Deep Trunk Muscles Research Articles

Relationship Between the Results of the Landing Error Scoring System and Trunk Muscle Thickness.

A landing error scoring system (LESS) is widely used to evaluate landing maneuvers. Poor landing maneuvers, such as lateral bending of the trunk, are thought to be associated with a risk of lower-extremity injury. However, no studies have examined the association between landing and trunk muscle function, which is associated with a high risk of lower-extremity injury. This study examined whether an association exists between landing movements and a high risk of lower-extremity injury and trunk muscle function. It was hypothesized that athletes with poor activation of deep trunk muscle (transversus abdominis and internal oblique) would have lower LESS scores. Cross-sectional study. The trunk muscle thickness at rest and during the plank was measured using ultrasonography. The percent of change in muscle thickness (during plank/at rest) was calculated. The LESS was measured using the Physimax. Based on the LESS scores, patients were divided into high- (LESS > 6) and low-risk (5 > LESS) groups for lower extremity injury. The relationship between the high-risk group and trunk muscle thickness was examined using a stepwise regression analysis. The high-risk group had significantly lower muscle thicknesses of the transversus abdominis (p=0.02) and transversus abdominis plus internal oblique abdominis (p=0.03) muscles during the plank. Additionally, the high-risk group showed significantly lower percent of change in muscle thickness of the internal oblique (p=0.02) and transversus abdominis plus internal oblique (p=0.01) muscles. Only the percentage of change in the thickness of the internal oblique and transverse abdominal muscles was extracted from the regression as a factor. The findings indicated that athletes with landing movements and a high risk of injury, as determined based on the LESS results, had low trunk muscle function, and a relationship was observed between the change in thickness of transversus abdominis and internal oblique abdominis muscles. 3B.

Activity of deep trunk muscles for postural control to predictable and unpredictable sagittal plane perturbations: Electromyographic analysis.

The activity of deep trunk muscles (psoas major; PM, quadratus lumborum; QL, transverse abdominis; TrA, and lumbar multifidus; MF) in response to external perturbation is not clearly known. This study aimed to record the onset and amount of activity of the deep trunk muscles during sagittal plane perturbations. Fourteen healthy males participated in this study. The activity of the right deep trunk muscles was recorded using wire electrodes. In standing, the participants performed three tasks: a pendulum impacted from anterior with predictable and unpredictable and posterior with unpredictable. In predictable anterior perturbation, the TrA and PM demonstrated feedforward activation, while all deep trunk muscles demonstrated feedback activation in unpredictable anterior and posterior perturbations. In the anticipatory postural adjustment phase, the activity of the TrA was large in predictable anterior perturbation, while that of all deep trunk muscles was slight in other perturbations. In the compensatory postural adjustment phase, the activity of the PM, QL, and TrA in unpredictable anterior perturbation and those of the PM, QL, and MF in unpredictable posterior perturbation were large. These results showed that the onset and magnitude of deep trunk muscle activity changed depending on both predictable or unpredictable perturbation and the direction of perturbation.

Efficacy of Core Muscle Stabilization in Chronic Nonspecific Low Back Pain Patients – A Systematic Review

Background: Low back pain referred as pain localized between the 12th rib and the inferior gluteal folds with included leg pain sometimes not, most cases are nonspecific but in about 10% of cases a specific cause is identified. The major causes of low back pain are weakness of superficial trunk muscles, abdominal muscles and motor control or delayed activation of deep muscles (multifidus and transversus abdominis). Hence Core Stabilization exercise provides greater support to the spine, control of lumbar deep muscles and pelvis, and integration of activity of superficial and deep trunk muscles. Aim:The aim of the study is to determine the efficacy of core muscle stabilization exercise in chronic nonspecific low back pain patients. Search Method: Studies were collected from databases Google scholar, PubMed, Cochrane library, Research gate, CINAHL Medicine. Methodology: Inclusion criteria was Randomized or quasi-randomized controlled trial studies and Experimental study design. Sample size was 245 articles, 188 articles were collected from Google scholar, 28 articles from PubMed, and 29 articles from Cochrane library. Methodology of the Study was designed as Systematic review. Results: Out of 245 published studies, we selected 14 articles which describing about efficacy of core muscle stabilization exercise in chronic nonspecific low back pain, among which 8 articles discussed about the effectiveness of core stabilization exercise, 2 articles about lumbar stabilization, 2 articles about Pilates based exercise, 2 articles about segmental stabilization in reducing chronic nonspecific low back pain. Conclusion: By reviewing the study, we conclude that core muscle stabilization exercise is effective in reducing the chronic nonspecific low back pain (CNSLBP).

Comparison of Muscle Activity and Muscle Thickness According to Knee Flexion Angle during Supine Bridge Exercises using the Abdominal Drawing-in Maneuver on an Unstable Surface.

This study evaluated changes in deep trunk muscle thickness and lower extremity muscle activities during bridge exercises with the abdominal drawing-in maneuver. Bridge exercises were conducted on an unstable surface at different knee flexion angles (60º, 90º and 120º), with the aim of identifying more effective angles for bridge exercises. This study included 21 healthy adults, aged 20-27 years. Biceps femoris (BF), rectus abdominis, and rectus femoris activity was measured using surface electromyography. The thicknesses of the transverse abdominis (TrA), external oblique (EO) and internal oblique (IO) muscles were measured. BF (p = 0.000, partial η2 = 0.670) activity increased considerably as the knee flexion angle decreased. TrA (p = 0.000, partial η2 = 0.883) and IO (p = 0.000, partial η2 = 0.892) thickness significantly increased, while EO (p = 0.000, partial η2 = 0.893) thickness decreased as the knee flexion angle decreased. When performing bridge exercises using the abdominal drawing-in maneuver on an unstable surface, the knee flexion angles should be at 120º and 60º to increase trunk stability and lower extremity muscle activity, respectively.

Diaphragmatic breathing exercises in recovery from fatigue-induced changes in spinal mobility and postural stability: a study protocol.

Prolonged periods of sitting at work can increase trunk muscle fatigue from the continuous contraction of deep trunk muscles. Insufficient activity of these muscles can decrease muscular support to the spine and increases stress on its passive structures. This can lead to reduced spinal mobility and impaired postural stability. It may also stimulate nociceptor activity leading to pain. However, frequently used recovery modalities such as muscle strengthening and stretching exercises, can be time-consuming, impractical, and difficult to implement in the workplace. Diaphragmatic breathing exercises, which increase the activity of the deep trunk muscles by raising intra-abdominal pressure, seem to be a suitable alternative. However, little is known as to what extent diaphragmatic breathing exercises contribute to the reduction of fatigue induced by prolonged sitting. This paper presents a study protocol that aims to investigate the acute effect of diaphragmatic breathing exercises on recovery of fatigue-induced changes in spinal mobility and postural stability in sedentary middle-aged adults at risk of developing non-specific low back pain. Twenty sedentary adults aged between 25 and 44years will perform Abt's fatigue protocol, followed by 1) active recovery using diaphragmatic breathing exercises and 2) passive recovery in the form of lying on the bed, respectively. There will be 1week of rest in-between. Pre-fatigue, post-fatigue, and after the active and passive recovery, spinal mobility and postural stability will be evaluated using the spinal mouse device and a posturography system, respectively. The electromyography will be used to determine the muscle-fatigue conditions. We hypothesize that active recovery in a form of diaphragmatic breathing exercises would be more effective in restoring spinal mobility and postural stability followed by the fatigue of back and hamstring muscles compared to passive recovery in sedentary adults. Increasing core and respiratory muscle strength via these exercises could be beneficial for overall mobility and stability of the spine. Reducing compressive stress on the passive structures of the spine may be also beneficial for lowering low back pain. Therefore, we believe that diaphragmatic breathing exercises have the possibility to be incorporated into the workplace and contribute to better back health in sedentary middle-aged adults. Clinical Trial Registration: [https://www.irct.ir/trial/67015], identifier [IRCT20221126056606N1].

Effects of 6 weeks of ankle stability exercises on pain, functional abilities, and flexibility in patients with chronic non-specific low back pain: a randomized controlled trial

BackgroundDue to delayed activation of the deep trunk muscles, patients with chronic non-specific low back pain use different adjustment strategies to maintain postural control. Patients with chronic non-specific low back pain maintain a quite standing posture during pain episode and challenging activities by using signals from other joints, mainly the ankle joint. Since proprioceptive signals from the ankle joint reduce postural control variability in patients with chronic non-specific low back pain, this study explored whether ankle stability exercises added to traditional physical therapy exercises would improve the intensity of pain, functional disabilities and lumbar flexion range of motion in patients with chronic non-specific low back pain.MethodsSixty patients with chronic non-specific low back pain participated in the current study. Patients were randomly assigned into two groups: group A and group B. Patients in group A received traditional physical therapy exercises for low back pain. Patients in group B received the same traditional physical therapy exercises as patients in group A, plus ankle stability exercises. The intensity of pain, functional disability, and lumbar flexion range of motion were assessed twice before and after a 6-week period during which each group received their interventions.ResultsMixed design MANOVA revealed a significant decrease in visual analog scale and Oswestry Disability Index in group B compared to group A post treatment (p < 0.05). Moreover, there was a significant increase in the lumbar flexion range of motion in group B compared with group A post treatment (p < 0.05).ConclusionThe findings of this study revealed that adding ankle stability exercises to the traditional physical therapy exercises significantly improved pain, Oswestry Disability Index, and lumbar flexion range of motion in patients with chronic non-specific low back pain. Thus, ankle strengthening and proprioceptive exercises may be beneficial in the management of chronic non-specific low back pain.

Ultrasonography Comparison of Diaphragm Morphological Structure and Function in Young and Middle-Aged Subjects with and without Non-Specific Chronic Low Back Pain: A Case-Control Study.

It is reported that impaired postural control in patients with non-specific chronic low back pain (NCLBP) was associated with "core" trunk muscle incoordination. However, as the diaphragm is an important component of the "core" deep trunk muscle group, we still know little about the potential relationship between diaphragm dysfunction and NCLBP. This case-control study is intended to investigate the changes of diaphragm morphological structure and function in young and middle-aged subjects with and without NCLBP by ultrasound evaluation and its possible validity in predicating the occurrence of NCLBP. 31 subjects with NCLBP (NCLBP group) and 32 matched healthy controls (HC group) were enrolled in this study. The diaphragm thickness at the end of inspiration (T ins) or expiration (T exp) during deep breathing was measured through B-mode ultrasound, and the diaphragm excursion (T exc) was estimated at deep breathing through M-mode ultrasound. The diaphragm thickness change rate (T rate) was calculated by the formula: T rate=(T ins - T exp)/T exp × 100%. Compared with the HC group, the NCLBP group had a significant smaller degree of Tins (t = -3.90, P < 0.001), T exp (Z = -2.79, P=0.005), and T rate (t = -2.03, P=0.047). However, there was no statistical difference in T exc between the two groups (t = -1.42, P=0.161). The binary logistic regression analysis indicated that T rate (OR = 16.038, P=0.014) and T exp (OR = 7.714, P=0.004) were potential risk factors for the occurrence of NCLBP. The diaphragm morphological structure and function were changed in young and middle-aged subjects with NCLBP, while the diaphragm thickness change rate (T rate) and diaphragm thickness at the end of expiration (T exp) may be conductive to the occurrence of NCLBP. Furthermore, these findings may suggest that abnormal diaphragm reeducation is necessary for the rehabilitation of patients with NCLBP.

Numerical Identification of Deep Muscle Residual Tensions (Tones) Based on Multi-Directional Trunk Stiffness Data

This work proposes an identification methodology to estimate the residual tension values (tones) for the human trunk muscles, including the deep ones, using multidirectional trunk stiffness data in association with numerical modeling. The role of this residual muscle tension or contraction is to maintain posture and balance. Knowledge of the tone is useful for the diagnosis and treatment of several spinal diseases and is important for realistic modeling and numerical simulation of trunk behavior. Most of the existing techniques for the measurement and estimation of muscle tones, such as electromyography, are restricted to superficial muscles. Those designed for deep muscles are invasive and present risks of infection and pain. In contrast, the proposed identification approach is painless and safe for the subject. It proceeds by matching the experimental trunk stiffness with numerical upper and lower estimates of the stiffness, to construct an inclusive solution domain of possible tone values of superficial as well as deep trunk muscles. By dividing the trunk muscles into three classes, each assumed to share the same tone ratio, a reasonable solution domain is obtained that exhibits a significant overlap with ranges of muscle tones found in the literature.

The Influence of Anticipation of Movement Starting Time on Feedforward Activation of Trunk Muscles during Rapid Shoulder Joint Movements.

This study aimed to clarify the differences in the onset of trunk muscle activity with and without anticipation of the movement starting time during rapid shoulder movements. Ten healthy men in a relaxed upright position performed rapid 135° flexion, 135° abduction, and 45° extension of the shoulder on the dominant hand side with and without anticipation of the movement starting time. They moved their shoulder joints following a 3-s countdown and a light stimulus in the anticipation and non-anticipation conditions, respectively. Electromyography of the anterior and posterior quadratus lumborum, transversus abdominis, internal oblique, external oblique, rectus abdominis, lumbar multifidus, lumbar erector spinae on the non-dominant hand side, and the middle deltoid on the dominant hand side were measured. The onset of activity of each trunk muscle relative to the onset of the middle deltoid was calculated. Two-way analysis of variance (eight trunk muscles × two anticipation conditions) was used to compare the onset of electromyographic activity of the trunk muscles in each direction of the shoulder movement. There were significant interactions between the muscles and anticipation conditions during shoulder abduction and extension. The onset of activity in the anterior and posterior quadratus lumborum, transversus abdominis, and internal oblique occurred earlier with anticipation of the movement starting time than without anticipation during shoulder abduction and extension. The anticipation of movement starting time may contribute to a reliable center of mass control within the support base and improve lumbar spine stability by hastening the onset of activity of the deep trunk muscles.

Effect of direct vibration on the activity of deep trunk muscles of patients with non-specific chronic low back pain.

Vibration training is an adjuvant to muscle-strengthening exercises. To investigate the short-term effects of direct vibration on the deep trunk muscles of patients with non-specific chronic low back pain (CLBP). Participants with non-specific CLBP were randomly placed into two groups: the vibration-plus stabilization exercise (VSE) group (n= 31) and the conventional stabilization exercise (CSE) group (n= 31). The groups underwent 12 sessions of an exercise program. The thickness and activity of the trunk muscles were measured using ultrasonography and surface electromyography. Ultrasonography revealed that the ratio of muscle thickness to contraction and relaxation was statistically increased after exercise in the bilateral transversus abdominis (TrA) and lumbar multifidus (LM) muscles in the CSE group (p= 0.031), and in the bilateral TrA, LM, and internal oblique (IO) muscles in the VSE group (p< 0.001). The LM/lumbar erector spinae (LES) ratio in the CSE group (p= 0.037), and the IO/rectus abdominis (RA), TrA/RA, and LM/LES ratios in the VSE group (p= 0.019) were statistically increased. Multiple regression analysis showed that symptom improvement was related to increased activity of the deep trunk muscles in the VSE group (p< 0.001). Direct vibration can increase the selective activity of contracting deep trunk muscles.

Sex-Related Pain Behavioral Differences following Unilateral NGF Injections in a Rat Model of Low Back Pain.

Simple SummaryLow back pain (LBP) is a worldwide problem that requires additional studies to better identify its underlying causes. One obstacle encountered is that female-experienced LBP is likely biologically different from male-experienced LBP. Studying the potential sex-differences in animal models may provide a better understanding of the causes of LBP and help to identify new treatments for LBP. We used an animal model to investigate the differences in male and female rats when back muscles on one side were injected with a painful substance called nerve growth factor (NGF). These injections led to sex differences in the behavioral responses to painful stimuli (hyperalgesia) and non-painful stimuli (mechanical hypersensitivity). Ipsilateral low back deep hyperalgesia and superficial mechanical hypersensitivity lasted longer in females compared with males. Moreover, female rats had bilateral deep mechanical hyperalgesia and cutaneous trunk mechanical hypersensitivity, unlike males. Our results are the first to demonstrate that there are sex differences in an animal model of LBP induced by the painful substance NGF. Future studies may help to reveal the underlying biological mechanisms of LBP to create better treatments to attempt to help those suffering with LBP.Low back pain (LBP) is a globally prevalent and costly societal problem with multifactorial etiologies and incompletely understood pathophysiological mechanisms. To address such shortcomings regarding the role of neurotrophins in the underlying mechanisms of pain, an LBP model was developed in rats involving two unilateral intramuscular injections of nerve growth factor (NGF) into deep trunk muscles. To date, behavioral investigations of this NGF-LBP model have been limited, especially as it pertains to female pain behaviors. This study compared mechanical sensitivity to noxious (hyperalgesia) and non-noxious (hypersensitivity) stimuli in control and NGF-injected male and female rats through pain resolution. Although the baseline testing revealed no differences between males and females, NGF-injected females demonstrated prolonged ipsilateral deep trunk mechanical hyperalgesia that resolved seven days later than males. Moreover, females showed bilateral trunk mechanical sensitivity to noxious and non-noxious stimuli compared to only ipsilateral behaviors in males. Sex differences were also observed in the severity of behavioral responses, with females displaying greater mean differences from baseline at several timepoints. Overall, these NGF-LBP behavioral findings mirror some of the sex differences reported in the clinical presentation of LBP and accentuate the translatability of this NGF-LBP model. Future studies using this LBP-NGF model could help to elucidate the neurobiological mechanisms responsible for the development, severity, and/or resolution of muscular LBP as well as to provide insights into the processes governing the transition from acute to chronic LBP.

Immediate changes in chest mobility and trunk muscle activity during pelvic tilt following different trunk muscle exercises.

Given the characteristics of the superficial trunk muscles that cross the chest and pelvis, their excessive contraction might limit chest mobility. To examine the immediate effects of two types of trunk muscle exercises on chest mobility and trunk muscle activities. Fourteen healthy men (age: 21.1 ± 1.0 years, height: 172.7 ± 5.6 cm, weight: 61.0 ± 7.1 kg, body mass index: 20.4 ± 1.7 kg/m2; mean ± SD) randomly performed trunk side flexion and draw-in exercises using a cross-over design. The chest kinematic data and trunk muscle activities were measured before and after each intervention during the following tasks: maximum inspiration/expiration and maximum pelvic anterior/posterior tilt while standing. Two-way repeated measures analysis of variance was used for statistical analysis (P< 0.05). After the side flexion, upper and lower chest mobility significantly decreased, and superficial trunk muscle activity significantly increased during the maximum pelvic anterior tilt (P< 0.05). Additionally, after the draw-in, upper chest mobility significantly increased during the maximum pelvic anterior tilt (P< 0.05). Increased activity of the superficial abdominal muscles might limit chest mobility during maximum pelvic anterior tilt. Conversely, the facilitation of deep trunk muscles might increase upper chest mobility during the maximum pelvic anterior tilt.

Feedforward coactivation of trunk muscles during rapid shoulder movements.

BackgroundShoulder movements that involve unilateral and bilateral flexion, extension, abduction, and asymmetrical flexion-extension cause the activity of trunk muscles. There has not been a fixed consensus on the onset of deep trunk muscle activities including the psoas major (PM), quadratus lumborum (QL), transversus abdominis (TrA), and lumbar multifidus (MF) during shoulder movements. The purpose of this study was to measure the onset of electromyographic activity of the deep trunk muscles during rapid shoulder movements and clarify the coordinated activity pattern of the deep trunk muscles during 11 shoulder movements.MethodsThirteen men participated in this study. The onset of activity of the right deep trunk muscles (PM, QL, TrA, and MF) were measured using fine-wire electrodes, and those of the right and left deltoid (anterior, middle, and posterior) and right superficial trunk muscles (rectus abdominis, external oblique [EO], and internal oblique [IO]) were measured using surface electrodes as participants performed 6 types of unilateral, 3 types of bilateral, and 2 types of asymmetrical rapid shoulder movements. We defined feedforward activation as the onset of activity of trunk muscle before or within +50 ms onset of the deltoid muscle and feedback activation as that after +50 ms. A 1-way analysis of variance was performed to compare the onset of activity of each muscle during each shoulder movement.ResultsThe mean onset of activity of the PM (26.0 ms), QL (13.1 ms), TrA (−19.7 ms), and MF (20.4 ms) muscles demonstrated feedforward activation during left shoulder flexion. The onset of activity of the TrA (1.6-48.7 ms), rectus abdominis (−1.7 to 17.3 ms), and EO (5.6–40.8 ms) muscles demonstrated feedforward activation during left, right, and bilateral shoulder extension. The onset of activity of the PM (22.9 ms), QL (23.0 ms), TrA (18.9 ms), and EO (15.4 ms) demonstrated feedforward activation during left shoulder abduction, while that of the IO (4.4–10.9 ms) only demonstrated feedforward activation during right and bilateral shoulder abduction. The onset of activity of the TrA (−27.6 ms) and IO (−23.9 ms) demonstrated feedforward activation during left shoulder flexion-right shoulder extension, and that of the MF (33.4 ms) and EO (−17.2 ms), during left shoulder extension-right shoulder flexion.ConclusionRapid shoulder movements occur with coordinated muscle activation of the deep trunk muscles depending on the direction of shoulder movements. Feedforward activation of single or combined deep trunk muscles may facilitate rapid shoulder movements.

The Effect of Core Stabilization Exercise with the Abdominal Drawing-in Maneuver Technique on Stature Change during Prolonged Sitting in Sedentary Workers with Chronic Low Back Pain.

To enhance stature recovery, lumbar spine stabilization by stimulating the deep trunk muscle activation for compensation forces originating from the upper body was introduced. The abdominal drawing-in maneuver (ADIM) technique has been found mainly to activate deep trunk muscles. The purpose of the current study was to determine whether 5 weeks of training of deep trunk muscles using the ADIM technique could improve stature recovery, delay trunk muscle fatigue, and decrease pain intensity during prolonged sitting. Thirty participants with chronic low back pain (CLBP) conducted a core stabilization exercise (CSE) with the ADIM technique for 5 weeks. Participants were required to sit for 41 min before and after the exercise intervention. Stature change was measured using a seated stadiometer with a resolution of ±0.006 mm. During sitting, the stature change, pain intensity, and trunk muscle fatigue were recorded. A comparison between measurements at baseline and after 5 weeks of training demonstrated: (i) stature recovery and pain intensity significantly improved throughout the 41 min sitting condition; (ii) the bilaterally trunk muscle showed significantly decreased fatigue. The CSE with the ADIM technique was shown to provide a protective effect on detrimental reductions in stature change and trunk muscle fatigue during prolonged sitting in young participants under controlled conditions in a laboratory. This information may help to prevent the risk of LBP from prolonged sitting activities in real life situations.

FMS assessment and core stability in a group of amateur climbers

Background: The objective of the study was to assess the functional status of people who regularly climb for recreational purposes, using the FMS (Functional Movement Screen) and core stability tests (McGill's torso muscular endurance tests). This paper also attempts to determine the relation between the assessment of functional efficiency and the results obtained in core stability tests. Material and methods: The study group were consisted of 30 amateur climbers (aged 26 ±3), who were compared to a control group of 30 people who don’t climb but recreationally practice volleyball (aged 22 ±3). All participants performed each of the seven FMS trials and the three McGill's tests. Results: Amateur climbers, in comparison to non-climbers, were achieved higher scores in each of the core stability trials (p&lt;0,05). Climbers also scored significantly higher results in all FMS trials as well as in the final average (19,0 3 ±1,54 vs. 16,60 ±3,60; p&lt;0,01). In addition, there were found positive correlations between FMS and core stability trials in the group of climbers (Deep Squad vs. Side bridge test; In-Line Lunge vs. Side bridge test; Rotational Stability vs. all trials of the core stability test). Conclusions: People recreational practicing climbing are characterized by a high level of functional efficiency and above-average levels of deep trunk muscles endurance, responsible for the proper functioning of the central stabilization. Relationship between the overall results of the FMS and the core stability tests in the climbers' group shows that proper stability training, which is a part of the climbers training, may result in higher athletes’ performance.

Does Motor Control Exercise Restore Normal Morphology of Lumbar Multifidus Muscle in People with Low Back Pain? - A Systematic Review.

Aberrant morphological changes in lumbar multifidus muscle (LMM) are prevalent among patients with low back pain (LBP). Motor control exercise (MCE) aims to improve the activation and coordination of deep trunk muscles (eg, LMM), which may restore normal LMM morphology and reduce LBP. However, its effects on LMM morphology have not been summarized. This review aimed to summarize evidence regarding the (1) effectiveness of MCE in altering LMM morphometry and decreasing LBP; and (2) relations between post-MCE changes in LMM morphometry and LBP/LBP-related disability. Cumulative Index to Nursing and Allied Health Literature, MEDLINE, Cochrane Central Register of Controlled Trials, the Physiotherapy Evidence Database, EMBASE and SPORTDiscus were searched from inception to 30 September 2020 to identify relevant randomized controlled trials. Two reviewers independently screened articles, extracted data, and evaluated risk of bias and quality of evidence. Four hundred and fifty-one participants across 9 trials were included in the review. Very low-quality evidence supported that 36 sessions of MCE were better than general physiotherapy in causing minimal detectable increases in LMM cross-sectional areas of patients with chronic LBP. Very low- to low-quality evidence suggested that MCE was similar to other interventions in increasing resting LMM thickness in patients with chronic LBP. Low-quality evidence substantiated that MCE was significantly better than McKenzie exercise or analgesics in increasing contracted LMM thickness in patients with chronic LBP. Low-quality evidence corroborated that MCE was not significantly better than other exercises in treating people with acute/chronic LBP. Low-quality evidence suggested no relation between post-MCE changes in LMM morphometry and LBP/LBP-related disability. Collectively, while MCE may increase LMM dimensions in patients with chronic LBP, such changes may be unrelated to clinical outcomes. This raises the question regarding the role of LMM in LBP development/progression.

The Effects of Core Stabilization Exercise with the Abdominal Drawing-in Maneuver Technique versus General Strengthening Exercise on Lumbar Segmental Motion in Patients with Clinical Lumbar Instability: A Randomized Controlled Trial with 12-Month Follow-Up.

Trunk stability exercises that focus on either deep or superficial muscles might produce different effects on lumbar segmental motion. This study compared outcomes in 34 lumbar instability patients in two exercises at 10 weeks and 12 months follow up. Participants were divided into either Core stabilization (deep) exercise, incorporating abdominal drawing-in maneuver technique (CSE with ADIM), or General strengthening (superficial) exercise (STE). Outcome measures were pain, muscle activation, and lumbar segmental motion. Participants in CSE with ADIM had significantly less pain than those in STE at 10 weeks. They showed significantly more improvement of abdominal muscle activity ratio than participants in STE at 10 weeks and 12 months follow-up. Participants in CSE with ADIM had significantly reduced sagittal translation at L4-L5 and L5-S1 compared with STE at 10 weeks. Participants in CSE with ADIM had significantly reduced sagittal translations at L4-L5 and L5-S1 compared with participants in STE at 10 weeks, whereas STE demonstrated significantly increased sagittal rotation at L4-L5. However, at 12 months follow-up, levels of lumbar sagittal translation were increased in both groups. CSE with ADIM which focuses on increasing deep trunk muscle activity can reduce lumbar segmental translation and should be recommended for lumbar instability.

The Effects of Abdominal Hypopressive Training on Postural Control and Deep Trunk Muscle Activation: A Randomized Controlled Trial.

Background: Abdominal Hypopressive Training (AHT) provides postural improvement, and enhances deep trunk muscle activation. However, until recently, there was a lack of scientific literature supporting these statements. The major purpose of this study was to investigate the effect of AHT on posture control and deep trunk muscle function. Methods: 125 female participants aged 18–60 were randomly allocated to the Experimental Group (EG), consisting of two sessions of 30 min per week for 8 weeks of AHT, or the Control Group (CG), who did not receive any treatment. Postural control was measured with a stabilometric platform to assess the static balance and the activation of deep trunk muscles (specifically the Transverse Abdominal muscle (TrA)), which was measured by real-time ultrasound imaging. Results: The groups were homogeneous at baseline. Statistical differences were identified between both groups after intervention in the Surface of the Center of Pressure (CoP) Open-Eyes (S-OE) (p = 0.001, Cohen’s d = 0.60) and the Velocity of CoP under both conditions; Open-Eyes (V-OE) (p = 0.001, Cohen´s d = 0.63) and Close-Eyes (V-CE) (p = 0.016, Cohen´s d = 0.016), with the EG achieving substantial improvements. Likewise, there were statistically significant differences between measurements over time for the EG on S-OE (p < 0.001, Cohen´s d = 0.99); V-OE (p = 0.038, Cohen´s d = 0.27); V-CE (p = 0.006, Cohen´s d = 0.39), anteroposterior movements of CoP with Open-Eyes (RMSY-OE) (p = 0.038, Cohen´s d = 0.60) and activity of TrA under contraction conditions (p < 0.001, Cohen´s d = 0.53). Conclusions: The application of eight weeks of AHT leads to positive outcomes in posture control, as well as an improvement in the deep trunk muscle contraction in the female population.

An Evaluation of an Innovative Exercise to Relieve Chronic Low Back Pain in Sedentary Workers.

The purpose of the study was to examine the effectiveness of a novel supported dynamic lumbar extension with the abdominal drawing-in maneuver (ADIM) technique on stature change, deep abdominal muscle activity, trunk muscle fatigue, and pain intensity during prolonged sitting in chronic low back pain (CLBP) participants. Prolonged sitting can cause trunk muscle fatigue from continuous contraction of deep trunk muscles in seated postures. Deficiency of activity of deep muscles can reduce muscular support of the spine, causing stress on spinal structures, which could result in pain. Thirty participants with CLBP were randomly allocated: (a) control-sitting without exercise, and (b) intervention-supported dynamic lumbar extension with the ADIM technique. Compared to the intervention condition, the control condition demonstrated significantly greater deterioration in stature change, increased levels of deep trunk muscle fatigue, and an increase in pain during prolonged sitting. The supported dynamic lumbar extension with the ADIM technique appears to provide a protective effect on detrimental stature change and deep trunk muscle fatigue. In addition, it prevented an increase in pain intensity during prolonged sitting in people with CLBP. Sedentary behavior harms health, particularly affecting the lower back. Clinicians can use the intervention to induce dynamic lumbar movement, and this exercise can maintain deep trunk muscle activity during prolonged sitting, thereby helping to prevent low back pain (LBP) problems.

The immediate effect of the abdominal drawing-in maneuver technique on stature change in seated sedentary workers with chronic low back pain

Many studies have measured stature change arising from loads imposed on the spine during sitting. To improve stature recovery, it is important to stabilise the lumbar spine and compensate forces from the upper body. The abdominal drawing-in maneuver (ADIM) technique has been found to mainly activate deep trunk muscles. The purpose of this study was to determine whether activation of deep trunk muscles by the ADIM technique could immediately improve stature recovery during prolonged sitting. Twenty-four patients with chronic low back pain (CLBP) were randomly allocated into different orders of experimental conditions: control (sitting without ADIM technique) and intervention conditions (sitting with ADIM technique). The latter condition required participants to complete ADIM technique for 1 min and repeat it three times throughout 41 min prolonged sitting time. Stature recovery was improved by 3.292 mm in the intervention condition compared with control condition (p-value = 0.001). Our finding demonstrated that ADIM technique improved stature recovery. Practitioner Summary: Prolonged sitting seemingly harms sedentary workers’ health, particularly affecting the lower back. Activation of deep trunk muscles using abdominal drawing-in maneuver technique can promote spinal recovery. Clinicians can teach abdominal drawing-in maneuver technique to activate deep trunk muscles in chronic low back pain, thereby promoting self-management of seated stature recovery. Abbrevations: ADIM: abdominal drawing-in maneuver; RA: rectus abdominis; ICLT: iliocostalis lumborum pars thoracis; LM: lumbar multifidus; TrA: transversus abdominis; IO: internal oblique; CLBP: chronic low back pain; LBP: low back pain; RMDQ: Roland Morris disability questionnaire; NRS: numerical rating scale.