Effect of modified bridge exercise on trunk muscle activity in healthy adults: a cross sectional study

Comparison of the Electromyography Activity during Exercises with Stable and Unstable Surfaces: A Systematic Review and Meta-Analysis

The effect of electromyographic (EMG) activity on agonist muscles during exercises performed on stable and unstable surfaces remains uncertain. We aimed to review the literature regarding the comparison of the EMG activity of the agonist muscles of exercises performed on stable and unstable surfaces. Eighty-six studies that evaluated the EMG activity of 1783 individuals during exercises for the lower limbs, upper limbs, and core were included. The EMG activities of the pectoralis major (SMD = 0.28 [95% CI 0.09, 0.47]) and triceps brachii muscles (SMD = 0.45 [95% CI 0.25, 0.66]) were significantly increased when the unstable device was added to the exercise. Likewise, the EMG activity of all core muscles showed a significant increase with the unstable surface during the exercises, such as the rectus abdominis (SMD = 0.51 [95% CI 0.37, 0.66]), external oblique (SMD = 0.44 [95% CI 0.28, 0.61]), internal oblique (SMD = 1.04 [95% CI 0.02, 2.07]), erector spinae (SMD = 0.37 [95% CI 0.04, 0.71]), and lumbar multifidus (SMD = 0.35 [95% CI 0.08, 0.61]). However, the lower limb muscles did not show greater EMG activity during the exercise with unstable surfaces compared to the stable surface. In conclusion, unstable conditions increase the EMG activity of some upper limb and core muscles compared to a stable surface.

Ipsilateral versus contralateral static endurance- balance abilities among healthy college students

Objectives

This study sought to determine the association and the difference, if any, between the levels of the contralateral and between the levels of the ipsilateral sides during static endurance-balance exercise.

Methods

One hundred twelve healthy active- college students (55 females and 57 males) participated in this cross-sectional study. Each participant performed the contralateral (raising one arm and opposite-side leg) quadruped bird dog exercise and balanced in static condition. Side bridge exercise was performed from lying on your side then engaging your core muscles and lifting your upper body and hips off the ground, maintaining a straight line and holding this position as long as tolerated.

Results

Wilcoxon signed rank test showed significant difference (p = 0.004) between the contralateral right and left quadruped bird dog but insignificant difference (p = 0.059) between the ipsilateral right and left side bridge endurance-balance exercises. Mann-Whitney U test showed that the holding time was significant across gender for the contralateral but was insignificant for the ipsilateral endurance-balance exercise. Mann-Whitney U test was insignificant (p > 0.05) between those being recreationally active or inactive. Kruskal-Wallis test revealed insignificant difference between body mass index categories. Spearman's rho correlation coefficient showed strong positive correlation equals 0.85 and 0.75 (p < 0.001) of the contralateral quadruped bird dog and the ipsilateral side bridge exercises respectively.

Conclusions

A significant difference was observed for contralateral, while no significant difference was found for ipsilateral endurance-balance abilities. Therefore, clinicians and rehab specialist should consider these findings when assessing the endurance-balance abilities to properly devise appropriate exercise progression of different trunk stabilizers.

Task-Based Functional Connectivity and Blood-Oxygen-Level-Dependent Activation During Within-Scanner Performance of Lumbopelvic Motor Tasks: A Functional Magnetic Resonance Imaging Study

There are a limited number of neuroimaging investigations into motor control of the lumbopelvic musculature. Most investigation examining motor control of the lumbopelvic musculature utilize transcranial magnetic stimulation (TMS) and focus primarily on the motor cortex. This has resulted in a dearth of knowledge as it relates to how other regions of the brain activate during lumbopelvic movement. Additionally, task-based functional connectivity during lumbopelvic movements has not been well elucidated. Therefore, we used functional magnetic resonance imaging (fMRI) to examine brain activation and ROI-to-ROI task-based functional connectivity in 19 healthy individuals (12 female, age 29.8 ± 4.5 years) during the performance of three lumbopelvic movements: modified bilateral bridge, left unilateral bridge, and right unilateral bridge. The whole brain analysis found robust, bilateral activation within the motor regions of the brain during the bilateral bridge task, and contralateral activation of the motor regions during unilateral bridging tasks. Furthermore, the ROI-to-ROI analysis demonstrated significant connectivity of a motor network that included the supplemental motor area, bilateral precentral gyrus, and bilateral cerebellum regardless of the motor task performed. These data suggest that while whole brain activation reveals unique patterns of activation across the three tasks, functional connectivity is very similar. As motor control of the lumbopelvic area is of high interest to those studying low back pain (LBP), this study can provide a comparison for future research into potential connectivity changes that occur in individuals with LBP.

Evoking the Withdrawal Reflex via Successive Needle-Pricking on the Plantar and Dorsal Aspect of the Foot Increases the FMA of the Lower Limb for Poststroke Patients in Brunnstrom Stage III: A Preliminary Study

The withdrawal reflex is a defensive reaction to nociceptive stimuli and can be used to regulate locomotor gait during rehabilitation. We investigated the effect of successive needle-pricking of the plantar and dorsal foot surfaces on poststroke lower limb function. Thirty-five hemiplegic patients, within one month after primary stroke, with an affected lower limb (Brunnstrom stage III) were randomly divided into intervention and control groups. Both groups received routine drug treatment, rehabilitation training, and upper limb acupuncture treatment on the hemiplegic side. The control group also received routine acupuncture on the hemiplegic side of the lower limb, while the intervention group received successive needle-pricking on the sole and instep of both the unaffected and affected side feet. Outcomes were assessed before inception (D0) and after three (D3) and six (D6) treatment days, using Brunnstrom stage (Ueda assessment), total Fugl–Meyer lower extremity assessment (FMA-LE) and its subscores (FMA-LE-ss), active lower limb range of motion (AROM-LL), Modified Ashworth Scale Score (MAS-LL), and manual muscle testing (MMT-LL). The Brunnstrom stage was better in the intervention group than in the control group at both D3 and D6 (P < 0.01). The total FMA-LE score and sections B, C, D, and G FMA-LE-ss were significantly better in the intervention group than in the control group at D3 and D6 (P < 0.05). The AROM-LL hip and knee flexion and hip extension improved more in the intervention group than in the control group (P < 0.05). In the intervention group, MAS-LL hip flexion significantly improved at D6 (P < 0.01). Improvement in lower limb joints on the MMT-LL in the intervention group exceeded that in the control group at D6 (P < 0.01). Successive needle-pricking on the plantar and dorsal foot aspects of Brunnstrom stage III in poststroke patients contributed to rapid lower limb motor function improvement via the withdrawal reflex. This trial is registered with ChiCTR1900020633.

Assessing sensorimotor control of the lumbopelvic-hip region using task-based functional MRI

Recent brain imaging studies have suggested that cortical remodeling within sensorimotor regions are associated with persistent low back pain and may be a driving mechanism for the impaired neuromuscular control associated with this condition. This paper outlines a new approach for investigating cortical sensorimotor integration during the performance of small-amplitude lumbopelvic movements with functional MRI. Fourteen healthy right-handed participants were instructed in the lumbopelvic movement tasks performed during fMRI acquisition. Surface electromyography (EMG) collected on 8 lumbopelvic and thigh muscles captured organized patterns of muscle activation during the movement tasks. fMRI data were collected on 10 of 14 participants. Sensorimotor cortical activation across the tasks was identified using a whole brain analysis and further explored with regional analyses of key components of the cortical sensorimotor network. Head motion had low correlation to the tasks (r = -0.101 to 0.004) and head translation averaged 0.98 (0.59 mm) before motion correction. Patterns of activation of the key lumbopelvic and thigh musculature (average amplitude normalized 2-17%) were significantly different across tasks (P > 0.001). Neuroimaging demonstrated activation in key sensorimotor cortical regions that were consistent with motor planning and sensory feedback needed for performing the different tasks. This approach captures the specificity of lumbopelvic sensorimotor control using goal-based tasks (e.g., "lift your hip" vs. "contract your lumbar multifidus to 20% of maximum") performed within the confines of the scanner. Specific patterns of sensorimotor cortex activation appear to capture differences between bilateral and unilateral tasks during voluntary control of multisegmental movement in the lumbopelvic region.NEW & NOTEWORTHY We demonstrated the feasibility of using task-based functional magnetic resonance imaging (fMRI) protocols for acquiring the blood oxygen level-dependent (BOLD) response of key sensorimotor cortex regions during voluntary lumbopelvic movements. Our approach activated lumbopelvic muscles during small-amplitude movements while participants were lying supine in the scanner. Our data supports these tasks can be done with limited head motion and low correlation of head motion to the task. The approach provides opportunities for assessing the role of brain changes in persistent low back pain.

Does trunk and hip muscles strength predict performance during a core stability test?

BACKGROUND

A better understanding about the relationship between trunk and hip muscles strength and core stability may improve evaluation and interventions proposed to improve core stability.

OBJECTIVES

To investigate if trunk and hip muscles strength predict pelvic posterior rotation during the bridge test with unilateral knee extension.

METHODS

This is a cross-sectional study. Sixty-one healthy individuals of both sexes (age, 28±6.4 years, weight, 66.5±10.9kg, height, 167±9.5cm) performed the bridge test with unilateral knee extension. The pelvic posterior rotation during the bridge test was obtained with two-dimensional video analysis. Isometric strength of the trunk extensors and rotators, and hip abductors, external and internal rotators and extensors were measured with a hand-held dynamometer. Multiple linear regression analysis was performed to identify if the strength variables could explain the pelvic posterior rotation during the test.

RESULTS

Muscle strength predicted pelvic posterior rotation during the bridge test (r=0.54; p=0.003). Strength of the trunk rotators (p=0.045) and hip internal rotators (p=0.015) predicted reduced magnitude of pelvic posterior rotation during the bridge test, and strength of the hip extensors (p=0.003) predicted increased magnitude of pelvic posterior rotation.

CONCLUSIONS

Trunk rotators and hip internal rotators and extensors strength predict 29% of the performance during the bridge test with unilateral knee extension. The strength of these muscles should be evaluated in individuals with increased pelvic posterior rotation during the bridge test with unilateral knee extension.