Complaints of musculoskeletal pain are common among employees who stand for prolonged periods. This study sought to determine if an anti-fatigue mat (AFM) could uniquely affect low back pain (LBP), low back posture, and foot-floor interface responses in individuals prone to developing LBP (termed pain developers (PDs)) during prolonged standing experiments compared to those who do not develop LBP under the same exposures (termed non pain developers (NPDs)). Sixteen volunteers (8 PDs and 8 NPDs) were recruited based on their pain-development tendencies, which were established in previous standing experiments.
View Article and Find Full Text PDFPotential alternatives for conventional sitting and standing postures are hybrid sit-stand postures (i.e. perching).
View Article and Find Full Text PDFUnlabelled: Recent work utilizing ultrasound imaging demonstrated that individuals with low back pain (LBP) have increased thickness and decreased mobility of the thoracolumbar fascia (TLF), an indication that the TLF may play a role in LBP. This study used a porcine injury model (microsurgically induced local injury)-shown to produce similar results to those observed in humans with LBP-to test the hypothesis that TLF mechanical properties may also be altered in patients with LBP. Perimuscular TLF tissue was harvested from the noninjured side of vertebral level L3-4 in pigs randomized into either control (n = 5) or injured (n = 5) groups.
View Article and Find Full Text PDFThis study investigated how task demands affect postural behaviour during standing. Twenty-four participants completed three different 12-min tasks: (1) a cognitive task that involved answering questions based on a written passage; (2) a light manual assembly task; and (3) standing quietly with no secondary task. The manual task was associated with the lowest amount of postural movement and a more static pose than the other two conditions.
View Article and Find Full Text PDFBackground: While stooping and crouching postures are critical for many activities of daily living, little is known about the balance control mechanisms employed during these postures. Accordingly, the purpose of this study was to characterize the mechanisms driving net center of pressure (COP) movement across three postures (standing, stooping, and crouching) and to investigate if control in each posture was influenced by time.
Methods: Ten young adults performed the three postures for 60s each.
While epidemiologic data suggests that one in four older adults have difficulty performing stooping and crouching (SC) tasks, little is known about how aging affects SC performance. This study investigated differences between young and older adults in lower limb kinematics and underfoot center of pressure (COP) measures when performing a series of SC tasks. Twelve healthy younger and twelve healthy older participants performed object-retrieval tasks varying in: (1) initial lift height, (2) precision demand, and (3) duration.
View Article and Find Full Text PDFBackground: Currently, it is unknown whether the inverted pendulum model is applicable to stooping or crouching postures. Therefore, the aim of this study was to determine the degree of applicability of the inverted pendulum model to these postures, via examination of the relationship between the centre of mass (COM) acceleration and centre of pressure (COP)-COM difference.
Methods: Ten young adults held static standing, stooping and crouching postures, each for 20s.
Safety floors (also known as compliant floors) may reduce the risk of fall-related injuries by attenuating impact force during falls, but are only practical if they do not negatively affect balance and mobility. In this study, we evaluated seven safety surfaces based on their ability to attenuate peak femoral neck force during simulated hip impacts, and their influence on center of pressure (COP) sway during quiet and tandem stance. Overall, we found that some safety floors can attenuate up to 33.
View Article and Find Full Text PDF'Safety floors' aim to decrease the risk of fall-related injuries by absorbing impact energy during falls. Ironically, excessive floor deflection during walking or standing may increase fall risk. In this study we used a materials testing system to characterize the ability of a range of floors to absorb energy during simulated head and hip impacts while resisting deflection during simulated single-leg stance.
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