Control Of Muscle Activity Research Articles

Influencing factors of corticomuscular coherence in stroke patients.

Stroke, also known as cerebrovascular accident, is an acute cerebrovascular disease with a high incidence, disability rate, and mortality. It can disrupt the interaction between the cerebral cortex and external muscles. Corticomuscular coherence (CMC) is a common and useful method for studying how the cerebral cortex controls muscle activity. CMC can expose functional connections between the cortex and muscle, reflecting the information flow in the motor system. Afferent feedback related to CMC can reveal these functional connections. This paper aims to investigate the factors influencing CMC in stroke patients and provide a comprehensive summary and analysis of the current research in this area. This paper begins by discussing the impact of stroke and the significance of CMC in stroke patients. It then proceeds to elaborate on the mechanism of CMC and its defining formula. Next, the impacts of various factors on CMC in stroke patients were discussed individually. Lastly, this paper addresses current challenges and future prospects for CMC.

The relationship between balance control and thigh muscle strength and muscle activity in persons with incomplete spinal cord injury

Study designCross-sectional study.ObjectivesA spinal cord injury (SCI) can compromise the ability to maintain sufficient balance control during activities in an upraised position. The objective of the study was to explore the relationship between balance control and muscle strength and muscle activation in the lower extremities in persons with incomplete SCI (iSCI).SettingSunnaas Rehabilitation Hospital, Norway.MethodsThirteen men and two women with iSCI and 15 healthy, matched controls were included. Performance of the Berg Balance Scale (BBS) short version (7 items) was used to indicate balance control. Maximal voluntary contraction (MVC) was performed to measure isometric muscle strength in thigh muscles (knee extension/flexion), while surface electromyography (EMG) was measured from M. Vastus Lateralis and M. Biceps Femoris. The relative activation of each muscle during each of the BBS tasks was reported as the percentage of the maximal activation during the MVC (%EMGmax).ResultsThe iSCI participants had a significantly lower BBS sum score and up to 40% lower muscle strength in knee- flexion and extension compared to the matched healthy controls. They also exhibited a significantly higher %EMGmax, i.e. a higher muscle activation, during most of the balance tests. Univariate regression analysis revealed a significant association between balance control and mean values of %EMGmax in Biceps Femoris, averaged over the seven BBS tests.ConclusionsThe participants with iSCI had poorer balance control, reduced thigh muscle strength and a higher relative muscle activation in their thigh muscles, during balance-demanding activities.

Timing and precision of rattlesnake spinal motoneurons are determined by the KV72/3 potassium channel

The evolution of novel motor behaviors requires modifications in the central pattern generators (CPGs) controlling muscle activity. How such changes gradually lead to novel behaviors remains enigmatic due to the long time course of evolution. Rattlesnakes provide a unique opportunity to investigate how a locomotor CPG was evolutionarily modified to generate a novel behavior-in this case, acoustic signaling. We show that motoneurons (MNs) in the body and tail spinal cord of rattlesnakes possess fundamentally different physiological characteristics, which allow MNs in the tail to integrate and transmit CPG output for controlling superfast muscles with high temporal precision. Using patch-clamp electrophysiology, we demonstrate that these differences in locomotor and rattle MNs are mainly determined by KV72/3 potassium channels. However, although KV72/3 exerted a significantly different influence on locomotor and rattle MN physiology, single-cell RNA-seq unexpectedly did not reveal any differences in KV72/3 channels' expression. VIDEO ABSTRACT.

바드라가즈 링 기법이 만성 뇌졸중 환자의 몸통 조절과 다리 근육의 근활성도에 미치는 효과

바드라가즈 링 기법이 만성 뇌졸중 환자의 몸통 조절과 다리 근육의 근활성도에 미치는 효과

The imbalance of body electrolytes in HIV patients using highly active antiretroviral therapy

The retrovirus named HIV (Human Immunodeficiency Virus) targets the immune system, which makes it more vulnerable to numerous illnesses and some cancers that healthy immune systems can combat. The worst phase of HIV infection, AIDS (Acquired Immunodeficiency Syndrome), can take a variety of people between one and twenty years to emerge if untreated. HIV is frequently spread by unprotected sexual contact, blood transfusions, mother-to-child transmission, etc. HIV/AIDS symptoms include weight loss, skin problems, achy muscles, recurrent fevers. Prevention of HIV/AIDS includes use of condom, avoidance of exposure to implicated body fluids, HIV prevention programs to stop vertical HIV transmission. Highly active antiretroviral therapy (HAART), which reduces the disease's progression, is the main form of treatment. The HAART's effect on the kidney results in electrolytes imbalance. Electrolytes are substances that, when dissolved in water, transmit electricity and control blood pressure, pH level, neuron and muscle activity, and maintain tissues hydrated. Irregularity in the body's electrolyte content is known as an electrolyte imbalance which can be caused by fluid lose, inadequate water consumption, certain medications. Symptoms of electrolyte imbalances include, irregular heartbeat, fatigue, headaches, confusion, numbness and tingling. Diagnosis of Electrolyte Imbalance in HIV/AIDS Patients are done using kidney function test, pinch test and electrocardiogram. Treatment and management of electrolytes imbalance in HIV/AIDS patients include drinking water, oral rehydration drinks, sodium chloride, intravenous fluids, oral medications and supplements such as gluconate, magnesium oxide, use of dialysis. HAART induced electrolytes imbalance are seen in Tenofovir, which is associated with severe hypokalemia and hypophosphatemia.

Predicting underlying pathology in simulated cardiac muscle twitches

Muscle cells contain a highly organized and complexly regulated filament lattice with repetitive structure, where both inter- and intra-filament interactions control muscle activation and relaxation. Genetic cardiomyopathies, such as hypertrophic cardiomyopathy (HCM), can arise from dysfunction in any of the major components of muscle (thin, thick and titin filaments). We hypothesize that cellular scale (twitch) metrics contain enough information to predict specific protein perturbations, and lend insights into targeted compensatory interventions.

Effect of Suboptimal Neuromuscular Control on the Risk of Massive Wear in Total Knee Replacement

The optimal neuromuscular control (muscle activation strategy that minimises the consumption of metabolic energy) during level walking is very close to that which minimises the force transmitted through the joints of the lower limbs. Thus, any suboptimal control involves an overloading of the joints. Some total knee replacement patients adopt suboptimal control strategies during level walking; this is particularly true for patients with co-morbidities that cause neuromotor control degeneration, such as Parkinson’s Disease (PD). The increase of joint loading increases the risk of implant failure, as reported in one study in PD patients (5.44% of failures at 9 years follow-up). One failure mode that is directly affected by joint loading is massive wear of the prosthetic articular surface. In this study we used a validated patient-specific biomechanical model to estimate how a severely suboptimal control could increase the wear rate of total knee replacements. Whereas autopsy-retrieved implants from non-PD patients typically show average polyethylene wear of 17 mm3 per year, our simulations suggested that a severely suboptimal control could cause a wear rate as high as of 69 mm3 per year. Assuming the risk of implant failure due to massive wear increase linearly with the wear rate, a severely suboptimal control could increase the risk associated to that failure mode from 0.1% to 0.5%. Based on these results, such increase would not be not sufficient to justify alone the higher incidence rate of revision in patients affected by Parkinson’s Disease, suggesting that other failure modes may be involved.

Motoneuron-specific loss of VAChT mimics neuromuscular defects seen in congenital myasthenic syndrome.

Motoneurons (MNs) control muscle activity by releasing the neurotransmitter acetylcholine (ACh) at the level of neuromuscular junctions. ACh is packaged into synaptic vesicles by the vesicular ACh transporter (VAChT), and disruptions in its release can impair muscle contraction, as seen in congenital myasthenic syndromes (CMS). Recently, VAChT gene mutations were identified in humans displaying varying degrees of myasthenia. Moreover, mice with a global deficiency in VAChT expression display several characteristics of CMS. Despite these findings, little is known about how a long-term decrease in VAChT expression invivo affects MNs structure and function. Using Cre-loxP technology, we generated a mouse model where VAChT is deleted in select groups of MNs (mnVAChT-KD). Molecular analysis revealed that the VAChT deletion was specific to MNs and affected approximately 50% of its population in the brainstem and spinal cord, with alpha-MNs primarily targeted (70% in spinal cord). Within each animal, the cell body area of VAChT-deleted MNs was significantly smaller compared to MNs with VAChT preserved. Likewise, muscles innervated by VAChT-deleted MNs showed atrophy while muscles innervated by VAChT-containing neurons appeared normal. In addition, mnVAChT KD mice had decreased muscle strength, were hypoactive, leaner and exhibited kyphosis. This neuromuscular dysfunction was evident at 2months of age and became progressively worse by 6months. Treatment of mutants with a cholinesterase inhibitor was able to improve some of the motor deficits. As these observations mimic what is seen in CMS, this new line could be valuable for assessing the efficacy of potential CMS drugs.

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.

Single-cell transcriptomic analysis of the adult mouse spinal cord reveals molecular diversity of autonomic and skeletal motor neurons.

The spinal cord is a fascinating structure responsible for coordinating movement in vertebrates. Spinal motor neurons control muscle activity by transmitting signals from the spinal cord to diverse peripheral targets. We profiled 43,890 single-nucleus transcriptomes from the adult mouse spinal cord using fluorescence-activated nuclei sorting to enrich for motor neuron nuclei. We identified 16 sympathetic motor neuron clusters, which are distinguishable by spatial localization and expression of neuromodulatory signaling genes. We found surprising skeletal motor neuron heterogeneity in the adult spinal cord, including transcriptional differences that correlate with electrophysiologically and spatially distinct motor pools. We also provide evidence for a novel transcriptional subpopulation of skeletal motor neuron (γ*). Collectively, these data provide a single-cell transcriptional atlas (http://spinalcordatlas.org) for investigating the organizing molecular logic of adult motor neuron diversity, as well as the cellular and molecular basis of motor neuron function in health and disease.

Simulating Cardiac Muscle Mutations in a Compliant Lattice with Commonly Used Assays

Cardiac muscle cells consist of a highly organized filament lattice with repetitive structure. Both inter- and intra-filament interactions control muscle activation and relaxation, and even small perturbations of these interactions can result in the development of cardiomyopathies. Building on an existing spatially explicit computational model of muscle contraction at the half-sarcomere level, we simulated different mutations by changing model parameters using published biochemical or biomechanical data. Importantly, we added the ability to specify profiles of protein properties and their frequency (penetrance) within the model. We assigned the mutant properties to a portion of the proteins, with the remainder retaining wildtype properties. The current model consists of 8 thin filaments, with a four state cardiac troponin-tropomyosin regulation cycle, determining accessibility of actin binding sites for myosin motor heads arising from the 4 thick filaments. Upon binding, the myosin motors follow a three-state model of the crossbridge cycle to generate axial tension. We simulated the cardiac troponin c (cTnC) mutation L48Q, which has increased calcium binding affinity, and the non-functional cTnC mutation D65A, which prevents calcium from binding at site II (contraction trigger site). Additionally, we co-varied cross-bridge cycle transition rates, increasing the attachment rate and decreasing the detachment rates to simulate the effect of myosin mutations, to study how this affected contraction with different dosages of L48Q. We simulated isometric twitch force, the force-pCa relationship, and filament material properties assays. For the isometric twitches, we specified a calcium transient derived from published intra-lattice measurements. Our results show emergent contractile dynamics similar to the respective experimental phenotypes. L48Q, with increasing penetrance, increases calcium sensitivity and linearly increases maximum tension, as well as time at maximum tension. D65A decreases maximum tension, and our myosin treatment increases maximum tension, and slows relaxation.

The effect of hyper-pronated foot on postural control and ankle muscle activity during running and cutting movement

Objective: The aim of this study was to examine the effect of hyper pronated foot on postural control and ankle muscle activity during running and cutting movement (v-cut).&#x0D; Methods: In this Cross-Sectional study, 42 young physically active (exercising three times per week regularly) males participated in this study, including 21 with hyper-pronated feet and 21 with normal feet. Each participant completed a running and cutting task. Body postural control was measured using a force platform (1000Hz) which was synchronized with surface electromyography of selected ankle muscles. MATLAB software was used to process and analyze the data. One-away ANOVA was used to identify any differences between groups.&#x0D; Results: Differing muscle activation patterns in the surrounding ankle musculature (tibialis anterior, peroneus longus) through to reduced postural stability in the medial-lateral direction and increased vertical ground reaction forces were observed between groups.&#x0D; Conclusion: According to the obtained results it seems that subtalar hyper-pronation can be regarded as a factor affecting the biomechanics of cutting by changing activation patterns of the muscles surrounding the ankle, and reducing postural control of the body in medial-lateral direction, but not in anterior-posterior direction.

Evaluating Postural Control and Lower-extremity Muscle Activation in Individuals with Chronic Ankle Instability.

Computerized dynamic posturography (CDP) is an objective technique for the evaluation of postural stability under static and dynamic conditions and perturbation. CDP is based on the inverted pendulum model that traces the interrelationship between the center of pressure and the center of gravity. CDP can be used to analyze the proportions of vision, proprioception, and vestibular sensation to maintain postural stability. The following characters define chronic ankle instability (CAI): persistent ankle pain, swelling, the feeling of "giving way," and self-reported disability. Postural stability and fibular muscle activation level in individuals with CAI decreased due to lateral ankle ligament complex injuries. Few studies have used CDP to explore the postural stability of individuals with CAI. Studies that investigate postural stability and related muscle activation by using synchronized CDP with surface electromyography are lacking. This CDP protocol includes a sensory organization test (SOT), a motor control test (MCT), and an adaption test (ADT), as well as tests that measure unilateral stance (US) and limit of stability (LOS). The surface electromyography system is synchronized with CDP to collect data on lower limb muscle activation during measurement. This protocol presents a novel approach for evaluating the coordination of the visual, somatosensory, and vestibular systems and related muscle activation to maintain postural stability. Moreover, it provides new insights into the neuromuscular control of individuals with CAI when coping with real complex environments.

Evaluating Postural Control and Lower-extremity Muscle Activation in Individuals with Chronic Ankle Instability

Evaluating Postural Control and Lower-extremity Muscle Activation in Individuals with Chronic Ankle Instability

Role of cutaneous and proprioceptive inputs in sensorimotor integration and plasticity occurring in the facial primary motor cortex

Previous studies investigating the effects of somatosensory afferent inputs on cortical excitability and neural plasticity often used transcranial magnetic stimulation (TMS) of hand motor cortex (M1) as a model, but in this model it is difficult to separate out the relative contribution of cutaneous and muscle afferent input to each effect. In the face, cutaneous and muscle afferents are segregated in the trigeminal and facial nerves, respectively. We studied their relative contribution to corticobulbar excitability and neural plasticity in the depressor anguli oris M1. Stimulation of trigeminal afferents induced short-latency (SAI) but not long-latency (LAI) afferent inhibition of face M1, while facial nerve stimulation evoked LAI but not SAI. Plasticity induction was observed only after a paired associative stimulation protocol using the facial nerve. Physiological differences in effects of cutaneous and muscle afferent inputs on face M1 excitability suggest they play separate functional roles in behaviour. The lack of conventional muscle spindles in face muscles raises the question of how sensory input from the face is used to control muscle activation. In 16 healthy volunteers, we probed sensorimotor interactions in face motor cortex (fM1) using short-afferent inhibition (SAI), long-afferent inhibition (LAI) and LTP-like plasticity following paired associative stimulation (PAS) in the depressor anguli oris muscle (DAO). Stimulation of low threshold afferents in the trigeminal nerve produced a clear SAI (P<0.05) when the interval between trigeminal stimulation and transcranial magnetic stimulation (TMS) of fM1 was 15-30ms. However, there was no evidence for LAI at longer intervals of 100-200ms, nor was there any effect of PAS. In contrast, facial nerve stimulation produced significant LAI (P<0.05) as well as significant facilitation 10-30 minutes after PAS (P<0.05). Given that the facial nerve is a pure motor nerve, we presume that the afferent fibres responsible were those activated by the evoked muscle twitch. The F-wave in DAO was unaffected during both LAI and SAI, consistent with their presumed cortical origin. We hypothesize that, in fM1, SAI is evoked by activity in low threshold, presumably cutaneous afferents, whereas LAI and PAS require activity in (higher threshold) afferents activated by the muscle twitch evoked by electrical stimulation of the facial nerve. Cutaneous inputs may exert a paucisynaptic inhibitory effect on fM1, while proprioceptive information is likely to target inhibitory and excitatory polysynaptic circuits involved in LAI and PAS. Such information may be relevant to the physiopathology of several disorders involving the cranio-facial system.

Ultrasound Imaging of the Gluteal Muscles During the Y-Balance Test in Individuals With or Without Chronic Ankle Instability.

Impairments in dynamic postural control and gluteal muscle activation have been associated with the development of symptoms related to long-term injury, which are characteristic of chronic ankle instability (CAI). Ultrasound imaging (USI) provides a visual means to explore muscle thickness throughout movement; however, USI functional-activation ratios (FARs) of the gluteal muscles during dynamic balance exercises have not been investigated. To determine differences in gluteus maximus and gluteus medius FARs using USI, Y-Balance Test (YBT) performance, and lower extremity kinematics in individuals with or without CAI. Cross-sectional study. University laboratory. Twenty adults with CAI (10 men, 10 women; age = 21.70 ± 2.32 years, height = 172.74 ± 11.28 cm, mass = 74.26 ± 15.24 kg) and 20 adults without CAI (10 men, 10 women; age = 21.20 ± 2.79 years, height = 173.18 ± 15.16 cm, mass = 70.89 ± 12.18 kg). Unilateral static ultrasound images of the gluteal muscles during quiet stance and to the point of maximum YBT reach directions were obtained over 3 trials. Hip, knee, and ankle sagittal-plane kinematics were collected with motion-capture software. Gluteal thickness was normalized to quiet stance to yield FARs for each muscle in each YBT direction. We averaged normalized reach distances and obtained average peak kinematics. Independent t tests, mean differences, and Cohen d effect sizes were calculated to determine group differences for all outcome measures. The CAI group had anterior-reach deficits compared with the control group (mean difference = 4.37%, Cohen d = 0.77, P = .02). The CAI group demonstrated greater anterior gluteus maximus FARs than the control group (mean difference = 0.08, Cohen d = 0.57, P = .05). The CAI group demonstrated YBT reach deficits and alterations in proximal muscle activation. Increased reliance on the gluteus maximus during dynamic conditions may contribute to distal joint dysfunction in this population.

The Effect of Trunk Stability Exercise on Respiratory Muscles Function in Stroke Patients

Purpose : The purpose of this study is to examine the effects of trunk stability training on improving trunk control, respiratory function, and respiratory muscle activation in stroke patients. Methods : The subjects were assigned to two groups: the intervention group (n=15) and the control group (n=15). Both groups participated in a conventional stroke rehabilitation program, but the intervention group also received trunk stability training for 30 minutes a day, 3 times a week, for 6 weeks. The main trunk stability exercise consisted of the dead bug exercise. Trunk control was assessed using a trunk impairment scale, and respiratory function (pulmonary function and respiratory muscle function) was assessed using spirometry. The data were analyzed using the Pearson correlation, independent t-test, and paired t-test. Results : Trunk control was significantly positively correlated with pulmonary function and respiratory muscle strength. Both groups showed a significant increase in trunk control and respiratory function. Conclusion : This study demonstrated that a conventional stroke rehabilitation program and trunk stability training have positive effects on respiratory function and respiratory muscle activation in stroke patients.

Architecture of the nervous system in metacercariae of Diplostomum pseudospathaceum Niewiadomska, 1984 (Digenea).

The development of metacercariae of Diplostomum pseudospathaceum Niewiadomska, 1984 is accompanied by profound morphological transformations often characterized as metamorphosis, which makes these metacercariae an interesting case for studying the morphogenesis of the digenean nervous system. Although the nervous system of D. pseudospathaceum is one of the most extensively studied among digeneans, there are still gaps in our knowledge regarding the distribution patterns of some neuroactive substances, most notably neuropeptides. The present study addresses these gaps by studying pre-infective metacercariae of D. pseudospathaceum using immunochemical staining and confocal microscopy to characterize the distribution patterns of serotonin (5-HT) and two major groups of flatworm neuropeptides, FMRFamide-related (FaRPs) and substance P-related (SP) peptides. The general morphology of the nervous system was examined with antibodies to alpha-tubulin. The nervous system of the metacercariae was shown to conform to the most common morphology of the nervous system in the hermaphroditic generation, with three pairs of posterior nerve cords and four pairs of anterior nerves. The patterns of FaRP- and 5-HT immunoreactivity (IR) were similar to those revealed in earlier studies by cholinesterase activity, which is in accordance with the known role of these neurotransmitters in controlling muscle activity in flatworms. The SP-IR nervous system was significantly different and consisted of mostly bipolar cells presumably acting as mechanoreceptors. The architecture of the nervous system in D. pseudospathaceum metacercariae is discussed in comparison to that in cercariae of D. pseudospathaceum and metacercariae of related digenean species.

Forward head posture (FHP) angle and plantar pressure resulting from oscillatory stimulation training of the shoulder joint: A randomized controlled trial.

Oscillatory stimulation provides strong sensory stimulation, which can activate muscle spindles, strengthening proprioceptive sense and, therefore, helping to strengthen the muscles involved in posture stability. This study aimed to investigate the difference in average distribution of plantar pressure resulting from changes in the forward head position (FHP) angle caused by controlling muscle activity in the neck and shoulders through Bodyblade. The subjects were divided into an experimental group (Bodyblade, n= 15) and a control group (general physiotherapy, n= 15). Eighteen sessions of exercise were implemented. Craniovertebral angle (CVA) and cranial rotation angle (CRA) were measured to evaluate the change of FHP. The Gaitview AFA-50 (Alfoots Co, Korea) was used to measure the plantar pressure distribution. The experimental group showed a larger increase in CVA than the control group (p< 0.05). Only the experimental group showed a significant decrease in CRA (p< 0.05).Both the anterior pressure and posterior pressure showed a significant improvement only in the experimental group (p< 0.05). The experimental group showed a larger increase in anterior/posterior ratio than the control group (p< 0.05). Bodyblade improves the angle of FHP, thus positively affecting the average ratio of plantar pressure.

The effects of a moving environment on postural control and task performance during manual materials handling, visual tracking and arithmetic tasks

The purpose of this study was to evaluate the performance of cognitive tasks and manual materials handling in a moving environment. Specifically, we were interested in how task performance, postural control and lower limb muscle activation changed when tasks were performed in motion compared to no motion conditions. The motion trials were performed on a MOOG 2000E that created a 5-degree of freedom simulated environment. The tasks examined were a lifting task, a mental arithmetic task and a visual tracking task. Results of this experiment indicated that two outcome measures of a visual tracking task (time to task completion and performance errors) were negatively affected by motion, while arithmetic task performance was unaffected. Additionally, postural control was not affected by the presence of motion in the two cognitive tasks. Lifting was the only task where postural control appeared to be negatively affected as participants exhibited significant increases in lower limb muscle activation and non-significant increases in number of steps taken. The significant increase in time to completion and errors suggest that workers performing visual tracking type tasks in an offshore environment may be more prone to committing human factors errors. Furthermore, the results suggest that the risk of falls and injury due to loss of balance may be highest in workers regularly performing lifting tasks as this was the only instance where task performance in a moving environment negatively impacted postural control. These findings were attributed to greater demands placed on the postural control system when lifting during the motion condition. This study provides ergonomists with a resource they can use to better appreciate the risks associated with performance of job related tasks in a moving environment.