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Muscle & Nerve Sep 2006This study was undertaken to establish normal reference ranges for abdominal muscle size and symmetry and to examine the effects on these of gender and age. We studied...
This study was undertaken to establish normal reference ranges for abdominal muscle size and symmetry and to examine the effects on these of gender and age. We studied 123 subjects, consisting of 55 men (aged 21-72 years) and 68 women (aged 20-64 years). Real-time ultrasound imaging of the abdominal muscles was performed. Thickness of internal and external oblique (IO, EO), transversus abdominis (TA), and rectus abdominis (RA), and cross-sectional area (CSA) of RA were measured, and absolute and relative muscle thickness (percent total muscle thickness), order of thickness, and symmetry (percent difference between sides) were determined. Males had significantly larger muscles than females and size was poorly correlated with age. The pattern of relative muscle thickness was RA > IO > EO > TA. Symmetry for total absolute thickness of all three lateral muscles was 8%-9% (mean) but for individual muscles there was asymmetry of absolute size (13%-24%), whereas relative thickness was symmetrical for all muscles. These findings provide robust reference data for the abdominal muscles in normal males and females in order to enable comparison with clinical groups to assess abnormalities and establish sensitivity for evaluating the effectiveness of interventions.
Topics: Abdominal Muscles; Adult; Aged; Anthropometry; Female; Humans; Male; Middle Aged; Organ Size; Reference Values; Reproducibility of Results; Sex Factors; Ultrasonography
PubMed: 16775833
DOI: 10.1002/mus.20589 -
IEEE Journal of Biomedical and Health... Oct 2021Health professionals extensively use Two-Dimensional (2D) Ultrasound (US) videos and images to visualize and measure internal organs for various purposes including...
Health professionals extensively use Two-Dimensional (2D) Ultrasound (US) videos and images to visualize and measure internal organs for various purposes including evaluation of muscle architectural changes. US images can be used to measure abdominal muscles dimensions for the diagnosis and creation of customized treatment plans for patients with Low Back Pain (LBP), however, they are difficult to interpret. Due to high variability, skilled professionals with specialized training are required to take measurements to avoid low intra-observer reliability. This variability stems from the challenging nature of accurately finding the correct spatial location of measurement endpoints in abdominal US images. In this paper, we use a Deep Learning (DL) approach to automate the measurement of the abdominal muscle thickness in 2D US images. By treating the problem as a localization task, we develop a modified Fully Convolutional Network (FCN) architecture to generate blobs of coordinate locations of measurement endpoints, similar to what a human operator does. We demonstrate that using the TrA400 US image dataset, our network achieves a Mean Absolute Error (MAE) of 0.3125 on the test set, which almost matches the performance of skilled ultrasound technicians. Our approach can facilitate next steps for automating the process of measurements in 2D US images, while reducing inter-observer as well as intra-observer variability for more effective clinical outcomes.
Topics: Abdominal Muscles; Deep Learning; Humans; Observer Variation; Reproducibility of Results; Ultrasonography
PubMed: 34057902
DOI: 10.1109/JBHI.2021.3085019 -
The Journal of Orthopaedic and Sports... Aug 2013Experimental laboratory study.
STUDY DESIGN
Experimental laboratory study.
OBJECTIVES
To measure the activation patterns (onset and magnitude) of the abdominal muscles during a standing long jump using wire and surface electromyography.
BACKGROUND
Activation patterns of the abdominal muscles, especially the deep muscles such as the transversus abdominis (TrA), have yet to be examined during full-body movements such as jumping.
METHODS
Thirteen healthy men participated. Wire electrodes were inserted into the TrA with the guidance of ultrasonography, and surface electrodes were attached to the skin overlying the rectus abdominis (RA) and external oblique (EO). Electromyographic signals and video images were recorded while each subject performed a standing long jump. The jump task was divided into 3 phases: preparation, push-off, and float. For each muscle, activation onset relative to the onset of the RA and normalized muscle activation levels (percent maximum voluntary contraction) were analyzed during each phase. Comparisons between muscles and phases were assessed using 2-way analyses of variance.
RESULTS
The onset times of the TrA and EO relative to the onset of the RA were -0.13 ? 0.17 seconds and -0.02 ? 0.07 seconds, respectively. Onset of TrA activation was earlier than that of the EO. The activation levels of all 3 muscles were significantly greater during the push-off phase than during the preparation and float phases.
CONCLUSION
Consistent with previously published trunk-perturbation studies in healthy persons, the TrA was activated prior to the RA and EO. Additionally, the highest muscle activation levels were observed during the push-off phase.
Topics: Abdominal Muscles; Analysis of Variance; Electromyography; Humans; Male; Movement; Video Recording; Young Adult
PubMed: 23756356
DOI: 10.2519/jospt.2013.4420 -
Gait & Posture Nov 2006Anticipatory postural adjustments (APAs) are postulated to ameliorate the effects of the disturbance to posture caused by voluntary movement. The primary hypothesis...
Anticipatory postural adjustments (APAs) are postulated to ameliorate the effects of the disturbance to posture caused by voluntary movement. The primary hypothesis tested in our study was that the magnitude of anticipatory trunk muscle activity is altered by abdominal muscle fatigue. A subsidiary aim of the present study was to examine the directional nature of APAs and use this information to elucidate the central or peripheral nature of changes in postural muscle activity associated with abdominal muscle fatigue. The present study was a within subject design, where abdominal muscle fatigue was induced by a static abdominal curl. Surface EMG was used to assess postural muscle activity in the following trunk muscles; rectus abdominis, erector spinae and internal oblique. Following abdominal muscle fatigue, the magnitude of muscle activity during APAs was significantly reduced by 20% in both the rectus abdominis (fatigued muscle) and the erector spinae (not fatigued) indicating a central rather than peripheral fatigue effect on muscle activity. Abdominal muscle fatigue also induced a 30% increase in the baseline muscle activity of the internal oblique. The changes in magnitude of APA muscle activity may reflect a change in system gain or a change in postural control perhaps related to a change in perceived postural stability. An increase in baseline muscle activity in the internal oblique may compensate partially for the reduction in APAs.
Topics: Abdominal Muscles; Adolescent; Adult; Arm; Biomechanical Phenomena; Electromyography; Female; Humans; Linear Models; Male; Movement; Muscle Fatigue; Posture
PubMed: 16406623
DOI: 10.1016/j.gaitpost.2005.10.011 -
Respiratory Research Feb 2010In patients with chronic obstructive pulmonary disease, a restriction on maximum ventilatory capacity contributes to exercise limitation. It has been demonstrated that...
BACKGROUND
In patients with chronic obstructive pulmonary disease, a restriction on maximum ventilatory capacity contributes to exercise limitation. It has been demonstrated that the diaphragm in COPD is relatively protected from fatigue during exercise. Because of expiratory flow limitation the abdominal muscles are activated early during exercise in COPD. This adds significantly to the work of breathing and may therefore contribute to exercise limitation. In healthy subjects, prior expiratory muscle fatigue has been shown itself to contribute to the development of quadriceps fatigue. It is not known whether fatigue of the abdominal muscles occurs during exercise in COPD.
METHODS
Twitch gastric pressure (TwT10Pga), elicited by magnetic stimulation over the 10th thoracic vertebra and twitch transdiaphragmatic pressure (TwPdi), elicited by bilateral anterolateral magnetic phrenic nerve stimulation were measured before and after symptom-limited, incremental cycle ergometry in patients with COPD.
RESULTS
Twenty-three COPD patients, with a mean (SD) FEV1 40.8(23.1)% predicted, achieved a mean peak workload of 53.5(15.9) W. Following exercise, TwT10Pga fell from 51.3(27.1) cmH2O to 47.4(25.2) cmH2O (p = 0.011). TwPdi did not change significantly; pre 17.0(6.4) cmH2O post 17.5(5.9) cmH2O (p = 0.7). Fatiguers, defined as having a fall TwT10Pga > or = 10% had significantly worse lung gas transfer, but did not differ in other exercise parameters.
CONCLUSIONS
In patients with COPD, abdominal muscle but not diaphragm fatigue develops following symptom limited incremental cycle ergometry. Further work is needed to establish whether abdominal muscle fatigue is relevant to exercise limitation in COPD, perhaps indirectly through an effect on quadriceps fatigability.
Topics: Abdominal Muscles; Female; Humans; Male; Middle Aged; Muscle Contraction; Muscle Fatigue; Physical Exertion; Pulmonary Disease, Chronic Obstructive
PubMed: 20132549
DOI: 10.1186/1465-9921-11-15 -
Scientific Reports Jul 2023We aimed to assess the effects of interaction between several breathing patterns and postures on abdominal muscle activation and intra-abdominal pressure (IAP). This...
We aimed to assess the effects of interaction between several breathing patterns and postures on abdominal muscle activation and intra-abdominal pressure (IAP). This comparative cross-sectional study enrolled fourteen healthy university students majoring in sports science and/or physical education. They performed four active breathing tasks: quiet nasal breathing (Q-Bre), nasal deep breathing (Deep-Bre), completely forced expiration (Forced-Expi), and exertional nasal inhalation with abdominal muscles with isometric contraction (Exertion-Inspi) in the elbow-toe plank and supine postures. Breathing volume; IAP; and transverse abdominis-internal oblique muscle (TrA-IO) and external oblique muscle (EO) activities were recorded. Abdominal muscle activity and IAP significantly interacted with breathing pattern and postures during the expiratory phase (p < 0.05). In the inspiratory phase, TrA-IO activity was significantly affected by breathing pattern and EO activity with posture (p < 0.05). TrA-IO activity significantly increased during Forced-Expi in the supine posture (47.6% of the maximum voluntary contraction) and Exertion-Inspi in the elbow-toe posture (35.7%), whereas no differences were found during Deep-Bre or Q-Bre (< 20%). EO activity increased in the elbow-toe posture (22.5-30.6%) compared with that in the supine posture (< 5%) during all breathing tasks. IAP values were low during all tasks (< 15%) except for Forced-Expi (24.9%). Abdominal muscle activation and IAP interacted with the breathing pattern and posture.
Topics: Humans; Cross-Sectional Studies; Electromyography; Abdominal Muscles; Posture; Respiration; Muscle Contraction
PubMed: 37443166
DOI: 10.1038/s41598-023-37629-5 -
Medicina (Kaunas, Lithuania) Dec 2023: Abdominal muscle exercises with limb movements are more effective for trunk stabilization than traditional exercises involving trunk flexion alone. This study examined... (Randomized Controlled Trial)
Randomized Controlled Trial
: Abdominal muscle exercises with limb movements are more effective for trunk stabilization than traditional exercises involving trunk flexion alone. This study examined the effects of abdominal exercises incorporating sprinter pattern and crunch exercises on changes in the lordotic curve and abdominal muscle activation in individuals with low back pain caused by hyperlordosis resulting from weak abdominal muscles. : In this single-blind, randomized controlled trial, a total of 40 participants with hyperlordosis were recruited and randomly assigned to perform either sprinter-pattern abdominal exercises or crunch exercises. The participants assigned to each group performed three sets of ten abdominal exercises. The lumbar lordotic angle (LLA) and sacrohorizontal angle (SHA) were assessed prior to and following the intervention, whereas abdominal muscle activity was gauged throughout the intervention period. Changes in the LLA and SHA were measured by radiography. Abdominal muscle activity was measured using electromyography. : The LLA and SHA decreased significantly in both groups ( < 0.001), while the sprinter-pattern exercise group showed a statistically significant decrease compared to the crunch exercise group ( < 0.001). In the activity of the abdominal muscles, there was no significant difference in the rectus abdominis muscle between the two groups ( > 0.005). However, a significant difference between the external and internal oblique muscles was observed, and the activities of both muscles were significantly higher in the sprinter-pattern exercise group than in the crunch exercise group ( < 0.005). : Abdominal exercise using a sprinter pattern may be effective in reducing lumbar lordosis by strengthening the abdominal muscles in patients with hyperlordosis.
Topics: Humans; Lordosis; Single-Blind Method; Abdominal Muscles; Exercise; Rectus Abdominis
PubMed: 38138280
DOI: 10.3390/medicina59122177 -
The Journal of Sports Medicine and... Feb 2020Neuromuscular electrical stimulation (NMES) devices for abdominal muscles are being marketed to the general public to improve physical appearance. Abdominal muscles play...
BACKGROUND
Neuromuscular electrical stimulation (NMES) devices for abdominal muscles are being marketed to the general public to improve physical appearance. Abdominal muscles play an important role in lumbopelvic stability for optimizing performance. We investigated the effects of NMES training of abdominal muscles on muscle size, muscle strength, endurance, and lumbopelvic stability.
METHODS
Twenty-three subjects (12 females, 11 males) performed abdominal muscle NMES training for 8 weeks. Before and after NMES training, we measured muscle size (cross-sectional area [CSA] of the rectus abdominals [RA] and lateral abdominal wall [LAW]) by magnetic resonance imaging, muscle strength (trunk flexor and side bridge strength), endurance (trunk flexor and side bridge endurance time), and lumbopelvic stability (one-leg loading test).
RESULTS
There were significant increases between pre- and post-NMES training differences in the size (CSA of RA 21.7-25.4%, P<0.001; CSA of LAW 9.00-9.71%, P<0.001), strength (trunk flexor 14.9%, P<0.05; side bridge 33.7-53.6%, P<0.05), and endurance (trunk flexor 29.1%, P<0.05; side bridge 24.6-28.9%, P<0.05) of abdominal muscles and lumbopelvic stability (37.2-37.4%, P<0.05).
CONCLUSIONS
NMES training could be applied to increase muscle size and muscle performances of abdominal muscles in sports and fitness fields.
Topics: Abdominal Muscles; Adult; Electric Stimulation; Exercise Therapy; Female; Humans; Magnetic Resonance Imaging; Male; Muscle Strength; Young Adult
PubMed: 32125124
DOI: 10.23736/S0022-4707.19.09998-5 -
Journal of Physiological Anthropology Aug 2016Real-time ultrasound imaging is a valid method in the field of rehabilitation. The ultrasound imaging allows direct visualization for real-time study of the muscles as...
BACKGROUND
Real-time ultrasound imaging is a valid method in the field of rehabilitation. The ultrasound imaging allows direct visualization for real-time study of the muscles as they contract over the time. Measuring of the size of each abdominal muscle in relation to the others provides useful information about the differences in structure, as well as data on trunk muscle activation patterns. The purpose of this study was to assess the size and symmetry of the abdominal muscles at rest in healthy adults and to provide a reference range of absolute abdominal muscle size in a relatively large population.
METHOD
A total 156 healthy subjects with the age range of 18-44 years were randomly recruited. The thickness of internal oblique, external oblique, transverse abdominis, and rectus abdominis muscles was measured at rest on both right and left sides using ultrasound. Independent t test was used to compare the mean thickness of each abdominal muscle between males and females. Differences on side-to-side thicknesses were assessed using paired t test. The association between abdominal muscle thicknesses with gender and anthropometric variables was examined using the Pearson correlation coefficient.
RESULTS
A normal pattern of increasing order of mean abdominal muscle thickness was found in both genders at both right and left sides: transverse abdominis < external oblique < internal oblique < rectus abdominis. There was a significant difference on the size of transverse abdominis, internal oblique, and external oblique muscles between right and left sides in both genders. Males had significantly thicker abdominal muscles than females. Age was significantly correlated with the thickness of internal oblique, external oblique, and rectus abdominis muscles. Body mass index was also positively correlated with muscle thickness of rectus abdominis and external oblique.
CONCLUSIONS
The results provide a normal reference range for the abdominal muscles in healthy subjects and may be used as an index to find out abnormalities and also to evaluate the effectiveness of different interventions.
Topics: Abdominal Muscles; Adolescent; Adult; Aging; Body Mass Index; Female; Humans; Male; Sex Factors; Ultrasonography; Young Adult
PubMed: 27553830
DOI: 10.1186/s40101-016-0106-6 -
The American Journal of Gastroenterology Apr 2001Recurrent episodes of bloating and visible abdominal distension are common and distressing in irritable bowel syndrome, but the mechanisms are unknown. Patients often...
OBJECTIVE
Recurrent episodes of bloating and visible abdominal distension are common and distressing in irritable bowel syndrome, but the mechanisms are unknown. Patients often note that the distension is most pronounced in the upright posture, suggesting that the bloating may be the result of a decrease or absence of the normal rise in electromyograph activity in the abdominal wall muscles when standing. There are no reports of noninvasive electromyograph recordings of abdominal wall muscles in irritable bowel syndrome. We examined the hypothesis that abdominal distension is the result of relaxation of anterior abdominal wall musculature.
METHODS
Studies were performed on patients with irritable bowel syndrome and a history of visible distension (n = 11, mean age 48.6 yr, body mass index 24.8) and normal volunteers (n = 13, mean age 39.9 yr, body mass index 24.6). Surface recordings of muscle activity were made while subjects were lying, performing voluntary contraction of the abdominal wall, and standing. The examiners were blind as to the clinical status of the subjects.
RESULTS
There were no differences in abdominal wall muscle activity (by electromyograph voltage) when comparing patients with irritable bowel syndrome to normal volunteers (e.g., relaxed lower abdomen supine mean electromyograph voltage in irritable bowel syndrome was 14.0 vs 14.6 in controls, p = 0.7, and relaxed lower abdomen standing in irritable bowel syndrome was 29.6 vs 25.2 in controls, p = 0.4). There was increased activity in both groups when contracting the muscles and when standing.
CONCLUSIONS
Patterns of abdominal wall muscle activity do not differ between normal subjects and patients with irritable bowel syndrome. However, there is a clear increase in muscle activity in the standing position. Episodic distension is unlikely to be due to permanent anterior abdominal muscle weakness or a persistent inability of the muscles to activate with standing in irritable bowel syndrome.
Topics: Abdominal Muscles; Adult; Colonic Diseases, Functional; Electromyography; Female; Humans; Middle Aged
PubMed: 11316160
DOI: 10.1111/j.1572-0241.2001.03761.x