Leaning Position Research Articles

The influence of forward leaning postures on passenger injury in urban rail train collision

The influence of forward leaning postures on passenger injury in urban rail train collision

The Balance N1 Is Larger in Children With Anxiety and Associated With the Error-Related Negativity

BackgroundThe error-related negativity (ERN) is a brain response evoked by mistakes in cognitive tasks that is enhanced with anxiety and can predict the subsequent onset or exacerbation of anxiety in children and adolescents. A physical disturbance to standing balance evokes a brain response called the balance N1 that resembles the ERN in scalp topography and in response to a variety of moderating factors. We recently found that the balance N1 and ERN correlate in amplitude across small samples of adults. MethodsIn the current study, we tested the effect of anxiety on the balance N1 in children (ages 9–12 years) with and without diagnosed anxiety disorders (38 children with generalized anxiety, social anxiety, and/or obsessive-compulsive disorder and 50 children without these disorders). We measured the balance N1 in response to sudden release of support from a forward leaning posture, the ERN in response to mistakes on a Go/NoGo task, and anxiety symptoms using child- and parent-report forms of the Screen for Child Anxiety and Related Emotional Disorders. ResultsBoth the balance N1 and the ERN were larger in the anxious group. The balance N1 was also associated with both the ERN and parent report of child anxiety symptom severity across individuals. ConclusionsThe higher measurement reliability of the balance N1 than the ERN and greater experimental control over errors suggest that balance paradigms may provide a more powerful method for investigating individual differences in error-related brain activity related to anxiety.

Effect of Forward Trunk Lean Position with Pursed-lip Breathing on Pulmonary Ventilation and Heart Rate during Post-exercise Recovery in Obese Females

Effect of Forward Trunk Lean Position with Pursed-lip Breathing on Pulmonary Ventilation and Heart Rate during Post-exercise Recovery in Obese Females

Bow and Lean Test for Rare Variants of Vertical Semicircular Canal BPPV.

The objective of this study was to assess the clinical significance of the Bow and Lean Test (BLT) for the diagnosis of different variants of vertical canal Benign Paroxysmal Positional Vertigo (BPPV). BLT is commonly used for diagnoses of lateral semicircular canal (LSC) BPPV. However, vertical nystagmus in the BLT may indicate the presence of other variants such as PSC-BPPV. 567 patients with vertical canal BPPV were recruited. Patients with anterior semicircular canal (ASC) or PSC-BPPV were weekly examined until the negativization of BPPV. Nystagmus characteristics during BLT were analyzed. Of 567 patients with vertical canal BPPV, 1.4% had ASC-BPPV. BLT was positive in 155 patients, showing patterns like down-beating nystagmus in bowing and no nystagmus in leaning (15.52% of patients), and down-beating in bowing and up-beating in leaning (6.17%), which was predominantly present in PSC-canalolithiasis. Statistically significant differences were observed in the direction of nystagmus provoked by BLT in PSC-BPPV subtypes. No significant differences were found in nystagmus latency or duration during BLT positions. Among BPPV subtypes, there was a significant difference in nystagmus duration and latency, especially between cupulolithiasis and other variants. BLT's sensitivity was 0.93 in bowing and 1 in a leaning position, while specificity was 0.93 and 0.82 respectively. Beyond the LSC, the BLT has expanded to other variants. However, study results differ likely due to variations in patient characteristics and test execution. Currently, no specific features for ASC have been found to differentiate it from PSC-BPPV limiting the test's use for this variant. 3, according to Oxford Center for Evidence-Based Medicine Laryngoscope, 134:2405-2410, 2024.

중년 비만 여성의 아바타 모델링을 위한 체형 연구

This study categorized and analyzed the body types of middle-aged obese women, aged 40-59, based on the characteristics of their shapes for the purpose of 3D avatar modeling. Data from 149 middle-aged obese women were utilized, as provided by the 'Size Korea 8th Body Measurement Survey,' consisting of 3D measurement data. Eleven body type factors were extracted. The data was analyzed through factor analysis and classified into four body types.Type 1 represents a curved body shape with pronounced curves, Type 2 is characterized by well-developed lower body and a stooped posture, Type 3 exhibits a straight body shape with minimal curves, and Type 4 features long legs and development of upper body with a leaning posture.

Assessment of the Comfort Gradient in Leaning Posture among Elderly Individuals

This study aims to investigate the comfort gradient associated with leaning posture in elderly individuals. The assessment of comfort gradient is crucial in understanding the ergonomic needs of this population, as it directly impacts their overall well-being and quality of life. By examining the various factors influencing comfort levels during leaning postures, this research seeks to provide valuable insights for designing supportive and comfortable environments for elderly individuals. The findings of this study will contribute to the existing body of knowledge on ergonomics and assist in the development of interventions to enhance the comfort and safety of elderly individuals in various settings.

Priority Seat Intervention Reduces the Anxiety of the Elderly With Hypertension in the Waiting Room of the North Kuta Health Center, Tourist Area in Badung

People of more than sixty years of age known as elderlies or “Lansia” (bahasa Indonesia). The number of elderlies in millennial era are increasing and they have potential to live better and longer. The Covid-19 pandemic is fear haunted elderlies of high blood pressure that make them anxiety to come to the Puskesmas of North Kuta for having Health Control (Checking-up). Physically the elderlies are decreasing progressively such as the strength of mussels, arm strength mussels decrease for about 16-40%, and physical coordination is also decreasing, so they need the tools to do the activities. New habit is implemented at Puskesmas North Kuta such as social distancing when sitting to avoid physical contact and contagious diseases. The chairs of the waiting room for elderlies are not suitable for anthropometries of elderlies, so they are not comfortable when sitting, the chairs are too low, leaning position are also too low, minimum arms rest so make them difficulties when sitting or standing up. Currently priority chairs are not yet available for elderlies at the waiting room of Puskesmas of North Kuta. The objective of this research is to identify the ideal anthropometry chairs for elderlies and to design prototype chairs for elderlies at the waiting room of Puskesmas North Kuta. The method used is the basic measurement anthropometry and to measure the tiredness of Nordic body map. This research used a pre-experimental oe grup pre-tes,post test design a prototype of priority chairs for elderly people in the waiting room of the Community Health Center. The priority chairs for elderlies are made based on the measurement of elderlies when sitting: height of elbows when sitting; height of popliteal; width of hip and height of shoulders when sitting. Conclusions: Every elderly has the right to get the comfortable facilities when doing the activities and comfortable when sitting in the waiting room of Puskesmas

Stabilizing leaning postures with feedback controlled functional neuromuscular stimulation after trunk paralysis.

Spinal cord injury (SCI) can cause paralysis of trunk and hip musculature that negatively impacts seated balance and ability to lean away from an upright posture and interact fully with the environment. Constant levels of electrical stimulation of peripheral nerves can activate typically paralyzed muscles and aid in maintaining a single upright seated posture. However, in the absence of a feedback controller, such seated postures and leaning motions are inherently unstable and unable to respond to perturbations. Three individuals with motor complete SCI who had previously received a neuroprosthesis capable of activating the hip and trunk musculature volunteered for this study. Subject-specific muscle synergies were identified through system identification of the lumbar moments produced via neural stimulation. Synergy-based calculations determined the real-time stimulation parameters required to assume leaning postures. When combined with a proportional, integral, derivative (PID) feedback controller and an accelerometer to infer trunk orientation, all individuals were able to assume non-erect postures of 30-40° flexion and 15° lateral bending. Leaning postures increased forward reaching capabilities by 10.2, 46.7, and 16 cm respectively for each subject when compared with no stimulation. Additionally, the leaning controllers were able to resist perturbations of up to 90 N, and all subjects perceived the leaning postures as moderately to very stable. Implementation of leaning controllers for neuroprostheses have the potential of expanding workspaces, increasing independence, and facilitating activities of daily living for individuals with paralysis.

Transition from upright to greater forward lean posture predicts faster acceleration during the run-to-sprint transition.

BackgroundForward body lean and greater horizontal ground reaction force have been associated with being able to accelerate during running. However, kinematic features which may predict acceleration during the run-to-sprint transition have not been determined. The purpose of this study was to determine which kinematic changes occur in recreationally active adults and which kinematic features may predict greater acceleration during the run-to-sprint transition. MethodsForty-seven healthy adults completed straight line running along a 30 m track by running in at ∼4 m.s-1. A minimum of 20 trials were completed, with 25 % triggering a light to signal the participant to accelerate as fast as possible. Step characteristics (velocity, length, duration, cadence) and kinematics (neck, trunk, hip, knee and ankle angles and excursions) were determined using a radar gun and inertial measurement units, respectively. ANOVA was used to determine the step-to-step differences and a multiple linear regression was used to determine the relationship between kinematics and acceleration. ResultsThere was an initial increase in trunk flexion angle during early acceleration (p < 0.001) with knee joint excursion significantly lower (p < 0.001) during loading and propulsion compared to the run-in steps. Greater acceleration was predicted using a stepwise linear regression by five variables including less neck flexion excursion and trunk flexion angle during swing of the 1st step, greater trunk flexion angle and extension excursion of the neck during propulsion of the 2nd step and greater hip flexion angle at foot strike of the 3rd step (r2 =0.804, p < 0.001). SignificanceFaster acceleration was observed when participants transitioned from an upright posture to greater forward trunk lean in the early phase of acceleration. Training the run-to-sprint transition, which was shown to have the greatest increase in velocity over the first 5 m, may be encouraged as a sports specific exercise.

Aerodynamic Study of MotoGP Motorcycle Flow Redirectors

In recent years, the introduction of aerodynamic appendages and the study of their aerodynamic performance in MotoGP motorcycles has increased exponentially. It was in 2016, with the introduction of the single electronic control unit, that the search began for alternative methods to generate downforce that were not solely reliant on the motorcycle’s electronics. Since then, all types of spoilers, fins and wings have been observed on the fairings of MotoGP motorcycles. The latest breakthrough has been Ducati’s implementation of flow redirectors at the front and bottom of the fairing. The aim of the present study was to test two hypotheses regarding the performance of the flow redirector by responding to the corresponding research questions on its aerodynamic function and advantage, both in the straight and leaning position. In a preanalytical cognitive act, a visual study of MotoGP motorcycles was conducted and, accordingly, a 3D-CAD model was designed ad hoc in compliance with the FIM 2022 regulations for both the motorcycle and flow redirector. Numerical simulations using OpenFOAM software were then carried out for the aerodynamic analysis. Finally, the Taguchi methodology was applied as an effective simulation-based strategy to narrow down the combinations of geometric parameters, reduce the solution space, optimize the number of simulations, and statistically analyse the results. The aerodynamic performance of the flow redirector is highly dependent on the inlet flow when the motorcycle is in a straight position. The results indicate that all models with leaned motorcycle bearing the flow redirector, regardless of geometry, have an aerodynamic advantage, as the appendage generates downforce with a minimal increment of the drag coefficient. In a cornering situation, the flow separator in the flow redirector reduces the disadvantageous influence of wheel rotation on the “diffuser effect” by drawing the flow towards the outside of the curve, creating extra downforce.

Variation in cardiopulmonary restoration due to bodily posture post-submaximal exercise in collegiate athletes.

The body's anatomical position can influence the autonomic response to return to homeostasis following high intensity exercise. Discrepancies exist as to which body position is considered optimal and practical. This study intends to examine three recovery positions post submaximal exercise to determine which body position would be the most efficient in terms of excess post-exercise oxygen consumption and heart rate recovery. NCAA Division I athletes (N.=17) from multiple sport teams completed three submaximal exercise tests utilizing the Bruce Protocol. Excess post-exercise oxygen consumption and heart rate recovery were measured at peak exercise and at 1-, 5-, and 10-minute time intervals during the recovery phase while assuming a recovery position: supine, trunk forward leaning, and standing vertical. Statistical analysis showed the 1-minute excess post-exercise oxygen consumption associated with supine recovery (1725±348 mL/kg) was significantly greater than standing vertical (1578±340 mL/kg, P=0.024). At 5 minutes, supine excess post-exercise oxygen consumption (3557±760 mL/kg) was significantly less than trunk forward leaning (4054±777 mL/kg, P=0.0001) and trunk forward leaning was significantly greater than standing vertical (3776±700 mL/kg, P=0.008). At 10 minutes, supine excess post-exercise oxygen consumption (5246±961 mL/kg) was significantly less than both the standing vertical position (5878±1042 mL/kg, P=0.0099), and the trunk forward leaning position (6749±1223 mL/kg, P<0.0001). Supine had the highest heart rate recovery at 1-, 5-, and 10-minutes post exercise. The supine position proved to be the most optimal during the 10-minute recovery period, while the trunk forward leaning position showed to be a more advantageous position for short-term recovery.

Spatial characteristics of reactive stepping among people living with chronic incomplete spinal cord injury

Objective: Compare the spatial characteristics of reactive stepping between individuals with chronic motor incomplete spinal cord injuries (iSCI) and able-bodied (AB) individuals. Design: Cross sectional. Setting: Lyndhurst Centre. Participants: Twelve individuals with iSCI (3 males, 53.6 ± 15.2 years old) and 11 age- and sex-matched AB individuals (3 males, 54.8 ± 14.0 years old). Interventions: The Lean-and-Release test was used to elicit reactive stepping. A horizontal cable, attached at waist height, was released when 8-12% body weight was supported in a forward lean position. Participants underwent up to 10 Lean-and-Release trials in a session. Kinematic and kinetic data were recorded. Outcome measures: The length, width and height of the first reactive step of each trial were calculated. Standard deviation between trials was calculated to represent the variability in step length, width and height within a participant. Among participants with iSCI, correlation coefficients were used to explore the relationship between step length and width variability and (1) Lean-and-Release test behavioral responses, (2) 3-month fall history, and (3) lower extremity strength. Results: Step length (P = 0.94), width (P = 0.52) and height (P = 0.97), normalized for participant height, did not differ between groups. Participants with iSCI showed greater variability in step length (P = 0.02) and width (P = 0.01), but not height (P = 0.32). No correlation was found between step length or width variability and behavioral responses, 3-month fall history, or lower extremity strength. Conclusions: Individuals with iSCI showed increased variability in length and width of reactive stepping compared to AB individuals, which may contribute to their impaired ability to execute single-step reactive responses. Trial registration: ClinicalTrials.gov identifier: NCT02960178.

Evaluation of the physiological benefits of a passive back-support exoskeleton during lifting and working in forward leaning postures

Musculoskeletal disorders affecting the back are highly prevalent in fields of occupation involving repetitive lifting and working in forward leaning postures. Back-support exoskeletons are developed to relieve workers in physically demanding occupations. This study investigates the physiological effects of a lightweight exoskeleton which provides support through textile springs worn on the back. We hypothesized that wearing such a passive back-support exoskeleton reduces muscle activity of the back and hip muscles, while not influencing abdominal muscle activity and movement kinematics during typical occupational tasks.We collected electromyography data from the main back and hip muscles as well as whole body kinematics data via optical motion tracking during a set of relevant weight lifting tasks corresponding to typical work conditions. In our sample of 30 healthy volunteers, wearing the exoskeleton significantly reduced muscle activity, with reductions up to 25.59% during forward leaning and 20.52% during lifting in the main back and hip muscles (Erector Spinae at thoracic and lumbar level and Quadratus Lumborum). Simultaneously, no changes in knee and hip range of motion were observed. The stretch of the textile springs correlated with the body mass index and chest circumference of the wearer, and depended on posture, but not on the lifted load.The LiftSuit exoskeleton relieved back and hip muscles during typically straining occupational tasks, while biomechanical parameters were preserved. This suggests that passive lift-support exoskeletons can be safely used to relieve workers during lifting and forward leaning tasks.

A method to quantify the reduction of back and hip muscle fatigue of lift-support exoskeletons.

Cumulative back muscle fatigue plays a role in the occurrence of low-back injuries in occupations that require repetitive lifting of heavy loads and working in forward leaning postures. Lift-support exoskeletons have the potential to reduce back and hip muscle activity, thereby delaying the onset of fatigue in these muscles. Therefore, exoskeletons are being considered a potentially important tool to further reduce workload-related injuries. However, today no standards have been established on how to benchmark the support level of lift-support exoskeletons. This work proposes an experimental protocol to quantify the support level of a lift-support exoskeletons on instant changes in muscle activity and fatigue development while maintaining a static forward leaning posture. It then applies the protocol to experimentally assess the effect of the support provided by a commercially available lift-support exoskeleton, the LiftSuit 2.0 (Auxivo AG, Schwerzenbach, Switzerland), on the user. In a sample of 14 participants, the amplitude of the muscle activity of the back muscles and hip muscles () was significantly reduced. Wearing the exoskeleton significantly reduced the amount of fatigue developed during the task (). Changes in muscle fatigue can be objectively recorded and correlated with relevant changes for exoskeleton users: the time a task can be performed and perceived low-back fatigue. Thus, including such measures of fatigue in standardized benchmarking procedures will help quantify the benefits of exoskeletons for occupational use.

Improving Walking Autonomy of People with Paraplegia wearing Powered Exoskeletons

Normal walking involves shifting the body's center of mass (CoM) forward in order to walk more efficiently. Unfortunately, people with paraplegia cannot voluntarily control their CoM due to their inability to move their legs or waist. Powered exoskeletons have been considered as one of the major lower limb assistive devices and developed to assist people with paraplegia to walk again. However, powered exoskeletons have limited degrees of freedom (DoFs), so they cannot fully assist with CoM control without the aid of physical therapists. Therefore, it is challenging for people with paraplegia to completely control their CoM for walking, even with the assistance of a powered exoskeleton.To address this issue, this paper focused on improving the walking autonomy of people with paraplegia wearing powered exoskeletons. Therefore, we propose a new gait pattern method that utilizes a leaning posture to effectively shift the body's CoM forward of people with paraplegia wearing powered exoskeletons. By taking advantage of the height difference between the leading and trailing leg, the proposed method facilitates the movement of the body's CoM forward during walking. To assess the efficacy of the proposed gait pattern method, the user's trunk was tilted up to 2 degrees. During the preswing phase, for every one-degree increase in the angle of the trunk tilt, the initial frontal acceleration of the user's CoM maximally rose up to 16%.

Multimodal Differentiation for Allophone Pupils in First Language French Classroom

Language classroom interactions can be characterized as multimodal, since teachers may resort to a variety of resources provided by their body or by their immediate space in order to convey meaning, manage activities and assess pupils’ performances. Furthermore, teachers’ multimodal practices constitute an essential component for the differentiating process aiming to resolve especially linguistic problems some pupils may face. In this perspective, this study examines the implementation of multimodal differentiation by the same teacher in the case of allophone pupils following first language French courses alongside with native pupils of 3rd grade within the context of inclusion classroom in a middle school in France. More specifically, it was aimed to analyze a teacher’s adaptation of kinesic and proxemic behaviors within the differentiation process, such as the use of hand gestures, gaze and facial expressions as bodily resources but also the control of interpersonal distance with respect to allophone pupils. For this purpose, a micro-ethnographic research strategy was applied, and data was collected through video-recorded sessions of the teacher in inclusion classroom. Our qualitative analysis of the data revealed a differentiated use of prosodic, kinesic and proxemic elements by the teacher, such as the reduction of speech rate, the accentuation of words, the production of deictic and iconic hand gestures as well as facial expressions, the orientation of gaze, the forward leaning posture, the isolated seating arrangement, and the reduction of interpersonal distance. All these elements either follow or overlap each other, especially within the framework of teacher instructions during classroom activities.

Adverse Effects of Prolonged Sitting Behaviour on the General Health and Posture of Medical Students

Objectives: To determine the prevalence of musculoskeletal symptoms among Medical students and to correlate the musculoskeletal adverse effects with prolonged sitting and sitting posture.&#x0D; Study Design: Analytical cross-sectional study.&#x0D; Place and Duration of Study: Study was conducted online among Medical Students studying in various medical institutions across Pakistan, from Nov 2021 to Apr 2022.&#x0D; Methodology: Study included 144 Medical and Dental students, recruited through convenience sampling. Any participant currently suffering or recently recovered from a debilitating illness, physical disability, presently undergoing treatment for any chronic muscular or skeletal pain was not included in the study. A close-ended virtual questionnaire containing the Nordic Musculoskeletal Questionnaire (NMQ) was used. &#x0D; Results: Majority of respondents 100(69.4%) sat continuously for more than 2 hours while 44(30.6%) sat for less than 2 hours in a single seating. Results of the NMQ showed that most people had pain and discomfort in shoulder, upper back, lower back and hip. Pain in the lower back was the most common complaint 93(65%). Prolonged sitting (&gt;2hours) was significantly associated with Lower back pain (p=0.004) and hip pain (p=0.019)&#x0D; Conclusion: Prolonged sitting behaviour was associated with frequent complaints of lower back discomfort. Poor posture was demonstrated to cause pain in the shoulder and upper back regions. Active workstations, intermittent walks during breaks and usage of negative desks, as well as avoidance of forward leaning posture are suggested to improve working conditions.

Advances in Human Biodynamic Modeling for Analysis of Whole-Body Vibrations

Low-frequency road surface or rail track inputs play an important role since humans are most susceptible to whole body vibration when in erect, seated backrest, forward lean postures. Therefore, biodynamic human subject modelling and simulation has been an area of key interest for the researchers in the past. The study reveals that the first lumped parameter single degree of freedom (DoF) model was considered by Cormann in 1962. Since then, several researchers investigated the influence of posture, vibration amplitudes and STH and BTH transmissibility analysis using different lumped parameter models starting from the basic single DoF to a complex 11 DoF models considering all possible human segments for the analysis. This paper acknowledges all those works carried out in the past.

Muscle Activity and Aerodynamic Voice Changes at Different Body Postures: A Pilot Study

Body posture is a commonly discussed component of voice training and therapy. However, body postures, postural changes, related posturing muscle monitoring, and the potential changes in voice production (eg, glottal aerodynamic changes, acoustic differences) have been inconsistently described in the literature, leaving room for free interpretation and possible misunderstandings. The primary purpose of this pilot study was to compare the magnitude of electromyographical activation of muscles involved in phonation-breathing functions and their changes due to four standardized body postures in experienced singers. Secondly, to identify which body posture produces greater changes in aerodynamic parameters, vocal pitch, and loudness. Eight healthy adults with experience in singing voice performed a vocal task during different body postures commonly used in both voice training and therapy. A 3D-capture system was used to control and quantify the alignment of each posture. During the performances, surface electromyography (sEMG) was used to measure the muscular activity involved in the breathing/phonation and posture processes. A nonparametric Kruskal-Wallis test was used to compare the sEMG activity of phonatory muscles and aerodynamic voice variables between postures. Our study did not reveal significant differences in sEMG activity, aerodynamic parameters, vocal pitch, and loudness among body postures during vocal task productions. However, the vocal pitch (in semitones) revealed significant differences in the unstable surface when compared to the upright posture, modified upright, and leaning postures. The body postures selected did not generate voice aerodynamic modifications of the voice nor in the levels of activation of muscles involved in the phonation-breathing process in individuals with experience in singing voice. Modifications of body posture as a tool for voice therapy should be further investigated, considering the population with voice problems and no voice training experience.

Midfrontal theta dynamics index the monitoring of postural stability.

Stepping is a common strategy to recover postural stability and maintain upright balance. Postural perturbations have been linked to neuroelectrical markers such as the N1 potential and theta frequency dynamics. Here, we investigated the role of cortical midfrontal theta dynamics of balance monitoring, driven by balance perturbations at different initial standing postures. We recorded electroencephalography, electromyography, and motion tracking of human participants while they stood on a platform that delivered a range of forward and backward whole-body balance perturbations. The participants' postural threat was manipulated prior to the balance perturbation by instructing them to lean forward or backward while keeping their feet-in-place in response to the perturbation. We hypothesized that midfrontal theta dynamics index the engagement of a behavioral monitoring system and, therefore, that perturbation-induced theta power would be modulated by the initial leaning posture and perturbation intensity. Targeted spatial filtering in combination with mixed-effects modeling confirmed our hypothesis and revealed distinct modulations of theta power according to postural threat. Our results provide novel evidence that midfrontal theta dynamics subserve action monitoring of human postural balance. Understanding of cortical mechanisms of balance control is crucial for studying balance impairments related to aging and neurological conditions (e.g. stroke).