ABDOMINAL PRESSURIZATION AND MUSCLE ACTIVATION DURING SUPINE TRUNK CURLS

Trunk curls are common exercises in sports training. A multitude of practical recommendations exist on how to best perform this type of exercise to reach a specific effect. Since abdominal muscles can contribute to breathing, it was thought of interest to study the effects of systematic variations in breathing on the pattern of abdominal muscle activation during trunk curls. Of particular interest was the influence of fluctuations in the intra-abdominal pressure (IAP), since changes in IAP have been shown to be coupled to the activation of the innermost abdominal muscle, the Transversus abdominis (TrA), and also to be able to contribute to an extensor moment of the trunk

Effect of spinal manipulation on sensorimotor functions in back pain patients: study protocol for a randomised controlled trial

<p>Abstract</p> <p>Background</p> <p>Low back pain (LBP) is a recognized public health problem, impacting up to 80% of US adults at some point in their lives. Patients with LBP are utilizing integrative health care such as spinal manipulation (SM). SM is the therapeutic application of a load to specific body tissues or structures and can be divided into two broad categories: SM with a high-velocity low-amplitude load, or an impulse "thrust", (HVLA-SM) and SM with a low-velocity variable-amplitude load (LVVA-SM). There is evidence that sensorimotor function in people with LBP is altered. This study evaluates the sensorimotor function in the lumbopelvic region, as measured by postural sway, response to sudden load and repositioning accuracy, following SM to the lumbar and pelvic region when compared to a sham treatment.</p> <p>Methods/Design</p> <p>A total of 219 participants with acute, subacute or chronic low back pain are being recruited from the Quad Cities area located in Iowa and Illinois. They are allocated through a minimization algorithm in a 1:1:1 ratio to receive either 13 HVLA-SM treatments over 6 weeks, 13 LVVA-SM treatments over 6 weeks or 2 weeks of a sham treatment followed by 4 weeks of full spine "doctor's choice" SM. Sensorimotor function tests are performed before and immediately after treatment at baseline, week 2 and week 6. Self-report outcome assessments are also collected. The primary aims of this study are to 1) determine immediate pre to post changes in sensorimotor function as measured by postural sway following delivery of a single HVLA-SM or LVVA-SM treatment when compared to a sham treatment and 2) to determine changes from baseline to 2 weeks (4 treatments) of HVLA-SM or LVVA-SM compared to a sham treatment. Secondary aims include changes in response to sudden loads and lumbar repositioning accuracy at these endpoints, estimating sensorimotor function in the SM groups after 6 weeks of treatment, and exploring if changes in sensorimotor function are associated with changes in self-report outcome assessments.</p> <p>Discussion</p> <p>This study may provide clues to the sensorimotor mechanisms that explain observed functional deficits associated with LBP, as well as the mechanism of action of SM.</p> <p>Trial registration</p> <p>This trial is registered in ClinicalTrials.gov, with the ID number of <a href="http://www.clinicaltrials.gov/ct2/show/NCT00830596">NCT00830596</a>, registered on January 27, 2009. The first participant was allocated on 30 January 2009 and the final participant was allocated on 17 March 2011.</p

Movement Smoothness Metrics in Human-Machine Interaction

The evaluation of motion abilities is crucial to rate human movement control performance in several contexts. In the medical field, for example, smoothness, a feature related to the regularity of movement, is assessed through objective metrics during the execution of free movements in order to support the decision based on clinical scales about the impairment severity. Nevertheless, individuals with and without impairment interact daily with machines to improve their well-being in many contexts: rehabilitation, collaborative robotics, and sport exercises, among others. During these activities, they perform movements in a closed-chain, where inertial or resistance forces introduced by an external tool could affect their motion control. In this study, closed-chain movements performed by three able-bodied and five individuals with coordination impairments were investigated; three different smoothness metrics presented in the literature were applied to analyze the results. The experimental tests consisted in moving a slider mounted on a linear rail with varying velocity and resistance force conditions. Position in the main direction, accelerations and forces in all directions were recorded during the tests. All the metrics detected a smoothness improvement when velocity increased, while only two metrics found an influence of the resistance force on the smoothness

Overground walking with a robotic exoskeleton elicits trunk muscle activity in people with high-thoracic motor-complete spinal cord injury

Background: The trunk muscles are critical for postural control. Recent neurophysiological studies have revealed sparing of trunk muscle function in individuals with spinal cord injury (SCI) classified with thoracic or cervical motor-complete injuries. These findings raise the possibility for recruiting and retraining this spared trunk function through rehabilitation. Robotic gait training devices may provide a means to promote trunk muscle activation. Thus, the objective of this study was to characterize and compare the activation of the trunk muscles during walking with two robotic gait training devices (Ekso and Lokomat) in people with high thoracic motor-complete SCI. Methods: Participants with chronic motor-complete paraplegia performed 3 speed-matched walking conditions: Lokomat-assisted walking, Ekso-assisted walking overground, and Ekso-assisted walking on a treadmill. Surface electromyography (EMG) signals were recorded bilaterally from the rectus abdominis (RA), external oblique (EO), and erector spinae (ES) muscles. Results: Greater recruitment of trunk muscle EMG was elicited with Ekso-assisted walking compared to the Lokomat. Similar levels of trunk EMG activation were observed between Ekso overground and Ekso on the treadmill, indicating that differences between Ekso and Lokomat could not be attributed to the use of a hand-held gait aid. The level of trunk EMG activation during Lokomat walking was not different than that recorded during quiescent supine lying. Conclusions: Ekso-assisted walking elicits greater activation of trunk muscles compared to Lokomat-assisted walking, even after controlling for the use of hand-held assistive devices. The requirement of the Ekso for lateral weight-shifting in order to activate each step could lead to better postural muscle activation.Education, Faculty ofOther UBCKinesiology, School ofReviewedFacult