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Spine Mar 2006An operator blinded dual modality trial of measurement of the abdominal muscles during "drawing-in" of the abdominal wall. (Comparative Study)
Comparative Study
STUDY DESIGN
An operator blinded dual modality trial of measurement of the abdominal muscles during "drawing-in" of the abdominal wall.
OBJECTIVES
1) To investigate, using magnetic resonance imaging (MRI), the function of the transversus abdominis muscle bilaterally during a drawing-in of the abdominal wall. 2) To validate the use of real-time ultrasound imaging as a measure of the deep abdominal muscle during a drawing-in of the abdominal wall.
SUMMARY OF BACKGROUND DATA
Previous research has implicated the deep abdominal muscle, transversus abdominis, in the support and protection of the spine and provided evidence that training this muscle is important in the rehabilitation of low back pain. One of the most important actions of the transversus abdominis is to "draw-in" the abdominal wall, and this action has been shown to stiffen the sacroiliac joints. It is hypothesized that in response to a draw in, the transversus abdominis muscle forms a deep musculofascial "corset" and that MRI could be used to view this corset and verify its mechanism of action on the lumbopelvic region.
METHODS
Thirteen healthy asymptomatic male elite cricket players aged 21.3 +/- 2.1 years were imaged using MRI and ultrasound imaging as they drew in their abdominal walls. Measurements of the thickness of the transversus abdominis and internal oblique muscles and the slide of the anterior abdominal fascia were measured using both MRI and ultrasound. Measurement of the whole abdominal cross-sectional area (CSA) was conducted using MRI.
RESULTS
Results of the MRI demonstrated that, as a result of draw-in, there was a significant increase in thickness of the transversus abdominis (P < 0.001) and the internal oblique muscles (P < 0.001). There was a significant decrease in the CSA of the trunk (P < 0.001). The mean slide (+/-SD) of the anterior abdominal fascia was 1.54 +/- 0.38 cm for the left side and 1.48 +/- 0.35 cm for the right side. Ultrasound measurements of muscle thickness of both transversus abdominis and the internal oblique, as well as fascial slide, correlated with measures obtained using MRI (interclass correlations from 0.78 to 0.95).
CONCLUSIONS
The MRI results demonstrated that during a drawing-in action, the transversus abdominis contracts bilaterally to form a musculofascial band that appears to tighten (like a corset) and most likely improves the stabilization of the lumbopelvic region. Real-time ultrasound imaging can also be used to measure changes in the transversus abdominis during the draw-in maneuver.
Topics: Abdominal Muscles; Abdominal Wall; Adult; Humans; Low Back Pain; Magnetic Resonance Imaging; Male; Muscle Contraction
PubMed: 16540858
DOI: 10.1097/01.brs.0000202740.86338.df -
Spine Jan 1998A biomechanical model of the lumbar spine was used to calculate the effects of abdominal muscle coactivation on spinal stability.
STUDY DESIGN
A biomechanical model of the lumbar spine was used to calculate the effects of abdominal muscle coactivation on spinal stability.
OBJECTIVES
To estimate the effects of abdominal muscle coactivation on lumbar spine stability, muscle fatigue rate, and lumbar spine compression forces.
SUMMARY OF BACKGROUND DATA
The activation of human trunk muscles has been found to involve coactivation of antagonistic muscles, which has not been adequately predicted by biomechanical models. Antagonistic activation of abdominal muscles might produce flexion moments resulting from abdominal pressurization. Qualitatively, antagonistic activity also has been attributed to the need to stabilize the spine.
METHODS
Spinal loads and spinal stability were calculated for maximum and submaximum (40%, 60% and 80%) efforts in extension and lateral bending using a previously published, anatomically realistic biomechanical model of the lumbar spine and its musculature. Three different antagonistic abdominal muscle coactivation patterns were imposed, and results were compared with those found in a model with no imposed coactivation.
RESULTS
Results were quantified in terms of the sum of cubed muscle stresses (sigma sigma m3, which is related to the muscle fatigue rate), the maximum compressive loading on the lumbar spine, and the critical value of the muscle stiffness parameter (q) required for the spine to be stable. Forcing antagonistic coactivation increased stability, but at the cost of an increase in sigma sigma m3 and a small increase in maximum spinal compression.
CONCLUSIONS
These analyses provide estimates of the effects of antagonistic abdominal muscle coactivation, indicating that its probable role is to stabilize the spine.
Topics: Abdominal Muscles; Compressive Strength; Humans; Lumbar Vertebrae; Stress, Mechanical; Weight-Bearing
PubMed: 9460158
DOI: 10.1097/00007632-199801010-00019 -
Journal of Bodywork and Movement... Jan 2020Expiratory flow is important to minimize the risk of infection by expelling foreign substances from the lungs. Abdominal muscle activities primarily produce expiratory...
INTRODUCTION
Expiratory flow is important to minimize the risk of infection by expelling foreign substances from the lungs. Abdominal muscle activities primarily produce expiratory flow. However, data on the association of abdominal muscle activity during expiratory effort and abdominal exercise posture with expiratory flow rate is limited. This study aimed to assess the correlation between expiratory flow and abdominal muscle activity while holding maximum expiration and performing the side bridge exercise in elderly women.
METHODS
Rectus abdominis (RA), external oblique (EO), and internal oblique (IO) muscle activity was measured using electromyography in 14 elderly women (82.8 ± 6.7 years), who could walk independently while performing 2 tasks: holding their breath after maximum expiration in the crook-lying position (maximum expiration), and performing the side bridge exercise on their knees without breathing instruction (side bridge). Peak expiratory flow (PEF) was obtained using a peak flow meter. Correlations between PEF and the abdominal muscle activity were determined using the Spearman rank correlation coefficient.
RESULTS
The correlation coefficients between PEF and RA, EO, and IO activity while holding maximum expiration were 0.407 (p = 0.149), -0.345 (p = 0.227), and 0.732 (p = 0.003), respectively. The correlation coefficients between PEF and RA, EO, and IO activity while performing the side bridge exercise were -0.297 (p = 0.303), -0.552 (p = 0.041), and 0.147 (p = 0.615), respectively.
CONCLUSIONS
Higher IO activity while holding maximum expiration or lower EO activity while performing the side bridge exercise was related to higher PEF. Thus, maximum expiration and abdominal exercise might be effective in the improvement or prevention of the decrease of expiratory flow.
Topics: Abdominal Muscles; Aged; Aged, 80 and over; Electromyography; Exercise; Exhalation; Female; Forced Expiratory Flow Rates; Humans; Physical Therapy Modalities; Posture
PubMed: 31987551
DOI: 10.1016/j.jbmt.2019.05.026 -
European Journal of Applied Physiology... 1993The purpose of this study was to determine and compare interactions between the abdominal musculature and intra-abdominal pressure (IAP) during controlled dynamic and...
The purpose of this study was to determine and compare interactions between the abdominal musculature and intra-abdominal pressure (IAP) during controlled dynamic and static trunk muscle loading. Myoelectric activity was recorded in six subjects from the rectus abdominis, obliquus externus, obliquus internus, transversus abdominis and erector spinae muscles using surface and intra-muscular fine-wire electrodes. The IAP was recorded intra-gastrically. Trunk flexions and extensions were performed lying on one side on a swivel table. An adjustable brake provided different friction loading conditions, while adding weights to an unbraked swivel table afforded various levels of inertial loading. During trunk extensions at all friction loads, IAP was elevated (1.8-7.2 kPa) with concomitant activity in transversus abdominis and obliquus internus muscles--little or no activity was seen from rectus abdominis and obliquus externus muscles. For inertia loading during trunk extension, IAP levels were somewhat lower (1.8-5.6 kPa) and displayed a second peak when abdominal muscle activity occurred in the course of decelerating the movement. For single trunk flexions with friction loading, IAP was higher than that seen in extension conditions and increased with added resistance. For inertial loading during trunk flexion, IAP showed two peaks, the larger first peak matched peak forward acceleration and general abdominal muscle activation, while the second corresponded to peak deceleration and was accompanied by activity in transversus abdominis and erector spinae muscles. It was apparent that different loading strategies produced markedly different patterns of response in both trunk musculature and intra-abdominal pressure.
Topics: Abdomen; Abdominal Muscles; Adolescent; Adult; Electromyography; Humans; Isometric Contraction; Male; Muscle Contraction; Stress, Mechanical
PubMed: 8495692
DOI: 10.1007/BF00237775 -
Journal of Strength and Conditioning... Aug 2003The purpose of this study was to compare the abdominal muscle activity elicited while using 4 portable abdominal training devices vs. a traditional crunch. Thirty-three... (Comparative Study)
Comparative Study
The purpose of this study was to compare the abdominal muscle activity elicited while using 4 portable abdominal training devices vs. a traditional crunch. Thirty-three adults participated in this study. The exercise devices tested included the Ab Roller Plus, Torso Track 2, AB-DOer Pro, and the Perfect Abs. All subjects were tested on the Perfect Abs in both a seated and supine position using low-, medium-, and high-resistance bands. The Torso Track 2 was also tested at low- and high-resistance settings. Surface electromyography (EMG) was recorded from the upper and lower portions of the rectus abdominis, external oblique, and the rectus femoris during each repetition. Statistical analyses were performed on the mean EMG values using a repeated analysis of variance (ANOVA) procedure. There was no significant difference in abdominal muscle activity between the Ab Roller Plus, the Torso Track 2 (high resistance), and a traditional crunch. The mean abdominal muscle activity was significantly lower than a normal crunch, however, when using the AB-DOer, Torso Track (low resistance), and the Perfect Abs seated with the low-resistance band. In contrast, the Perfect Abs, when used in the supine position with the medium- and high-resistance bands, elicited significantly greater mean abdominal muscle activity than a crunch. Of the 4 devices tested, only the Perfect Abs when used in the supine position with the medium- and high-resistance bands, elicited more abdominal activity than a crunch. The results suggest that portable abdominal devices are most effective if they not only mimic the mechanics of a traditional crunch, but also provide external resistance to increase the involvement of the abdominal musculature.
Topics: Abdominal Muscles; Adult; Analysis of Variance; Biomechanical Phenomena; Electromyography; Exercise; Female; Humans; Male; Muscle Contraction
PubMed: 12930170
DOI: 10.1519/1533-4287(2003)017<0463:eaoama>2.0.co;2 -
Journal of Back and Musculoskeletal... 2018Lateral abdominal muscles control the lumbar region and this manages the stability of the trunk through co-contraction. Abdominal drawing-in maneuver (ADIM) is the basis...
BACKGROUND
Lateral abdominal muscles control the lumbar region and this manages the stability of the trunk through co-contraction. Abdominal drawing-in maneuver (ADIM) is the basis method for spine stabilization to restore proper neuromuscular control.
OBJECTIVE
To investigate the effect of therapeutic abdominal drawing-in maneuver on abdominal muscle thickness and balance.
METHODS
Twenty healthy adults were divided into 2 groups. The experimental group performed a bridging exercise with ADIM whereas the control group performed a bridging exercise without ADIM. The exercise was conducted 3 times a week for 4 weeks. Ultrasonography was used to measure the thickness of abdominal muscles. Balance ability was evaluated using Tetrax device. The Wilcoxon signed ranks test for comparison of pre and post values and Mann Whitney U test for comparison between groups were used.
RESULTS
After 4 weeks, there was a significant difference in the thickness of TrA between groups (p< 0.05) whereas no significant difference in IO and EO (p> 0.05). In stability values, the experimental group showed significant changes in stability indexes of standing with eyes open (NO) and standing on the pillow with eyes closed (PC) after the exercise period and there was a significant difference in NO between two groups.
CONCLUSIONS
Performing the bridging exercise with abdominal drawing-in maneuver is a more effective way to strengthen the abdominal muscles and stabilize the body than bridging exercise only.
Topics: Abdominal Muscles; Exercise; Exercise Therapy; Female; Healthy Volunteers; Humans; Male; Muscle Contraction; Standing Position; Ultrasonography; Young Adult
PubMed: 30010104
DOI: 10.3233/BMR-171080 -
Reproductive Sciences (Thousand Oaks,... Aug 2017Patient-controlled epidural analgesia (PCEA), used to relieve pain during delivery, delays labor but the mechanism is unknown. The aim was to investigate the effects of...
OBJECTIVE
Patient-controlled epidural analgesia (PCEA), used to relieve pain during delivery, delays labor but the mechanism is unknown. The aim was to investigate the effects of PCEA on uterine and abdominal muscles electromyographic (EMG) activity during the second stage of labor.
METHODS
This study included 45 nulliparous pregnant women without PCEA, 42 women with standard PCEA treatment given during the first stage of labor and stopped near the end of the first stage, and 22 women with standard PCEA treatment with continued use throughout the first and second stages of labor. The EMG signals were recorded from the abdominal surface using PowerLab hardware and LabChart software (ADInstruments, New South Wales, Australia) and filtered to separate uterine and abdominal EMG. Various EMG burst parameters were obtained.
RESULTS
There are no differences ( P > .05) in the age, body mass index, fetal weight, and Apgar scores between the patients from the various groups. PCEA (both stopped and continued) inhibits ( P < .05) duration, number of bursts, and root mean square of uterine EMG. PCEA also produces statistically significant ( P < .001) reductions in abdominal EMG. The decrease in EMG activity is accompanied by a significant ( P < .001) prolongation of the second stage duration (PCEA continued = 95.08 ± 8.60 minutes, PCEA stopped = 79.39 ± 6.25 minutes, no PCEA = 61.00 ± 7.23 minutes).
CONCLUSION
PCEA suppresses uterine and abdominal muscle EMG during the second stage of labor but inhibition depends upon the treatment schedule. PCEA prolongs the duration of labor by inhibition of uterine and abdominal muscle and neural activity.
Topics: Abdominal Muscles; Adult; Analgesia, Epidural; Analgesia, Patient-Controlled; Anesthetics, Local; Electromyography; Female; Humans; Labor Stage, Second; Myometrium; Pregnancy
PubMed: 28715964
DOI: 10.1177/1933719116682875 -
American Journal of Respiratory and... Mar 2000The abdominal muscles are completely paralyzed after traumatic transection of the cervical cord. To assess the residual pressure-generating capacity of these muscles, we...
The abdominal muscles are completely paralyzed after traumatic transection of the cervical cord. To assess the residual pressure-generating capacity of these muscles, we first measured the changes in gastric pressure (DeltaPga) during paired bilateral stimulation of the lower thoracic nerve roots in eight chronic patients with C5-C7 tetraplegia and eight matched unaffected subjects in the seated posture. Stimulations were applied with a 90-mm circular magnetic coil positioned at the level of T10 and connected to a Magstim 250 stimulator. During relaxation at FRC, DeltaPga during maximal stimulation averaged (mean +/- SE) 76.0 +/- 11.7 cm H(2)O in the control subjects, whereas in the patients it was only 29.9 +/- 3.7 cm H(2)O (p = 0.002). Stimulations were next applied during the course of a forced expiration. All patients consistently demonstrated an abrupt increase in esophageal pressure (22.7 +/- 4.5 cm H(2)O), and six of them also showed an increase in expiratory flow. The cumulative thickness of the four abdominal muscles, as measured with an ultrasound probe, was 34% smaller in the patients than in the control subjects and correlated positively with maximal DeltaPga. We conclude that in patients with tetraplegia, muscle atrophy causes a marked reduction in abdominal muscle strength. However, magnetic stimulation of the abdominal muscles elicits increases in intrathoracic pressure that are greater than those required to initiate dynamic airway compression; it might, therefore, improve the clearing of airway secretions.
Topics: Abdominal Muscles; Adult; Electromagnetic Fields; Humans; Isometric Contraction; Lung Volume Measurements; Male; Middle Aged; Mucociliary Clearance; Muscular Atrophy; Pulmonary Ventilation; Quadriplegia; Respiratory Paralysis; Spinal Cord Injuries; Spinal Nerve Roots
PubMed: 10712311
DOI: 10.1164/ajrccm.161.3.9906020 -
Journal of Strength and Conditioning... Nov 2006The swiss is widely used in the recreational training environment as a supplement to conventional resistance training. One such application is to use the swiss ball as a...
The swiss is widely used in the recreational training environment as a supplement to conventional resistance training. One such application is to use the swiss ball as a bench support for bench press exercise. There is no evidence to indicate that the use of a swiss ball is beneficial for resistance training exercise. This study investigated muscle activity using surface electromyography of upper-body and abdominal muscles during the concentric and eccentric phases of the bench press on and off a swiss ball. Volunteers for this study were 14 resistance-trained subjects who performed isolated concentric and eccentric bench press repetitions using the 2 test surfaces with a 2-second cadence at a load equivalent to 60% maximum force output. The average root mean square of the muscle activity was calculated for each movement, and perceived exertion during the tasks was collected using a Borg Scale. The results of the study showed that deltoid and abdominal muscle activity was increased for repetitions performed using the swiss ball. Increased deltoid muscle activity supports previous findings for increased activity when greater instability is introduced to the bench press movement. Abdominal muscle activity increases were not hypothesized, but this finding provides scientific evidence for anecdotal reasoning behind swiss ball use as a potential core stability training device.
Topics: Abdominal Muscles; Adult; Analysis of Variance; Cross-Over Studies; Electromyography; Female; Humans; Male; Muscle, Skeletal; Physical Education and Training; Physical Exertion; Weight Lifting
PubMed: 17194238
DOI: 10.1519/R-18085.1 -
American Journal of Respiratory and... Apr 1999We evaluated abdominal muscle contractility and fatigue by measuring twitch gastric pressure (Pgat) after percutaneous supramaximal electrical stimulation of the...
We evaluated abdominal muscle contractility and fatigue by measuring twitch gastric pressure (Pgat) after percutaneous supramaximal electrical stimulation of the abdominal wall before and after sit-ups to task failure. Mouth pressures during maximal voluntary expulsive maneuvers (PEmax) at TLC and FRC with superimposed twitches, and maximum voluntary ventilation (MVV) were also assessed. Mean fresh Pgat was 36.1 +/- 3.0 cm H2O with a coefficient of variation that ranged between 3.0 to 4.8%. Pgat decreased by 25% (p < 0.001) and 37% (p < 0.001) at 1 and 30 min after sit-ups. During maximal voluntary contraction twitch occlusion never occurred. PEmax at TLC and FRC decreased by 15% (p < 0.001) and 11% (p < 0.017) at 1 min, and 8% (p < 0.036) and 9% (p < 0.030) at 30 min after sit-ups, respectively. Despite the abdominal muscle fatigue, MVV values at 1 and 30 min after sit-ups were not significantly different from the value obtained before the sit-ups. We conclude that (1) Pgat is a useful objective indicator of abdominal muscle contractility and fatigue; (2) during maximal voluntary expulsive maneuvers the abdominal muscles are never fully activated; (3) sit-ups lead to substantial low-frequency fatigue but little high-frequency fatigue of the abdominal muscles, which has little effect on maximal breathing capacity.
Topics: Abdominal Muscles; Adult; Diaphragm; Electric Stimulation; Electromyography; Exercise; Functional Residual Capacity; Humans; Male; Maximal Voluntary Ventilation; Mouth; Muscle Contraction; Muscle Fatigue; Pressure; Pulmonary Ventilation; Respiratory Muscles; Total Lung Capacity
PubMed: 10194145
DOI: 10.1164/ajrccm.159.4.9803025