabilitation in patients with HTLV-1associated myelopathy (HAM) was evaluated. The HAM patient is characterized by chronic progressive spastic paraplegia with dysuria and muscular weakness of the lower trunk, as well as the pelvic and hip muscles. However, the muscular strength of the lower limbs and feet is relatively well maintained. The 12 subjects enrolled in this study included 2 men and 10 women. Their average age was 53.2 years, their average duration of disease was 20.5 years, and they were involved in training for an average of 41 days. The rehabilitation program involved muscular strength training of the lower trunk, pelvic, and hip muscles. After all patients completed the rehabilitation program, a significant improvement was seen in the truncal flexors, the truncal extensors, and the truncal rotators in the lower trunk. As for the hip muscles, a significant improvement was seen in the iliopsoas, the gluteus maximus, and the gluteus medius. The improvement was evaluated using Osame's Motor Disability Score (OMDS), the Functional Independence Measure (FIM) and the Barthel Index. The patients' improvements in motor function and ADL suggest that rehabilitation was effective.

The Effects of Isokinetic Strengthening of Trunk Muscles on Balance in Hemiplegic Patients

OBJECTIVE: To identify the effects of isokinetic strengthening of trunk muscles on balance in hemiplegic patients after stroke. METHOD: All participants were ambulatory hemiplegic patients, injured at least 6 months prior to study. The patients (n=16) were randomly divided into two groups. The control group received neurodevelopmental treatments and gait training 3 times a week. In addition to the same treatments provided for the control group, the experimental group received trunk isokinetic strengthening exercises using isokinetic dynamometer 3 times a week. Trunk muscle peak torque and balance in the experimental group were compared with those in control group at baseline and 4 weeks after treatments. RESULTS: There were no significant differences in age, lesion of hemiplegia, time after stroke onset, trunk muscle strength and Berg balance score before treatments between two groups. In the experimental group, peak torques of trunk extensor increased significantly at 60degrees/sec and 90degrees/sec at 4 weeks (p<0.05), but there were no significant improvements in peak torques of trunk flexor at all degree and extensor peak torques at 120degrees/sec. Both the extensor and flexors showed no significant changes in the control groups. In the experimental group, a mean percent change in peak torque involving the trunk extensor was significantly increased at 60degrees/sec. In the experimental group, Berg balance scores, 10 m gait velocity, sit to stand and gait 3 m and return, and 10 seconds stair up and down were improved (p<0.05). No significant improvements were noted in the control group. CONCLUSION: Isokinetic strengthening of trunk muscles can improve balance in hemiplegic patients.

CHANGES IN INTRA-ABDOMINAL PRESSURE AND TRUNK ACTIVATION DURING DROP JUMP / 体力科学

This study examined changes in intra-abdominal pressure and trunk activation during drop jump and the influence of those factors on performance. Intra-abdominal pressure (IAP) and surface electromyography (EMG) activity from the rectus abdominis (RA), transversus abdominis-internal oblique (TrA-IO) and erector spinae (ES) muscles were measured in seven males (22.3±1.0 years) during double-leg drop jumps from a 0.4 m height. Development of IAP (ΔIAP) and normalized rmsEMGs were calculated in the pre-contact, impact and push-off phases, after divided by ground reaction force data. TrA-IO activation which occurred prior to ground contact were the earliest and strongest compared to other muscles activation during each phase.ΔIAP during the impact phase coincided with the peak vertical force. There were significant positive correlations between ΔIAP, TrA-IO activation and vertical force per weight. In addition, the contact time correlated negatively with ΔIAP, TrA-IO activation and vertical force per weight. These findings indicate that ΔIAP and TrA-IO activation may contribute to trunk stability and efficient landing during double-leg drop jump.

THE CIRCULATION RESPONSE DURING CONTIONUOUS ISOMETRIC CONTRACTION ON TURNK MUSCLE / 体力科学

The purpose of this study was to investigate the circulation responses (heart rate (HR), systolic blood pressure (SBP) and second derivative of photoplethysmogram waveform index (|d/a|)) during 90 seconds continuous isometric contraction on trunk muscle. Subjects were 10 healthy male (22±1 years). Subjects performed 90 seconds continuous isometric contraction on Rectus Abdominus. Contraction intensity was 55.4±13.8% maximal voluntary contraction.HR and SBP were a significant increase after contraction beginning, immediately. |d/a| (one of the peripheral blood vessel contraction index) was a significant increase at 60 seconds after contraction beginning. After that, HR was an increase more, |d/a| showed a decline tendency. But, SBP was an increase more.The followings are suggestive by these results. When the contraction beginning, HR was increased immediately by central command, muscle mechano reflex and so on. The other hand, the peripheral blood vessel contraction was late by the accumulation of metabolism product from active muscle was late. When the prolong contraction time, the peripheral blood vessel was extension. But, SBP was increased more by increasing the cardio output, muscle tension and so on.

A study on correlation between the isometric and isokinetic concentric muscle strength of trunk flexors and extensors / 中华物理医学与康复杂志

Objective To explore the correlation between the strength of trunk flexors and extensors obtained by isometric and isokinetic concentric tests. Methods The strength of trunk extensors and flexors were measured by isometric and isokinetic concentric tests during trunk flexion and extension in 50 healthy subjects, and the peak torque of flexion and extension (FPT and EPT) and the ratios of FPT/EPT were analyzed with correlation and regression analysis. Results The FPT and EPT of trunk flexors and extensors were positively correlated (r_F=0.827,P0.05, respectively), the regression equations of FPT and EPT were y

The effect of intensive trunk muscle training on balance and walking in hemiplegic patients / 中华物理医学与康复杂志

Objective To study the effect of intensive trunk muscle training on balance and walking in pa- tients with hemiplegia caused by stroke.Methods A total of 90 stroke patients were recruited and randomly divid- ed into a treatment group(45 cases)and a control group(45 cases).All the patients were given conventional reha- bilitation training.Meanwhile,intensive trunk muscle training was also administered for those in the treatment group as well.The trunk control function,balance ability and walking ability were assessed by using the trunk control test, Berg Balance Scale and the balance subscale of the Fugl-Meyer physical performance test,and Holden's functional ambulation classification,respectively,before and after 6 weeks of training.Results It was found that all the pa- tients scored better with the trunk control test,Berg's balance scale,the balance subscale of the Fugl-Meyer physical performance test and Holden's ambulation classification after treatment,and there were significant differences between the two groups after treatment(P

Physical characteristics of university wrestlers with low back pain / 体力科学

The purpose of this study was to investigate the relationship between low back pain (LBP) any physical characteristics in university wrestlers. We especially focused on radiological abnormalitie (RA) in their lumbar regions.<BR>Physical characteristics and isokinetic trunk muscle strength of the 55 male university wrestlers were measured. MRI was used to evaluate the cross-sectional areas of trunk muscles between lumbar spine 3 and 4 (L3/4) . Evaluations of LBP were based on the diagnose of orthopedic surgeons and the questionnaire test. According to this evaluation, we assigned all wrestlers into two groups as the LOP group and the no LOP group. Furthermore, four groups were defined by having RA based on X-ray and MRI diagnose.<BR>We obtained the following results. In comparison between the LOP group and the no LOP group, the trunk muscle extension flexion strength ratio of the LOP was significantly lower than that of the no LOP group. In addition, the LOP without RA group showed significant low strength of their trunk extensors in comparison with the no LOP without RA group.<BR>We considered that the relative low strength of trunk extensors should have some effect on LBP in university wrestlers.

BIOMECHANICAL STUDY OF TRUNK MUSCLE STRENGTH AND INTERRELATED STUDY IN PATIENTS WITH LOW BACK PAIN CAUSED BY MILITARY TRAINING / 解放军医学杂志

To ascertain the change of trunk muscle strength and lumbar curvature and cross sectional area of M. sacrospinalis in low back pain caused by military training, the indexes of trunk muscle strength (PT/BW, TAE, F/E) were measured in patients with low back pain and healthy subjects with CYBEX 6000 isokinetic testing system. The lumbar curvature was measured in lumbar X ray films on the lateral projection in standing position, and the cross sectional area of sacrospinalis was measured by ultrasonography. All of the indexes were compared between the two groups.The results showed PT/BW of flexors was not significantly different between the patients and healthy subjects, TAE of flexors in patients was lower than that of healthy subjects ( P

The Effect of Chronic Low Back Pain on Bone Mineral Density and Trunk Muscle Strength in Women

OBJECTIVE: To evaluate (1) the effect of chronic low back pain on bone mineral density, and (2) the effect of chronic low back pain on trunk muscle strength in women. METHOD: Subjects were 118 women patients (ages of 28~65 years) suffering from chronic low back pain more than three months and control groups were 218 healthy women (age of 26~72 years). We measured bone mineral density (BMD) at the lumbar spine and proximal femur using Dual X-ray absorptiometry and trunk muscle strength using Cybex 660 dynamometer. RESULTS: There was no significant difference between groups in lumbar spine BMD, in proximal femur BMD, or in trunk flexor muscle strength. However, trunk extensor muscle strength was reduced significantly in patient group. Trunk extensor muscle peak torque was 64.69+/-18.48 Nm in the patient group and 73.84+/-22.50 Nm in the control group in 30 degrees/sec, and 58.65+/-18.59 Nm in the patient group and 65.68+/-20.28 Nm in the control group in 60 degrees/sec. CONCLUSION: The results suggest that chronic low back pain does not affect the BMD. However, it causes trunk extensor muscle weakness; therefore, trunk extension exercise will be help to the patients with chronic low back pain.

Trunk Muscle Strength and Bone Mineral Density in Women

OBJECTIVE: The purpose of this study was to investigate a correlation between the muscle strength of trunk and bone mineral density (BMD) in women. METHOD: A total of 218 healthy women participated in the study. Their age ranged from 26 to 72 years. Dual X-ray absorptiometry was used to measure the BMD of lumbar spine and the trunk muscle strength was assessed by a Cybex NORMTM system. Under the standard criteria of World Health Organization for the dual X-ray absorptiometry analysis, we divided spine T-score into three groups(group 1: osteoporosis, group 2: osteopenia, and group 3: normal). RESULTS: The data revealed a siginificant correlation (r= 0.455, p=0.0001) between the age and BMD of lumbar spine. Trunk extensor muscle strength revealed 56.27+/-18.08 Nm (mean+/-SD) in osteoporosis group, 72.84+/-21.69 Nm in osteopenic group, and 77.90+/-22.28 Nm in normal group. Trunk flexor muscle strength was 82.73+/-23.30 Nm in osteoporosis group, 86.00+/-19.77 Nm in osteopenic group, and 98.91+/-18.29 Nm in normal group. CONCLUSION: These results indicated that the trunk extensor muscle was weaker than the flexor muscle in osteoporotic group. As the bone mineral density reduced, the strength of both trunk extensor and flexor decreased. However the weakness of trunk flexor occurred at the earlier stage of osteoporosis than the weakness of trunk extensor.

MORPHOLOGICAL CHARACTERISTICS OF TRUNK MUSCLE GROUPS IN JAPANESE FEMALE ELITE JUDO ATHLETES / 体力科学

Using three-dimensional (3 D) imaging, we investigated the morphological characteristics of the M, latissiums dorsi (LD) and M, erector spinae (ES) of the dorsal trunk in judo athletes employing a computer graphics system on magnetic resonance imaging (MRI) . The subjects were five healthy untrained women (HUW) without lower back pain syndrome, and five Japanese female elite judo athletes (EJA) . There was no significant difference in height or weight between the HUW and EJA. Three-dimensional imaging of the LD and ES was reconstructed visually, based on MRI consecutive slice data taken from the first thoracic vertebra to the symphysis pubis along the trunk. Then the volume of the LD and ES was determined using a surface reconstruction algorithm.<BR>The morphological characteristics of the LD in the EJA appeared to indicate enlargment compared with those in the HUW, whereas the characteristics of the ES in both groups were similar. The volume of the LD was significantly different between the HUW (226.6±33.18 m<I>l</I>) and EJA (438.1±107.8 m<I>l</I>), whereas that of the ES showed no difference (HUW; 257.4±78.8 m<I>l</I>, EJA ; 284.0±74.82 m<I>l</I>) . In the EJA, but not in the HUW, there was a significant positive correlation between the volume of the LD and weight, and differences were noted between the two regression slopes. There was also a positive correlation between the volume of the ES and weight in both the HUW and EJA, which showed the same simple linear regression slope. These results suggest that the muscle hypertrophy evident in the LD, but not in the ES, is related to the effects of Judo training.

The change in trunk muscle performance in recruits with low back pain caused by military training and its prevention / 解放军医学杂志

To elucidate the change in trunk muscle performance in patients with low back pain caused by military training. The indices of trunk muscle strength (PT/BW, TAE, F/E, ER), the cross-sectional area of sacrospinalis, the amplitude and the duration of EMG, and the lumbar curvature were measured in recruits with low back pain after military training (n=40)and healthy subjects(n=40).All of the indices were compared between two groups. It was found that except PT/BW and ER of flexors and cross-sectional area of sacrospinalis, there were significant differences between other indices of the patients compared with healthy subjects(P