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Sample records for body posture evaluation

  1. Global Body Posture Evaluation in Patients with Temporomandibular Joint Disorder

    PubMed Central

    Saito, Eliza Tiemi; Akashi, Paula Marie Hanai; de Camargo Neves Sacco, Isabel

    2009-01-01

    AIM: To identify the relationship between anterior disc displacement and global posture (plantar arches, lower limbs, shoulder and pelvic girdle, vertebral spine, head and mandibles). Common signs and symptoms of anterior disc displacement were also identified. INTRODUCTION: Global posture deviations cause body adaptation and realignment, which may interfere with the organization and function of the temporomandibular joint. METHODS : Global posture evaluation was performed in a group of 10 female patients (20 to 30 years of age) with temporomandibular joint disc displacement and in a control group of 16 healthy female volunteers matched for age, weight and height. Anterior disc displacement signs, symptoms and the presence of parafunctional habits were also identified through interview. RESULTS: Patients with disc displacement showed a higher incidence of pain in the temporomandibular joint area, but there were no differences in parafunctional habits between the groups. In the disc displacement group, postural deviations were found in the pelvis (posterior rotation), lumbar spine (hyperlordosis), thoracic spine (rectification), head (deviation to the right) and mandibles (deviation to the left with open mouth). There were no differences in the longitudinal plantar arches between the groups. CONCLUSION: Our results suggest a close relationship between body posture and temporomandibular disorder, though it is not possible to determine whether postural deviations are the cause or the result of the disorder. Hence, postural evaluation could be an important component in the overall approach to providing accurate prevention and treatment in the management of patients with temporomandibular disorder. PMID:19142549

  2. Evaluation of Neutral Body Posture on Shuttle Mission STS-57 (SPACEHAB-1). Revision

    NASA Technical Reports Server (NTRS)

    Mount, Frances E.; Whitmore, Mihriban; Stealey, Sheryl L.

    2003-01-01

    Research has shown that the space environment induces physiological changes in the human body, such as fluid shifts in the upper body and chest cavity, spinal lengthening, muscular atrophy, space motion sickness, cardiopulmonary deconditioning, and bone mass loss, as well as some changes in visual perception. These require a period of adaptation and can substantially affect both crew member performance and posture. These physiological effects, when work activities are conducted, have been known to impact the body's center of gravity, reach, flexibility, and dexterity. All these aspects of posture must be considered to safely and efficiently design space systems and hardware. NASA has documented its microgravity body posture in the Man-Systems Integration Standards (MSIS); the space community uses the MSIS posture to design workstations and tools for space application. However, the microgravity body posture should be further investigated for several reasons, including small sample size in previous studies, possible imprecision, and lack of detail. JSC undertook this study to investigate human body posture exhibited under microgravity conditions. STS-57 crew members were instructed to assume a relaxed posture that was not oriented to any work area or task. Crew members were asked to don shorts and tank tops and to be blindfolded while data were recorded. Video data were acquired once during the mission from each of the six crew members. No one crew member exhibited the typical NBP called out in the MSIS; one composite posture is not adequate. A range of postures may be more constructive for design purposes. Future evaluations should define precise posture requirements for workstation, glove box, maintenance, foot-restraint, and handhold activities.

  3. Physics-based Simulation of Human Posture Using 3D Whole Body Scanning Technology for Astronaut Space Suit Evaluation

    NASA Technical Reports Server (NTRS)

    Kim, Kyu-Jung

    2005-01-01

    Over the past few years high precision three-dimensional (3D) full body laser scanners have been developed to be used as a powerful anthropometry tool for quantification of the morphology of the human body. The full body scanner can quickly extract body characteristics in non-contact fashion. It is required for the Anthropometry and Biomechanics Facility (ABF) to have capabilities for kinematics simulation of a digital human at various postures whereas the laser scanner only allows capturing a single static posture at each time. During this summer fellowship period a theoretical study has been conducted to estimate an arbitrary posture with a series of example postures through finite element (FE) approximation and found that four-point isoparametric FE approximation would result in reasonable maximum position errors less than 5%. Subsequent pilot scan experiments demonstrated that a bead marker with a nominal size of 6 mm could be used as a marker for digitizing 3-D coordinates of anatomical landmarks for further kinematic analysis. Two sessions of human subject testing were conducted for reconstruction of an arbitrary postures from a set of example postures for each joint motion for the forearm/hand complex and the whole upper extremity.

  4. Body Posture Facilitates Retrieval of Autobiographical Memories

    ERIC Educational Resources Information Center

    Dijkstra, Katinka; Kaschak, Michael P.; Zwaan, Rolf A.

    2007-01-01

    We assessed potential facilitation of congruent body posture on access to and retention of autobiographical memories in younger and older adults. Response times were shorter when body positions during prompted retrieval of autobiographical events were similar to the body positions in the original events than when body position was incongruent.…

  5. The representation of self reported affect in body posture and body posture simulation.

    PubMed

    Grammer, Karl; Fink, Bernhard; Oberzaucher, Elisabeth; Atzmüller, Michaela; Blantar, Ines; Mitteroecker, Philipp

    2004-01-01

    It is taken for granted that the non-verbal information we acquire from a person's body posture and position affects our perception of others. However, to date human postures have never been described on an empirical level. This study is the first approach to tackle the unexplored topic of human postures. We combined two approaches: traditional behavior observation and modern anthropometric analysis. Photographs of 100 participants were taken, their body postures were transferred to a three dimensional virtual environment and the occurring body angles were measured. The participants were asked to fill in a questionnaire about their current affective state. A principal component analysis with the items of the affect questionnaire (Positive Negative Affect Scales, PANAS) revealed five main factors: aversion, openness, irritation, happiness, and self-confidence. The body angles were then regressed on these factors and the respective postures were reconstructed within a virtual environment. 50 different subjects rated the reconstructed postures from the positive and negative end of the regression. We found the ratings to be valid and accurate in respect to the five factors. PMID:15571090

  6. Examination of the relationship between mandibular position and body posture.

    PubMed

    Sakaguchi, Kiwamu; Mehta, Noshir R; Abdallah, Emad F; Forgione, Albert G; Hirayama, Hiroshi; Kawasaki, Takao; Yokoyama, Atsuro

    2007-10-01

    The purpose of this study was to evaluate the effect of changing mandibular position on body posture and reciprocally, body posture on mandibular position. Forty-five (45) asymptomatic subjects (24 males and 21 females, ages 21-53 years, mean age 30.7 years) were included in this study and randomly assigned to one of two groups, based on the table of random numbers. The only difference between group I and group II was the sequence of the testing. The MatScan (Tekscan, Inc., South Boston, MA) system was used to measure the result of changes in body posture (center of foot pressure: COP) while subjects maintained the following 5 mandibular positions: (1) rest position, (2) centric occlusion, (3) clinically midlined jaw position with the labial frena aligned, (4) a placebo wax appliance, worn around the labial surfaces of the teeth and (5) right eccentric mandibular position. The T-Scan II (Tekscan, Inc., South Boston, MA) system was used to analyze occlusal force distribution in two postural positions, with and without a heel lift under the right foot. Total trajectory length of COP in centric occlusion was shorter than in the rest position (p < 0.05). COP area in right eccentric mandibular position was larger than in centric occlusion (p < 0.05). When subjects used a heel lift under the right foot, occlusal forces shifted to the right side compared to no heel lift (p < 0.01). Based on these findings, it was concluded that changing mandibular position affected body posture. Conversely, changing body posture affected mandibular position.

  7. Static body postural misalignment in individuals with temporomandibular disorders: a systematic review

    PubMed Central

    Chaves, Thaís C.; Turci, Aline M.; Pinheiro, Carina F.; Sousa, Letícia M.; Grossi, Débora B.

    2014-01-01

    BACKGROUND: The association between body postural changes and temporomandibular disorders (TMD) has been widely discussed in the literature, however, there is little evidence to support this association. OBJECTIVES: The aim of the present study was to conduct a systematic review to assess the evidence concerning the association between static body postural misalignment and TMD. METHOD: A search was conducted in the PubMed/Medline, Embase, Lilacs, Scielo, Cochrane, and Scopus databases including studies published in English between 1950 and March 2012. Cross-sectional, cohort, case control, and survey studies that assessed body posture in TMD patients were selected. Two reviewers performed each step independently. A methodological checklist was used to evaluate the quality of the selected articles. RESULTS: Twenty studies were analyzed for their methodological quality. Only one study was classified as a moderate quality study and two were classified as strong quality studies. Among all studies considered, only 12 included craniocervical postural assessment, 2 included assessment of craniocervical and shoulder postures,, and 6 included global assessment of body posture. CONCLUSION: There is strong evidence of craniocervical postural changes in myogenous TMD, moderate evidence of cervical postural misalignment in arthrogenous TMD, and no evidence of absence of craniocervical postural misalignment in mixed TMD patients or of global body postural misalignment in patients with TMD. It is important to note the poor methodological quality of the studies, particularly those regarding global body postural misalignment in TMD patients. PMID:25590441

  8. Emotion expression in body action and posture.

    PubMed

    Dael, Nele; Mortillaro, Marcello; Scherer, Klaus R

    2012-10-01

    Emotion communication research strongly focuses on the face and voice as expressive modalities, leaving the rest of the body relatively understudied. Contrary to the early assumption that body movement only indicates emotional intensity, recent studies have shown that body movement and posture also conveys emotion specific information. However, a deeper understanding of the underlying mechanisms is hampered by a lack of production studies informed by a theoretical framework. In this research we adopted the Body Action and Posture (BAP) coding system to examine the types and patterns of body movement that are employed by 10 professional actors to portray a set of 12 emotions. We investigated to what extent these expression patterns support explicit or implicit predictions from basic emotion theory, bidimensional theory, and componential appraisal theory. The overall results showed partial support for the different theoretical approaches. They revealed that several patterns of body movement systematically occur in portrayals of specific emotions, allowing emotion differentiation. Although a few emotions were prototypically expressed by one particular pattern, most emotions were variably expressed by multiple patterns, many of which can be explained as reflecting functional components of emotion such as modes of appraisal and action readiness. It is concluded that further work in this largely underdeveloped area should be guided by an appropriate theoretical framework to allow a more systematic design of experiments and clear hypothesis testing.

  9. Changes in the body posture of women occurring with age

    PubMed Central

    2013-01-01

    Background A current topic in the field of geriatrics still needing a great deal of study is the changes in body posture occurring with age. Symptoms of these changes can be observed starting between the ages of 40–50 years with a slow progression that increases after 60 years of age. The aims of this study were to evaluate parameters characterizing the posture of women over the age of 60 years compared with a control group and to determine the dynamics of body posture changes in the following decades. Methods The study included 260 randomly selected women. The study group consisted of 130 women between the ages of 60–90 years (Older Women). The control group (Younger Women) consisted of 130 women between the ages of 20–25 years (posture stabilization period). The photogrammetric method was used to evaluate body posture using the phenomenon of the projection chamber. The study was conducted according to generally accepted principles. Results In the analysis of parameters characterizing individual slope curves, results were varied among different age groups. The lumbar spine slope did not show significant differences between different age groups (p = 0.6952), while statistically significant differences (p = 0.0000) were found in the thoracic-lumbar spine slope (p = 0.0033) and upper thoracic spine slope. Body angle was shown to increase with age (p = 0.0000). Thoracic kyphosis depth significantly deepened with age (p = 0.0002), however, the thoracic kyphosis angle decreased with age (p = 0.0000). An increase in asymmetries was noticed, provided by a significantly higher angle of the shoulder line (p = 0.0199) and the difference in height of the lower shoulder blade angle (p = 0.0007) measurements in the group of older women. Conclusions Changes in the parameters describing body posture throughout consecutive decades were observed. Therapy for women over the age of 60 years should involve strengthening of the erector spinae

  10. Turning Configural Processing Upside Down: Part and Whole Body Postures

    ERIC Educational Resources Information Center

    Reed, Catherine L.; Stone, Valerie E.; Grubb, Jefferson D.; McGoldrick, John E.

    2006-01-01

    Like faces, body postures are susceptible to an inversion effect in untrained viewers. The inversion effect may be indicative of configural processing, but what kind of configural processing is used for the recognition of body postures must be specified. The information available in the body stimulus was manipulated. The presence and magnitude of…

  11. Analysis of Relationship between the Body Mass Composition and Physical Activity with Body Posture in Children

    PubMed Central

    Baran, Joanna; Czenczek-Lewandowska, Ewelina; Leszczak, Justyna; Mazur, Artur

    2016-01-01

    Introduction. Excessive body mass in turn may contribute to the development of many health disorders including disorders of musculoskeletal system, which still develops intensively at that time. Aim. The aim of this study was to assess the relationship between children's body mass composition and body posture. The relationship between physical activity level of children and the parameters characterizing their posture was also evaluated. Material and Methods. 120 school age children between 11 and 13 years were enrolled in the study, including 61 girls and 59 boys. Each study participant had the posture evaluated with the photogrammetric method using the projection moiré phenomenon. Moreover, body mass composition and the level of physical activity were evaluated. Results. Children with the lowest content of muscle tissue showed the highest difference in the height of the inferior angles of the scapulas in the coronal plane. Children with excessive body fat had less slope of the thoracic-lumbar spine, greater difference in the depth of the inferior angles of the scapula, and greater angle of the shoulder line. The individuals with higher level of physical activity have a smaller angle of body inclination. Conclusion. The content of muscle tissue, adipose tissue, and physical activity level determines the variability of the parameter characterizing the body posture. PMID:27761467

  12. Emotional and movement-related body postures modulate visual processing.

    PubMed

    Borhani, Khatereh; Làdavas, Elisabetta; Maier, Martin E; Avenanti, Alessio; Bertini, Caterina

    2015-08-01

    Human body postures convey useful information for understanding others' emotions and intentions. To investigate at which stage of visual processing emotional and movement-related information conveyed by bodies is discriminated, we examined event-related potentials elicited by laterally presented images of bodies with static postures and implied-motion body images with neutral, fearful or happy expressions. At the early stage of visual structural encoding (N190), we found a difference in the sensitivity of the two hemispheres to observed body postures. Specifically, the right hemisphere showed a N190 modulation both for the motion content (i.e. all the observed postures implying body movements elicited greater N190 amplitudes compared with static postures) and for the emotional content (i.e. fearful postures elicited the largest N190 amplitude), while the left hemisphere showed a modulation only for the motion content. In contrast, at a later stage of perceptual representation, reflecting selective attention to salient stimuli, an increased early posterior negativity was observed for fearful stimuli in both hemispheres, suggesting an enhanced processing of motivationally relevant stimuli. The observed modulations, both at the early stage of structural encoding and at the later processing stage, suggest the existence of a specialized perceptual mechanism tuned to emotion- and action-related information conveyed by human body postures. PMID:25556213

  13. Emotional and movement-related body postures modulate visual processing.

    PubMed

    Borhani, Khatereh; Làdavas, Elisabetta; Maier, Martin E; Avenanti, Alessio; Bertini, Caterina

    2015-08-01

    Human body postures convey useful information for understanding others' emotions and intentions. To investigate at which stage of visual processing emotional and movement-related information conveyed by bodies is discriminated, we examined event-related potentials elicited by laterally presented images of bodies with static postures and implied-motion body images with neutral, fearful or happy expressions. At the early stage of visual structural encoding (N190), we found a difference in the sensitivity of the two hemispheres to observed body postures. Specifically, the right hemisphere showed a N190 modulation both for the motion content (i.e. all the observed postures implying body movements elicited greater N190 amplitudes compared with static postures) and for the emotional content (i.e. fearful postures elicited the largest N190 amplitude), while the left hemisphere showed a modulation only for the motion content. In contrast, at a later stage of perceptual representation, reflecting selective attention to salient stimuli, an increased early posterior negativity was observed for fearful stimuli in both hemispheres, suggesting an enhanced processing of motivationally relevant stimuli. The observed modulations, both at the early stage of structural encoding and at the later processing stage, suggest the existence of a specialized perceptual mechanism tuned to emotion- and action-related information conveyed by human body postures.

  14. An experimental study to evaluate musculoskeletal disorders and postural stress of female craftworkers adopting different sitting postures.

    PubMed

    Maity, Payel; De, Sujaya; Pal, Amitava; Dhara, Prakash C

    2016-01-01

    This study aimed to evaluate musculoskeletal disorders (MSDs) and postural stress among female craftworkers. The study was carried out on 75 adult female craftworkers in different districts of West Bengal. The prevalence of MSDs, body part discomfort (BPD) rating and body joint angles of the workers were evaluated with standard methods. Electromyography (EMG) of the shoulder and back muscles was recorded with the BIOPAC system. The prevalence of MSDs, BPD rating and deviation of joint angle were comparatively lower in the case of sitting on the floor with folded legs than squatting and sitting on the floor with stretched legs postures. The EMG and rms values of the shoulder and back muscles were comparatively lower in this posture. Therefore, it was concluded that sitting on the floor with folded legs was less hazardous and it imposed less postural stress in comparison to other sitting postures. PMID:27055480

  15. Nonplantigrade Foot Posture: A Constraint on Dinosaur Body Size.

    PubMed

    Kubo, Tai; Kubo, Mugino O

    2016-01-01

    Dinosaurs had functionally digitigrade or sub-unguligrade foot postures. With their immediate ancestors, dinosaurs were the only terrestrial nonplantigrades during the Mesozoic. Extant terrestrial mammals have different optimal body sizes according to their foot posture (plantigrade, digitigrade, and unguligrade), yet the relationship of nonplantigrade foot posture with dinosaur body size has never been investigated, even though the body size of dinosaurs has been studied intensively. According to a large dataset presented in this study, the body sizes of all nonplantigrades (including nonvolant dinosaurs, nonvolant terrestrial birds, extant mammals, and extinct Nearctic mammals) are above 500 g, except for macroscelid mammals (i.e., elephant shrew), a few alvarezsauroid dinosaurs, and nondinosaur ornithodirans (i.e., the immediate ancestors of dinosaurs). When nonplantigrade tetrapods evolved from plantigrade ancestors, lineages with nonplantigrade foot posture exhibited a steady increase in body size following Cope's rule. In contrast, contemporaneous plantigrade lineages exhibited no trend in body size evolution and were largely constrained to small body sizes. This evolutionary pattern of body size specific to foot posture occurred repeatedly during both the Mesozoic and the Cenozoic eras. Although disturbed by the end-Cretaceous extinction, species of mid to large body size have predominantly been nonplantigrade animals from the Jurassic until the present; conversely, species with small body size have been exclusively composed of plantigrades in the nonvolant terrestrial tetrapod fauna. PMID:26790003

  16. Nonplantigrade Foot Posture: A Constraint on Dinosaur Body Size.

    PubMed

    Kubo, Tai; Kubo, Mugino O

    2016-01-01

    Dinosaurs had functionally digitigrade or sub-unguligrade foot postures. With their immediate ancestors, dinosaurs were the only terrestrial nonplantigrades during the Mesozoic. Extant terrestrial mammals have different optimal body sizes according to their foot posture (plantigrade, digitigrade, and unguligrade), yet the relationship of nonplantigrade foot posture with dinosaur body size has never been investigated, even though the body size of dinosaurs has been studied intensively. According to a large dataset presented in this study, the body sizes of all nonplantigrades (including nonvolant dinosaurs, nonvolant terrestrial birds, extant mammals, and extinct Nearctic mammals) are above 500 g, except for macroscelid mammals (i.e., elephant shrew), a few alvarezsauroid dinosaurs, and nondinosaur ornithodirans (i.e., the immediate ancestors of dinosaurs). When nonplantigrade tetrapods evolved from plantigrade ancestors, lineages with nonplantigrade foot posture exhibited a steady increase in body size following Cope's rule. In contrast, contemporaneous plantigrade lineages exhibited no trend in body size evolution and were largely constrained to small body sizes. This evolutionary pattern of body size specific to foot posture occurred repeatedly during both the Mesozoic and the Cenozoic eras. Although disturbed by the end-Cretaceous extinction, species of mid to large body size have predominantly been nonplantigrade animals from the Jurassic until the present; conversely, species with small body size have been exclusively composed of plantigrades in the nonvolant terrestrial tetrapod fauna.

  17. Nonplantigrade Foot Posture: A Constraint on Dinosaur Body Size

    PubMed Central

    Kubo, Tai; Kubo, Mugino O.

    2016-01-01

    Dinosaurs had functionally digitigrade or sub-unguligrade foot postures. With their immediate ancestors, dinosaurs were the only terrestrial nonplantigrades during the Mesozoic. Extant terrestrial mammals have different optimal body sizes according to their foot posture (plantigrade, digitigrade, and unguligrade), yet the relationship of nonplantigrade foot posture with dinosaur body size has never been investigated, even though the body size of dinosaurs has been studied intensively. According to a large dataset presented in this study, the body sizes of all nonplantigrades (including nonvolant dinosaurs, nonvolant terrestrial birds, extant mammals, and extinct Nearctic mammals) are above 500 g, except for macroscelid mammals (i.e., elephant shrew), a few alvarezsauroid dinosaurs, and nondinosaur ornithodirans (i.e., the immediate ancestors of dinosaurs). When nonplantigrade tetrapods evolved from plantigrade ancestors, lineages with nonplantigrade foot posture exhibited a steady increase in body size following Cope’s rule. In contrast, contemporaneous plantigrade lineages exhibited no trend in body size evolution and were largely constrained to small body sizes. This evolutionary pattern of body size specific to foot posture occurred repeatedly during both the Mesozoic and the Cenozoic eras. Although disturbed by the end-Cretaceous extinction, species of mid to large body size have predominantly been nonplantigrade animals from the Jurassic until the present; conversely, species with small body size have been exclusively composed of plantigrades in the nonvolant terrestrial tetrapod fauna. PMID:26790003

  18. The Relationship Between the Stomatognathic System and Body Posture

    PubMed Central

    Cuccia, Antonino; Caradonna, Carola

    2009-01-01

    In recent years, many researchers have investigated the various factors that can influence body posture: mood states, anxiety, head and neck positions, oral functions (respiration, swallowing), oculomotor and visual systems, and the inner ear. Recent studies indicate a role for trigeminal afferents on body posture, but this has not yet been demonstrated conclusively. The present study aims to review the papers that have shown a relationship between the stomatognathic system and body posture. These studies suggest that tension in the stomatognathic system can contribute to impaired neural control of posture. Numerous anatomical connections between the stomatognathic system’s proprioceptive inputs and nervous structures are implicated in posture (cerebellum, vestibular and oculomotor nuclei, superior colliculus). If the proprioceptive information of the stomatognathic system is inaccurate, then head control and body position may be affected. In addition, the present review discusses the role the myofascial system plays in posture. If confirmed by further research, these considerations can improve our understanding and treatment of muscular-skeletal disorders that are associated with temporomandibular joint disorders, occlusal changes, and tooth loss. PMID:19142553

  19. The relationship between the stomatognathic system and body posture.

    PubMed

    Cuccia, Antonino; Caradonna, Carola

    2009-01-01

    In recent years, many researchers have investigated the various factors that can influence body posture: mood states, anxiety, head and neck positions, oral functions (respiration, swallowing), oculomotor and visual systems, and the inner ear. Recent studies indicate a role for trigeminal afferents on body posture, but this has not yet been demonstrated conclusively. The present study aims to review the papers that have shown a relationship between the stomatognathic system and body posture. These studies suggest that tension in the stomatognathic system can contribute to impaired neural control of posture. Numerous anatomical connections between the stomatognathic system's proprioceptive inputs and nervous structures are implicated in posture (cerebellum, vestibular and oculomotor nuclei, superior colliculus). If the proprioceptive information of the stomatognathic system is inaccurate, then head control and body position may be affected. In addition, the present review discusses the role the myofascial system plays in posture. If confirmed by further research, these considerations can improve our understanding and treatment of muscular-skeletal disorders that are associated with temporomandibular joint disorders, occlusal changes, and tooth loss. PMID:19142553

  20. Functional asymmetry of posture and body system regulation

    NASA Technical Reports Server (NTRS)

    Boloban, V. N.; Otsupok, A. P.

    1980-01-01

    The manifestation of functional asymmetry during the regulation of an athlete's posture and a system of bodies and its effect on the execution of individual and group acrobatic exercises were studied. Functional asymmetry of posture regulation was recorded in acrobats during the execution of individual and group exercises. It was shown that stability is maintained at the expense of bending and twisting motions. It is important to consider whether the functional asymmetry of posture regulation is left or right sided in making up pairs and groups of acrobats.

  1. First-Person Perspective Virtual Body Posture Influences Stress: A Virtual Reality Body Ownership Study

    PubMed Central

    Bergström, Ilias; Kilteni, Konstantina; Slater, Mel

    2016-01-01

    In immersive virtual reality (IVR) it is possible to replace a person’s real body by a life-sized virtual body that is seen from first person perspective to visually substitute their own. Multisensory feedback from the virtual to the real body (such as the correspondence of touch and also movement) can also be present. Under these conditions participants typically experience a subjective body ownership illusion (BOI) over the virtual body, even though they know that it is not their real one. In most studies and applications the posture of the real and virtual bodies are as similar as possible. Here we were interested in whether the BOI is diminished when there are gross discrepancies between the real and virtual body postures. We also explored whether a comfortable or uncomfortable virtual body posture would induce feelings and physiological responses commensurate with the posture. We carried out an experiment with 31 participants in IVR realized with a wide field-of-view head-mounted display. All participants were comfortably seated. Sixteen of them were embodied in a virtual body designed to be in a comfortable posture, and the remainder in an uncomfortable posture. The results suggest that the uncomfortable body posture led to lesser subjective BOI than the comfortable one, but that participants in the uncomfortable posture experienced greater awareness of their autonomic physiological responses. Moreover their heart rate, heart rate variability, and the number of mistakes in a cognitive task were associated with the strength of their BOI in the uncomfortable posture: greater heart rate, lower heart rate variability and more mistakes were associated with higher levels of the BOI. These findings point in a consistent direction—that the BOI over a body that is in an uncomfortable posture can lead to subjective, physiological and cognitive effects consistent with discomfort that do not occur with the BOI over a body in a comfortable posture. PMID:26828365

  2. Remote monitoring of soldier safety through body posture identification using wearable sensor networks

    NASA Astrophysics Data System (ADS)

    Biswas, Subir; Quwaider, Muhannad

    2008-04-01

    The physical safety and well being of the soldiers in a battlefield is the highest priority of Incident Commanders. Currently, the ability to track and monitor soldiers rely on visual and verbal communication which can be somewhat limited in scenarios where the soldiers are deployed inside buildings and enclosed areas that are out of visual range of the commanders. Also, the need for being stealth can often prevent a battling soldier to send verbal clues to a commander about his or her physical well being. Sensor technologies can remotely provide various data about the soldiers including physiological monitoring and personal alert safety system functionality. This paper presents a networked sensing solution in which a body area wireless network of multi-modal sensors can monitor the body movement and other physiological parameters for statistical identification of a soldier's body posture, which can then be indicative of the physical conditions and safety alerts of the soldier in question. The specific concept is to leverage on-body proximity sensing and a Hidden Markov Model (HMM) based mechanism that can be applied for stochastic identification of human body postures using a wearable sensor network. The key idea is to collect relative proximity information between wireless sensors that are strategically placed over a subject's body to monitor the relative movements of the body segments, and then to process that using HMM in order to identify the subject's body postures. The key novelty of this approach is a departure from the traditional accelerometry based approaches in which the individual body segment movements, rather than their relative proximity, is used for activity monitoring and posture detection. Through experiments with body mounted sensors we demonstrate that while the accelerometry based approaches can be used for differentiating activity intensive postures such as walking and running, they are not very effective for identification and

  3. Evaluation of postural stability in children with hemiplegic cerebral palsy

    PubMed Central

    Kenis-Coskun, Ozge; Giray, Esra; Eren, Beyhan; Ozkok, Ozlem; Karadag-Saygi, Evrim

    2016-01-01

    [Purpose] Postural stability is the ability of to maintain the position of the body within the support area. This function is affected in cerebral palsy. The aim of the present study was to compare static and dynamic postural stability between children with hemiplegic cerebral palsy and healthy controls. [Subjects and Methods] Thirty-seven children between the ages of 5 and 14 diagnosed with hemiplegic cerebral palsy (19 right, 18 left) and 23 healthy gender- and age-matched controls were included in the study. Postural stability was evaluated in both of the groups using a Neurocom Balance. Sway velocity was measured both with the eyes open and closed. Sit to stand and turning abilities were also assessed. [Results] The sway velocities with the eyes open and closed were significantly different between the groups. The weight transfer time in the Sit to Stand test was also significantly slower in children with cerebral palsy. Children with cerebral palsy also showed slower turning times and greater sway velocities during the Step and Quick Turn test on a force plate compared with their healthy counterparts. [Conclusion] Both static and dynamic postural stability parameters are affected in hemiplegic cerebral palsy. Further research is needed to define rehabilitation interventions to improve these parameters in patients. PMID:27313338

  4. Evaluation of postural stability in children with hemiplegic cerebral palsy.

    PubMed

    Kenis-Coskun, Ozge; Giray, Esra; Eren, Beyhan; Ozkok, Ozlem; Karadag-Saygi, Evrim

    2016-05-01

    [Purpose] Postural stability is the ability of to maintain the position of the body within the support area. This function is affected in cerebral palsy. The aim of the present study was to compare static and dynamic postural stability between children with hemiplegic cerebral palsy and healthy controls. [Subjects and Methods] Thirty-seven children between the ages of 5 and 14 diagnosed with hemiplegic cerebral palsy (19 right, 18 left) and 23 healthy gender- and age-matched controls were included in the study. Postural stability was evaluated in both of the groups using a Neurocom Balance. Sway velocity was measured both with the eyes open and closed. Sit to stand and turning abilities were also assessed. [Results] The sway velocities with the eyes open and closed were significantly different between the groups. The weight transfer time in the Sit to Stand test was also significantly slower in children with cerebral palsy. Children with cerebral palsy also showed slower turning times and greater sway velocities during the Step and Quick Turn test on a force plate compared with their healthy counterparts. [Conclusion] Both static and dynamic postural stability parameters are affected in hemiplegic cerebral palsy. Further research is needed to define rehabilitation interventions to improve these parameters in patients.

  5. Body posture recognition and turning recording system for the care of bed bound patients.

    PubMed

    Hsiao, Rong-Shue; Mi, Zhenqiang; Yang, Bo-Ru; Kau, Lih-Jen; Bitew, Mekuanint Agegnehu; Li, Tzu-Yu

    2015-01-01

    This paper proposes body posture recognition and turning recording system for assisting the care of bed bound patients in nursing homes. The system continuously detects the patient's body posture and records the length of time for each body posture. If the patient remains in the same body posture long enough to develop pressure ulcers, the system notifies caregivers to change the patient's body posture. The objective of recording is to provide the log of body turning for querying of patients' family members. In order to accurately detect patient's body posture, we developed a novel pressure sensing pad which contains force sensing resistor sensors. Based on the proposed pressure sensing pad, we developed a bed posture recognition module which includes a bed posture recognition algorithm. The algorithm is based on fuzzy theory. The body posture recognition algorithm can detect the patient's bed posture whether it is right lateral decubitus, left lateral decubitus, or supine. The detected information of patient's body posture can be then transmitted to the server of healthcare center by the communication module to perform the functions of recording and notification. Experimental results showed that the average posture recognition accuracy for our proposed module is 92%. PMID:26444814

  6. Intricate Correlation between Body Posture, Personality Trait and Incidence of Body Pain: A Cross-Referential Study Report

    PubMed Central

    Guimond, Sylvain; Massrieh, Wael

    2012-01-01

    Objective Occupational back pain is a disorder that commonly affects the working population, resulting in disability, health-care utilization, and a heavy socioeconomic burden. Although the etiology of occupational pain remains largely unsolved, anecdotal evidence exists for the contribution of personality and posture to long-term pain management, pointing to a direct contribution of the mind-body axis. In the current study, we have conducted an extensive evaluation into the relationships between posture and personality. Method We have sampled a random population of 100 subjects (50 men and 50 women) in the age range of 13–82 years based on their personality and biomechanical profiles. All subjects were French-Canadian, living in Canada between the Québec and Sorel-Tracy areas. The Biotonix analyses and report were used on the subjects being tested in order to distinguish postural deviations. Personality was determined by using the Myers-Briggs Type Indicator questionnaire. Results We establish a correlation between ideal and kyphosis-lordosis postures and extraverted personalities. Conversely, our studies establish a correlative relationship between flat back and sway-back postures with introverted personalities. Conclusion Overall, our studies establish a novel correlative relationship between personality, posture and pain. PMID:22624034

  7. Modeling On-Body DTN Packet Routing Delay in the Presence of Postural Disconnections

    PubMed Central

    Quwaider, Muhannad; Taghizadeh, Mahmoud; Biswas, Subir

    2014-01-01

    This paper presents a stochastic modeling framework for store-and-forward packet routing in Wireless Body Area Networks (WBAN) with postural partitioning. A prototype WBANs has been constructed for experimentally characterizing and capturing on-body topology disconnections in the presence of ultrashort range radio links, unpredictable RF attenuation, and human postural mobility. Delay modeling techniques for evaluating single-copy on-body DTN routing protocols are then developed. End-to-end routing delay for a series of protocols including opportunistic, randomized, and two other mechanisms that capture multiscale topological localities in human postural movements have been evaluated. Performance of the analyzed protocols are then evaluated experimentally and via simulation to compare with the results obtained from the developed model. Finally, a mechanism for evaluating the topological importance of individual on-body sensor nodes is developed. It is shown that such information can be used for selectively reducing the on-body sensor-count without substantially sacrificing the packet delivery delay. PMID:25530749

  8. Gravity and observer's body orientation influence the visual perception of human body postures.

    PubMed

    Lopez, Christophe; Bachofner, Christelle; Mercier, Manuel; Blanke, Olaf

    2009-05-04

    Since human behavior and perception have evolved within the Earth's gravitational field, humans possess an internal model of gravity. Although gravity is known to influence the visual perception of moving objects, the evidence is less clear concerning the visual perception of static objects. We investigated whether a visual judgment of the stability of human body postures (static postures of a human standing on a platform and tilted in the roll plane) may also be influenced by gravity and by the participant's orientation. Pictures of human body postures were presented in different orientations with respect to gravity and the participant's body. The participant's body was aligned to gravity (upright) or not (lying on one side). Participants performed stability judgments with respect to the platform, imagining that gravity operates in the direction indicated by the platform (that was or was not concordant with physical gravity). Such visual judgments were influenced by the picture's orientation with respect to physical gravity. When pictures were tilted by 90 degrees with respect to physical gravity, the human postures that were tilted toward physical gravity (down) were perceived as more unstable than similar postures tilted away from physical gravity (up). Stability judgments were also influenced by the picture's orientation with respect to the participant's body. This indicates that gravity and the participant's body position may influence the visual perception of static objects.

  9. Attentional biases using the body in the crowd task: are angry body postures detected more rapidly?

    PubMed

    Gilbert, Tracy; Martin, Rachael; Coulson, Mark

    2011-06-01

    Research using schematic faces has consistently demonstrated attentional biases towards threatening information (angry faces), which are accentuated for individuals with higher levels of anxiety. However, research has yet to reveal whether this is the case for other nonverbal channels of communication. In the research reported here, ninety-five undergraduates completed a body in the crowd task analogous to the face in the crowd task, to examine whether attentional biases for threat existed for schematic body postures. Participants demonstrated faster detection of threat. A discrepant angry posture in a neutral crowd was identified quicker than a discrepant happy posture in a neutral crowd. This effect was pronounced for individuals with higher self-reported levels of trait anxiety. Results also demonstrated evidence of delayed disengagement from threat. Individuals were slower (i.e., more distracted) by identical crowds of angry postures rather than happy or neutral crowds and were slower to detect a discrepant neutral posture among an angry crowd than neutral among a happy crowd. These findings are the first to establish threat biases using body postures in a visual search paradigm. The results are in accordance with previous research using schematic face stimuli. Theoretical and practical implications are discussed.

  10. Reduction mammoplasty improves body posture and decreases the perception of pain.

    PubMed

    Goulart, Remi; Detanico, Daniele; Vasconcellos, Roberta Pires; Schütz, Gustavo Ricardo; Dos Santos, Saray Giovana

    2013-01-01

    Women with hypertrophic breasts often experience body pain and posture problems, which tend to be reduced or even eliminated after reduction mammoplasty. The present study aimed to analyze the effects of reduction mammoplasty on anthropometric variables, body posture and pain in women with breast hypertrophy. Eleven women (mean [± SD] age 31.3±10.4 years) participated in the present study. Anthropometric variables, body posture and pain perception were evaluated pretest, and 60 (post60) and 90 (post90) days after reduction mammoplasty. Commercially available posture analysis software was used to analyze the following variables: acromial horizontal alignment (AHA), angle between acromial and anterior superior iliac spines (A-AAIS), vertical alignment of right (R) and left (L) trunk (VAT), vertical alignment of R and L body (VAB) and horizontal alignment of R and L pelvis (HAP). Descriptive statistics and ANOVA for repeated measures were used, and effect sizes (ES) were measured; the level of significance was set at P<0.05. There were no significant differences in anthropometric variables among the assessments. Only HAP-R showed a significant decrease; however, when analyzed, ES, VAT- L and HAP- L in post60, and VAT-R, VAT-L, HAP-R, HAP-L and VAB-L in post90 showed large ES after mammoplasty (ES>0.70). There were significant reductions in pain at post60 and post90 in the neck, cervical spine, back, shoulder and arm (P<0.05). Following mammoplasty, an improvement in body posture, primarily in the alignment of shoulders, trunk and pelvis, and a decrease in pain in the upper limbs and spine, were observed.

  11. Modeling of a seated human body exposed to vertical vibrations in various automotive postures.

    PubMed

    Liang, Cho-Chung; Chiang, Chi-Feng

    2008-04-01

    Although much research has been devoted to constructing specific models or to measuring the response characteristics of seated subjects, investigations on a mathematical human model on a seat with a backrest to evaluate vehicular riding comfort have not yet attracted the same level of attention. For the responses of a seated body to vertical vibrations, mathematical models of the mechanisms must be at least two-dimensional in the sagittal plane. In describing the motions of a seated body, two multibody models representative of the automotive postures found in the literature were investigated, one with and the other without a backrest support. Both models were modified to suitably represent the different automotive postures with and without backrest supports, and validated by various experimental data from the published literature pertaining to the same postural conditions. On the basis of the analytical study and the experimental validation, the fourteen-degrees-of-freedom model proposed in this research was found to be best fitted to the test results; therefore, this model is recommended for studying the biodynamic responses of a seated human body exposed to vertical vibrations in various automotive postures.

  12. Trait Dominance Promotes Reflexive Staring at Masked Angry Body Postures

    PubMed Central

    Hortensius, Ruud; van Honk, Jack; de Gelder, Beatrice; Terburg, David

    2014-01-01

    It has been shown that dominant individuals sustain eye-contact when non-consciously confronted with angry faces, suggesting reflexive mechanisms underlying dominance behaviors. However, dominance and submission can be conveyed and provoked by means of not only facial but also bodily features. So far few studies have investigated the interplay of body postures with personality traits and behavior, despite the biological relevance and ecological validity of these postures. Here we investigate whether non-conscious exposure to bodily expressions of anger evokes reflex-like dominance behavior. In an interactive eye-tracking experiment thirty-two participants completed three social dominance tasks with angry, happy and neutral facial, bodily and face and body compound expressions that were masked from consciousness. We confirmed our predictions of slower gaze-aversion from both non-conscious bodily and compound expressions of anger compared to happiness in high dominant individuals. Results from a follow-up experiment suggest that the dominance behavior triggered by exposure to bodily anger occurs with basic detection of the category, but not recognition of the emotional content. Together these results suggest that dominant staring behavior is reflexively driven by non-conscious perception of the emotional content and triggered by not only facial but also bodily expression of anger. PMID:25549321

  13. Effects of the removal of vision on body sway during different postures in elite gymnasts.

    PubMed

    Asseman, F; Caron, O; Crémieux, J

    2005-03-01

    The aim of this study was to analyse the effects of the removal of vision on postural performance and postural control in function of the difficulty and specificity of the posture. Twelve elite gymnasts were instructed to be as stable as possible with eyes open and eyes closed in three postures: bipedal, unipedal, and handstand ranked from the less difficult and less specific to the more difficult and more specific. The ratios eyes closed on eyes open, computed on CP surface and CP mean velocity, which respectively represents postural performance and postural control, were similar in the bipedal and handstand postures. They were highly increased in the unipedal one. The effect of the removal of vision and so the role of vision on body sway was not directly linked to the difficulty or specificity of the posture; other tasks' characteristics like the segments configuration also played a role. PMID:15726495

  14. Postural Assessment of Students Evaluating the Need of Ergonomic Seat and Magnification in Dentistry.

    PubMed

    Dable, Rajani A; Wasnik, Pradnya B; Yeshwante, Babita J; Musani, Smita I; Patil, Ashishkumar K; Nagmode, Sunilkumar N

    2014-12-01

    Dental students using conventional chairs need immediate change in their posture. Implementing an ergonomic posture is necessary as they are at high risk for developing musculoskeletal disorders. This study recommends the use of an ergonomic seat and magnification system to enhance the visibility and the posture of an operator. The aim of this study is to make a foray into the hazards caused by inappropriate posture of dental students while working. It also aims at creating a cognizance about the related health implications among the dental fraternity at large, and to understand the significance of adopting an ergonomic posture since the beginning of the professional course. In the present study, postures have been assessed by using rapid upper limb assessment (RULA). This method uses diagrams of body postures and three scoring tables to evaluate ones exposure to risk factors. Ninety students from II BDS (preclinical students in the second year of dental school) were assessed in three groups using three different seats with and without magnification system. The results recorded significantly higher RULA scores for the conventional seats without using the magnification system compared to the SSC (Salli Saddle Chair-an ergonomic seat) with the use of magnification system. A poor ergonomic posture can make the dental students get habituated to the wrong working style which might lead to MSDs (Musculoskeletal diseases). It is advisable to acclimatize to good habits at the inception of the course, to prevent MSDs later in life. PMID:26199492

  15. Modelling resonances of the standing body exposed to vertical whole-body vibration: Effects of posture

    NASA Astrophysics Data System (ADS)

    Subashi, G. H. M. J.; Matsumoto, Y.; Griffin, M. J.

    2008-10-01

    Lumped parameter mathematical models representing anatomical parts of the human body have been developed to represent body motions associated with resonances of the vertical apparent mass and the fore-and-aft cross-axis apparent mass of the human body standing in five different postures: 'upright', 'lordotic', 'anterior lean', 'knees bent', and 'knees more bent'. The inertial and geometric parameters of the models were determined from published anthropometric data. Stiffness and damping parameters were obtained by comparing model responses with experimental data obtained previously. The principal resonance of the vertical apparent mass, and the first peak in the fore-and-aft cross-axis apparent mass, of the standing body in an upright posture (at 5-6 Hz) corresponded to vertical motion of the viscera in phase with the vertical motion of the entire body due to deformation of the tissues at the soles of the feet, with pitch motion of the pelvis out of phase with pitch motion of the upper body above the pelvis. Upward motion of the body was in phase with the forward pitch motion of the pelvis. Changing the posture of the upper body had minor effects on the mode associated with the principal resonances of the apparent mass and cross-axis apparent mass, but the mode changed significantly with bending of the legs. In legs-bent postures, the principal resonance (at about 3 Hz) was attributed to bending of the legs coupled with pitch motion of the pelvis in phase with pitch motion of the upper body. In this mode, extension of the legs was in phase with the forward pitch motion of the upper body and the upward vertical motion of the viscera.

  16. Postural effects on intracranial pressure: modeling and clinical evaluation.

    PubMed

    Qvarlander, Sara; Sundström, Nina; Malm, Jan; Eklund, Anders

    2013-11-01

    The physiological effect of posture on intracranial pressure (ICP) is not well described. This study defined and evaluated three mathematical models describing the postural effects on ICP, designed to predict ICP at different head-up tilt angles from the supine ICP value. Model I was based on a hydrostatic indifference point for the cerebrospinal fluid (CSF) system, i.e., the existence of a point in the system where pressure is independent of body position. Models II and III were based on Davson's equation for CSF absorption, which relates ICP to venous pressure, and postulated that gravitational effects within the venous system are transferred to the CSF system. Model II assumed a fully communicating venous system, and model III assumed that collapse of the jugular veins at higher tilt angles creates two separate hydrostatic compartments. Evaluation of the models was based on ICP measurements at seven tilt angles (0-71°) in 27 normal pressure hydrocephalus patients. ICP decreased with tilt angle (ANOVA: P < 0.01). The reduction was well predicted by model III (ANOVA lack-of-fit: P = 0.65), which showed excellent fit against measured ICP. Neither model I nor II adequately described the reduction in ICP (ANOVA lack-of-fit: P < 0.01). Postural changes in ICP could not be predicted based on the currently accepted theory of a hydrostatic indifference point for the CSF system, but a new model combining Davson's equation for CSF absorption and hydrostatic gradients in a collapsible venous system performed well and can be useful in future research on gravity and CSF physiology.

  17. Perceived body discomfort and trunk muscle activity in three prolonged sitting postures

    PubMed Central

    Waongenngarm, Pooriput; Rajaratnam, Bala S.; Janwantanakul, Prawit

    2015-01-01

    [Purpose] This study aimed to investigate the perceived discomfort and trunk muscle activity in three different 1-hour sitting postures. [Subjects] A repeated-measures design study was conducted on 10 healthy subjects. [Methods] Each subject sat for an hour in three sitting postures (i.e., upright, slumped, and forward leaning sitting postures). Subjects rated perceived body discomfort using Borg’s CR-10 scale at the beginning and after 1 hour sitting. The electromyographic activity of the trunk muscle activity was recorded during the 1-hour period of sitting. [Results] The forward leaning sitting posture led to higher Borg scores in the low back than those in the upright (p = 0.002) and slumped sitting postures (p < 0.001). The forward leaning posture was significantly associated with increased iliocostalis lumborum pars thoracis (ICL) and superficial lumbar multifidus (MF) muscle activity compared with the upright and slumped sitting postures. The upright sitting posture was significantly associated with increased internal oblique (IO)/transversus abdominis (TrA) and ICL muscle activity compared with the slumped sitting posture. [Conclusion] The sitting posture with the highest low back discomfort after prolonged sitting was the forward leaning posture. Sitting in an upright posture is recommended because it increases IO/TrA muscle activation and induces only relatively moderate ICL and MF muscle activation. PMID:26311951

  18. The addition of body armor diminishes dynamic postural stability in military soldiers.

    PubMed

    Sell, Timothy C; Pederson, Jonathan J; Abt, John P; Nagai, Takashi; Deluzio, Jennifer; Wirt, Michael D; McCord, Larry J; Lephart, Scott M

    2013-01-01

    Poor postural stability has been identified as a risk factor for lower extremity musculoskeletal injury. The additional weight of body armor carried by Soldiers alters static postural stability and may predispose Soldiers to lower extremity musculoskeletal injuries. However, static postural stability tasks poorly replicate the dynamic military environment, which places considerable stress on the postural control system during tactical training and combat. Therefore, the purpose of this study was to examine the effects of body armor on dynamic postural stability during single-leg jump landings. Thirty-six 101st Airborne Division (Air Assault) Soldiers performed single-leg jump landings in the anterior direction with and without wearing body armor. The dynamic postural stability index and the individual stability indices (medial-lateral stability index, anterior-posterior stability index, and vertical stability index) were calculated for each condition. Paired sample t-tests were performed to determine differences between conditions. Significant differences existed for the medial-lateral stability index, anterior-posterior stability index, vertical stability index, and dynamic postural stability index (p < 0.05). The addition of body armor resulted in diminished dynamic postural stability, which may result in increased lower extremity injuries. Training programs should address the altered dynamic postural stability while wearing body armor in attempts to promote adaptations that will result in safer performance during dynamic tasks.

  19. Holding a Handle for Balance during Continuous Postural Perturbations—Immediate and Transitionary Effects on Whole Body Posture

    PubMed Central

    Čamernik, Jernej; Potocanac, Zrinka; Peternel, Luka; Babič, Jan

    2016-01-01

    When balance is exposed to perturbations, hand contacts are often used to assist postural control. We investigated the immediate and the transitionary effects of supportive hand contacts during continuous anteroposterior perturbations of stance by automated waist-pulls. Ten young adults were perturbed for 5 min and required to maintain balance by holding to a stationary, shoulder-high handle and following its removal. Center of pressure (COP) displacement, hip, knee and ankle angles, leg and trunk muscle activity and handle contact forces were acquired. The analysis of results show that COP excursions are significantly smaller when the subjects utilize supportive hand contact and that the displacement of COP is strongly correlated to the perturbation force and significantly larger in the anterior than posterior direction. Regression analysis of hand forces revealed that subjects utilized the hand support significantly more during the posterior than anterior perturbations. Moreover, kinematical analysis showed that utilization of supportive hand contacts alter posture of the whole body and that postural readjustments after the release of the handle, occur at different time scales in the hip, knee and ankle joints. Overall, our findings show that supportive hand contacts are efficiently used for balance control during continuous postural perturbations and that utilization of a handle has significant immediate and transitionary effects on whole body posture. PMID:27725798

  20. The influence of body posture on the kinematics of prehension in humans and gorillas (Gorilla gorilla).

    PubMed

    Reghem, E; Chèze, L; Coppens, Y; Pouydebat, E

    2014-03-01

    Much of our current understanding of human prehension in a comparative context is based on macaque models in a sitting, constrained body posture. In a previous study, we clearly showed differences in the amplitude of the forelimb joints between five primate species (lemur, capuchin, chimpanzee, gorilla and human) during unconstrained grasping where the animals were free to choose their body posture. One of our interrogations was to know if these differences could be due to the body posture. To address this question, this study compares humans with new data for gorillas during an unconstrained food prehension task in two body postures, a sitting and a quadrupedal one. The objective is to determine the behavioral and kinematic strategies (amplitudes and patterns of evolution of the articular angles) as well as differences and invariants of trunk and forelimb motions between species. The subjects were recorded by five cameras, and landmarks were digitized frame by frame to reconstruct 3D movement. Our results show that (1) despite significant influences of body postures on ranges of motion in gorillas and humans, species preserve their specific forelimb joint and trunk contribution; (2) body posture has a limited effect on the basic pattern of wrist velocity. Our study indicates that different primate species have specific kinematic features of limb coordination during prehension, which dose not alter with changes in posture. Therefore, across varying species, it is possible to compare limb kinematics irrespective of postural constraints and unconstrained condition need to be explored in other primates to understand the evolution of primate prehension.

  1. Ergonomic evaluation of postural stress in school workshop.

    PubMed

    Hashim, Adila Md; Dawal, Siti Zawiahmd Md; Yusoff, Nukman

    2012-01-01

    The objective of this study is to compare the evaluation of postural analysis between a self-report questionnaire and physical assessments methods for students aged 13 to 15 years old in school workshop. 336 students were volunteered as participants to fill in the questionnaire and being observed in the workshop. Total of 104 positions were selected and analyzed while students performing their tasks. Questionnaire data was examined to specify the prevalence of postural stress symptoms. The relationship of postural stress by physical assessment methods (RULA and REBA methods) was defined to identify the risk level of students' working posture. From the results, comparison of four factors categorized from total of 22 questions among ages, the mean values were lower for 13 years old students meaning that they were faced higher posture problems while using the workstation. The obtained results from both physical assessment methods and questionnaire analysis have identified 13 years old students faced higher risk exposure. Analysis results emphasized the fact that self-reports questionnaire method has almost accurate as postural evaluation methods to identify physical risks in workplace. The result also shows that an intervention is needed to overcome the posture problems. PMID:22316824

  2. Dynamic Postural Control in Female Athletes and Nonathletes After a Whole-Body Fatigue Protocol.

    PubMed

    Baghbani, Fatemeh; Woodhouse, Linda J; Gaeini, Abbas A

    2016-07-01

    Baghbani, F, Woodhouse, LJ, and Gaeini, AA. Dynamic postural control in female athletes and nonathletes after a whole-body fatigue protocol. J Strength Cond Res 30(7): 1942-1947, 2016-Postural control is a crucial element in regular training of athletes, development of complex technical movement, and injury prevention; however, distributing factor of the postural control such as fatigue has been neglected by athletic trainers in novice and inexperienced athletes. The objective of this study was to compare changes in dynamic postural control of young female athletes and nonathletes after a fatigue protocol. Thirty females (15 athletes and 15 nonathletes) with no orthopedic problems were recruited to participate in this study. All participants completed the pre-SEBT (star excursion balance test) in 8 directions at baseline; then, they performed a 20-minute fatigue protocol after which post-SEBT was measured. Rating of perceived exertion was measured using the Borg scale immediately before, mid-way through (i.e., after the third station), and after performing the fatigue protocol (i.e., immediately before the post-SEBT). Female nonathlete groups had significant differences in dynamic balance performance after fatigue in the medial, posteromedial, and posterior directions (p < 0.01) measured by SEBT. Athletes, however, showed no significant changes after the fatigue protocol. Our results indicates the importance of evaluation and monitoring of dynamic postural control of the novice with progressing the exercise time. Our findings could also help coaches to develop trainings focused on the 3 directions of medial, posteromedial, and posterior directions and aimed at exercises increasing fatigue resistance.

  3. Viewing Pain and Happy Faces Elicited Similar Changes in Postural Body Sway

    PubMed Central

    Gea, Juan; Muñoz, Miguel A.; Costa, Isis; Ciria, Luís F.; Miranda, José G. V.; Montoya, Pedro

    2014-01-01

    Affective facial expressions are potent social cues that can induce relevant physiological changes, as well as behavioral dispositions in the observer. Previous studies have revealed that angry faces induced significant reductions in body sway as compared with neutral and happy faces, reflecting an avoidance behavioral tendency as freezing. The expression of pain is usually considered an unpleasant stimulus, but also a relevant cue for delivering effective care and social support. Nevertheless, there are few data about behavioral dispositions elicited by the observation of pain expressions in others. The aim of the present research was to evaluate approach–avoidance tendencies by using video recordings of postural body sway when participants were standing and observing facial expressions of pain, happy and neutral. We hypothesized that although pain faces would be rated as more unpleasant than the other faces, they would provoke significant changes in postural body sway as compared to neutral facial expressions. Forty healthy female volunteers (mean age 25) participated in the study. Amplitude of forward movements and backward movements in the anterior-posterior and medial-lateral axes were obtained. Statistical analyses revealed that pain faces were the most unpleasant stimuli, and that both happy and pain faces were more arousing than neutral ones. Happy and pain faces also elicited greater amplitude of body sway in the anterior-posterior axes as compared with neutral faces. In addition, significant positive correlations were found between body sway elicited by pain faces and pleasantness and empathic ratings, suggesting that changes in postural body sway elicited by pain faces might be associated with approach and cooperative behavioral responses. PMID:25093727

  4. Inter-worker variability in lower body postures during assembly line work: implications for exposure assessment.

    PubMed

    Keyserling, W Monroe; Wiggermann, Neal; Werner, Robert A; Gell, Nancy

    2010-05-01

    This study evaluated inter-worker variability in lower body posture and work activity during highly-structured assembly line work. Data were collected from 79 unique assembly line workstations in an engine manufacturing plant. Because the plant utilized work teams, 4-8 workers rotated through each workstation. At least 30 min of videotape was collected from at least three workers at each workstation. A computer-assisted work sampling procedure randomly selected 200 video "freeze-frames" for each worker. Lower body posture/movement (e.g., sit, stand, walk, etc.) was determined for each frame and used to estimate the percentage of time the worker spent in various postures and activities. Chi-square analyses were performed for each workstation to assess the significance of inter-worker differences. Due to variations in individual work methods, significant differences (p <.05) were found at 57 out of 79 workstations (72%). The greatest differences occurred when workers had the option to choose between standing and sitting (significant in 8 of 8 cases; in extreme examples, sit time ranged between 0-100% on one job, and 6.5-98% on another). Studying a single worker (or "proxy") can contribute to substantial error when estimating exposures in workplace studies of ergonomic stressors, since the proxy may not be representative of all workers who perform the job. Individual measurements are preferable, particularly for jobs where workers have substantial latitude to develop individualized work methods.

  5. The personification of animals: coding of human and nonhuman body parts based on posture and function.

    PubMed

    Welsh, Timothy N; McDougall, Laura; Paulson, Stephanie

    2014-09-01

    The purpose of the present research was to determine how humans represent the bodies and limbs of nonhuman mammals based on anatomical and functional properties. To this end, participants completed a series of body-part compatibility tasks in which they responded with a thumb or foot response to the color of a stimulus (red or blue, respectively) presented on different limbs of several animals. Across the studies, this compatibility task was conducted with images of human and nonhuman animals (bears, cows, and monkeys) in bipedal or quadrupedal postures. The results revealed that the coding of the limbs of nonhuman animals is strongly influenced by the posture of the body, but not the functional capacity of the limb. Specifically, body-part compatibility effects were present for both human and nonhuman animals when the figures were in a bipedal posture, but were not present when the animals were in a quadrupedal stance (Experiments 1a-c). Experiments 2a and 2b revealed that the posture-based body-part compatibility effects were not simply a vertical spatial compatibility effect or due to a mismatch between the posture of the body in the image and the participant. These data indicate that nonhuman animals in a bipedal posture are coded with respect to the "human" body representation, whereas nonhuman animals in a quadrupedal posture are not mapped to the human body representation. Overall, these studies provide new insight into the processes through which humans understand, mimic, and learn from the actions of nonhuman animals.

  6. Use of Video Analysis System for Working Posture Evaluations

    NASA Technical Reports Server (NTRS)

    McKay, Timothy D.; Whitmore, Mihriban

    1994-01-01

    In a work environment, it is important to identify and quantify the relationship among work activities, working posture, and workplace design. Working posture may impact the physical comfort and well-being of individuals, as well as performance. The Posture Video Analysis Tool (PVAT) is an interactive menu and button driven software prototype written in Supercard (trademark). Human Factors analysts are provided with a predefined set of options typically associated with postural assessments and human performance issues. Once options have been selected, the program is used to evaluate working posture and dynamic tasks from video footage. PVAT has been used to evaluate postures from Orbiter missions, as well as from experimental testing of prototype glove box designs. PVAT can be used for video analysis in a number of industries, with little or no modification. It can contribute to various aspects of workplace design such as training, task allocations, procedural analyses, and hardware usability evaluations. The major advantage of the video analysis approach is the ability to gather data, non-intrusively, in restricted-access environments, such as emergency and operation rooms, contaminated areas, and control rooms. Video analysis also provides the opportunity to conduct preliminary evaluations of existing work areas.

  7. A Method for Quantitative Evaluation of the Results of Postural Tests.

    PubMed

    Alifirova, V M; Brazovskii, K S; Zhukova, I A; Pekker, Ya S; Tolmachev, I V; Fokin, V A

    2016-07-01

    A method for quantitative evaluation of the results of postural tests is proposed. The method is based on contact-free measurements of 3D coordinates of body point movements. The result can serve as an integral test based on the Mahalanobis distance. PMID:27492397

  8. An Evaluation of the Effectiveness of an Automated Observation and Feedback System on Safe Sitting Postures

    ERIC Educational Resources Information Center

    Yu, Eunjeong; Moon, Kwangsu; Oah, Shezeen; Lee, Yohaeng

    2013-01-01

    This study evaluated the effectiveness of an automated observation and feedback system in improving safe sitting postures. Participants were four office workers. The dependent variables were the percentages of time participants spent in five safe body positions during experimental sessions. We used a multiple-baseline design counterbalanced across…

  9. The Contribution of Pre-impact Spine Posture on Human Body Model Response in Whole-body Side Impact.

    PubMed

    Poulard, David; Subit, Damien; Donlon, John-Paul; Lessley, David J; Kim, Taewung; Park, Gwansik; Kent, Richard W

    2014-11-01

    The objective of the study was to analyze independently the contribution of pre-impact spine posture on impact response by subjecting a finite element human body model (HBM) to whole-body, lateral impacts. Seven postured models were created from the original HBM: one matching the standard driving posture and six matching pre-impact posture measured for each of six subjects tested in previously published experiments. The same measurements as those obtained during the experiments were calculated from the simulations, and biofidelity metrics based on signals correlation were established to compare the response of HBM to that of the cadavers. HBM responses showed good correlation with the subject response for the reaction forces, the rib strain (correlation score=0.8) and the overall kinematics. The pre-impact posture was found to greatly alter the reaction forces, deflections and the strain time histories mainly in terms of time delay. By modifying only the posture of HBM, the variability in the impact response was found to be equivalent to that observed in the experiments performed with cadavers with different anthropometries. The patterns observed in the responses of the postured HBM indicate that the inclination of the spine in the frontal plane plays a major role. The postured HBM sustained from 2 to 5 bone fractures, including the scapula in some cases, confirming that the pre-impact posture influences the injury outcome predicted by the simulation.

  10. A dance to the music of time: aesthetically-relevant changes in body posture in performing art.

    PubMed

    Daprati, Elena; Iosa, Marco; Haggard, Patrick

    2009-01-01

    In performing arts, body postures are both means for expressing an artist's intentions, and also artistic objects, appealing to the audience. The postures of classical ballet obey the body's biomechanical limits, but also follow strict rules established by tradition. This combination offers a perfect milieu for assessing scientifically how the execution of this particular artistic activity has changed over time, and evaluating what factors may induce such changes. We quantified angles between body segments in archive material showing dancers from a leading company over a 60-year period. The data showed that body positions supposedly fixed by codified choreography were in fact implemented by very different elevation angles, according to the year of ballet production. Progressive changes lead to increasingly vertical positions of the dancer's body over the period studied. Experimental data showed that these change reflected aesthetic choices of naïve modern observers. Even when reduced to stick figures and unrecognisable shapes, the more vertical postures drawn from later productions were systematically preferred to less vertical postures from earlier productions. This gradual change within a conservative art form provides scientific evidence that aesthetic change may arise from continuous interaction between artistic tradition, individual artists' creativity, and a wider environmental context. This context may include social aesthetic pressure from audiences. PMID:19325705

  11. Evidence for impaired verbal identification but intact nonverbal recognition of fearful body postures in Asperger's syndrome.

    PubMed

    Doody, John P; Bull, Peter

    2013-07-01

    While most studies of emotion recognition in Asperger's Syndrome (AS) have focused solely on the verbal decoding of affective states, the current research employed the novel technique of using both nonverbal matching and verbal labeling tasks to examine the decoding of emotional body postures and facial expressions. AS participants performed as accurately as controls at matching fear body postures, but were significantly less accurate than controls verbally identifying these same stimuli. This profile arguably indicates that that while the AS participants were aware that the fear body posture stimuli represented a distinct emotion, they were unsure as to which specific emotion. In addition, the AS participants took significantly longer than the controls to respond to anger body posture stimuli on a matching task. However, in contrast to previous studies, AS and control participants did not differ significantly in their responses to facial expression stimuli, in terms of either accuracy or response times.

  12. Evidence for impaired verbal identification but intact nonverbal recognition of fearful body postures in Asperger's syndrome.

    PubMed

    Doody, John P; Bull, Peter

    2013-07-01

    While most studies of emotion recognition in Asperger's Syndrome (AS) have focused solely on the verbal decoding of affective states, the current research employed the novel technique of using both nonverbal matching and verbal labeling tasks to examine the decoding of emotional body postures and facial expressions. AS participants performed as accurately as controls at matching fear body postures, but were significantly less accurate than controls verbally identifying these same stimuli. This profile arguably indicates that that while the AS participants were aware that the fear body posture stimuli represented a distinct emotion, they were unsure as to which specific emotion. In addition, the AS participants took significantly longer than the controls to respond to anger body posture stimuli on a matching task. However, in contrast to previous studies, AS and control participants did not differ significantly in their responses to facial expression stimuli, in terms of either accuracy or response times. PMID:23179341

  13. Early postural adjustments in preparation to whole-body voluntary sway

    PubMed Central

    Klous, Miriam; Mikulic, Pavle; Latash, Mark L.

    2011-01-01

    We studied postural adjustments associated with a quick voluntary postural sway under two conditions, self-paced and simple reaction-time. Standing subjects were required to produce quick discrete shifts of the center of pressure (COP) forward. About 400–500 ms prior to the instructed COP shift, there were deviations of the COP in the opposite direction (backwards) accompanied by changes in the activation levels of several postural muscles. Under the reaction-time conditions, the timing of those early postural adjustments did not change (repeated measures MANOVA: p>0.05) while its magnitude increased significantly (confirmed by repeated measures MANOVA: p<0.05). These observations are opposite to those reported for anticipatory postural adjustments under simple reaction time conditions (a significant change in the timing without major changes in the magnitude). We conclude that there are two types of feed-forward postural adjustments. Early postural adjustments prepare the body for the planned action and/or expected perturbation. Some of these preparatory actions may be mechanically necessary. Later, anticipatory postural adjustments generate net forces and moments of force acting against those associated with the expected perturbation. Both types of adjustments fit well the referent configuration hypothesis, which offers a unified view on movement-posture control. PMID:22142740

  14. Early postural adjustments in preparation to whole-body voluntary sway.

    PubMed

    Klous, Miriam; Mikulic, Pavle; Latash, Mark L

    2012-02-01

    We studied postural adjustments associated with a quick voluntary postural sway under two conditions, self-paced and simple reaction-time. Standing subjects were required to produce quick discrete shifts of the center of pressure (COP) forward. About 400-500ms prior to the instructed COP shift, there were deviations of the COP in the opposite direction (backwards) accompanied by changes in the activation levels of several postural muscles. Under the reaction-time conditions, the timing of those early postural adjustments did not change (repeated measures MANOVA: p>0.05) while its magnitude increased significantly (confirmed by repeated measures MANOVA: p<0.05). These observations are opposite to those reported for anticipatory postural adjustments under simple reaction time conditions (a significant change in the timing without major changes in the magnitude). We conclude that there are two types of feed-forward postural adjustments. Early postural adjustments prepare the body for the planned action and/or expected perturbation. Some of these preparatory actions may be mechanically necessary. Later, anticipatory postural adjustments generate net forces and moments of force acting against those associated with the expected perturbation. Both types of adjustments fit well the referent configuration hypothesis, which offers a unified view on movement-posture control. PMID:22142740

  15. Quantification of Inflight Physical Changes: Anthropometry and Neutral Body Posture (Body Measures)

    NASA Technical Reports Server (NTRS)

    Rajulu, Sudhakar; Young, Karen; Reid, Chris; Dirlich, Tom

    2014-01-01

    The goal of this study is to gather preliminary data to better understand the magnitude and variability of microgravity changes on the body. To do this, we aim to gather and document microgravity effects on body measurements. Lengths, Breadths, Depths ? Circumferences, Joint angles. To determine if/how the Neutral Body Posture (NBP) is influenced by the above factors. This will be the first time these proposed measures are collected in space. It is anticipated that body measurements will change due to microgravity and fluid shifts. This data is important so that the changes that may occur during long-duration space flight can be identified and applied to suit fit, suit sizing, workstation design, etc. for future missions in order to prevent injury and reduce crew time for altering or adjusting suits, workstations, etc.

  16. Effect of mat pilates exercise on postural alignment and body composition of middle-aged women.

    PubMed

    Lee, Hyo Taek; Oh, Hyun Ok; Han, Hui Seung; Jin, Kwang Youn; Roh, Hyo Lyun

    2016-06-01

    [Purpose] This study attempted to examine whether Pilates is an effective exercise for improving the postural alignment and health of middle-aged women. [Subjects and Methods] The participants in this study were 36 middle-aged women (20 in the experimental group, 16 in the control group). The experimental group participated in Pilates exercise sessions three times a week for 12 weeks. Body alignment and composition measurements before and after applying the Pilates exercise program were performed with a body composition analyzer and a three-dimensional scanner. [Results] Postural alignment in the sagittal and horizontal planes was enhanced in the Pilates exercise group. Trunk alignment showed correlations with body fat and muscle mass. [Conclusion] The Pilates exercises are performed symmetrically and strengthen the deep muscles. Moreover, the results showed that muscle mass was correlated with trunk postural alignment and that the proper amount of muscle is critical in maintaining trunk postural alignment.

  17. Effect of mat pilates exercise on postural alignment and body composition of middle-aged women

    PubMed Central

    Lee, Hyo Taek; Oh, Hyun Ok; Han, Hui Seung; Jin, Kwang Youn; Roh, Hyo Lyun

    2016-01-01

    [Purpose] This study attempted to examine whether Pilates is an effective exercise for improving the postural alignment and health of middle-aged women. [Subjects and Methods] The participants in this study were 36 middle-aged women (20 in the experimental group, 16 in the control group). The experimental group participated in Pilates exercise sessions three times a week for 12 weeks. Body alignment and composition measurements before and after applying the Pilates exercise program were performed with a body composition analyzer and a three-dimensional scanner. [Results] Postural alignment in the sagittal and horizontal planes was enhanced in the Pilates exercise group. Trunk alignment showed correlations with body fat and muscle mass. [Conclusion] The Pilates exercises are performed symmetrically and strengthen the deep muscles. Moreover, the results showed that muscle mass was correlated with trunk postural alignment and that the proper amount of muscle is critical in maintaining trunk postural alignment. PMID:27390396

  18. Effect of mat pilates exercise on postural alignment and body composition of middle-aged women.

    PubMed

    Lee, Hyo Taek; Oh, Hyun Ok; Han, Hui Seung; Jin, Kwang Youn; Roh, Hyo Lyun

    2016-06-01

    [Purpose] This study attempted to examine whether Pilates is an effective exercise for improving the postural alignment and health of middle-aged women. [Subjects and Methods] The participants in this study were 36 middle-aged women (20 in the experimental group, 16 in the control group). The experimental group participated in Pilates exercise sessions three times a week for 12 weeks. Body alignment and composition measurements before and after applying the Pilates exercise program were performed with a body composition analyzer and a three-dimensional scanner. [Results] Postural alignment in the sagittal and horizontal planes was enhanced in the Pilates exercise group. Trunk alignment showed correlations with body fat and muscle mass. [Conclusion] The Pilates exercises are performed symmetrically and strengthen the deep muscles. Moreover, the results showed that muscle mass was correlated with trunk postural alignment and that the proper amount of muscle is critical in maintaining trunk postural alignment. PMID:27390396

  19. The effect of alexithymia on early visual processing of emotional body postures.

    PubMed

    Borhani, Khatereh; Borgomaneri, Sara; Làdavas, Elisabetta; Bertini, Caterina

    2016-03-01

    Body postures convey emotion and motion-related information useful in social interactions. Early visual encoding of body postures, reflected by the N190 component, is modulated both by motion (i.e., postures implying motion elicit greater N190 amplitudes than static postures) and by emotion-related content (i.e., fearful postures elicit the largest N190 amplitude). At a later stage, there is a fear-related increase in attention, reflected by an early posterior negativity (EPN) (Borhani et al., 2015). Here, we tested whether difficulties in emotional processing (i.e., alexithymia) affect early and late visual processing of body postures. Low alexithymic participants showed emotional modulation of the N190, with fearful postures specifically enhancing N190 amplitude. In contrast, high alexithymic participants showed no emotional modulation of the N190. Both groups showed preserved encoding of the motion content. At a later stage, a fear-related modulation of the EPN was found for both groups, suggesting that selective attention to salient stimuli is the same in both low and high alexithymia. PMID:26762700

  20. The effect of alexithymia on early visual processing of emotional body postures.

    PubMed

    Borhani, Khatereh; Borgomaneri, Sara; Làdavas, Elisabetta; Bertini, Caterina

    2016-03-01

    Body postures convey emotion and motion-related information useful in social interactions. Early visual encoding of body postures, reflected by the N190 component, is modulated both by motion (i.e., postures implying motion elicit greater N190 amplitudes than static postures) and by emotion-related content (i.e., fearful postures elicit the largest N190 amplitude). At a later stage, there is a fear-related increase in attention, reflected by an early posterior negativity (EPN) (Borhani et al., 2015). Here, we tested whether difficulties in emotional processing (i.e., alexithymia) affect early and late visual processing of body postures. Low alexithymic participants showed emotional modulation of the N190, with fearful postures specifically enhancing N190 amplitude. In contrast, high alexithymic participants showed no emotional modulation of the N190. Both groups showed preserved encoding of the motion content. At a later stage, a fear-related modulation of the EPN was found for both groups, suggesting that selective attention to salient stimuli is the same in both low and high alexithymia.

  1. LUBA: an assessment technique for postural loading on the upper body based on joint motion discomfort and maximum holding time.

    PubMed

    Kee, D; Karwowski, W

    2001-08-01

    This paper presents a technique for postural loading on the upper body assessment (LUBA). The proposed method is based on the new experimental data for composite index of perceived discomfort (ratio values) for a set of joint motions, including the hand, arm, neck and back, and the corresponding maximum holding times in static postures. Twenty male subjects participated in the experiment designed to measure perceived joint discomforts. The free modulus technique of the magnitude estimation method was employed to obtain subjects' discomforts for varying joint motions. The developed postural classification scheme was based on the angular deviation levels from the neutral position for each joint motion. These were divided into groups with the same degree of discomforts based on the statistical analysis. Each group was assigned a numerical discomfort score relative to the perceived discomfort value of elbow flexion, which exhibited the lowest level among all joint motions investigated in this study, and, therefore, was set as a reference point. The criteria for evaluating stresses of working postures were proposed based on the four distinct action categories, in order to enable practitioners to apply appropriate corrective actions. The proposed scheme can be used for evaluating and redesigning static working postures in industry. PMID:11461037

  2. The effect of body postures on the distribution of air gap thickness and contact area

    NASA Astrophysics Data System (ADS)

    Mert, Emel; Psikuta, Agnes; Bueno, Marie-Ange; Rossi, René M.

    2016-08-01

    The heat and mass transfer in clothing is predominantly dependent on the thickness of air layer and the magnitude of contact area between the body and the garment. The air gap thickness and magnitude of the contact area can be affected by the posture of the human body. Therefore, in this study, the distribution of the air gap and the contact area were investigated for different body postures of a flexible manikin. In addition, the effect of the garment fit (regular and loose) and style (t-shirts, sweatpants, jacket and trousers) were analysed for the interaction between the body postures and the garment properties. A flexible manikin was scanned using a three-dimensional (3D) body scanning technique, and the scans were post-processed in dedicated software. The body posture had a strong effect on the air gap thickness and the contact area for regions where the garment had a certain distance from the body. Furthermore, a mathematical model was proposed to estimate the possible heat transfer coefficient for the observed air layers and their change with posture. The outcome of this study can be used to improve the design of the protective and functional garments and predict their effect on the human body.

  3. The influence of anthropometric factors on postural balance: the relationship between body composition and posturographic measurements in young adults

    PubMed Central

    Alonso, Angélica Castilho; Luna, Natália Mariana S; Mochizuki, Luis; Barbieri, Fábio; Santos, Sileno; Greve, Julia Maria D'Andréia

    2012-01-01

    OBJECTIVE: The aim of the present study was to evaluate the influence of anthropometric characteristics and gender on postural balance in adults. One hundred individuals were examined (50 males, 50 females; age range 20-40 years). METHODS: The following body composition measurements were collected (using bone densitometry measurements): fat percentage (% fat), tissue (g), fat (g), lean mass (g), bone mineral content (g), and bone mineral density (g/cm2). In addition, the following anthropometric measurements were collected: body mass (kg), height (cm), length of the trunk-cephalic region (cm), length of the lower limbs (cm) and length of the upper limbs (cm). The following indices were calculated: body mass index (kg/m2), waist-hip ratio and the support base (cm2). Also, a postural balance test was performed using posturography variables with open and closed eyes. RESULTS: The analysis revealed poor correlations between postural balance and the anthropometric variables. A multiple linear regression analysis demonstrated that the whole group (female and male) height explained 12% of the medial-lateral displacement, 10% of the speed of oscillation, and 11% of the displacement area. The length of the trunk-cephalic length explained 6% of the displacement in the anteroposterior direction. With eyes closed, the support base and height explained 18% of the medial displacement, and the lateral height explained 10% of the displacement speed and 5% of the scroll area. CONCLUSION: Measured using posturography, the postural balance was only slightly influenced by the anthropometric variables, both with open and closed eyes. Height was the anthropometric variable that most influenced postural balance, both in the whole group and separately for each gender. Postural balance was more influenced by anthropometric factors in males than females. PMID:23295598

  4. Variability of human upper airway collapsibility during sleep and the influence of body posture and sleep stage.

    PubMed

    Ong, Jeremy S L; Touyz, Gabby; Tanner, Sue; Hillman, David R; Eastwood, Peter R; Walsh, Jennifer H

    2011-12-01

    The critical pressure at which the pharynx collapses (Pcrit) is an objective measurement of upper airway collapsibility, an important pathogenetic factor in obstructive sleep apnoea. This study examined the inherent variability of passive Pcrit measurement during sleep and evaluated the effects of sleep stage and body posture on Pcrit. Repeated measurements of Pcrit were assessed in 23 individuals (15 male) with diagnosed obstructive sleep apnoea throughout a single overnight sleep study. Body posture and sleep stage were unrestricted. Applied upper airway pressure was repetitively reduced to obtain multiple measurements of Pcrit. In 20 subjects multiple measurements of Pcrit were obtained. The overall coefficient of repeatability for Pcrit measurement was 4.1 cm H₂O. Considering only the lateral posture, the coefficient was 4.8 cm H₂O. It was 3.3 cm H₂O in the supine posture. Pcrit decreased from the supine to lateral posture [supine mean 2.5 cm H₂O, 95% confidence interval (CI) 1.4-3.6; lateral mean 0.3 cm H₂O, 95% CI -0.8-1.4, P = 0.007] but did not vary with sleep stage (P = 0.91). This study has shown that the overall coefficient of repeatability was 4.1 cm H₂O, implying that the minimum detectable difference, with 95% probability, between two repeated Pcrit measurements in an individual is 4.1 cm H₂O. Such variability in overnight measures of Pcrit indicates that a single unqualified value of Pcrit cannot be used to characterize an individual's overall collapsibility during sleep. When within-subject variability is accounted for, change in body posture from supine to lateral significantly decreases passive pharyngeal collapsibility. PMID:21554464

  5. Variability of human upper airway collapsibility during sleep and the influence of body posture and sleep stage.

    PubMed

    Ong, Jeremy S L; Touyz, Gabby; Tanner, Sue; Hillman, David R; Eastwood, Peter R; Walsh, Jennifer H

    2011-12-01

    The critical pressure at which the pharynx collapses (Pcrit) is an objective measurement of upper airway collapsibility, an important pathogenetic factor in obstructive sleep apnoea. This study examined the inherent variability of passive Pcrit measurement during sleep and evaluated the effects of sleep stage and body posture on Pcrit. Repeated measurements of Pcrit were assessed in 23 individuals (15 male) with diagnosed obstructive sleep apnoea throughout a single overnight sleep study. Body posture and sleep stage were unrestricted. Applied upper airway pressure was repetitively reduced to obtain multiple measurements of Pcrit. In 20 subjects multiple measurements of Pcrit were obtained. The overall coefficient of repeatability for Pcrit measurement was 4.1 cm H₂O. Considering only the lateral posture, the coefficient was 4.8 cm H₂O. It was 3.3 cm H₂O in the supine posture. Pcrit decreased from the supine to lateral posture [supine mean 2.5 cm H₂O, 95% confidence interval (CI) 1.4-3.6; lateral mean 0.3 cm H₂O, 95% CI -0.8-1.4, P = 0.007] but did not vary with sleep stage (P = 0.91). This study has shown that the overall coefficient of repeatability was 4.1 cm H₂O, implying that the minimum detectable difference, with 95% probability, between two repeated Pcrit measurements in an individual is 4.1 cm H₂O. Such variability in overnight measures of Pcrit indicates that a single unqualified value of Pcrit cannot be used to characterize an individual's overall collapsibility during sleep. When within-subject variability is accounted for, change in body posture from supine to lateral significantly decreases passive pharyngeal collapsibility.

  6. Relationships between Malocclusion, Body Posture, and Nasopharyngeal Pathology in Pre-Orthodontic Children

    PubMed Central

    Šidlauskienė, Monika; Smailienė, Dalia; Lopatienė, Kristina; Čekanauskas, Emilis; Pribuišienė, Rūta; Šidlauskas, Mantas

    2015-01-01

    Background Malocclusion, body posture, and breathing pattern may be correlated, but this issue is still controversial. The aim of the study was to examine the relationship between the type of malocclusion, body posture, and nasopharyngeal obstruction in children aged 7–14 years. Material/Methods The study group comprised 94 patients aged 7–14 years (mean±SD: 11.9±2.1 years); 44 (46.8%) males and 50 (53.2%) females. All patients passed an examination performed by the same orthodontist (study model and cephalometric radiograph analysis), orthopedic surgeon (body posture examined from the front, side, and back), and otorhinolaryngologist (anterior and posterior rhinoscopy and pharyngoscopy) in a blind manner. Results Postural disorders were observed in 72 (76.6%) patients. Hypertrophy of the adenoids was diagnosed in 54 (57.4%) patients, hypertrophy of the tonsils in 85 (90.3%), nasal septum deviation in 51 (54.3%), and allergic rhinitis in 19 (20.2%) patients. There was a statistically significant correlation between presence of kyphotic posture and a reduction in the SNB angle, representing sagittal position of the mandible. Also, there was a statistically significant association between kyphotic posture and nasopharyngeal obstruction (54.1% of patients with nasopharyngeal obstruction were kyphotic, compared with 25% of patients with no nasopharyngeal obstruction; p=0.02). Kyphotic posture and reduced SNB angle were more common among males. Conclusions We concluded that: 1) there was a significant association between the sagittal position of the mandible (SNB angle) and a kyphotic posture; 2) kyphotic posture was significantly more common among patients with nasopharyngeal obstruction. PMID:26086193

  7. Kinematid Parameters of Corrective Postural Responses Differ between Upper and Lower Body Perturbations

    NASA Technical Reports Server (NTRS)

    Sayenko, G.

    2004-01-01

    Balance control is disrupted following prolonged microgravity exposure, and to better understand this, both upper and lower body perturbations have been used to study postural control in space flight crewmembers. However, differences between several postural response indicators observed using the two techniques suggest that different sensory systems may be involved in organizing responses to these different perturbation approaches. The present study sought to compare differences in parameters of corrective postural responses between upper body perturbations (pushes to the chest) and forward translations of the support surface. Nine subjects participated in this study. Forward translations were performed using a NeuroCom EquiTest(TM) CDP system, which was synchronized with a Northern Digital OptoTrak motion tracking system (3 subjects). Chest pushes were applied using a hand-held force transducer device and were performed using a stabilometric system (6 subjects). Analysis of EMG has shown that: i) the earliest response of the leg muscles was registered significantly later during forward translation of the support surface than during chest pushes, and ii) there was a tendency for the different order of leg muscles activation during the translation tests. Analysis of the kinematic data showed a significant difference in the subject's body segments inclinations during corrective postural responses to upper and lower body perturbations. It appears that upper body perturbations likely engage the vestibular system more rapidly, while lower body perturbations likely engage somatosensory systems more rapidly. These differences must be taken into account when choosing the type of perturbation for testing postural function.

  8. Longitudinal Study Evaluating Postural Balance of Young Athletes.

    PubMed

    Steinberg, Nili; Nemet, Dan; Pantanowitz, Michal; Zeev, Aviva; Hallumi, Monder; Sindiani, Mahmood; Meckel, Yoav; Eliakim, Alon

    2016-02-01

    Repeated anaerobic conditions during athletic performance may cause general and local fatigue that result in postural balance deficit. Evidence suggests that improved postural balance during athletic training may decrease the risk for fallings and traumatic injuries among athletes. Twenty athletes (12 girls, 8 boys) and 20 controls (12 girls, 8 boys) ages 10-15 years participated in the current study. All athletes were active in an 8-month physical activity program, 3 times per week for 90 min., specific to basketball, soccer, or athletic training. The control children participated in physical education at school only, with no involvement in organized extracurricular sports. All participants were evaluated for postural balance in three assessments over one year (at 4-mo intervals); the Interactive Balance System machine (Tetrax device) was used to assess balance at three test times (pre-, post-, and 10 min) after a session of a repeated sprint anaerobic test, consisting of 12 × 20 m run starting every 20 sec. The athletes had better postural balance than controls. There were different group patterns of change over the sessions; a significant interaction of session and group indicated that postural balance of the groups differed. The contribution of low sway frequencies (F1) and high sway frequencies (F6) differed between the controls and the athletes group. Results suggested that although athletes had better postural balance, improvement should be encouraged during training over the sessions and seasons, with special awareness of the balance deficit that occurs immediately after anaerobic stress and at the end of the season, to decrease the risk of injuries. PMID:27420320

  9. Longitudinal Study Evaluating Postural Balance of Young Athletes.

    PubMed

    Steinberg, Nili; Nemet, Dan; Pantanowitz, Michal; Zeev, Aviva; Hallumi, Monder; Sindiani, Mahmood; Meckel, Yoav; Eliakim, Alon

    2016-02-01

    Repeated anaerobic conditions during athletic performance may cause general and local fatigue that result in postural balance deficit. Evidence suggests that improved postural balance during athletic training may decrease the risk for fallings and traumatic injuries among athletes. Twenty athletes (12 girls, 8 boys) and 20 controls (12 girls, 8 boys) ages 10-15 years participated in the current study. All athletes were active in an 8-month physical activity program, 3 times per week for 90 min., specific to basketball, soccer, or athletic training. The control children participated in physical education at school only, with no involvement in organized extracurricular sports. All participants were evaluated for postural balance in three assessments over one year (at 4-mo intervals); the Interactive Balance System machine (Tetrax device) was used to assess balance at three test times (pre-, post-, and 10 min) after a session of a repeated sprint anaerobic test, consisting of 12 × 20 m run starting every 20 sec. The athletes had better postural balance than controls. There were different group patterns of change over the sessions; a significant interaction of session and group indicated that postural balance of the groups differed. The contribution of low sway frequencies (F1) and high sway frequencies (F6) differed between the controls and the athletes group. Results suggested that although athletes had better postural balance, improvement should be encouraged during training over the sessions and seasons, with special awareness of the balance deficit that occurs immediately after anaerobic stress and at the end of the season, to decrease the risk of injuries.

  10. Time Changes with the Embodiment of Another’s Body Posture

    PubMed Central

    Nather, Francisco C.; Bueno, José L. O.; Bigand, Emmanuel; Droit-Volet, Sylvie

    2011-01-01

    The aim of the present study was to investigate whether the perception of presentation durations of pictures of different body postures was distorted as function of the embodied movement that originally produced these postures. Participants were presented with two pictures, one with a low-arousal body posture judged to require no movement and the other with a high-arousal body posture judged to require considerable movement. In a temporal bisection task with two ranges of standard durations (0.4/1.6 s and 2/8 s), the participants had to judge whether the presentation duration of each of the pictures was more similar to the short or to the long standard duration. The results showed that the duration was judged longer for the posture requiring more movement than for the posture requiring less movement. However the magnitude of this overestimation was relatively greater for the range of short durations than for that of longer durations. Further analyses suggest that this lengthening effect was mediated by an arousal effect of limited duration on the speed of the internal clock system. PMID:21637759

  11. Do bimanual coordination, tool use, and body posture contribute equally to hand preferences in bonobos?

    PubMed

    Bardo, Ameline; Pouydebat, Emmanuelle; Meunier, Hélène

    2015-05-01

    Approximately 90% of the human population is right-handed. The emergence of this hand preference in humans is thought to be linked to the ability to execute complex tasks and habitual bipedalism. In order to test these hypotheses, the present study explored, for the first time, hand preference in relation to both body posture (seated and bipedal) and task complexity (bimanual coordination and two tool use tasks of different complexity) in bonobos (Pan paniscus). Few studies have explored the effects of both posture and task complexity on handedness, and investigations with bonobos are scarce, particularly studies on tool use. Our study aims to overcome such a gap by addressing two main questions: 1) Does a bipedal posture increase the strength of hand preference and/or create a directional bias to the use of the right hand? 2) Independent of body posture, does task complexity increase the strength of the hand preference and/or create a directional bias to the use of the right hand? Our results show that independent of body posture, the more complex the task, the more lateralization occurred. Moreover, subjects tended to be right-handed for tasks involving tool use. However, posture had no significant effect on hand preference in the tasks tested here. Therefore, for a given task, bonobos were not more lateralized in a bipedal posture than in a seated one. Task complexity might thus have contributed more than bipedal posture to the emergence of human lateralization and the preponderance of right-handedness, although a larger sample size and more data are needed to be conclusive. PMID:25870160

  12. Hierarchical error evaluation: the role of medial-frontal cortex in postural control.

    PubMed

    Hassall, Cameron D; MacLean, Stephane; Krigolson, Olave E

    2014-01-01

    Motor error evaluation appears to be a hierarchically organized process subserved by 2 distinct systems: a higher level system within medial-frontal cortex responsible for movement outcome evaluation (high-level error evaluation) and a lower level posterior system(s) responsible for the mediation of within-movement errors (low-level error evaluation). While a growing body of evidence suggests that a reinforcement learning system within medial-frontal cortex plays a crucial role in the evaluation of high-level errors made during discrete reaching movements and continuous motor tracking, the role of this system in postural control is currently unclear. Participants learned a postural control task via a feedback-driven trial-and-error shaping process. In line with previous findings, electroencephalographic recordings revealed that feedback about movement outcomes elicited a feedback error-related negativity: a component of the human event-related brain potential associated with high-level outcome evaluation within medial-frontal cortex. Thus, the data provide evidence that a high-level error-evaluation system within medial-frontal cortex plays a key role in learning to control our body posture.

  13. Body appendages fine-tune posture and moments in freely manoeuvring fruit flies.

    PubMed

    Berthé, Ruben; Lehmann, Fritz-Olaf

    2015-10-01

    The precise control of body posture by turning moments is key to elevated locomotor performance in flying animals. Although elevated moments for body stabilization are typically produced by wing aerodynamics, animals also steer using drag on body appendages, shifting their centre of body mass, and changing moments of inertia caused by active alterations in body shape. To estimate the instantaneous contribution of each of these components for posture control in an insect, we three-dimensionally reconstructed body posture and movements of body appendages in freely manoeuvring fruit flies (Drosophila melanogaster) by high-speed video and experimentally scored drag coefficients of legs and body trunk at low Reynolds number. The results show that the sum of leg- and abdomen-induced yaw moments dominates wing-induced moments during 17% of total flight time but is, on average, 7.2-times (roll, 3.4-times) smaller during manoeuvring. Our data reject a previous hypothesis on synergistic moment support, indicating that drag on body appendages and mass-shift inhibit rather than support turning moments produced by the wings. Numerical modelling further shows that hind leg extension alters the moments of inertia around the three main body axes of the animal by not more than 6% during manoeuvring, which is significantly less than previously reported for other insects. In sum, yaw, pitch and roll steering by body appendages probably fine-tune turning behaviour and body posture, without providing a significant advantage for posture stability and moment support. Motion control of appendages might thus be part of the insect's trimming reflexes, which reduce imbalances in moment generation caused by unilateral wing damage and abnormal asymmetries of the flight apparatus.

  14. Body appendages fine-tune posture and moments in freely manoeuvring fruit flies.

    PubMed

    Berthé, Ruben; Lehmann, Fritz-Olaf

    2015-10-01

    The precise control of body posture by turning moments is key to elevated locomotor performance in flying animals. Although elevated moments for body stabilization are typically produced by wing aerodynamics, animals also steer using drag on body appendages, shifting their centre of body mass, and changing moments of inertia caused by active alterations in body shape. To estimate the instantaneous contribution of each of these components for posture control in an insect, we three-dimensionally reconstructed body posture and movements of body appendages in freely manoeuvring fruit flies (Drosophila melanogaster) by high-speed video and experimentally scored drag coefficients of legs and body trunk at low Reynolds number. The results show that the sum of leg- and abdomen-induced yaw moments dominates wing-induced moments during 17% of total flight time but is, on average, 7.2-times (roll, 3.4-times) smaller during manoeuvring. Our data reject a previous hypothesis on synergistic moment support, indicating that drag on body appendages and mass-shift inhibit rather than support turning moments produced by the wings. Numerical modelling further shows that hind leg extension alters the moments of inertia around the three main body axes of the animal by not more than 6% during manoeuvring, which is significantly less than previously reported for other insects. In sum, yaw, pitch and roll steering by body appendages probably fine-tune turning behaviour and body posture, without providing a significant advantage for posture stability and moment support. Motion control of appendages might thus be part of the insect's trimming reflexes, which reduce imbalances in moment generation caused by unilateral wing damage and abnormal asymmetries of the flight apparatus. PMID:26347566

  15. Sad or Fearful? The Influence of Body Posture on Adults' and Children's Perception of Facial Displays of Emotion

    ERIC Educational Resources Information Center

    Mondloch, Catherine J.

    2012-01-01

    The current research investigated the influence of body posture on adults' and children's perception of facial displays of emotion. In each of two experiments, participants categorized facial expressions that were presented on a body posture that was congruent (e.g., a sad face on a body posing sadness) or incongruent (e.g., a sad face on a body…

  16. Effect of posture on body temperature of young men in cold air.

    PubMed

    Donaldson, G C; Scarborough, M; Mridha, K; Whelan, L; Caunce, M; Keatinge, W R

    1996-01-01

    We studied eight young adult men to see whether a supine posture caused a fall in body core temperature in the cold, as it does in thermoneutral conditions. In air at 31 degrees C (thermoneutral), a supine posture for 3 h reduced mean aural, gastric, oesophageal and rectal temperatures by 0.2-0.4 degree C, compared to upright and increased femoral artery blood flow from 278 (SEM 42)ml.min-1 whilst upright to 437 (SEM 42) ml.min-1 whilst supine. In cold air (8 degrees C) the supine posture failed to reduce these temperatures [corrected] significantly, or to increase femoral blood flow: it reduced heart rate, and increased arterial systolic and pulse pressures adjusted to carotid sinus level, less than in thermoneutral conditions. However, the behaviour of core temperature at the four sites was significantly nonuniform between the two postures in the cold, mainly because the supine posture tended to reduce rectal temperature. It may have done so by reducing heat production in the muscles of the pelvis, since it reduced overall metabolic rate from 105 (SEM 8) to 87 (SEM 4) W.m-2 in the cold. In other respects the results indicated that posture ceased to have an important effect on body core temperatures during cold stress.

  17. Pain communication through body posture: the development and validation of a stimulus set.

    PubMed

    Walsh, Joseph; Eccleston, Christopher; Keogh, Edmund

    2014-11-01

    Pain can be communicated nonverbally through facial expressions, vocalisations, and bodily movements. Most studies have focussed on the facial display of pain, whereas there is little research on postural display. Stimulus sets for facial and vocal expressions of pain have been developed, but there is no equivalent for body-based expressions. Reported here is the development of a new stimulus set of dynamic body postures that communicate pain and basic emotions. This stimulus set is designed to facilitate research into the bodily communication of pain. We report a 3-phase development and validation study. First 16 actors performed affective body postures for pain, as well as happiness, sadness, fear, disgust, surprise, anger, and neutral expressions. Second, 20 observers independently selected the best image stimuli based on the accuracy of emotion identification and valence/arousal ratings. Third, to establish reliability, this accuracy and valence rating procedure was repeated with a second independent group of 40 participants. A final set of 144 images with good reliability was established and is made available. Results demonstrate that pain, along with basic emotions, can be communicated through body posture. Cluster analysis demonstrates that pain and emotion are recognised with a high degree of specificity. In addition, pain was rated as the most unpleasant (negative valence) of the expressions, and was associated with a high level of arousal. For the first time, specific postures communicating pain are described. The stimulus set is provided as a tool to facilitate the study of nonverbal pain communication, and its possible uses are discussed.

  18. Postural discomfort and perceived exertion in standardized box-holding postures.

    PubMed

    Olendorf, M R; Drury, C G

    2001-12-15

    To help in the design or redesign of workplaces it would be helpful to know in advance the postural stress consequences of a wide range of body postures. This experiment evaluated 168 postures chosen to represent those in the Ovako Working-posture Analysing System (OWAS) using Rated Perceived Exertion (RPE) and Body Part Discomfort (BPD) measures. The postures comprised all combinations of three arm postures, four back postures, seven leg postures and two forces (weights of held boxes). Twelve male subjects held each posture for a fixed duration (20 s) before providing RPE and BPD ratings. Analysis of the ratings gave highly significant main effects, with the major driver being the object weight. As each factor was varied, the largest effect was on the body region corresponding to that factor. A simple main-effects-only additive model explained 91% of the variance of RPE means for the postures.

  19. Postural discomfort and perceived exertion in standardized box-holding postures.

    PubMed

    Olendorf, M R; Drury, C G

    2001-12-15

    To help in the design or redesign of workplaces it would be helpful to know in advance the postural stress consequences of a wide range of body postures. This experiment evaluated 168 postures chosen to represent those in the Ovako Working-posture Analysing System (OWAS) using Rated Perceived Exertion (RPE) and Body Part Discomfort (BPD) measures. The postures comprised all combinations of three arm postures, four back postures, seven leg postures and two forces (weights of held boxes). Twelve male subjects held each posture for a fixed duration (20 s) before providing RPE and BPD ratings. Analysis of the ratings gave highly significant main effects, with the major driver being the object weight. As each factor was varied, the largest effect was on the body region corresponding to that factor. A simple main-effects-only additive model explained 91% of the variance of RPE means for the postures. PMID:11936827

  20. Evaluation of Postural Control in Glaucoma Patients Using a Virtual 1 Reality Environment

    PubMed Central

    Diniz-Filho, Alberto; Boer, Erwin R.; Gracitelli, Carolina P. B.; Abe, Ricardo Y.; van Driel, Nienke; Yang, Zhiyong; Medeiros, Felipe A.

    2015-01-01

    Purpose To evaluate postural control using a dynamic virtual reality environment and the relationship between postural metrics and history of falls in glaucoma patients. Design Cross-sectional study. Participants The study involved 42 glaucoma patients with repeatable visual field defects on standard automated perimetry (SAP) and 38 control healthy subjects. Methods Patients underwent evaluation of postural stability by a force platform during presentation of static and dynamic visual stimuli on stereoscopic head-mounted goggles. The dynamic visual stimuli presented rotational and translational ecologically valid peripheral background perturbations. Postural stability was also tested in a completely dark field to assess somatosensory and vestibular contributions to postural control. History of falls was evaluated by a standard questionnaire. Main Outcome Measures Torque moments around the center of foot pressure on the force platform were measured and the standard deviations (STD) of these torque moments were calculated as a measurement of postural stability and reported in Newton meter (Nm). The association with history of falls was investigated using Poisson regression models. Age, gender, body mass index, severity of visual field defect, best-corrected visual acuity, and STD on dark field condition were included as confounding factors. Results Glaucoma patients had larger overall STD than controls during both translational (5.12 ± 2.39 Nm vs. 3.85 ± 1.82 Nm, respectively; P = 0.005) as well as rotational stimuli (5.60 ± 3.82 Nm vs. 3.93 ± 2.07 Nm, respectively; P = 0.022). Postural metrics obtained during dynamic visual stimuli performed better in explaining history of falls compared to those obtained in static and dark field condition. In the multivariable model, STD values in the mediolateral direction during translational stimulus were significantly associated with history of falls in glaucoma patients (incidence-rate ratio = 1.85; 95% CI: 1.30 – 2

  1. Evaluation of the temporal structure of postural sway fluctuations based on a comprehensive set of analysis tools

    NASA Astrophysics Data System (ADS)

    Kirchner, M.; Schubert, P.; Schmidtbleicher, D.; Haas, C. T.

    2012-10-01

    The analysis of postural control has a long history. Traditionally, the amount of body sway is solely used as an index of postural stability. Although this leads to some extent to an effective evaluation of balance performance, the control mechanisms involved have not yet been fully understood. The concept of nonlinear dynamics suggests that variability in the motor output is not randomness but structure, providing the stimulus to reveal the functionality of postural sway. The present work evaluates sway dynamics by means of COP excursions in a quiet standing task versus a dual-task condition in three different test times (30, 60, 300 s). Besides the application of traditional methods-which estimate the overall size of sway-the temporal pattern of body sway was quantified via wavelet transform, multiscale entropy and fractal analysis. We found higher sensitivity of the structural parameters to modulations of postural control strategies and partly an improved evaluation of sway dynamics in longer recordings. It could be shown that postural control modifications take place on different timescales corresponding to the interplay of the sensory systems. A continued application of nonlinear analysis can help to better understand postural control mechanisms.

  2. Cells in monkey STS responsive to articulated body motions and consequent static posture: a case of implied motion?

    PubMed

    Jellema, Tjeerd; Perrett, David I

    2003-01-01

    We show that populations of visually responsive cells in the anterior part of the superior temporal sulcus (STSa) of the macaque monkey code for the sight of both specific articulated body actions and the consequent articulated static body postures. We define articulated actions as actions where one body part (e.g. a limb or head) moves with respect to the remainder of the body which remains static; conversely non-articulated actions are actions where the equivalent body parts do not move with respect to each other but move as one. Similarly, articulated static body postures contain a torsion or rotation between parts, while non-articulated postures do not. Cells were tested with the sight of articulated and non-articulated actions followed by the resultant articulated or non-articulated static body postures. In addition, the static body postures that formed the start and end of the actions were tested in isolation. The cells studied did not respond to the sight of non-articulated static posture, which formed the starting-point of the action, but responded vigorously to the articulated static posture that formed the end-point of the action. Other static postures resembling the articulated end-point posture, but which were in a more relaxed muscular state (i.e. non-articulated), did not evoke responses. The cells did not respond to body actions that were less often associated with the effective static articulated postures. Our results suggest that the cells' responses were related to the implied action rather than the static posture per se. We propose that the neural representations in STSa for actual biological motion may also extend to biological motion implied from static postures. These representations could play a role in producing the activity in the medial temporal/medial superior temporal (V5(MT)/MST) areas reported in fMRI studies when subjects view still photographs of people in action. PMID:14527537

  3. Human body 3D posture estimation using significant points and two cameras.

    PubMed

    Juang, Chia-Feng; Chen, Teng-Chang; Du, Wei-Chin

    2014-01-01

    This paper proposes a three-dimensional (3D) human posture estimation system that locates 3D significant body points based on 2D body contours extracted from two cameras without using any depth sensors. The 3D significant body points that are located by this system include the head, the center of the body, the tips of the feet, the tips of the hands, the elbows, and the knees. First, a linear support vector machine- (SVM-) based segmentation method is proposed to distinguish the human body from the background in red, green, and blue (RGB) color space. The SVM-based segmentation method uses not only normalized color differences but also included angle between pixels in the current frame and the background in order to reduce shadow influence. After segmentation, 2D significant points in each of the two extracted images are located. A significant point volume matching (SPVM) method is then proposed to reconstruct the 3D significant body point locations by using 2D posture estimation results. Experimental results show that the proposed SVM-based segmentation method shows better performance than other gray level- and RGB-based segmentation approaches. This paper also shows the effectiveness of the 3D posture estimation results in different postures.

  4. Pelvic Morphology, Body Posture and Standing Balance Characteristics of Adolescent Able-Bodied and Idiopathic Scoliosis Girls

    PubMed Central

    Stylianides, Georgios A.; Dalleau, Georges; Begon, Mickaël; Rivard, Charles-Hilaire; Allard, Paul

    2013-01-01

    The purpose of this study was to determine how pelvic morphology, body posture, and standing balance variables of scoliotic girls differ from those of able-bodied girls, and to classify neuro-biomechanical variables in terms of a lower number of unobserved variables. Twenty-eight scoliotic and twenty-five non-scoliotic able-bodied girls participated in this study. 3D coordinates of ten anatomic body landmarks were used to describe pelvic morphology and trunk posture using a Flock of Birds system. Standing balance was measured using a force plate to identify the center of pressure (COP), and its anteroposterior (AP) and mediolateral (ML) displacements. A multivariate analysis of variance (MANOVA) was performed to determine differences between the two groups. A factor analysis was used to identify factors that best describe both groups. Statistical differences were identified between the groups for each of the parameter types. While spatial orientation of the pelvis was similar in both groups, five of the eight trunk postural variables of the scoliotic group were significantly different that the able-bodied group. Also, five out of the seven standing balance variables were higher in the scoliotic girls. Approximately 60% of the variation is supported by 4 factors that can be associated with a set of variables; standing balance variables (factor 1), body posture variables (factor 2), and pelvic morphology variables (factors 3 and 4). Pelvic distortion, body posture asymmetry, and standing imbalance are more pronounced in scoliotic girls, when compared to able-bodied girls. These findings may be beneficial when addressing balance and ankle proprioception exercises for the scoliotic population. PMID:23875021

  5. [Biodynamic responses of the seated posture of human upper-body under horizontal and vertical stimuli].

    PubMed

    Wang, Xishi; Jiang, Fuchuan; Ma, Jian; Hou, Xinping

    2008-02-01

    In this paper, a biodynamic model of human upper-body in the seated posture is developed. Based on d'Alembert's principle, the non-linear biodynamic equation of the modelling is derivated. Furthermore, the function of frequency and amplitude of modelling is obtained by employing the KB method in the non-linear theory. The response of realistic human parameters and the external stimulus on the modelling is simulated by MATLAB. The results show that the modelling presents a plenty of non-linear characteristics. The parameters identified and the stable areas to keep the stabilization of upper-body in the seated posture are discussed. These data can be used to explain and estimate the mechanism for the maintenance of stable trunk posture due to the mechanical shocks transmitted through the vehicle seat.

  6. Evaluation of validity and reliability of a methodology for measuring human postural attitude and its relation to temporomandibular joint disorders

    PubMed Central

    Fernández, Ramón Fuentes; Carter, Pablo; Muñoz, Sergio; Silva, Héctor; Venegas, Gonzalo Hernán Oporto; Cantin, Mario; Ottone, Nicolás Ernesto

    2016-01-01

    INTRODUCTION Temporomandibular joint disorders (TMJDs) are caused by several factors such as anatomical, neuromuscular and psychological alterations. A relationship has been established between TMJDs and postural alterations, a type of anatomical alteration. An anterior position of the head requires hyperactivity of the posterior neck region and shoulder muscles to prevent the head from falling forward. This compensatory muscular function may cause fatigue, discomfort and trigger point activation. To our knowledge, a method for assessing human postural attitude in more than one plane has not been reported. Thus, the aim of this study was to design a methodology to measure the external human postural attitude in frontal and sagittal planes, with proper validity and reliability analyses. METHODS The variable postures of 78 subjects (36 men, 42 women; age 18–24 years) were evaluated. The postural attitudes of the subjects were measured in the frontal and sagittal planes, using an acromiopelvimeter, grid panel and Fox plane. RESULTS The method we designed for measuring postural attitudes had adequate reliability and validity, both qualitatively and quantitatively, based on Cohen’s Kappa coefficient (> 0.87) and Pearson’s correlation coefficient (r = 0.824, > 80%). CONCLUSION This method exhibits adequate metrical properties and can therefore be used in further research on the association of human body posture with skeletal types and TMJDs. PMID:26768173

  7. Human body area factors for radiation exchange analysis: standing and walking postures.

    PubMed

    Park, Sookuk; Tuller, Stanton E

    2011-09-01

    Effective radiation area factors (f (eff)) and projected area factors (f (p)) of unclothed Caucasians' standing and walking postures used in estimating human radiation exchange with the surrounding environment were determined from a sample of adults in Canada. Several three-dimensional (3D) computer body models were created for standing and walking postures. Only small differences in f (eff) and f (p) values for standing posture were found between gender (male or female) and body type (normal- or over-weight). Differences between this study and previous studies were much larger: ≤0.173 in f (p) and ≤0.101 in f (eff). Directionless f (p) values for walking posture also had only minor differences between genders and positions in a stride. However, the differences of mean directional f (p) values of the positions dependent on azimuth angles were large enough, ≤0.072, to create important differences in modeled radiation receipt. Differences in f (eff) values were small: 0.02 between the normal-weight male and female models and up to 0.033 between positions in a stride. Variations of directional f (p) values depending on solar altitudes for walking posture were narrower than those for standing posture. When both standing and walking postures are considered, the mean f (eff) value, 0.836, of standing (0.826) and walking (0.846) could be used. However, f (p) values should be selected carefully because differences between directional and directionless f (p) values were large enough that they could influence the estimated level of human thermal sensation.

  8. 4D human body posture estimation based on a motion capture system and a multi-rigid link model.

    PubMed

    Yoshikawa, Naoya; Suzuki, Yasuyuki; Ozaki, Wataru; Yamamoto, Tomohisa; Nomura, Taishin

    2012-01-01

    Human motion analysis in various fields such as neurophysiology, clinical medicine, and sports sciences utilizes a multi-rigid link model of a human body for considering kinetics by solving inverse dynamics of a motion, in which a motion capture system with reflective markers are often used to measure the motion, and then the obtained motion are mapped onto the multi-rigid link model. However, algorithms for such a mapping from spatio-temporal positions of the markers to the corresponding posture of the model are not always fully disclosed. Moreover, a common difficulty for such algorithms is an error caused by displacements of the markers attached on the body surface, referred to as the skin motion error. In this study, we developed a simple algorithm that maps positions of the markers to the corresponding posture of a rigid link model, and examined accuracy of the algorithm by evaluating quantitatively differences between the measured and the estimated posture. We also analyzed the skin motion error. It is shown that magnitude of the error was determined not only by the amplitude of the skin motion, but also by the direction of the marker displacement relative to the frame of reference attached to each segment of the body.

  9. Towards a Mechanistic Understanding of the Effects of Body Posture on Facial Emotion Categorization.

    PubMed

    Civile, Ciro; Obhi, Sukhvinder S

    2015-01-01

    This study investigated the causes of the face-body congruence effect (FBCE), which refers to the advantage in performance when participants are asked to categorize emotional faces compounded with emotional matching body postures (congruent) compared with incongruent face-body compound stimuli (body postures mismatching the facial emotions). Experiment 1 showed that manipulations aiming to alter holistic processing significantly reduced the FBCE. In particular, the disruption of holistic processing affected significantly the performance for congruent composites. However, no effect was obtained on the incongruent stimuli. In Experiment 2, the inversion manipulation showed a clear disadvantage for incongruent stimuli brought by the disruption of the single feature orientation information. Thus, we found confirmation of the different processing involved in perceiving congruent and incongruent stimuli. Finally, Experiment 3 confirmed that we are able to reduce entirely the FBCE when the orientation of the units (the face and the body) constituting the incongruent composites is matched. PMID:26442343

  10. Towards a Mechanistic Understanding of the Effects of Body Posture on Facial Emotion Categorization.

    PubMed

    Civile, Ciro; Obhi, Sukhvinder S

    2015-01-01

    This study investigated the causes of the face-body congruence effect (FBCE), which refers to the advantage in performance when participants are asked to categorize emotional faces compounded with emotional matching body postures (congruent) compared with incongruent face-body compound stimuli (body postures mismatching the facial emotions). Experiment 1 showed that manipulations aiming to alter holistic processing significantly reduced the FBCE. In particular, the disruption of holistic processing affected significantly the performance for congruent composites. However, no effect was obtained on the incongruent stimuli. In Experiment 2, the inversion manipulation showed a clear disadvantage for incongruent stimuli brought by the disruption of the single feature orientation information. Thus, we found confirmation of the different processing involved in perceiving congruent and incongruent stimuli. Finally, Experiment 3 confirmed that we are able to reduce entirely the FBCE when the orientation of the units (the face and the body) constituting the incongruent composites is matched.

  11. Automatic techniques for 3D reconstruction of critical workplace body postures from range imaging data

    NASA Astrophysics Data System (ADS)

    Westfeld, Patrick; Maas, Hans-Gerd; Bringmann, Oliver; Gröllich, Daniel; Schmauder, Martin

    2013-11-01

    The paper shows techniques for the determination of structured motion parameters from range camera image sequences. The core contribution of the work presented here is the development of an integrated least squares 3D tracking approach based on amplitude and range image sequences to calculate dense 3D motion vector fields. Geometric primitives of a human body model are fitted to time series of range camera point clouds using these vector fields as additional information. Body poses and motion information for individual body parts are derived from the model fit. On the basis of these pose and motion parameters, critical body postures are detected. The primary aim of the study is to automate ergonomic studies for risk assessments regulated by law, identifying harmful movements and awkward body postures in a workplace.

  12. Holistic processing of human body postures: evidence from the composite effect.

    PubMed

    Willems, Sam; Vrancken, Leia; Germeys, Filip; Verfaillie, Karl

    2014-01-01

    The perception of socially relevant stimuli (e.g., faces and bodies) has received considerable attention in the vision science community. It is now widely accepted that human faces are processed holistically and not only analytically. One observation that has been taken as evidence for holistic face processing is the face composite effect: two identical top halves of a face tend to be perceived as being different when combined with different bottom halves. This supports the hypothesis that face processing proceeds holistically. Indeed, the interference effect disappears when the two face parts are misaligned (blocking holistic perception). In the present study, we investigated whether there is also a composite effect for the perception of body postures: are two identical body halves perceived as being in different poses when the irrelevant body halves differ from each other? Both a horizontal (i.e., top-bottom body halves; Experiment 1) and a vertical composite effect (i.e., left-right body halves; Experiment 2) were examined by means of a delayed matching-to-sample task. Results of both experiments indicate the existence of a body posture composite effect. This provides evidence for the hypothesis that body postures, as faces, are processed holistically.

  13. Imitation of Body Postures and Hand Movements in Children with Specific Language Impairment

    ERIC Educational Resources Information Center

    Marton, Klara

    2009-01-01

    Within the domain-general theory of language impairment, this study examined body posture and hand movement imitation in children with specific language impairment (SLI) and in their age-matched peers. Participants included 40 children with SLI (5 years 3 months to 6 years 10 months of age) and 40 children with typical language development (5…

  14. Brief Report: Perception of Body Posture--What Individuals with Autism Spectrum Disorder Might Be Missing

    ERIC Educational Resources Information Center

    Reed, Catherine L.; Beall, Paula M.; Stone, Valerie E.; Kopelioff, Lila; Pulham, Danielle J.; Hepburn, Susan L.

    2007-01-01

    Autism has been associated with atypical face and configural processing, as indicated by the lack of a face inversion effect (better recognition of upright than inverted faces). We investigated whether such atypical processing was restricted to the face or extended to social information found in body postures. An inversion paradigm compared…

  15. Effects of experimental occlusal interference on body posture: an optoelectronic stereophotogrammetric analysis.

    PubMed

    Marini, I; Gatto, M R; Bartolucci, M L; Bortolotti, F; Alessandri Bonetti, G; Michelotti, A

    2013-07-01

    In recent years, there has been increasing interest in the relationship between dental occlusion and body posture both among people and in scientific literature. The aim of the present longitudinal study is to investigate the effects of an experimental occlusal interference on body posture by means of a force platform and an optoelectronic stereophotogrammetric analysis. An occlusal interference of a 0- to 2-mm-thick glass composite was prepared to disturb the intercuspal position while not creating interference during lateral or protrusive mandibular excursions. Frontal and sagittal kinematic parameters, dynamic gait measurements and superficial electromyographic (SEMG) activity of head and neck muscles were performed on 12 healthy subjects. Measurements were taken 10 days before the application of the occlusal interference, and then immediately before the application, the day after it, and at a distance of 7 and 14 days under four different exteroceptive conditions. The outcomes of this study show that an occlusal interference does not modify significantly over time static and dynamic parameters of body posture under different exteroceptive conditions. It has a minimal influence only on the frontal kinematic parameters related to mandibular position, and it induces a transient increase of the activity of masticatory muscles. In this study, the experimental occlusal interference did not significantly influence the body posture during a 14-day follow-up period.

  16. A wireless accelerometer-based body posture stability detection system and its application for meditation practitioners.

    PubMed

    Chang, Kang-Ming; Chen, Sih-Huei; Lee, Hsin-Yi; Ching, Congo Tak-Shing; Huang, Chun-Lung

    2012-12-18

    The practice of meditation has become an interesting research issue in recent decades. Meditation is known to be beneficial for health improvement and illness reduction and many studies on meditation have been made, from both the physiological and psychological points of view. It is a fundamental requirement of meditation practice to be able to sit without body motion. In this study, a novel body motion monitoring and estimation system has been developed. A wireless tri-axis accelerometer is used to measure body motion. Both a mean and maximum motion index is derived from the square summation of three axes. Two experiments were conducted in this study. The first experiment was to investigate the motion index baseline among three leg-crossing postures. The second experiment was to observe posture dynamics for thirty minute's meditation. Twenty-six subjects participated in the experiments. In one experiment, thirteen subjects were recruited from an experienced meditation group (meditation experience > 3 years); and the other thirteen subjects were beginners (meditation experience < 1 years). There was a significant posture stability difference between both groups in terms of either mean or maximum parameters (p < 0.05), according to the results of the experiment. Results from another experiment showed that the motion index is different for various postures, such as full-lotus < half-lotus < non-lotus.

  17. Effective seat-to-head transmissibility in whole-body vibration: Effects of posture and arm position

    NASA Astrophysics Data System (ADS)

    Rahmatalla, Salam; DeShaw, Jonathan

    2011-12-01

    Seat-to-head transmissibility is a biomechanical measure that has been widely used for many decades to evaluate seat dynamics and human response to vibration. Traditionally, transmissibility has been used to correlate single-input or multiple-input with single-output motion; it has not been effectively used for multiple-input and multiple-output scenarios due to the complexity of dealing with the coupled motions caused by the cross-axis effect. This work presents a novel approach to use transmissibility effectively for single- and multiple-input and multiple-output whole-body vibrations. In this regard, the full transmissibility matrix is transformed into a single graph, such as those for single-input and single-output motions. Singular value decomposition and maximum distortion energy theory were used to achieve the latter goal. Seat-to-head transmissibility matrices for single-input/multiple-output in the fore-aft direction, single-input/multiple-output in the vertical direction, and multiple-input/multiple-output directions are investigated in this work. A total of ten subjects participated in this study. Discrete frequencies of 0.5-16 Hz were used for the fore-aft direction using supported and unsupported back postures. Random ride files from a dozer machine were used for the vertical and multiple-axis scenarios considering two arm postures: using the armrests or grasping the steering wheel. For single-input/multiple-output, the results showed that the proposed method was very effective in showing the frequencies where the transmissibility is mostly sensitive for the two sitting postures and two arm positions. For multiple-input/multiple-output, the results showed that the proposed effective transmissibility indicated higher values for the armrest-supported posture than for the steering-wheel-supported posture.

  18. Visually guided adjustments of body posture in the roll plane.

    PubMed

    Tarnutzer, A A; Bockisch, C J; Straumann, D

    2013-05-01

    Body position relative to gravity is continuously updated to prevent falls. Therefore, the brain integrates input from the otoliths, truncal graviceptors, proprioception and vision. Without visual cues estimated direction of gravity mainly depends on otolith input and becomes more variable with increasing roll-tilt. Contrary, the discrimination threshold for object orientation shows little modulation with varying roll orientation of the visual stimulus. Providing earth-stationary visual cues, this retinal input may be sufficient to perform self-adjustment tasks successfully, with resulting variability being independent of whole-body roll orientation. We compared conditions with informative (earth-fixed) and non-informative (body-fixed) visual cues. If the brain uses exclusively retinal input (if earth-stationary) to solve the task, trial-to-trial variability will be independent from the subject's roll orientation. Alternatively, central integration of both retinal (earth-fixed) and extra-retinal inputs will lead to increasing variability when roll-tilted. Subjects, seated on a motorized chair, were instructed to (1) align themselves parallel to an earth-fixed line oriented earth-vertical or roll-tilted 75° clockwise; (2) move a body-fixed line (aligned with the body-longitudinal axis or roll-tilted 75° counter-clockwise to it) by adjusting their body position until the line was perceived earth-vertical. At 75° right-ear-down position, variability increased significantly (p < 0.05) compared to upright in both paradigms, suggesting that, despite the earth-stationary retinal cues, extra-retinal input is integrated. Self-adjustments in the roll-tilted position were significantly (p < 0.01) more precise for earth-fixed cues than for body-fixed cues, underlining the importance of earth-stable visual cues when estimates of gravity become more variable with increasing whole-body roll. PMID:23535837

  19. Visually guided adjustments of body posture in the roll plane.

    PubMed

    Tarnutzer, A A; Bockisch, C J; Straumann, D

    2013-05-01

    Body position relative to gravity is continuously updated to prevent falls. Therefore, the brain integrates input from the otoliths, truncal graviceptors, proprioception and vision. Without visual cues estimated direction of gravity mainly depends on otolith input and becomes more variable with increasing roll-tilt. Contrary, the discrimination threshold for object orientation shows little modulation with varying roll orientation of the visual stimulus. Providing earth-stationary visual cues, this retinal input may be sufficient to perform self-adjustment tasks successfully, with resulting variability being independent of whole-body roll orientation. We compared conditions with informative (earth-fixed) and non-informative (body-fixed) visual cues. If the brain uses exclusively retinal input (if earth-stationary) to solve the task, trial-to-trial variability will be independent from the subject's roll orientation. Alternatively, central integration of both retinal (earth-fixed) and extra-retinal inputs will lead to increasing variability when roll-tilted. Subjects, seated on a motorized chair, were instructed to (1) align themselves parallel to an earth-fixed line oriented earth-vertical or roll-tilted 75° clockwise; (2) move a body-fixed line (aligned with the body-longitudinal axis or roll-tilted 75° counter-clockwise to it) by adjusting their body position until the line was perceived earth-vertical. At 75° right-ear-down position, variability increased significantly (p < 0.05) compared to upright in both paradigms, suggesting that, despite the earth-stationary retinal cues, extra-retinal input is integrated. Self-adjustments in the roll-tilted position were significantly (p < 0.01) more precise for earth-fixed cues than for body-fixed cues, underlining the importance of earth-stable visual cues when estimates of gravity become more variable with increasing whole-body roll.

  20. Swimming fundamentals: turning performance of leopard sharks (Triakis semifasciata) is predicted by body shape and postural reconfiguration.

    PubMed

    Porter, Marianne E; Roque, Cassandra M; Long, John H

    2011-12-01

    Turns are essential maneuvers that sharks employ when foraging, feeding, and migrating. How well any individual performs in turning is determined, in part, by the static form and postural reconfiguration of its body. Since the importance of postural reconfiguration in determining turning performance is not well understood, our goal was to examine how body form and posture correlate with turning performance in juvenile leopard sharks, Triakis semifasciata. From videos of sharks turning laterally in yaw, performance was measured as turning radius, turning angle, angular speed of the head, and translational speed of the body along its path. Body form variables included the body's length, mass, width, second moment of area, and mass moment of inertia. Postural variables included body-bending coefficient, body flexion at different longitudinal positions, and lag time between body flexion and turning of the center of rotation. Using step-wise linear regression followed by multiple regression, each performance variable was regressed onto three pools of independent variables: (i) all form variables alone, (ii) all postural variables alone, and (iii) a combination of all form and postural variables. From these correlations, it appears that turning performance may be controlled primarily by the magnitude and timing of the flexion of the body. In other words, sharks alter how they turn by changing the pattern in which they bend their bodies; the body acts as a dynamically reconfiguring rudder.

  1. A passerine spreads its tail to facilitate a rapid recovery of its body posture during hovering

    PubMed Central

    Su, Jian-Yuan; Ting, Shang-Chieh; Chang, Yu-Hung; Yang, Jing-Tang

    2012-01-01

    We demonstrate experimentally that a passerine exploits tail spreading to intercept the downward flow induced by its wings to facilitate the recovery of its posture. The periodic spreading of its tail by the White-eye bird exhibits a phase correlation with both wingstroke motion and body oscillation during hovering flight. During a downstroke, a White-eye's body undergoes a remarkable pitch-down motion, with the tail undergoing an upward swing. This pitch-down motion becomes appropriately suppressed at the end of the downstroke; the bird's body posture then recovers gradually to its original status. Employing digital particle-image velocimetry, we show that the strong downward flow induced by downstroking the wings serves as an external jet flow impinging upon the tail, providing a depressing force on the tail to counteract the pitch-down motion of the bird's body. Spreading of the tail enhances a rapid recovery of the body posture because increased forces are experienced. The maximum force experienced by a spread tail is approximately 2.6 times that of a non-spread tail. PMID:22258552

  2. Whole body vibration and posture as risk factors for low back pain among forklift truck drivers

    NASA Astrophysics Data System (ADS)

    Hoy, J.; Mubarak, N.; Nelson, S.; Sweerts de Landas, M.; Magnusson, M.; Okunribido, O.; Pope, M.

    2005-06-01

    A cross-sectional study was conducted to investigate the risks from whole-body vibration and posture demands for low back pain (LBP) among forklift truck (forklift) drivers. Using a validated questionnaire, information about health history was obtained over a period of two weeks in face-to-face interviews. The forklift drivers were observed in respect of their sitting posture, including frequency with which different positions were adopted (bending, leaning and twisting) and postural analyses were conducted using the OWAS and RULA techniques. Forklift vibrations at the seat (exposure) were measured in the three orthogonal axes ( x-fore and aft, y-lateral and z-vertical) under actual working conditions according to the recommendations of ISO 2631-1. The results showed that LBP was more prevalent amongst forklift drivers than among non-drivers and driving postures in which the trunk is considerably twisted or bent forward associated with greatest risk. Furthermore, forklift drivers showed to be exposed to acceptable levels of vibration in the x- and y-directions (i.e., below the EU Physical Agents Directive on Vibration Exposure recommended action level—0.5 m/s 2), but not in the z-direction. There were indications that whole-body vibration acts associatively with other factors (not independently) to precipitate LBP.

  3. Parietal cortex coding of limb posture: in search of the body-schema.

    PubMed

    Parkinson, Amy; Condon, Laura; Jackson, Stephen R

    2010-09-01

    Computational theories of motor control propose that the brain uses 'forward' models of the body to ensure accurate control of movements. Forward 'dynamic' models are thought to generate an estimate of the next motor state for an upcoming movement: thereby providing a dynamic representation of the current postural configuration of the body that can be utilised during movement planning and execution. We used event-related functional magnetic resonance imaging [fMRI] to investigate brain areas involved in maintaining and updating the postural representations of the upper limb that participate in the control of reaching movements. We demonstrate that the neural correlates for executing memory-guided reaching movements to unseen target locations that were defined by arm posture, are primarily within regions of the superior parietal lobule [SPL]: including an area of the medial SPL identified as the human homologue of the 'parietal reach region' [PRR]. Using effective connectivity analyses we show that signals that influence the BOLD response within this area originate within premotor areas of the frontal lobe, including premotor cortex and the supplementary motor area. These data are consistent with the view that the SPL maintains an up-to-date estimate of the current postural configuration of the arm that is used during the planning and execution of reaching movements.

  4. A functional-based segmentation of human body scans in arbitrary postures.

    PubMed

    Werghi, Naoufel; Xiao, Yijun; Siebert, Jan Paul

    2006-02-01

    This paper presents a general framework that aims to address the task of segmenting three-dimensional (3-D) scan data representing the human form into subsets which correspond to functional human body parts. Such a task is challenging due to the articulated and deformable nature of the human body. A salient feature of this framework is that it is able to cope with various body postures and is in addition robust to noise, holes, irregular sampling and rigid transformations. Although whole human body scanners are now capable of routinely capturing the shape of the whole body in machine readable format, they have not yet realized their potential to provide automatic extraction of key body measurements. Automated production of anthropometric databases is a prerequisite to satisfying the needs of certain industrial sectors (e.g., the clothing industry). This implies that in order to extract specific measurements of interest, whole body 3-D scan data must be segmented by machine into subsets corresponding to functional human body parts. However, previously reported attempts at automating the segmentation process suffer from various limitations, such as being restricted to a standard specific posture and being vulnerable to scan data artifacts. Our human body segmentation algorithm advances the state of the art to overcome the above limitations and we present experimental results obtained using both real and synthetic data that confirm the validity, effectiveness, and robustness of our approach.

  5. Theoretical optimization of usage of four-wheeled walker and body posture of elderly users for comfortable steady walking.

    PubMed

    Takanokura, Masato

    2008-01-01

    Usage of a four-wheeled walker and body posture of elderly users is optimized by a two-dimensional statics model for comfortable steady walking. Analytical results suggest that fundamentals of body posture for comfortable walking should be as upright as possible. However, usage of the walker varies with exercise capabilities of elderly users. Users with high capabilities should use a higher handgrip for maintaining upright posture. Stooping users with low capabilities should use a lower handgrip, should maintain an erect trunk as much as possible, and should push the handgrip downward by leaning their upper body on the walker.

  6. Relations of the morphological characteristic latent structure and body posture indicators in children aged seven to nine years.

    PubMed

    Pausić, Jelena; Cavala, Marijana; Katić, Ratko

    2006-09-01

    With the aim of determining the connection between the indicators of body posture and latent structure of morphological variables in children aged 7 and 8 years, first and second grade of primary school, a set of 17 morphological measures and 12 body posture indicators were longitudinally applied to a sample of 110 boys and 114 girls. The latent structure of morphological variables in both sexes was defined by three factors but at a different order of significance: in boys, the order was longitudinal dimensionality, voluminosity, mass and subcutaneous fat tissue and transverse dimensionality, whereas in girls the order was voluminosity, mass and subcutaneous fat tissue, longitudinal dimensionality and transverse dimensionality. The latent structure of torax body posture indicator was defined by two factors, the status of body posture of the rear part of the thorax, and status of the body posture of the front part of the thorax. The results obtained by canonical correlation analysis between predictive variables, morphological latent structure and criterion variables, latent structure of thorax body posture indicators with two posture indicators of the chest and one of the foot status, showed two important pairs of canonical roots on each measurement, suggesting a significant association between these two sets of parameters.

  7. Do malocclusion and Helkimo Index ≥ 5 correlate with body posture?

    PubMed

    Perillo, L; Femminella, B; Farronato, D; Baccetti, T; Contardo, L; Perinetti, G

    2011-04-01

    Whether there are correlations between the stomatognathic system and body posture remains controversial. Here, we have investigated whether malocclusal traits and having a Helkimo Index ≥ 5 show detectable correlations with body-posture alterations in children and young adults. A total of 1178 11- to 19-year-old subjects were divided into four groups: (i) controls; (ii) malocclusion; (iii) Helkimo Index ≥ 5 and (iv) malocclusion + Helkimo Index ≥ 5. Dental occlusion assessment included the following: overbite, overjet, posterior crossbite, scissorbite, mandibular crowding and dental class. Subsequently, body-posture assessments were performed through static analyses of body inclination and trunk asymmetry, and according to the dynamic Fukuda stepping test. Univariate and multivariate statistical analyses were performed. Although at the univariate level both the trunk asymmetry and Fukuda stepping test showed significant differences among the groups, the multivariate level revealed that age and gender were mostly responsible for this. The only significant correlation that was seen was for the malocclusion + Helkimo Index ≥ 5 group: these subjects had a positive (worse) trunk asymmetry and a negative (better) Fukuda stepping test performance. At the further multivariate analyses of each single malocclusal trait ⁄Helkimo Index ≥ 5 (irrespective of the groups), only an increased overbite showed a statistically significant association with a slightly better Fukuda stepping test performance. Given the small number of significant associations seen and their limited entities, this study does not support the existence of clinically relevant correlations for malocclusal traits and Helkimo Index ≥ 5 with body posture in children and young adults.

  8. Measurement of three-dimensional posture and trajectory of lower body during standing long jumping utilizing body-mounted sensors.

    PubMed

    Ibata, Yuki; Kitamura, Seiji; Motoi, Kosuke; Sagawa, Koichi

    2013-01-01

    The measurement method of three-dimensional posture and flying trajectory of lower body during jumping motion using body-mounted wireless inertial measurement units (WIMU) is introduced. The WIMU is composed of three-dimensional (3D) accelerometer and gyroscope of two kinds with different dynamic range and one 3D geomagnetic sensor to adapt to quick movement. Three WIMUs are mounted under the chest, right thigh and right shank. Thin film pressure sensors are connected to the shank WIMU and are installed under right heel and tiptoe to distinguish the state of the body motion between grounding and jumping. Initial and final postures of trunk, thigh and shank at standing-still are obtained using gravitational acceleration and geomagnetism. The posture of body is determined using the 3D direction of each segment updated by the numerical integration of angular velocity. Flying motion is detected from pressure sensors and 3D flying trajectory is derived by the double integration of trunk acceleration applying the 3D velocity of trunk at takeoff. Standing long jump experiments are performed and experimental results show that the joint angle and flying trajectory agree with the actual motion measured by the optical motion capture system. PMID:24110831

  9. Evaluation of Postural Asymmetry and Gross Joint Mobility in Elite Female Volleyball Athletes

    PubMed Central

    Vařeková, Renata; Vařeka, Ivan; Janura, Miroslav; Svoboda, Zdenek; Elfmark, Milan

    2011-01-01

    The purpose of the study was to evaluate marked postural asymmetry and gross joint mobility in elite female volleyball athletes. Sixty-two Czech and Slovak elite female volleyball athletes (age 20.7±2.03 years, body mass 71.1±6.18 kg, body height 1.804±.0618 m, BMI 21.8±1.78) were examined by an experienced rehabilitation physician. The set of tests included the frontal posture gross examination, the forward bending test from the standing position and the deep squat test. The spiking hand and the presence of any lower extremity injury were estimated by interview. The proportion test, Mann-Whitney test and t-test were used to evaluate statistical significance (p<0.05). Fifty subjects (80.6%) exhibited “typical” frontal plane posture in which the acromion, scapula and the iliac crest were in a higher position on the left side than on the right, significantly more frequently than all the other patterns (proportion test, p<0.0001). Ninety-eight percent of the subjects with the “LLL pattern” preferred the right arm for spiking (proportion test, p<0.0001). Forty-one subjects (66%) exhibited hypermobility in the forward bending test, significantly more frequently than twenty-one subjects (34%) with normal results (proportion test, p=0.0003). Thirty-four subjects (55%) did not succeed in the deep squat test and hypermobility in the forward bending test paradoxically prevailed in them significantly (proportion test, p=0.004). Restriction in the deep squat test was not linked to obesity, age (t-test, p=0.081) nor knee (proportion test, p=0.85) and ankle injury (Mann-Whitney test, p=0.36) in the past. Significant prevalence of hypermobility in the forward bending test was not surprising because of general body composition and the performance of regular stretching exercises in elite female volleyball athletes. On the other hand, surprisingly, more than half of the subjects did not succeed in the deep squat test. The cause of poor results in the deep squat test

  10. Evaluation of postural asymmetry and gross joint mobility in elite female volleyball athletes.

    PubMed

    Vařeková, Renata; Vařeka, Ivan; Janura, Miroslav; Svoboda, Zdenek; Elfmark, Milan

    2011-09-01

    The purpose of the study was to evaluate marked postural asymmetry and gross joint mobility in elite female volleyball athletes. Sixty-two Czech and Slovak elite female volleyball athletes (age 20.7±2.03 years, body mass 71.1±6.18 kg, body height 1.804±.0618 m, BMI 21.8±1.78) were examined by an experienced rehabilitation physician. The set of tests included the frontal posture gross examination, the forward bending test from the standing position and the deep squat test. The spiking hand and the presence of any lower extremity injury were estimated by interview. The proportion test, Mann-Whitney test and t-test were used to evaluate statistical significance (p<0.05). Fifty subjects (80.6%) exhibited "typical" frontal plane posture in which the acromion, scapula and the iliac crest were in a higher position on the left side than on the right, significantly more frequently than all the other patterns (proportion test, p<0.0001). Ninety-eight percent of the subjects with the "LLL pattern" preferred the right arm for spiking (proportion test, p<0.0001). Forty-one subjects (66%) exhibited hypermobility in the forward bending test, significantly more frequently than twenty-one subjects (34%) with normal results (proportion test, p=0.0003). Thirty-four subjects (55%) did not succeed in the deep squat test and hypermobility in the forward bending test paradoxically prevailed in them significantly (proportion test, p=0.004). Restriction in the deep squat test was not linked to obesity, age (t-test, p=0.081) nor knee (proportion test, p=0.85) and ankle injury (Mann-Whitney test, p=0.36) in the past. Significant prevalence of hypermobility in the forward bending test was not surprising because of general body composition and the performance of regular stretching exercises in elite female volleyball athletes. On the other hand, surprisingly, more than half of the subjects did not succeed in the deep squat test. The cause of poor results in the deep squat test could be due

  11. The dominant foot affects the postural control mechanism: examination by body tracking test

    PubMed Central

    Ikemiyagi, Fuyuko; Ikemiyagi, Yoshihiro; Tanaka, Tositake; Yamamoto, Masahiko; Suzuki, Mitsuya

    2014-01-01

    Conclusion The antero-posterior (AP) body tracking test (BTT) showed that the dominant foot could affect the tilt angle of the sway movement, delineated by primary component analysis. Differences associated with the dominant foot could represent the difference in space perception of each person. Objectives To examine whether the dominant foot could affect the postural control mechanism using the BTT. Methods Ninety-seven healthy participants enrolled in the study were classified into right-foot and left-foot dominance groups, and their performances were compared. For the BTT, each participant stood on a stabilometer and caught the movement of a visual target moving vertically (anterior-posterior) or horizontally by the center of pressure movement, displayed on a 14-inch screen monitor at 100 cm in front of the subject. The mean displacement angle of the obtained stabilogram was evaluated by principal component analysis. Results The AP BTT in the right-foot dominance group showed a clockwise tilt with a mean displacement angle of 3.022 ± 3.761°, whereas the group with left-foot dominance had a modest counter-clockwise tilt with a mean displacement angle of –0.694 ± 4.497°. This difference was found to be significant by the independent t test (p < 0.0001). In the lateral BTT, the mean displacement angles were not significant. PMID:25252704

  12. Correlations between postural stability and strength of lower body extremities of women population living in long-term care facilities.

    PubMed

    Wiacek, Magdalena; Hagner, Wojciech; Hagner-Derengowska, Magdalena; Bluj, Barbara; Drozd, Monika; Czereba, Jolanta; Zubrzycki, Igor Z

    2009-01-01

    The present study was aimed at analyzing correlation between strength of lower body extremities and postural stability in function of age. A pool of 180 women divided into 6 age groups (65-69, 70-74, 75-79, 80-84, 85-89 and 90-94 years) was examined. They all were informed-consent participants. The results suggest that age is negatively correlated with lower body strength and positively correlated with decrease of postural balance. There is also an exponential correlation between the strength of lower body part and postural balance. The conclusion was derived that postural stability is at least partially controlled by the strength of lower body. The age of 75 in women population seems to be a threshold above which the neurodegenerative and muscle degeneration processes are responsible for significant increase of risk of fall.

  13. Relationship between functional movement screen scores, core strength, posture, and body mass index in school children in Moldova.

    PubMed

    Mitchell, Ulrike H; Johnson, A Wayne; Adamson, Brynn

    2015-05-01

    The assessment of functionality should include parameters that consider postural control, limb asymmetries, range of motion limitations, proprioceptive deficits, and pain. An increasingly popular battery of tests, the Functional Movement Screen (FMS), is purported to assess the above named parameters. The purpose of our study was twofold: (a) to report differences in total FMS scores in children, provide preliminary normative reference values of each of the 7 individual FMS scores for both genders and report on asymmetries and (b) to evaluate the relationship between total FMS scores, age, body mass index (BMI), core strength/stability, and postural angles to explore the possibility of using the FMS in the assessment of children's functional fitness. Descriptive data on 77 children aged 8-11 years were collected. The children performed core strength/stability exercises. Photographs were taken from a lateral view for later calculation of postural angles. The children performed the FMS while being videotaped for later review. The average total FMS score (of 21) was 14.9 (+1.9), and BMI was 16.4 (+2.2). Static posture is not related to results of the FMS. Core strength was positively correlated to the total FMS score (r = 0.31; p = 0.006). Over 60% demonstrated at least 1 asymmetry. The individual test scores indicate that none of the test items is too difficult for the children. Based on the screen's correlation to core strength, and the fact that it identifies areas of asymmetry, we suggest to further investigate its possible use in the assessment of children's functional fitness.

  14. Evaluation of Novel EMG Biofeedback for Postural Correction During Computer Use.

    PubMed

    Gaffney, Brecca M; Maluf, Katrina S; Davidson, Bradley S

    2016-06-01

    Postural correction is an effective rehabilitation technique used to treat chronic neck and shoulder pain, and is aimed toward reducing the load on the surrounding muscles by adopting a neutral posture. The objective of this investigation was to evaluate the effectiveness of real-time high-density surface EMG (HDsEMG) biofeedback for postural correction during typing. Twenty healthy participants performed a typing task with two forms of postural feedback: (1) verbal postural coaching and (2) verbal postural coaching plus HDsEMG biofeedback. The interface used activity from two HDsEMG arrays placed over the trapezius designed to shift trapezius muscle activity inferiorly. The center of gravity across both arrays was used to quantify the spatial distribution of trapezius activity. Planar angles taken from upper extremity reflective markers quantified cervicoscapular posture. During the biofeedback condition, trapezius muscle activity was located 12.74 ± 3.73 mm more inferior, the scapula was 2.58 ± 1.18° more adducted and 0.23 ± 0.24° more depressed in comparison to verbal postural coaching alone. The results demonstrate the short-term effectiveness of a real-time HDsEMG biofeedback intervention to achieve postural correction, and may be more effective at creating an inferior shift in trapezius muscle activity in comparison to verbal postural coaching alone. PMID:26718205

  15. Effect of lower-body positive pressure on postural fluid shifts in men

    NASA Technical Reports Server (NTRS)

    Hinghofer-Szalkay, H.; Kravik, S. E.; Greenleaf, J. E.

    1988-01-01

    The effect of the lower-body positive pressure (LBPP) on the orthostatic fluid and protein shifts were investigated in five men during combined tilt-table/antigravity suit inflation and deflation experiments. Changes in the mass densities of venous blood and plasma were measured and the values were used to calculate the densities of erythrocytes, whole-body blood, and shifted fluid. It was found that the application of 60 mm Hg LBPP during 60-deg head-up tilt prevented about half of the postural hemoconcentration occurring during passive head-up tilt.

  16. Body position alters human resting-state: Insights from multi-postural magnetoencephalography.

    PubMed

    Thibault, Robert T; Lifshitz, Michael; Raz, Amir

    2016-09-01

    Neuroimaging researchers tacitly assume that body-position scantily affects neural activity. However, whereas participants in most psychological experiments sit upright, many modern neuroimaging techniques (e.g., fMRI) require participants to lie supine. Sparse findings from electroencephalography and positron emission tomography suggest that body position influences cognitive processes and neural activity. Here we leverage multi-postural magnetoencephalography (MEG) to further unravel how physical stance alters baseline brain activity. We present resting-state MEG data from 12 healthy participants in three orthostatic conditions (i.e., lying supine, reclined at 45°, and sitting upright). Our findings demonstrate that upright, compared to reclined or supine, posture increases left-hemisphere high-frequency oscillatory activity over common speech areas. This proof-of-concept experiment establishes the feasibility of using MEG to examine the influence of posture on brain dynamics. We highlight the advantages and methodological challenges inherent to this approach and lay the foundation for future studies to further investigate this important, albeit little-acknowledged, procedural caveat. PMID:26409469

  17. Body position alters human resting-state: Insights from multi-postural magnetoencephalography.

    PubMed

    Thibault, Robert T; Lifshitz, Michael; Raz, Amir

    2016-09-01

    Neuroimaging researchers tacitly assume that body-position scantily affects neural activity. However, whereas participants in most psychological experiments sit upright, many modern neuroimaging techniques (e.g., fMRI) require participants to lie supine. Sparse findings from electroencephalography and positron emission tomography suggest that body position influences cognitive processes and neural activity. Here we leverage multi-postural magnetoencephalography (MEG) to further unravel how physical stance alters baseline brain activity. We present resting-state MEG data from 12 healthy participants in three orthostatic conditions (i.e., lying supine, reclined at 45°, and sitting upright). Our findings demonstrate that upright, compared to reclined or supine, posture increases left-hemisphere high-frequency oscillatory activity over common speech areas. This proof-of-concept experiment establishes the feasibility of using MEG to examine the influence of posture on brain dynamics. We highlight the advantages and methodological challenges inherent to this approach and lay the foundation for future studies to further investigate this important, albeit little-acknowledged, procedural caveat.

  18. Effect of table top slope and height on body posture and muscular activity pattern.

    PubMed

    Hassaïne, M; Hamaoui, A; Zanone, P-G

    2015-04-01

    The objective of this study was to assess the effect of table top slope and height on body posture and muscular activity pattern. Twelve asymptomatic participants performed a 5-min reading task while sitting, in six experimental conditions manipulating the table top slope (20° backward slope, no slope) and its height (low, medium, up). EMGs recordings were taken on 9 superficial muscles located at the trunk and shoulder level, and the angular positions of the head, trunk and pelvis were assessed using an inertial orientation system. Results revealed that the sloping table top was associated with a higher activity of deltoideus pars clavicularis (P<0.05) and a smaller flexion angle of the head (P<0.05). A tentative conclusion is that a sloping table top induces a more erect posture of the head and the neck, but entails an overload of the shoulder, which might be harmful on the long run. PMID:25267452

  19. Trunk postures and upper-body muscle activations during physically demanding wildfire suppression tasks.

    PubMed

    Neesham-Smith, Daniel; Aisbett, Brad; Netto, Kevin

    2014-01-01

    This study examined the trunk postures and upper-body muscle activations during four physically demanding wildfire suppression tasks. Bilateral, wireless surface electromyography was recorded from the trapezius and erector spinae muscles of nine experienced, wildfire fighters. Synchronised video captured two retroreflective markers to allow for quantification of two-dimensional sagittal trunk flexion. In all tasks, significantly longer time was spent in the mild and severe trunk flexion (p ≤ 0.002) compared to the time spent in a neutral posture. Mean and peak muscle activation in all tasks exceeded previously established safe limits. These activation levels also significantly increased through the performance of each task (p < 0.001). The results suggest that the wildfire suppression tasks analysed impose significant musculoskeletal demand on firefighters. Fire agencies should consider developing interventions to reduce the exposure of their personnel to these potentially injurious musculoskeletal demands.

  20. Trunk postures and upper-body muscle activations during physically demanding wildfire suppression tasks.

    PubMed

    Neesham-Smith, Daniel; Aisbett, Brad; Netto, Kevin

    2014-01-01

    This study examined the trunk postures and upper-body muscle activations during four physically demanding wildfire suppression tasks. Bilateral, wireless surface electromyography was recorded from the trapezius and erector spinae muscles of nine experienced, wildfire fighters. Synchronised video captured two retroreflective markers to allow for quantification of two-dimensional sagittal trunk flexion. In all tasks, significantly longer time was spent in the mild and severe trunk flexion (p ≤ 0.002) compared to the time spent in a neutral posture. Mean and peak muscle activation in all tasks exceeded previously established safe limits. These activation levels also significantly increased through the performance of each task (p < 0.001). The results suggest that the wildfire suppression tasks analysed impose significant musculoskeletal demand on firefighters. Fire agencies should consider developing interventions to reduce the exposure of their personnel to these potentially injurious musculoskeletal demands. PMID:24365452

  1. Long-range tactile masking occurs in the postural body schema.

    PubMed

    D'Amour, Sarah; Harris, Laurence R

    2016-02-01

    Long-range tactile masking has been reported between mirror symmetric body locations. This suggests a general principle of contralateral inhibition between corresponding points on each side of the body that may serve to enhance distinguishing touches on the two halves of the body. Do such effects occur before or after posture is added to the body schema? Here, we address this question by exploring the effect of arm position on long-range tactile masking. The influence of arm position was investigated using different positions of both the test and masking arms. Tactile sensitivity was measured on one forearm, while vibrotactile-masking stimulation was applied to the opposite arm or to a control site on the shoulder. No difference was found in sensitivity when test arm position was varied. Physical contact between the arms significantly increased the effectiveness of a masking stimulus applied to the other arm. Long-range masking between the arms was strongest when the arms were held parallel to each other and was abolished if the position of either the test arm or the masking arm was moved from this position. Modulation of the effectiveness of masking by the position of both the test and masking arms suggests that these effects occur after posture information is added to the body's representation in the brain. PMID:26553240

  2. Long-range tactile masking occurs in the postural body schema.

    PubMed

    D'Amour, Sarah; Harris, Laurence R

    2016-02-01

    Long-range tactile masking has been reported between mirror symmetric body locations. This suggests a general principle of contralateral inhibition between corresponding points on each side of the body that may serve to enhance distinguishing touches on the two halves of the body. Do such effects occur before or after posture is added to the body schema? Here, we address this question by exploring the effect of arm position on long-range tactile masking. The influence of arm position was investigated using different positions of both the test and masking arms. Tactile sensitivity was measured on one forearm, while vibrotactile-masking stimulation was applied to the opposite arm or to a control site on the shoulder. No difference was found in sensitivity when test arm position was varied. Physical contact between the arms significantly increased the effectiveness of a masking stimulus applied to the other arm. Long-range masking between the arms was strongest when the arms were held parallel to each other and was abolished if the position of either the test arm or the masking arm was moved from this position. Modulation of the effectiveness of masking by the position of both the test and masking arms suggests that these effects occur after posture information is added to the body's representation in the brain.

  3. Upper body balance control strategy during continuous 3D postural perturbation in young adults.

    PubMed

    Amori, V; Petrarca, M; Patané, F; Castelli, E; Cappa, P

    2015-01-01

    We explored how changes in vision and perturbation frequency impacted upright postural control in healthy adults exposed to continuous multiaxial support-surface perturbation. Ten subjects were asked to maintain equilibrium in standing stance with eyes open (EO) and eyes closed (EC) during sinusoidal 3D rotations at 0.25 (L) and 0.50 Hz (H). We measured upper-body kinematics--head, trunk, and pelvis--and analyzed differences in horizontal displacements and roll, pitch, and yaw sways. The presence of vision significantly decreased upper-body displacements in the horizontal plane, especially at the head level, while in EC the head was the most unstable segment. H trials produced a greater segment stabilization compared to L ones in EO and EC. Analysis of sways showed that in EO participants stabilized their posture by reducing the variability of trunk angles; in H trials a sway decrease for the examined segments was observed in the yaw plane and, for the pelvis only, in the pitch plane. Our results suggest that, during continuous multiaxial perturbations, visual information induced: (i) in L condition, a continuous reconfiguration of multi-body-segments orientation to follow the perturbation; (ii) in H condition, a compensation for the ongoing perturbation. These findings were not confirmed in EC where the same strategy--that is, the use of the pelvis as a reference frame for the body balance was adopted both in L and H.

  4. Quantification of ln-Flight Physical Changes: Anthropometry and Neutral Body Posture

    NASA Technical Reports Server (NTRS)

    Young, K. S.; Amick, R.; Rajulu, S.

    2016-01-01

    Currently, NASA does not have sufficient in-flight anthropometric data to assess the impact of changes in body shape and size. For developing future planetary and reduced-gravity suits, NASA needs to quantify the impacts of microgravity on anthropometry and body posture to ensure optimal crew performance, fit, and comfort. To obtain data on these changes, circumference, length, height, breadth, and depth for body segments (chest, waist, bicep, thigh, calf) from astronauts for preflight, in-flight, and post-flight conditions needs to be collected. Once these data have been collected, pre-flight, in-flight, and post-flight anthropometric values will be compared, yielding microgravity factors. The neutral body posture (NBP) will also be measured, to determine body posture (joint angle) changes between subjects throughout the duration of a mission. Data collection, starting with Increments 37/38, is still in progress but has been completed for 6 out of 9 subjects. NASA suit engineers and NASA's Extravehicular Activity (EVA) Project Office have identified that suit fit in microgravity could become an issue. It has been noted that crewmembers often need to adjust their suit sizing once they are in orbit. This adjustment could be due to microgravity effects on anthropometry and postural changes, and is necessary to ensure optimal crew performance, fit, and comfort in space. To date, the only data collected to determine the effects of microgravity on physical human changes were collected during Skylab 4, the Apollo-Soyuz Test Project (ASTP), Space Shuttle mission STS-57, and a recent HRP study on seated height changes due to spinal elongation (Spinal Elongation, Master Task List [MTL] #221). The Skylab 4, ASTP, and the STS-57 studies found that, according to photographs, a distinct NBP exists. The still photographs showed a distinguishable posture with the arms raised and the shoulders abducted; in addition, the knees are flexed, with noticeable hip flexion, and the foot

  5. Quantification of In-flight Physical Changes: Anthropometry and Neutral Body Posture

    NASA Technical Reports Server (NTRS)

    Young, K. S.; Reid, C. R.; Rajulu, S.

    2014-01-01

    Currently, NASA does not have sufficient in-flight anthropometric data gathered to assess the impact of physical body shape and size changes on suit sizing. For developing future planetary and reduced gravity suits, NASA needs to quantify the impacts of microgravity on anthropometry, body posture, and neutral body postures (NBP) to ensure optimal crew performance, fit, and comfort. To obtain these impacts, anthropometric data, circumference, length, height, breadth, and depth for body segments (i.e. chest, waist, bicep, thigh, calf) from astronauts for pre, in-, and postflight conditions needs to be collected. Once this data has been collected, a comparison between pre, in-, and postflight anthropometric values will be analyzed, yielding microgravity factors. The NBP will be used to determined body posture (joint angle) changes between subjects throughout the duration of a mission. Data collection, starting with Increments 37/38, is still in progress with the completion of 3 out of 12 subjects. NASA suit engineers and NASA's Extravehicular Activity (EVA) Project Office have identified that suit fit in microgravity could become an issue. It has been noted that crewmembers often need to adjust their suit sizing once they are in orbit. This adjustment could be due to microgravity effects on anthropometry and postural changes, and is necessary to ensure optimal crew performance, fit, and comfort in space. To date, the only data collected to determine the effects of microgravity on physical human changes have been during Skylab, STS-57, and a recent HRP study on seated height changes due to spinal elongation (Spinal Elongation, Master Task List [MTL] #221). The Skylab and the STS-57 studies found that there is a distinct neutral body posture (NBP) based on photographs. The still photographs showed that there is a distinguishable posture with the arms raised and the shoulder abducted; and, in addition, the knees were flexed with noticeable hip flexion and the foot

  6. Control of sway using vibrotactile feedback of body tilt in patients with moderate and severe postural control deficits.

    PubMed

    Wall, C; Kentala, E

    2005-01-01

    We evaluated the effect of the vibrotactile display of body tilt upon the postural stability of vestibulopathic subjects during standing. Two groups were studied: those with moderate and with severe deficits as defined by postural stability test scores. They were studied under conditions of distorted sensory input, and during anterior-posterior perturbations. Seventeen subjects, with uni- or bilateral vestibular deficits, as determined by electronystagmography and vertical axis rotation, were tested using Equitest computerized dynamic posturography (CDP). Based on their performance on the CDP they were divided into two groups having either moderate (nine subjects) or severe (eight subjects) postural control deficits. Their anterior-posterior (A/P) body motion at the waist was measured with a micromechanical rate gyroscope and a linear accelerometer. The resulting tilt estimate was displayed by a vibrotactile array attached to the torso. The vibration served as a tilt feedback to the subject. The subject's performance was evaluated using the root-mean-square (RMS) of both the A/P body motion and center-of-pressure (CoP) estimates. Sensory distortions were introduced using the Equitest Sensory Organization Tests (SOT). These tests are designed to distort A/P sensory inputs while standing. The SOT 5 distorts proprioceptive information about ankle joint movement, while the subject stands eyes-closed on a moving support platform that measures foot pressure. The SOT 6 adds distorted visual information about body movement instead of testing with eyes closed. Perturbations were introduced using the Equitest Motor Control Tests (MCT). These move the support platform forward or backward with small, medium and large displacements in the horizontal plane while measuring subjects' foot pressure responses. We used the medium and large backward tests. Vibrotactile display of body tilt reduced the subjects' A/P sway and improved their balance. The finding was more evident for

  7. Revisiting the Body-Schema Concept in the Context of Whole-Body Postural-Focal Dynamics

    PubMed Central

    Morasso, Pietro; Casadio, Maura; Mohan, Vishwanathan; Rea, Francesco; Zenzeri, Jacopo

    2015-01-01

    The body-schema concept is revisited in the context of embodied cognition, further developing the theory formulated by Marc Jeannerod that the motor system is part of a simulation network related to action, whose function is not only to shape the motor system for preparing an action (either overt or covert) but also to provide the self with information on the feasibility and the meaning of potential actions. The proposed computational formulation is based on a dynamical system approach, which is linked to an extension of the equilibrium-point hypothesis, called Passive Motor Paradigm: this dynamical system generates goal-oriented, spatio-temporal, sensorimotor patterns, integrating a direct and inverse internal model in a multi-referential framework. The purpose of such computational model is to operate at the same time as a general synergy formation machinery for planning whole-body actions in humanoid robots and/or for predicting coordinated sensory–motor patterns in human movements. In order to illustrate the computational approach, the integration of simultaneous, even partially conflicting tasks will be analyzed in some detail with regard to postural-focal dynamics, which can be defined as the fusion of a focal task, namely reaching a target with the whole-body, and a postural task, namely maintaining overall stability. PMID:25741274

  8. Revisiting the body-schema concept in the context of whole-body postural-focal dynamics.

    PubMed

    Morasso, Pietro; Casadio, Maura; Mohan, Vishwanathan; Rea, Francesco; Zenzeri, Jacopo

    2015-01-01

    The body-schema concept is revisited in the context of embodied cognition, further developing the theory formulated by Marc Jeannerod that the motor system is part of a simulation network related to action, whose function is not only to shape the motor system for preparing an action (either overt or covert) but also to provide the self with information on the feasibility and the meaning of potential actions. The proposed computational formulation is based on a dynamical system approach, which is linked to an extension of the equilibrium-point hypothesis, called Passive Motor Paradigm: this dynamical system generates goal-oriented, spatio-temporal, sensorimotor patterns, integrating a direct and inverse internal model in a multi-referential framework. The purpose of such computational model is to operate at the same time as a general synergy formation machinery for planning whole-body actions in humanoid robots and/or for predicting coordinated sensory-motor patterns in human movements. In order to illustrate the computational approach, the integration of simultaneous, even partially conflicting tasks will be analyzed in some detail with regard to postural-focal dynamics, which can be defined as the fusion of a focal task, namely reaching a target with the whole-body, and a postural task, namely maintaining overall stability. PMID:25741274

  9. Revisiting the body-schema concept in the context of whole-body postural-focal dynamics.

    PubMed

    Morasso, Pietro; Casadio, Maura; Mohan, Vishwanathan; Rea, Francesco; Zenzeri, Jacopo

    2015-01-01

    The body-schema concept is revisited in the context of embodied cognition, further developing the theory formulated by Marc Jeannerod that the motor system is part of a simulation network related to action, whose function is not only to shape the motor system for preparing an action (either overt or covert) but also to provide the self with information on the feasibility and the meaning of potential actions. The proposed computational formulation is based on a dynamical system approach, which is linked to an extension of the equilibrium-point hypothesis, called Passive Motor Paradigm: this dynamical system generates goal-oriented, spatio-temporal, sensorimotor patterns, integrating a direct and inverse internal model in a multi-referential framework. The purpose of such computational model is to operate at the same time as a general synergy formation machinery for planning whole-body actions in humanoid robots and/or for predicting coordinated sensory-motor patterns in human movements. In order to illustrate the computational approach, the integration of simultaneous, even partially conflicting tasks will be analyzed in some detail with regard to postural-focal dynamics, which can be defined as the fusion of a focal task, namely reaching a target with the whole-body, and a postural task, namely maintaining overall stability.

  10. Participatory ergonomics and an evaluation of a low-cost improvement effect on cleaners' working posture.

    PubMed

    Kumar, Rupesh; Chaikumarn, Montakarn; Lundberg, Jan

    2005-01-01

    Cleaning is a highly physically demanding job with a high frequency of awkward postures and working environments as contributing risk factors. Participatory ergonomics is a method in which end-users take an active role in identifying risk factors and solutions. The aim of this study was to apply the participatory ergonomics method to identify cleaning problems and to evaluate the effect of a low-cost improvement on cleaners' working postures in an office environment. The results show that the cleaning problem was identified, and the low-cost ergonomics solution suggested by the cleaners was implemented. Thus an improved working environment reduced the number of awkward cleaning postures and the Ovako Working Posture Analysis System (OWAS) action category for floor mopping decreased. It can be concluded that working in an improved environment can lead to better working postures which, in turn, leads to the cleaners' better health and better cleaning results.

  11. Attribution of emotions to body postures: an independent component analysis study of functional connectivity in autism.

    PubMed

    Libero, Lauren E; Stevens, Carl E; Kana, Rajesh K

    2014-10-01

    The ability to interpret others' body language is a vital skill that helps us infer their thoughts and emotions. However, individuals with autism spectrum disorder (ASD) have been found to have difficulty in understanding the meaning of people's body language, perhaps leading to an overarching deficit in processing emotions. The current fMRI study investigates the functional connectivity underlying emotion and action judgment in the context of processing body language in high-functioning adolescents and young adults with autism, using an independent components analysis (ICA) of the fMRI time series. While there were no reliable group differences in brain activity, the ICA revealed significant involvement of occipital and parietal regions in processing body actions; and inferior frontal gyrus, superior medial prefrontal cortex, and occipital cortex in body expressions of emotions. In a between-group analysis, participants with autism, relative to typical controls, demonstrated significantly reduced temporal coherence in left ventral premotor cortex and right superior parietal lobule while processing emotions. Participants with ASD, on the other hand, showed increased temporal coherence in left fusiform gyrus while inferring emotions from body postures. Finally, a positive predictive relationship was found between empathizing ability and the brain areas underlying emotion processing in ASD participants. These results underscore the differential role of frontal and parietal brain regions in processing emotional body language in autism.

  12. Posture and mobility of the upper body quadrant and pulmonary function in COPD: an exploratory study *

    PubMed Central

    Morais, Nuno; Cruz, Joana; Marques, Alda

    2016-01-01

    ABSTRACT Background There is limited evidence regarding interactions between pulmonary (dys)function, posture, and mobility of the upper body quadrant in patients with chronic obstructive pulmonary disease (COPD). Objectives This exploratory study aimed to investigate whether postural alignment and mobility of the upper quadrant are related to changes in pulmonary function and compare such variables between patients with COPD and healthy individuals. Method Fifteen patients with COPD (67.93±9.71yrs) and 15 healthy controls (66.80±7.47yrs) participated. Pulmonary function (FEV1, FVC) was assessed with spirometry. Alignment and mobility of the head, thoracic spine, and shoulder were assessed using digital photographs. Pectoralis minor muscle (PmM) length and thoracic excursion were assessed with a measuring tape. Groups were compared and linear regression analyses were used to assess potential relationships between postural and mobility variables and pulmonary function. Results Patients with COPD were more likely to have a forward head position at maximal protraction (28.81±7.30º vs. 35.91±8.56º, p=0.02) and overall mobility of the head (21.81±10.42º vs. 13.40±7.84º, p=0.02) and a smaller range of shoulder flexion (136.71±11.91º vs. 149.08±11.58º, p=0.01) than controls. Patients’ non-dominant PmM length and maximal head protraction were predictors of FEV1 (r2 adjusted=0.34). These variables, together with the upper thoracic spine at maximal flexion and thoracic kyphosis at maximal extension, were predictors of FVC (r2 adjusted=0.68). Conclusion Our findings suggest that impaired pulmonary function is associated with muscle length and mobility adaptations. Further studies are needed to understand the underlying mechanisms and clinical value of these relationships. PMID:27556391

  13. A whole body postural loading simulation and assessment model for workplace analysis and design.

    PubMed

    Rebelo, Francisco; Correia da Silva, K; Karwowski, Waldemar

    2012-01-01

    This study reports on the development and validation of a new computer model for simulating human postures at work, and assessing the reaction forces and bending moments in 43 human articulation joints. The proposed model estimates the intradiscal pressure in the vertebral column in response to external loading forces encountered during human interactions with work objects or processes. The model was implemented in a self-contained interactive software package. The simulation results compare favorably with the reported experimental data, and provide reasonable confidence in the quality of the model. Its characteristics and its applications in evaluating physical task performance are also discussed. PMID:23294655

  14. The effect of body posture on long-range time-to-contact estimation.

    PubMed

    Baurès, Robin; Hecht, Heiko

    2011-01-01

    On Earth, gravity accelerates freely moving objects downward, whereas upward-moving objects are being decelerated. Do humans take internalised knowledge of gravity into account when estimating time-to-contact (TTC, the time remaining before the moving object reaches the observer)? To answer this question, we created a motion-prediction task in which participants saw the initial part of an object's trajectory moving on a collision course prior to an occlusion. Observers had to judge when the object would make contact with them. The visual scene was presented with a head-mounted display. Participants lay either supine (looking up) or prone (looking down), suggestive of the ball either rising up or falling down toward them. Results showed that body posture had a significant effect on time-to-contact estimation, but only when occlusion times were long (2.5 s). The effect was also rather small. This lack of immediacy in the posture effect suggests that TTC estimation is initially robust toward the effect of gravity, which comes to bear only as more time is allowed for post-processing of the visual information. PMID:21936296

  15. The effect of body posture on long-range time-to-contact estimation.

    PubMed

    Baurès, Robin; Hecht, Heiko

    2011-01-01

    On Earth, gravity accelerates freely moving objects downward, whereas upward-moving objects are being decelerated. Do humans take internalised knowledge of gravity into account when estimating time-to-contact (TTC, the time remaining before the moving object reaches the observer)? To answer this question, we created a motion-prediction task in which participants saw the initial part of an object's trajectory moving on a collision course prior to an occlusion. Observers had to judge when the object would make contact with them. The visual scene was presented with a head-mounted display. Participants lay either supine (looking up) or prone (looking down), suggestive of the ball either rising up or falling down toward them. Results showed that body posture had a significant effect on time-to-contact estimation, but only when occlusion times were long (2.5 s). The effect was also rather small. This lack of immediacy in the posture effect suggests that TTC estimation is initially robust toward the effect of gravity, which comes to bear only as more time is allowed for post-processing of the visual information.

  16. Photographic measurement of upper-body sitting posture of high school students: A reliability and validity study

    PubMed Central

    van Niekerk, Sjan-Mari; Louw, Quinette; Vaughan, Christopher; Grimmer-Somers, Karen; Schreve, Kristiaan

    2008-01-01

    Background All the reported measures of sitting posture, as well as photographs, have one flaw, as these measures are external to the body. These measures use calculations from external bony landmarks to estimate spinal posture, on the understanding that what is being measured externally reflects the shape, health and performance of structures of the underlying spine. Without a comparative measure of the relative position of the structures of the spine, the validity of any external spinal posture measure cannot be established. This paper reports on a study which tests the validity of photographs to measure adolescent sitting posture. Methods The study was conducted in a laboratory at the Department of Human Biology, University of Cape Town. A random sample of 40 adolescents were recruited from the Cape metropolitan schools, to detect differences of three degrees or more between the repeated measures of upright, normal or slouched posture (photographs) and between the posture photographs and LODOX measures. Eligible participants were healthy male and female subjects aged 15 or 16 years old, in Grade 10, and who were undertaking Computer or Computype studies at their schools. Two posture measurement tools were used in the study, namely: Photographs were taken using the Photographic Posture Analysis Method (PPAM) and Radiographs were taken using the LODOX (LODOX (Pty) Ltd) system. Subjects' posture was assessed in simulated computer workstations. The following angles were measured: the sagittal head angle, cervical angle, protraction/retraction angle, arm angle and the thoracic angle. Results Data from 39 subjects (19 males, 20 females) was used for analysis (17 15-year-olds (7 boys and 10 girls), 22 16-year-olds (12 boys and 10 girls)). All but one photographic angle showed moderate to good correlation with the LODOX angles (Pearson r values 0.67–0.95) with the exception being the shoulder protraction/retraction angle Pearson r values. Bland Altman limits of

  17. Reliability and validity of the Microsoft Kinect for evaluating static foot posture

    PubMed Central

    2013-01-01

    Background The evaluation of foot posture in a clinical setting is useful to screen for potential injury, however disagreement remains as to which method has the greatest clinical utility. An inexpensive and widely available imaging system, the Microsoft Kinect™, may possess the characteristics to objectively evaluate static foot posture in a clinical setting with high accuracy. The aim of this study was to assess the intra-rater reliability and validity of this system for assessing static foot posture. Methods Three measures were used to assess static foot posture; traditional visual observation using the Foot Posture Index (FPI), a 3D motion analysis (3DMA) system and software designed to collect and analyse image and depth data from the Kinect. Spearman’s rho was used to assess intra-rater reliability and concurrent validity of the Kinect to evaluate foot posture, and a linear regression was used to examine the ability of the Kinect to predict total visual FPI score. Results The Kinect demonstrated moderate to good intra-rater reliability for four FPI items of foot posture (ρ = 0.62 to 0.78) and moderate to good correlations with the 3DMA system for four items of foot posture (ρ = 0.51 to 0.85). In contrast, intra-rater reliability of visual FPI items was poor to moderate (ρ = 0.17 to 0.63), and correlations with the Kinect and 3DMA systems were poor (absolute ρ = 0.01 to 0.44). Kinect FPI items with moderate to good reliability predicted 61% of the variance in total visual FPI score. Conclusions The majority of the foot posture items derived using the Kinect were more reliable than the traditional visual assessment of FPI, and were valid when compared to a 3DMA system. Individual foot posture items recorded using the Kinect were also shown to predict a moderate degree of variance in the total visual FPI score. Combined, these results support the future potential of the Kinect to accurately evaluate static foot posture in a clinical

  18. Effects Related to Random Whole-Body Vibration and Posture on a Suspended Seatwith and Without Backrest

    NASA Astrophysics Data System (ADS)

    HINZ, B.; SEIDEL, H.; MENZEL, G.; BLÜTHNER, R.

    2002-05-01

    WBV-exposures are often linked with forced postures as prolonged sitting, bent forward sitting, or sitting without a backrest. No quantitative data are available to describe the exposure-effect relationships for different conditions of seating, posture, and the biological variability of workers. Experiments and subsequent predictions of forces acting within the spine during WBV can help to improve the assessment of the health risk. An experimental study was performed with 39 male subjects sitting on a suspension seat with or with no backrest contact. They were exposed to random whole-body vibration with a weighted r.m.s. value of 0·6 m/s2 at a relaxed or a forward bending posture. A two-dimensional finite element model was used for the calculation of the internal spinal load. The model simulates the human response on a suspension driver seat. Individual exposure conditions were considered by including the transfer functions between the seat cushion and the seat base as well as between the backrest and the seat base for the calculation of the vibration input to the buttocks and to the back respectively. The average peak seat transmissibility was higher for the seat with the backrest, but the peak seat-to-head transmissibility was higher for the seat without the backrest for both postures. The peak transmissibilities between the accelerations at the seat base and the compressive forces at L5/S1 were highest for the seat without the backrest during the bending posture. Various biological effects can result from identical exposures combined with different backrest contact and postures. The backrest contact and posture conditions should not be neglected in the assessment of health risk caused by whole-body vibration.

  19. Using frequency analysis to improve the precision of human body posture algorithms based on Kalman filters.

    PubMed

    Olivares, Alberto; Górriz, J M; Ramírez, J; Olivares, G

    2016-05-01

    With the advent of miniaturized inertial sensors many systems have been developed within the last decade to study and analyze human motion and posture, specially in the medical field. Data measured by the sensors are usually processed by algorithms based on Kalman Filters in order to estimate the orientation of the body parts under study. These filters traditionally include fixed parameters, such as the process and observation noise variances, whose value has large influence in the overall performance. It has been demonstrated that the optimal value of these parameters differs considerably for different motion intensities. Therefore, in this work, we show that, by applying frequency analysis to determine motion intensity, and varying the formerly fixed parameters accordingly, the overall precision of orientation estimation algorithms can be improved, therefore providing physicians with reliable objective data they can use in their daily practice.

  20. The Influence of Motor Imagery on Postural Sway: Differential Effects of Type of Body Movement and Person Perspective.

    PubMed

    Stins, John F; Schneider, Iris K; Koole, Sander L; Beek, Peter J

    2015-01-01

    The present study examined the differential effects of kinesthetic imagery (first person perspective) and visual imagery (third person perspective) on postural sway during quiet standing. Based on an embodied cognition perspective, the authors predicted that kinesthetic imagery would lead to activations in movement-relevant motor systems to a greater degree than visual imagery. This prediction was tested among 30 participants who imagined various motor activities from different visual perspectives while standing on a strain gauge plate. The results showed that kinesthetic imagery of lower body movements, but not of upper body movements, had clear effects on postural parameters (sway path length and frequency contents of sway). Visual imagery, in contrast, had no reliable effects on postural activity. We also found that postural effects were not affected by the vividness of imagery. The results suggest that during kinesthetic motor imagery participants partially simulated (re-activated) the imagined movements, leading to unintentional postural adjustments. These findings are consistent with an embodied cognition perspective on motor imagery.

  1. Body Posture Angle Affects the Physiological Indices of Patients With Liver Cirrhosis Ascites.

    PubMed

    Hsu, Wen-chuan; Ho, Lun-hui; Lin, Mei-hsiang; Chiu, Hsiu-ling

    2016-01-01

    The study objective was to compare the effect of different angles of lying positions on the physiological indices of patients with cirrhosis ascites. Chronic liver disease and cirrhosis were ranked 9th among the top 10 causes of death. Ascites is the most common cirrhosis comorbidity. Body posture can affect pulmonary ventilation and arterial oxygen partial pressure, making it an important clinical nursing intervention significantly affecting patient recovery. This was a quasi-experimental study design. From a medical center in Taiwan, 252 patients with cirrhosis ascites were recruited. Subjects were randomly divided into three groups by bed angle: 15°, 30°, and 45°. Physiological indices were measured at 5, 10, 15, 20, 25, and 30 minutes to determine any changes in heart rate, respiration rate, and oxygenation saturation. Data analysis included descriptive statistics and the generalized estimating equation for statistical analysis with significance set at α= 0.05. After controlling for confounding variables, the three groups differed significantly in heart rate at 20, 25, and 30 minutes, oxygenation saturations at 15 and 20 minutes, and respiration rate at 5 and 10 minutes (α< 0.05). Body posture can affect pulmonary ventilation and arterial oxygen partial pressure and is thus an important clinical nursing intervention that significantly affects the recovery of patients. When caring for patients with cirrhosis ascites, nurses should help patients to choose the most comfortable angle for them with no particular restrictions. Our results can be used to guide nurses in making a plan for health education and nursing that improves the quality of care for patients with chronic liver disease and cirrhosis patients with ascites. PMID:27070794

  2. Sagittal jaw position in relation to body posture in adult humans – a rasterstereographic study

    PubMed Central

    Lippold, Carsten; Danesh, Gholamreza; Schilgen, Markus; Drerup, Burkhard; Hackenberg, Lars

    2006-01-01

    Background The correlations between the sagittal jaw position and the cranio – cervical inclination are described in literature. Only few studies focus on the sagittal jaw position and the body posture using valid and objective orthopaedic examination methods. The aim of this study was to test the hypothesis that patients with malocclusions reveal significant differences in body posture compared to those without (upper thoracic inclination, kyphotic angle, lordotic angle and lower lumbar inclination). Methods Eighty-four healthy adult patients (with a mean age = 25.6 years and ranging from 16.1 to 55.8 years) were examined with informed consent. The orthodontic examination horizontal overjet (distance between upper and lower incisors) was determined by using an orthodontic digital sliding calliper. The subjects were subdivided in respect of the overjet with the following results: 18 revealed a normal overjet (Class I), 38 had an increased overjet (Class II) and 28 had an reversed overjet (Class III). Rasterstereography was used to carry out a three – dimensional back shape analysis. This method is based on photogrammetry. A three-dimensional shape was produced by analysing the distortion of parallel horizontal white light lines projected on the patient's back, followed by mathematical modelling. On the basis of the sagittal profile the upper thoracic inclination, the thoracic angle, the lordotic angle and the pelvic inclination were determined with a reported accuracy of 2.8° and the correlations to the sagittal jaw position were calculated by means of ANOVA, Scheffé and Kruskal-Wallis procedures. Results Between the different overjet groups, no statistically significant differences or correlations regarding the analysed back shape parameters could be obtained. However, comparing males and females there were statistically significant differences in view of the parameters 'lordotic angle' and 'pelvic inclination'. Conclusion No correlations between overjet and

  3. Postural proteinuria associated with left renal vein entrapment: a follow-up evaluation.

    PubMed

    Milani, Gregorio P; Mazzoni, Marta B M; Burdick, Larry; Bianchetti, Mario G; Fossali, Emilio F

    2010-06-01

    Imaging studies show entrapment of the left renal vein in the fork between the aorta and proximal superior mesenteric artery in most cases of isolated postural proteinuria. Therefore, it has been postulated that partial obstruction to the flow in the left renal vein in the upright position is a cause of this form of proteinuria. In a girl with isolated postural proteinuria, kidney ultrasonic imaging and Doppler flow scanning showed left renal vein entrapment. Seven years later, a new evaluation showed resolution of both postural proteinuria and left renal vein entrapment. The longitudinal observation provides substantial additional support for entrapment of the left renal vein by the aorta and superior mesenteric artery as a cause of isolated postural proteinuria.

  4. Evidence for Impaired Verbal Identification but Intact Nonverbal Recognition of Fearful Body Postures in Asperger's Syndrome

    ERIC Educational Resources Information Center

    Doody, John P.; Bull, Peter

    2013-01-01

    While most studies of emotion recognition in Asperger's Syndrome (AS) have focused solely on the verbal decoding of affective states, the current research employed the novel technique of using both nonverbal matching and verbal labeling tasks to examine the decoding of emotional body postures and facial expressions. AS participants performed…

  5. Impact of pregnancy on back pain and body posture in women

    PubMed Central

    Schröder, Guido; Kundt, Günther; Otte, Mandy; Wendig, Detlef; Schober, Hans-Christof

    2016-01-01

    [Purpose] The purpose of this single-center investigation was to study the impact of pregnancy on back pain and body posture. [Subjects] The subjects were 26 pregnant females. [Methods] Data were generated with a spine scanner (Diers® formetric 4D), trunk strength measurement (Diers® myoline), a numeric pain scale (0 to 10), and a biomechanical model. Parameters were compared during each trimester. [Results] The alteration in pain level at rest and lumbar lordosis angle in the females revealed a statistical trend during pregnancy. Spearman’s test showed positive correlations between body weight and trunk inclination during the second trimester, and between body weight and the kyphosis angle in the third trimester. The trunk inclination and the kyphosis angle revealed a negative correlation in the third trimester. Based on our analysis, the highest moments and muscle strength must be expended in the third trimester. The actual muscle strength is greatest in the second trimester. [Conclusion] Pain at rest must be given greater attention in pregnant females, and their increasing lumbar kyphosis must be counteracted. Exercising the deep segmental muscles may serve as a preventive measure. PMID:27190453

  6. A single muscle's multifunctional control potential of body dynamics for postural control and running

    PubMed Central

    Sponberg, Simon; Spence, Andrew J.; Mullens, Chris H.; Full, Robert J.

    2011-01-01

    A neuromechanical approach to control requires understanding how mechanics alters the potential of neural feedback to control body dynamics. Here, we rewrite activation of individual motor units of a behaving animal to mimic the effects of neural feedback without concomitant changes in other muscles. We target a putative control muscle in the cockroach, Blaberus discoidalis (L.), and simultaneously capture limb and body dynamics through high-speed videography and a micro-accelerometer backpack. We test four neuromechanical control hypotheses. We supported the hypothesis that mechanics linearly translates neural feedback into accelerations and rotations during static postural control. However, during running, the same neural feedback produced a nonlinear acceleration control potential restricted to the vertical plane. Using this, we reject the hypothesis from previous work that this muscle acts primarily to absorb energy from the body. The conversion of the control potential is paralleled by nonlinear changes in limb kinematics, supporting the hypothesis that significant mechanical feedback filters the graded neural feedback for running control. Finally, we insert the same neural feedback signal but at different phases in the dynamics. In this context, mechanical feedback enables turning by changing the timing and direction of the accelerations produced by the graded neural feedback. PMID:21502129

  7. Dysgnathia, orthognathic surgery and spinal posture.

    PubMed

    Sinko, K; Grohs, J-G; Millesi-Schobel, G; Watzinger, F; Turhani, D; Undt, G; Baumann, A

    2006-04-01

    The aim of this study was to evaluate the spine by video rasterstereography before and after orthognathic surgery. Twenty-nine patients (17 patients with a skeletal class III, 7 patients with a skeletal class II, and 5 patients with mandibular asymmetry) were evaluated preoperatively and 1 year postoperatively. Video rasterstereography is a method of back surface measurement and shape analysis using the moire topography. Orthognathic surgery in cases of class III and asymmetry did not lead to significant changes in body posture. In class II patients it led to some changes in body posture, but without orthopaedic consequences. It is concluded that orthognathic surgery causes minimal or no change in body posture.

  8. Biomechanical investigation of thoracolumbar spine in different postures during ejection using a combined finite element and multi-body approach.

    PubMed

    Du, Chengfei; Mo, Zhongjun; Tian, Shan; Wang, Lizhen; Fan, Jie; Liu, Songyang; Fan, Yubo

    2014-11-01

    The aim of this study is to investigate the dynamic response of a multi-segment model of the thoracolumbar spine and determine how the sitting posture affects the response under the impact of ejection. A nonlinear finite element model of the thoracolumbar-pelvis complex (T9-S1) was developed and validated. A multi-body dynamic model of a pilot was also constructed so an ejection seat restraint system could be incorporated into the finite element model. The distribution of trunk mass on each vertebra was also considered in the model. Dynamics analysis showed that ejection impact induced obvious axial compression and anterior flexion of the spine, which may contribute to spinal injuries. Compared with a normal posture, the relaxed posture led to an increase in stress on the cortical wall, endplate, and intradiscal pressure of 43%, 10%, 13%, respectively, and accordingly increased the risk of inducing spinal injuries.

  9. Biomechanical investigation of thoracolumbar spine in different postures during ejection using a combined finite element and multi-body approach.

    PubMed

    Du, Chengfei; Mo, Zhongjun; Tian, Shan; Wang, Lizhen; Fan, Jie; Liu, Songyang; Fan, Yubo

    2014-11-01

    The aim of this study is to investigate the dynamic response of a multi-segment model of the thoracolumbar spine and determine how the sitting posture affects the response under the impact of ejection. A nonlinear finite element model of the thoracolumbar-pelvis complex (T9-S1) was developed and validated. A multi-body dynamic model of a pilot was also constructed so an ejection seat restraint system could be incorporated into the finite element model. The distribution of trunk mass on each vertebra was also considered in the model. Dynamics analysis showed that ejection impact induced obvious axial compression and anterior flexion of the spine, which may contribute to spinal injuries. Compared with a normal posture, the relaxed posture led to an increase in stress on the cortical wall, endplate, and intradiscal pressure of 43%, 10%, 13%, respectively, and accordingly increased the risk of inducing spinal injuries. PMID:24827805

  10. Low back pain in drivers: The relative role of whole-body vibration, posture and manual materials handling

    NASA Astrophysics Data System (ADS)

    Okunribido, O. O.; Magnusson, M.; Pope, M. H.

    2006-12-01

    A cross-sectional study was conducted to investigate the relative role of whole-body vibration (WBV), posture and manual materials handling (MMH) as risk factors for low back pain (LBP). Using a validated questionnaire, information about health history, posture and MMH performed was obtained from 394 workers who drove vehicles as part of their job (according to seven predefined occupational groups) and 59 who did not. The intention was to reflect a wide range of exposures with the lower end of the exposure spectrum defined as that of non-manual workers who do not drive as part of their job. Based on the questionnaire responses and direct measurements of vibration exposure, personal aggregate measures of exposure were computed for each of the respondents, i.e., total vibration dose (TVD), posture score (PS) and manual handling score (MHS). Odds ratios (and 95% confidence intervals) for back pain were obtained from logistics regression models and log-linear backward elimination analysis was performed. The findings showed that 'combined exposure' due to posture and one or both of vibration and MMH, rather than the individual exposure to one of the three factors (WBV, posture, MMH) is the main contributor of the increased prevalence of LBP.

  11. Evaluation of the lambda model for human postural control during ankle strategy.

    PubMed

    Micheau, Philippe; Kron, Aymeric; Bourassa, Paul

    2003-09-01

    An accurate modeling of human stance might be helpful in assessing postural deficit. The objective of this article is to validate a mathematical postural control model for quiet standing posture. The postural dynamics is modeled in the sagittal plane as an inverted pendulum with torque applied at the ankle joint. The torque control system is represented by the physiological lambda model. Two neurophysiological command variables of the central nervous system, designated lambda and micro, establish the dynamic threshold muscle at which motoneuron recruitment begins. Kinematic data and electromyographic signals were collected on four young males in order to measure small voluntary sway and quiet standing posture. Validation of the mathematical model was achieved through comparison of the experimental and simulated results. The mathematical model allows computation of the unmeasurable neurophysiological commands lambda and micro that control the equilibrium position and stability. Furthermore, with the model it is possible to conclude that low-amplitude body sway during quiet stance is commanded by the central nervous system.

  12. Stochastic resonance whole-body vibration improves postural control in health care professionals: a worksite randomized controlled trial.

    PubMed

    Elfering, Achim; Schade, Volker; Stoecklin, Lukas; Baur, Simone; Burger, Christian; Radlinger, Lorenz

    2014-05-01

    Slip, trip, and fall injuries are frequent among health care workers. Stochastic resonance whole-body vibration training was tested to improve postural control. Participants included 124 employees of a Swiss university hospital. The randomized controlled trial included an experimental group given 8 weeks of training and a control group with no intervention. In both groups, postural control was assessed as mediolateral sway on a force plate before and after the 8-week trial. Mediolateral sway was significantly decreased by stochastic resonance whole-body vibration training in the experimental group but not in the control group that received no training (p < .05). Stochastic resonance whole-body vibration training is an option in the primary prevention of balance-related injury at work.

  13. Parkinson's Disease-Related Impairments in Body Movement, Coordination and Postural Control Mechanisms When Performing 80° Lateral Gaze Shifts.

    PubMed

    Bonnet, Cédrick T; Delval, Arnaud; Defebvre, Luc

    2015-09-01

    We investigated early signs of Parkinson's disease-related impairment in mediolateral postural control. Thirty-six participants (18 Hoehn & Yahr stage 2 patients in the off-drug condition and 18 healthy controls) were studied in a stationary gaze condition and when performing 80° lateral gaze shifts at 0.125 and 0.25 Hz. Body sway, coordination and postural control mechanisms were analyzed. All participants performed the visual tasks adequately. The patients were not unstable in the stationary gaze condition. In both groups, mediolateral ankle- and hip-based postural control mechanisms were significantly more active under gaze shift conditions than under the stationary gaze condition. As expected, the patients exhibited significantly greater angular movements of the lower back and significantly lower angular movements of the head (relative to controls) when performing gaze shifts. When considering linear displacements (rather than angular movements), the patients exhibited significantly greater displacements of the lower back and lower, slower displacements of the head than controls under gaze shift conditions. Relative to controls, the patients performed "en block" body movements. Overall, our results show that the patients' ankle- and hip-based mediolateral postural control mechanisms did not adapt to the difficulty of the visual task being performed.

  14. What is the most effective posture to conduct vibration from the lower to the upper extremities during whole-body vibration exercise?

    PubMed Central

    Tsukahara, Yuka; Iwamoto, Jun; Iwashita, Kosui; Shinjo, Takuma; Azuma, Koichiro; Matsumoto, Hideo

    2016-01-01

    Background Whole-body vibration (WBV) exercise is widely used for training and rehabilitation. However, the optimal posture for training both the upper and lower extremities simultaneously remains to be established. Objectives The objective of this study was to search for an effective posture to conduct vibration from the lower to the upper extremities while performing WBV exercises without any adverse effects. Methods Twelve healthy volunteers (age: 22–34 years) were enrolled in the study. To measure the magnitude of vibration, four accelerometers were attached to the upper arm, back, thigh, and calf of each subject. Vibrations were produced using a WBV platform (Galileo 900) with an amplitude of 4 mm at two frequencies, 15 and 30 Hz. The following three postures were examined: posture A, standing posture with the knees flexed at 30°; posture B, crouching position with no direct contact between the knees and elbows; and posture C, crouching position with direct contact between the knees and elbows. The ratio of the magnitude of vibration at the thigh, back, and upper arm relative to that at the calf was used as an index of vibration conduction. Results Posture B was associated with a greater magnitude of vibration to the calf than posture A at 15 Hz, and postures B and C were associated with greater magnitudes of vibration than posture A at 30 Hz. Posture C was associated with a vibration conduction to the upper arm that was 4.62 times and 8.26 times greater than that for posture A at 15 and 30 Hz, respectively. Conclusion This study revealed that a crouching position on a WBV platform with direct contact between the knees and elbows was effective for conducting vibration from the lower to the upper extremities. PMID:26793008

  15. Dynamic fe Model of Sitting Man Adjustable to Body Height, Body Mass and Posture Used for Calculating Internal Forces in the Lumbar Vertebral Disks

    NASA Astrophysics Data System (ADS)

    Pankoke, S.; Buck, B.; Woelfel, H. P.

    1998-08-01

    Long-term whole-body vibrations can cause degeneration of the lumbar spine. Therefore existing degeneration has to be assessed as well as industrial working places to prevent further damage. Hence, the mechanical stress in the lumbar spine—especially in the three lower vertebrae—has to be known. This stress can be expressed as internal forces. These internal forces cannot be evaluated experimentally, because force transducers cannot be implementated in the force lines because of ethical reasons. Thus it is necessary to calculate the internal forces with a dynamic mathematical model of sitting man.A two dimensional dynamic Finite Element model of sitting man is presented which allows calculation of these unknown internal forces. The model is based on an anatomic representation of the lower lumbar spine (L3-L5). This lumber spine model is incorporated into a dynamic model of the upper torso with neck, head and arms as well as a model of the body caudal to the lumbar spine with pelvis and legs. Additionally a simple dynamic representation of the viscera is used. All these parts are modelled as rigid bodies connected by linear stiffnesses. Energy dissipation is modelled by assigning modal damping ratio to the calculated undamped eigenvalues. Geometry and inertial properties of the model are determined according to human anatomy. Stiffnesses of the spine model are derived from static in-vitro experiments in references [1] and [2]. Remaining stiffness parameters and parameters for energy dissipation are determined by using parameter identification to fit measurements in reference [3]. The model, which is available in 3 different postures, allows one to adjust its parameters for body height and body mass to the values of the person for which internal forces have to be calculated.

  16. Dog experts' brains distinguish socially relevant body postures similarly in dogs and humans.

    PubMed

    Kujala, Miiamaaria V; Kujala, Jan; Carlson, Synnöve; Hari, Riitta

    2012-01-01

    We read conspecifics' social cues effortlessly, but little is known about our abilities to understand social gestures of other species. To investigate the neural underpinnings of such skills, we used functional magnetic resonance imaging to study the brain activity of experts and non-experts of dog behavior while they observed humans or dogs either interacting with, or facing away from a conspecific. The posterior superior temporal sulcus (pSTS) of both subject groups dissociated humans facing toward each other from humans facing away, and in dog experts, a distinction also occurred for dogs facing toward vs. away in a bilateral area extending from the pSTS to the inferior temporo-occipital cortex: the dissociation of dog behavior was significantly stronger in expert than control group. Furthermore, the control group had stronger pSTS responses to humans than dogs facing toward a conspecific, whereas in dog experts, the responses were of similar magnitude. These findings suggest that dog experts' brains distinguish socially relevant body postures similarly in dogs and humans.

  17. Additive effect of repeated bouts of individualized frequency whole body vibration on postural stability in young adults.

    PubMed

    Dickin, D Clark; Heath, Jacqueline E

    2014-08-01

    Whole body vibration (WBV) has been shown to improve force and power output as well as flexibility and speed, with improvements suggested to result from reduced electromechanical delays, improved rate of force development, and sensitivity of muscle spindles. Fixed frequency studies on postural control have been somewhat equivocal; however, individualized frequency protocols have shown promising results in other motor tasks. To assess this, 18 healthy young adults experienced three 4-minute WBV sessions with postural control assessed before vibration, after multiple exposures, and during recovery, with altered levels of sensory information available to the participants. Sway velocity, sway path length, and sway area were assessed in each environment. Study findings revealed that stability was impacted following WBV, with more challenging environments eliciting improvements persisting for 20 minutes. When the environment was less challenging, postural stability was impaired; however, the effects dissipated quickly (10-20 min). It was determined that exposure to individualized frequency WBV served to impair postural control when the challenge was low, but resulted in heightened stability when the overall challenge was high and vestibular information was needed for stability.

  18. Changes in apparent body orientation and sensory localization induced by vibration of postural muscles - Vibratory myesthetic illusions

    NASA Technical Reports Server (NTRS)

    Lackner, J. R.; Levine, M. S.

    1979-01-01

    Human experiments are carried out which support the observation of Goodwin (1973) and Goodwin et al. (1972) that vibration of skeletal muscles can elicit illusory limb motion. These experiments extend the class of possible myesthetic illusions by showing that vibration of the appropriate muscles can produce illusory body motion in nearly any desired direction. Such illusory changes in posture occur only when visual information about body orientation is absent; these changes in apparent posture are sometimes accompanied by a slow-phase nystagmus that compensates for the direction of apparent body motion. During illusory body motion a stationary target light that is fixated will appear to move with the body at the same apparent velocity. However, this pattern of apparent body motion and conjoint visual - defined as propriogyral illusion - is suppressed if the subject is in a fully illuminated environment providing cues about true body orientation. Persuasive evidence is thus provided for the contribution of both muscle afferent and touch-pressure information to the supraspinal mechanisms that determine apparent orientation on the basis of ongoing patterns of interoceptive and exteroceptive activity.

  19. Prediction of postural risk of fall initiation based on a two-variable description of body dynamics: position and velocity of center of mass.

    PubMed

    Honarvar, Mohammad Hadi; Nakashima, Motomu

    2013-10-01

    This research addresses the question: what is the risk of fall initiation at a certain human posture? There are postures from which no one is able to keep their balance and a fall will surely initiate (risk=1), and others from which everyone may regain their stability (risk=0). In other postures, only a portion of people can control their stability. One may interpret risk to chance of a fall to be initiated, and based on the portion of fallers assign a risk value to a given human posture (postural risk). Human posture can be mapped to a point in a 2-dimensional space: the x-v plane, the axes of which are horizontal components of the position and velocity of the center of mass of the body. For every pair of (x, v), the outcome of the balance recovery problem defines whether a person with a given strength level is able to regain their stability when released from a posture corresponding to that point. Using strength distribution data, we estimated the portion of the population who will initiate a fall if starting at a certain posture. A fast calculation approach is also introduced to replace the time-consuming method of solving the recovery problem many times. Postural risk of fall initiation for situations expressed by (x, v) pairs for the entire x-v plane is calculated and shown in a color-map.

  20. Kinect-Based Virtual Game for the Elderly that Detects Incorrect Body Postures in Real Time.

    PubMed

    Saenz-de-Urturi, Zelai; Garcia-Zapirain Soto, Begonya

    2016-01-01

    Poor posture can result in loss of physical function, which is necessary to preserving independence in later life. Its decline is often the determining factor for loss of independence in the elderly. To avoid this, a system to correct poor posture in the elderly, designed for Kinect-based indoor applications, is proposed in this paper. Due to the importance of maintaining a healthy life style in senior citizens, the system has been integrated into a game which focuses on their physical stimulation. The game encourages users to perform physical activities while the posture correction system helps them to adopt proper posture. The system captures limb node data received from the Kinect sensor in order to detect posture variations in real time. The DTW algorithm compares the original posture with the current one to detect any deviation from the original correct position. The system was tested and achieved a successful detection percentage of 95.20%. Experimental tests performed in a nursing home with different users show the effectiveness of the proposed solution. PMID:27196903

  1. Kinect-Based Virtual Game for the Elderly that Detects Incorrect Body Postures in Real Time

    PubMed Central

    Saenz-de-Urturi, Zelai; Garcia-Zapirain Soto, Begonya

    2016-01-01

    Poor posture can result in loss of physical function, which is necessary to preserving independence in later life. Its decline is often the determining factor for loss of independence in the elderly. To avoid this, a system to correct poor posture in the elderly, designed for Kinect-based indoor applications, is proposed in this paper. Due to the importance of maintaining a healthy life style in senior citizens, the system has been integrated into a game which focuses on their physical stimulation. The game encourages users to perform physical activities while the posture correction system helps them to adopt proper posture. The system captures limb node data received from the Kinect sensor in order to detect posture variations in real time. The DTW algorithm compares the original posture with the current one to detect any deviation from the original correct position. The system was tested and achieved a successful detection percentage of 95.20%. Experimental tests performed in a nursing home with different users show the effectiveness of the proposed solution. PMID:27196903

  2. Development of a computational framework to adjust the pre-impact spine posture of a whole-body model based on cadaver tests data.

    PubMed

    Poulard, David; Subit, Damien; Donlon, John-Paul; Kent, Richard W

    2015-02-26

    A method was developed to adjust the posture of a human numerical model to match the pre-impact posture of a human subject. The method involves pulling cables to prescribe the position and orientation of the head, spine and pelvis during a simulation. Six postured models matching the pre-impact posture measured on subjects tested in previous studies were created from a human numerical model. Posture scalars were measured on pre- and after applying the method to evaluate its efficiency. The lateral leaning angle θL defined between T1 and the pelvis in the coronal plane was found to be significantly improved after application with an average difference of 0.1±0.1° with the PMHS (4.6±2.7° before application). This method will be applied in further studies to analyze independently the contribution of pre-impact posture on impact response using human numerical models.

  3. Development of a computational framework to adjust the pre-impact spine posture of a whole-body model based on cadaver tests data.

    PubMed

    Poulard, David; Subit, Damien; Donlon, John-Paul; Kent, Richard W

    2015-02-26

    A method was developed to adjust the posture of a human numerical model to match the pre-impact posture of a human subject. The method involves pulling cables to prescribe the position and orientation of the head, spine and pelvis during a simulation. Six postured models matching the pre-impact posture measured on subjects tested in previous studies were created from a human numerical model. Posture scalars were measured on pre- and after applying the method to evaluate its efficiency. The lateral leaning angle θL defined between T1 and the pelvis in the coronal plane was found to be significantly improved after application with an average difference of 0.1±0.1° with the PMHS (4.6±2.7° before application). This method will be applied in further studies to analyze independently the contribution of pre-impact posture on impact response using human numerical models. PMID:25596635

  4. Postural Control in Dual-Task Situations: Does Whole-Body Fatigue Matter?

    PubMed Central

    Beurskens, Rainer; Haeger, Matthias; Kliegl, Reinhold; Roecker, Kai; Granacher, Urs

    2016-01-01

    Postural control is important to cope with demands of everyday life. It has been shown that both attentional demand (i.e., cognitive processing) and fatigue affect postural control in young adults. However, their combined effect is still unresolved. Therefore, we investigated the effects of fatigue on single- (ST) and dual-task (DT) postural control. Twenty young subjects (age: 23.7 ± 2.7) performed an all-out incremental treadmill protocol. After each completed stage, one-legged-stance performance on a force platform under ST (i.e., one-legged-stance only) and DT conditions (i.e., one-legged-stance while subtracting serial 3s) was registered. On a second test day, subjects conducted the same balance tasks for the control condition (i.e., non-fatigued). Results showed that heart rate, lactate, and ventilation increased following fatigue (all p < 0.001; d = 4.2–21). Postural sway and sway velocity increased during DT compared to ST (all p < 0.001; d = 1.9–2.0) and fatigued compared to non-fatigued condition (all p < 0.001; d = 3.3–4.2). In addition, postural control deteriorated with each completed stage during the treadmill protocol (all p < 0.01; d = 1.9–3.3). The addition of an attention-demanding interference task did not further impede one-legged-stance performance. Although both additional attentional demand and physical fatigue affected postural control in healthy young adults, there was no evidence for an overadditive effect (i.e., fatigue-related performance decrements in postural control were similar under ST and DT conditions). Thus, attentional resources were sufficient to cope with the DT situations in the fatigue condition of this experiment. PMID:26796320

  5. Photogrammetry as a tool for the postural evaluation of the spine: A systematic review

    PubMed Central

    Furlanetto, Tássia Silveira; Sedrez, Juliana Adami; Candotti, Cláudia Tarragô; Loss, Jefferson Fagundes

    2016-01-01

    AIM: To evaluate the use of photogrammetry and identify the mathematical procedures applied when evaluating spinal posture. METHODS: A systematic search using keywords was conducted in the PubMed, EMBASE, Scopus, Science and Medicine® databases. The following inclusion criteria adopted were: (1) the use of photogrammetry as a method to evaluate spinal posture; (2) evaluations of spinal curvature in the sagittal and/or frontal plane; (3) studies published within the last three decades; and (4) written entirely in English. The exclusion criteria were: (1) studies which objective involved the verification of some aspect of validation of instruments; (2) studies published as abstracts and those published in scientific events; and (3) studies using evaluation of the anteriorization of the head to determine the angular positioning of the cervical spine. The articles in this review were included and evaluated for their methodological quality, based on the Downs and Black scale, by two independent reviewers. RESULTS: Initially, 1758 articles were found, 76 of which were included upon reading the full texts and 29 were included in accordance with the predetermined criteria. In addition, after analyzing the references in those articles, a further six articles were selected, so that 35 articles were included in this review. This systematic review revealed that the photogrammetry has been using in observational studies. Furthermore, it was also found that, although the data collection methodologies are similar across the studies, in relation to aspects of data analysis, the methodologies are very different, especially regarding the mathematical routines employed to support different postural evaluation software. CONCLUSION: With photogrammetry, the aim of the assessment, whether it is for clinical, research or collective health purposes, must be considered when choosing which protocol to use to evaluate spinal posture. PMID:26925386

  6. Postural sway with earth-fixed and body-referenced finger contact in young and older adults.

    PubMed

    Reginella, R L; Redfern, M S; Furman, J M

    1999-01-01

    Sensory information from lightly touching a reference with the hand is known to influence postural sway in young adults. The primary aim of this study was to compare the influence of finger contact (FC) with an earth-fixed reference to the influence of FC with a body-fixed reference. A second goal of this study was to determine if FC is used differently by older adults compared to younger adults. Using a force plate, center of pressure at the feet was recorded from blindfolded young and older subjects during several conditions. Subjects either did or did not lightly touch a force-sensitive plate that was either earth-fixed or moved forward and backward in synchrony with body sway (that is, sway-referenced). In addition, support surface conditions were also varied, including a fixed floor and a sway-referenced floor using an Equitest. Results showed that the type of FC, floor condition, and age each had an effect on postural sway. Touching an earth-fixed plate decreased postural sway as compared to no touching, while touching a sway-referenced plate increased sway. This influence of FC was enhanced when the floor was sway-referenced. Although older subjects swayed more than young subjects overall, no age-FC interactions occurred, indicating that FC was not utilized differently between the age groups. This study suggests that FC cannot be disregarded as erroneous, especially when proprioceptive information from the legs is distorted. Further, FC is integrated with other sensory information by the postural control system similarly in young and older persons. PMID:10378181

  7. Effects of body mass index on foot posture alignment and core stability in a healthy adult population

    PubMed Central

    AlAbdulwahab, Sami S.; Kachanathu, Shaji John

    2016-01-01

    Foot biomechanics and core stability (CS) play significant roles in the quality of standing and walking. Minor alterations in body composition may influence base support or CS strategies. The aim of this study was to investigate the effect of the body mass index (BMI) on the foot posture index (FPI) and CS in a healthy adult population. A total of 39 healthy adult subjects with a mean age of 24.3±6.4 years and over-weight BMI values between 25 and 29.9 kg/m2 (27.43±6.1 kg/m2) participated in this study. Foot biomechanics were analyzed using the FPI. CS was assessed using a plank test with a time-to-failure trial. The Spearman correlation coefficient indicated a significant correlation between BMI and both the FPI (r=0.504, P=0.001) and CS (r= −0.34, P=0.036). Present study concluded that an overweight BMI influences foot posture alignment and body stability. Consequently, BMI should be considered during rehabilitation management for lower extremity injuries and body balance. PMID:27419113

  8. Effects of body mass index on foot posture alignment and core stability in a healthy adult population.

    PubMed

    AlAbdulwahab, Sami S; Kachanathu, Shaji John

    2016-06-01

    Foot biomechanics and core stability (CS) play significant roles in the quality of standing and walking. Minor alterations in body composition may influence base support or CS strategies. The aim of this study was to investigate the effect of the body mass index (BMI) on the foot posture index (FPI) and CS in a healthy adult population. A total of 39 healthy adult subjects with a mean age of 24.3±6.4 years and over-weight BMI values between 25 and 29.9 kg/m2 (27.43±6.1 kg/m2) participated in this study. Foot biomechanics were analyzed using the FPI. CS was assessed using a plank test with a time-to-failure trial. The Spearman correlation coefficient indicated a significant correlation between BMI and both the FPI (r=0.504, P=0.001) and CS (r= -0.34, P=0.036). Present study concluded that an overweight BMI influences foot posture alignment and body stability. Consequently, BMI should be considered during rehabilitation management for lower extremity injuries and body balance.

  9. Angry posture.

    PubMed

    Rosário, Jose Luis; Diógenes, Maria Suely Bezerra; Mattei, Rita; Leite, José Roberto

    2016-07-01

    Postural abnormalities can affect the emotions and vice-versa. The aim of the present study was to investigate the existence of a relationship between subjective anger and body posture in 28 women, aged between 20 and 39 years, with a normal body mass index (or underweight) and an absence of neurological, psychiatric or musculoskeletal disorders. The postural parameters photographed were the inclination of the shoulders, protrusion of the head, hyperextension of the knees and shoulder elevation. The degree of anger was rated by analogue scales representing current and usual anger. The results indicated that a relationship exists between current anger and the inclination of the shoulders (p = 0.03), protrusion of the head (p = 0.05) and hyperextension of the knees (p = 0.05). Correlations were found between usual anger, shoulder elevation (p = 0.05) and hyperextension of the knees (p = 0.05). In conclusion, posture is associated with emotions, and usual anger can lead to shoulder protraction. PMID:27634065

  10. The effects of body posture and temperament on heart rate variability in dairy cows.

    PubMed

    Frondelius, Lilli; Järvenranta, Kirsi; Koponen, Taija; Mononen, Jaakko

    2015-02-01

    Reactivity of cattle affects many aspects of animal production (e.g. reduced milk and meat production). Animals have individual differences in temperament and emotional reactivity, and these differences can affect how animals react to stressful and fear-eliciting events. Heart rate variability (HRV) is a good indicator of stress and balance of the autonomous nervous system, and low parasympathetic activity is connected with higher emotional reactivity. The study had two specific aims: (1) to compare HRV in dairy cows for standing and lying postures (no earlier results available), and (2) to assess whether dairy cows' emotional reactivity is connected to their HRV values. Eighteen dairy cows were subjected twice to a handling test (HT): morning (HT1) and afternoon (HT2), to evaluate emotional reactivity (avoidance score, AS). HRV was measured during HT (standing). HRV baseline values, both standing and lying down, were measured one week before HTs. HRV was analyzed with time and frequency domain analyses and with the Recurrence Quantification Analysis (RQA). Heart rate (HR), low-frequency/high-frequency band ratio (LH/HF), % determinism (%DET) and longest diagonal line segment in the recurrence plot (Lmax) were higher (p<0.05) while the cows were standing than when lying down, whereas the root mean square of successive R-R intervals (RMSSD) (p<0.05) and power of the high-frequency band (HF) (p<0.1) were higher while the animals were lying down. HR, the standard deviation of all interbeat intervals (SDNN), RMSSD, HF, power of the low-frequency band (LF), % recurrence (%REC), %DET, Shannon entropy (p<0.05), and HF (p<0.1) were higher during the handling test compared to standing baseline values. AS (i.e. tendency to avoid handling) correlated positively with SDNN (r=0.48, p<0.05), RMSSD (r=0.54, p<0.05), HF, RMSSD (r=0.46, p<0.1) and LF (r=0.57, p<0.05), and negatively with %DET (r=-0.53, p<0.05), entropy (r=-0.60, p<0.05) and Lmax (r=-0.55, p<0.05) in the baseline

  11. Postural Control and Automaticity in Dyslexic Children: The Relationship between Visual Information and Body Sway

    ERIC Educational Resources Information Center

    Barela, Jose A.; Dias, Josenaldo L.; Godoi, Daniela; Viana, Andre R.; de Freitas, Paulo B.

    2011-01-01

    Difficulty with literacy acquisition is only one of the symptoms of developmental dyslexia. Dyslexic children also show poor motor coordination and postural control. Those problems could be associated with automaticity, i.e., difficulty in performing a task without dispending a fair amount of conscious efforts. If this is the case, dyslexic…

  12. Does whole-body vibration training have acute residual effects on postural control ability of elderly women?

    PubMed

    Carlucci, Flaminia; Mazzà, Claudia; Cappozzo, Aurelio

    2010-12-01

    The purpose of this study was to investigate acute residual effects of a single vibration session on balance control in a group of elderly women. Several studies, in fact, have shown that whole-body vibration (WBV) training may improve balance in the elderly, but possible side effects of acute exposure to WBV, such as temporary reduction of balance control ability because of perturbations of the vestibular system, have not been investigated. Twenty-two healthy elderly women (71.8 ± 4.7 years of age) were trained with a 9.5-minute bout of static and dynamic knee-extensor exercises executed on a vibrating platform (Well-net Vibe Revolution). The vibration frequency was set at 35 Hz. A subgroup of 14 subjects performed the same exercise protocol also without the vibrations to discriminate between vibration and exercise effects. Balance control ability was assessed through computerized posturography: a force plate (Bertec Co, Columbus, OH, USA) was used to measure the center of pressure trajectories during 4 different experimental trials: before, immediately after, 15 minutes after, and 60 minutes after the training. A set of postural parameters, typically adopted to assess elderly subjects, was then computed and 2-way analysis of variance was used to determine differences between values found in the 4 postural tests (level of significance p = 0.05) in the 2 groups. The results showed no significant variations in the postural parameters recorded during the 4 sessions. A significant group effect was found for 2 postural parameters, with no interaction between the 2 factors. In conclusion, the proposed single bout of WBV does not induce dangerous acute effects on elderly women balance control ability and could be safely administered as part of a long-term intervention program. PMID:21088549

  13. A comparison of three observational techniques for assessing postural loads in industry.

    PubMed

    Kee, Dohyung; Karwowski, Waldemar

    2007-01-01

    This study aims to compare 3 observational techniques for assessing postural load, namely, OWAS, RULA, and REBA. The comparison was based on the evaluation results generated by the classification techniques using 301 working postures. All postures were sampled from the iron and steel, electronics, automotive, and chemical industries, and a general hospital. While only about 21% of the 301 postures were classified at the action category/level 3 or 4 by both OWAS and REBA, about 56% of the postures were classified into action level 3 or 4 by RULA. The inter-method reliability for postural load category between OWAS and RULA was just 29.2%, and the reliability between RULA and REBA was 48.2%. These results showed that compared to RULA, OWAS, and REBA generally underestimated postural loads for the analyzed postures, irrespective of industry, work type, and whether or not the body postures were in a balanced state.

  14. The influence of body posture, arm movement, and work stress on trapezius activity during computer work.

    PubMed

    Mork, Paul Jarle; Westgaard, Rolf H

    2007-11-01

    The study aimed to determine the influence of arm posture and movement on trapezius activity of computer workers, considering the full workday. A second aim was to investigate if work periods perceived as stressful were associated with elevated or more sustained muscle activity pattern. Twenty-six computer workers performing call-center (n=11), help desk (n=7), or secretarial (n=8) work tasks participated. Bilateral trapezius surface electromyographic (sEMG) activity and heart rate was recorded throughout the workday. Simultaneous inclinometer recordings from left thigh and upper arms identified periods with sitting, standing, and walking, as well as arm posture and movement. Perceived work stress and tension were recorded on visual analog scales (VAS) every hour. Trapezius sEMG activity was low in seated posture [group median 1.8 and 0.9% of activity at maximal voluntary contraction (%EMGmax) for dominant and non-dominant side] and was elevated in standing (3.0 and 2.5% EMGmax) and walking (3.9 and 3.4% EMGmax). In seated posture (mean duration 79% of workday) arm movement consistently influenced trapezius activity, accounting for approximately 20% of intra-individual variation in trapezius activity. Arm elevation was on average not associated with trapezius activity when seated; however, considerable individual variation was observed. There was no indication of increase in trapezius activity or more sustained activity pattern, nor in heart rate, in high-stress versus low-stress periods, comparing periods with seated posture for the subjects reporting contrasts of at least two VAS units in stress (n=16) or tension (n=14) score. PMID:17653757

  15. Effects of whole-body vibration training on explosive strength and postural control in young female athletes.

    PubMed

    Fort, Azahara; Romero, Daniel; Bagur, Caritat; Guerra, Myriam

    2012-04-01

    This study aimed to evaluate the effectiveness of a whole-body vibration training program to improve neuromuscular performance in young elite female athletes. Twenty-three women basketball players (14-18 years old) were randomly assigned to a control group (CG, n = 11) or to a whole-body vibration group (WBVG, n = 12). During the study period, both groups continued their usual training program, but the WBVG also underwent a 15-week vibration training program. We analyzed the countermovement jump test (CMJ), the 1-leg hop test for the right leg and for the left leg, and the single-limb standing balance for both legs and with eyes open and closed at 3 time points: before training (T1), after an 8-week training period (T2), and after a further 7-week training period (T3). Compared with the CG, CMJ increased significantly in the WBVG from T1 to T2 (6.47%, p < 0.001), T1 to T3 (10.07%, p = 0.005), and T2 to T3 (3.38%, p < 0.001). One-leg hop test for the right and left legs also showed significantly higher values in WBVG from T1 to T2 (10.12%, p < 0.001 and 9.63%, p = 0.002, respectively) and T1 to T3 (14.17%, p = 0.001 and 15.17%, p = 0.004, respectively). Lateral deviation of the center of pressure in the closed eyes test decreased significantly in WBVG for both right and left leg, from T1 to T2 (-22.20%, p = 0.043 and -34.77%, p < 0.001, respectively) and from T1 to T3 (-33.14%, p = 0.027 and -33.58%, p = 0.043, respectively) compared with the CG. In conclusion, our results show that a 15-week whole-body vibration training program improves explosive strength and postural stability in adolescent female basketball players.

  16. Age-related changes in distribution of body weight on soles of feet for selected actions and postures.

    PubMed

    Yanagida, T; Asami, T

    1997-12-01

    We investigated age-related changes in the distribution of body weight on soles of feet in 878 healthy subjects ranging from 5 to 80 years of age. By modifying Morton's Staticometer, we constructed an instrument for measuring body-weight distribution over three areas of soles of the feet, the big toe (inner forefoot), the other four toes combined (outer forefoot) and the heels for both feet, thus a total of six areas. The weights in the six areas were recorded at the completion of nine selected actions and postures. We observed that for inhaling and exhaling standing postures, generally younger subjects had a ratio close to 1:2:3 for weights recorded for the inner toe:outer toes:heels as observed by Morton, but elderly subjects had a smaller value than 3 for the heel. The body-weight distribution tended to shift from heels to outer toes across age groups, which was more distinctly observed in women than in men.

  17. Fluid Shifts: Otoacoustical Emission Changes in Response to Posture and Lower Body Negative Pressure

    NASA Technical Reports Server (NTRS)

    Melgoza, R.; Kemp, D.; Ebert, D.; Danielson, R.; Stenger, M.; Hargens, A.; Dulchavsky, S.

    2016-01-01

    INTRODUCTION: The purpose of the NASA Fluid Shifts Study is to characterize fluid distribution and compartmentalization associated with long-duration spaceflight and to correlate these findings with vision changes and other elements of the visual impairment and intracranial pressure (VIIP) syndrome. VIIP signs and symptoms, as well as postflight lumbar puncture data, suggest that elevated intracranial pressure (ICP) may be associated with spaceflight-induced cephalad fluid shifts, but this hypothesis has not been tested. Due to the invasive nature of direct measures of ICP, a noninvasive technique of monitoring ICP is desired for use during spaceflight. The phase angle and amplitude of otoacoustic emissions (OAEs) have been shown to be sensitive to posture change and ICP (1, 2), therefore use of OAEs is an attractive option. OAEs are low-level sounds produced by the sensory cells of the cochlea in response to auditory stimulation. These sounds travel peripherally from the cochlea, through the oval window, to the ear canal where they can be recorded. OAE transmission is sensitive to changes in the stiffness of the oval window, occurring as a result of changes in cochlear pressure. Increased stiffness of the oval window largely affects the transmission of sound from the cochlea at frequencies between 800 Hz and 1600 Hz. OAEs can be self-recorded in the laboratory or on the ISS using a handheld device. Our primary objectives regarding OAE measures in this experiment were to 1) validate this method during preflight testing of each crewmember (while sitting, supine and in head-down tilt position), and 2) determine if OAE measures (and presumably ICP) are responsive to lower body negative pressure and to spaceflight. METHODS: Distortion-product otoacoustic emissions (DPOAEs) and transient evoked otoacoustic emissions (TEOAEs) were recorded preflight using the Otoport Advance OAE system (Otodynamics Ltd., Hatfield, UK). Data were collected in four conditions (seated

  18. Myoelectric Response of Back Muscles to Vertical Random Whole-Body Vibration with Different Magnitudes at Different Postures

    NASA Astrophysics Data System (ADS)

    BLÜTHNER, R.; SEIDEL, H.; HINZ, B.

    2002-05-01

    Back muscle forces contribute essentially to the whole-body vibration-induced spinal load. The electromyogram (EMG) can help to estimate these forces during whole-body vibration (WBV). Thirty-eight subjects were exposed to identical random low-frequency WBV (0·7, 1·0 and 1·4 m/s-2 r.m.s. weighted acceleration) at a relaxed, erect and bent forward postures. The acceleration of the seat and the force between the seat and the buttocks were measured. Six EMGs were derived from the right side of the m. trapezius pars descendens, m. ileocostalis lumborum pars thoracis, m. ileocostalis lumborum pars lumborum; m. longissimus thoracis pars thoracis, m. longissimus thoracis pars lumborum, and lumbar multifidus muscle. All data were filtered for anti-aliasing and sampled with 1000 Hz. Artefacts caused by the ECG in the EMG were identified and eliminated in the time domain using wavelets. The individually rectified and normalized EMGs were averaged across subjects. The EMGs without WBV exhibited characteristic patterns for the three postures examined. The coherence and transfer functions indicated characteristic myoelectric responses to random WBV with several effects of posture and WBV magnitude. A comprehensive set of transfer functions from the seat acceleration or the mean normalized input force to the mean processed EMG was presented.The results can be used for the development of more sophisticated models with a separate control of various back muscle groups. However, the EMG-force relationship under dynamic conditions needs to be examined in more detail before the results can be implemented. Since different reflex mechanisms depending on the frequency of WBV are linked with different types of active muscle fibres, various time delays between the EMG and muscle force may be necessary.

  19. Evidence for subjective values guiding posture and movement coordination in a free-endpoint whole-body reaching task.

    PubMed

    Hilt, P M; Berret, B; Papaxanthis, C; Stapley, P J; Pozzo, T

    2016-01-01

    When moving, humans must overcome intrinsic (body centered) and extrinsic (target-related) redundancy, requiring decisions when selecting one motor solution among several potential ones. During classical reaching studies the position of a salient target determines where the participant should reach, constraining the associated motor decisions. We aimed at investigating implicit variables guiding action selection when faced with the complexity of human-environment interaction. Subjects had to perform whole body reaching movements towards a uniform surface. We observed little variation in the self-chosen motor strategy across repeated trials while movements were variable across subjects being on a continuum from a pure 'knee flexion' associated with a downward center of mass (CoM) displacement to an 'ankle dorsi-flexion' associated with an upward CoM displacement. Two optimality criteria replicated these two strategies: a mix between mechanical energy expenditure and joint smoothness and a minimization of the amount of torques. Our results illustrate the presence of idiosyncratic values guiding posture and movement coordination that can be combined in a flexible manner as a function of context and subject. A first value accounts for the reach efficiency of the movement at the price of selecting possibly unstable postures. The other predicts stable dynamic equilibrium but requires larger energy expenditure and jerk. PMID:27053508

  20. Evidence for subjective values guiding posture and movement coordination in a free-endpoint whole-body reaching task

    PubMed Central

    Hilt, P. M.; Berret, B.; Papaxanthis, C.; Stapley, P. J.; Pozzo, T.

    2016-01-01

    When moving, humans must overcome intrinsic (body centered) and extrinsic (target-related) redundancy, requiring decisions when selecting one motor solution among several potential ones. During classical reaching studies the position of a salient target determines where the participant should reach, constraining the associated motor decisions. We aimed at investigating implicit variables guiding action selection when faced with the complexity of human-environment interaction. Subjects had to perform whole body reaching movements towards a uniform surface. We observed little variation in the self-chosen motor strategy across repeated trials while movements were variable across subjects being on a continuum from a pure ‘knee flexion’ associated with a downward center of mass (CoM) displacement to an ‘ankle dorsi-flexion’ associated with an upward CoM displacement. Two optimality criteria replicated these two strategies: a mix between mechanical energy expenditure and joint smoothness and a minimization of the amount of torques. Our results illustrate the presence of idiosyncratic values guiding posture and movement coordination that can be combined in a flexible manner as a function of context and subject. A first value accounts for the reach efficiency of the movement at the price of selecting possibly unstable postures. The other predicts stable dynamic equilibrium but requires larger energy expenditure and jerk. PMID:27053508

  1. LBP and lower limb discrepancy: 3D evaluation of postural rebalancing via underfoot wedge correction.

    PubMed

    D'Amico, Moreno; Roncoletta, Piero; Di Felice, Francesca; Porto, Daniele; Bellomo, Rosagrazia; Saggini, Raoul

    2012-01-01

    Leg Length Discrepancy (LLD) is very often associated to Low Back Pain (LBP), but still controversial is the use of underfoot wedge correction (heel rise) to re-balance pelvis and trunk posture. In a review of our last 5 years clinical activity we observed that more than 70% out of 300 LBP patients presented a LLD. In more than 80 % we ascertained, via Baropodography, the presence of underfoot asymmetric load, during standing. More durable therapy recovery effect has been observed when LLD correction had been adopted. These reasons led us to start a study to assess if a Full 3D multifactorial Posture evaluation approach, by means of Opto-electronic device associated to foot pressure maps recording, was able to quantitatively discriminate the clinically observed phenomena. On a 94 LBP (av. age 46.3±16 Y range 15-82 Y) patients sample, 83 (88%) have been found to improve posture when LLD was corrected. The 94 patients showed a mean lower limb discrepancy of μ=8±3.2mm associated to a mean scoliotic lumbar curve μ=10.5°±5.1° Cobb (frontal plane), mean Spinal offset μ=6.6±4.9mm and mean Global offset 10.7±8.8mm. The applied paired t-test comparison (indifferent vs. corrected orthostasis) showed significant (p < 0.05) postural improvements could be obtained in the whole or in a part of the considered parameters, both in rebalancing and in spine deformities reduction after the application of suitable under-foot wedge. The joint 3D opto-electronic and foot pressure map approach proved to be effective to control several clinical parameters with statistical significance.

  2. Effect of an Ergonomics-Based Educational Intervention Based on Transtheoretical Model in Adopting Correct Body Posture Among Operating Room Nurses

    PubMed Central

    Moazzami, Zeinab; Dehdari, Tahere; Taghdisi, Mohammad Hosein; Soltanian, Alireza

    2016-01-01

    Background: One of the preventive strategies for chronic low back pain among operating room nurses is instructing proper body mechanics and postural behavior, for which the use of the Transtheoretical Model (TTM) has been recommended. Methods: Eighty two nurses who were in the contemplation and preparation stages for adopting correct body posture were randomly selected (control group = 40, intervention group = 42). TTM variables and body posture were measured at baseline and again after 1 and 6 months after the intervention. A four-week ergonomics educational intervention based on TTM variables was designed and conducted for the nurses in the intervention group. Results: Following the intervention, a higher proportion of nurses in the intervention group moved into the action stage (p < 0.05). Mean scores of self-efficacy, pros, experimental processes and correct body posture were also significantly higher in the intervention group (p < 0.05). No significant differences were found in the cons and behavioral processes, except for self-liberation, between the two groups (p > 0.05) after the intervention. Conclusions: The TTM provides a suitable framework for developing stage-based ergonomics interventions for postural behavior. PMID:26925897

  3. Can Quiet Standing Posture Predict Compensatory Postural Adjustment?

    PubMed Central

    Moya, Gabriel Bueno Lahóz; Siqueira, Cássio Marinho; Caffaro, Renê Rogieri; Fu, Carolina; Tanaka, Clarice

    2009-01-01

    OBJECTIVE The aim of this study was to analyze whether quiet standing posture is related to compensatory postural adjustment. INTRODUCTION The latest data in clinical practice suggests that static posture may play a significant role in musculoskeletal function, even in dynamic activities. However, no evidence exists regarding whether static posture during quiet standing is related to postural adjustment. METHODS Twenty healthy participants standing on a movable surface underwent unexpected, standardized backward and forward postural perturbations while kinematic data were acquired; ankle, knee, pelvis and trunk positions were then calculated. An initial and a final video frame representing quiet standing posture and the end of the postural perturbation were selected in such a way that postural adjustments had occurred between these frames. The positions of the body segments were calculated in these initial and final frames, together with the displacement of body segments during postural adjustments between the initial and final frames. The relationship between the positions of body segments in the initial and final frames and their displacements over this time period was analyzed using multiple regressions with a significance level of p ≤ 0.05. RESULTS We failed to identify a relationship between the position of the body segments in the initial and final frames and the associated displacement of the body segments. DISCUSSION The motion pattern during compensatory postural adjustment is not related to quiet standing posture or to the final posture of compensatory postural adjustment. This fact should be considered when treating balance disturbances and musculoskeletal abnormalities. CONCLUSION Static posture cannot predict how body segments will behave during compensatory postural adjustment. PMID:19690665

  4. Assessing combined exposures of whole-body vibration and awkward posture--further results from application of a simultaneous field measurement methodology.

    PubMed

    Raffler, Nastaran; Hermanns, Ingo; Sayn, Detlef; Göres, Benno; Ellegast, Rolf; Rissler, Jörg

    2010-01-01

    The drivers of ten vehicles (tram, helicopter, saloon car, van, forklift, two mobile excavators, wheel loader, tractor, elevating platform truck) were studied with regard to the combined exposures of whole-body vibration and awkward posture during occupational tasks. Seven degrees of freedom (DOFs), or body angles, were recorded as a function of time by means of the CUELA measuring system (Computer-assisted registration and long-term analysis of musculoskeletal workloads) for the purpose of posture assessment. The vibrational exposure is expressed as the vector sum of the frequency-weighted accelerations in the three Cartesian coordinates; these were recorded simultaneously with the posture measurement. Based upon the percentage of working time spent under different workloads, a scheme is proposed for classification of the two exposures into three categories. In addition, a risk of adverse health effects classified as low, possible or high can be assigned to the combination of the two exposures. With regard to posture, the most severe exposure was measured for the drivers of the wheel loader and for the tractor driver, whereas the lowest exposure was measured for the helicopter pilots and van drivers. With regard to the combination of whole-body and posture exposures, the tractor driver and the elevating platform truck driver exhibited the highest workloads.

  5. Assessing combined exposures of whole-body vibration and awkward posture--further results from application of a simultaneous field measurement methodology.

    PubMed

    Raffler, Nastaran; Hermanns, Ingo; Sayn, Detlef; Göres, Benno; Ellegast, Rolf; Rissler, Jörg

    2010-01-01

    The drivers of ten vehicles (tram, helicopter, saloon car, van, forklift, two mobile excavators, wheel loader, tractor, elevating platform truck) were studied with regard to the combined exposures of whole-body vibration and awkward posture during occupational tasks. Seven degrees of freedom (DOFs), or body angles, were recorded as a function of time by means of the CUELA measuring system (Computer-assisted registration and long-term analysis of musculoskeletal workloads) for the purpose of posture assessment. The vibrational exposure is expressed as the vector sum of the frequency-weighted accelerations in the three Cartesian coordinates; these were recorded simultaneously with the posture measurement. Based upon the percentage of working time spent under different workloads, a scheme is proposed for classification of the two exposures into three categories. In addition, a risk of adverse health effects classified as low, possible or high can be assigned to the combination of the two exposures. With regard to posture, the most severe exposure was measured for the drivers of the wheel loader and for the tractor driver, whereas the lowest exposure was measured for the helicopter pilots and van drivers. With regard to the combination of whole-body and posture exposures, the tractor driver and the elevating platform truck driver exhibited the highest workloads. PMID:20953080

  6. Embodying approach motivation: body posture influences startle eyeblink and event-related potential responses to appetitive stimuli.

    PubMed

    Price, Tom F; Dieckman, Laurtiz W; Harmon-Jones, Eddie

    2012-07-01

    Past research suggested that the motivational significance of images influences reflexive and electrocortical responses to those images (Briggs and Martin, 2009; Gard et al., 2007; Schupp et al., 2004), with erotica often exerting the largest effects for appetitive pictures (Grillon and Baas, 2003; Weinberg and Hajcak, 2010). This research paradigm, however, compares responses to different types of images (e.g., erotica vs. exciting sports scenes). This past motivational interpretation, therefore, would be further supported by experiments wherein appetitive picture content is held constant and motivational states are manipulated with a different method. In the present experiment, we tested the hypothesis that changes in physical postures associated with approach motivation influences reflexive and electrocortical responses to appetitive stimuli. Past research has suggested that bodily manipulations (e.g., facial expressions) play a role in emotion- and motivation-related physiology (Ekman and Davidson, 1993; Levenson et al., 1990). Extending these results, leaning forward (associated with a heightened urge to approach stimuli) relative to reclining (associated with less of an urge to approach stimuli) caused participants to have smaller startle eyeblink responses during appetitive, but not neutral, picture viewing. Leaning relative to reclining also caused participants to have larger LPPs to appetitive but not neutral pictures, and influenced ERPs as early as 100ms into stimulus viewing. This evidence suggests that body postures associated with approach motivation causally influence basic reflexive and electrocortical reactions to appetitive emotive stimuli. PMID:22522185

  7. In-situ electric field in human body model in different postures for wireless power transfer system in an electrical vehicle.

    PubMed

    Shimamoto, Takuya; Laakso, Ilkka; Hirata, Akimasa

    2015-01-01

    The in-situ electric field of an adult male model in different postures is evaluated for exposure to the magnetic field leaked from a wireless power transfer system in an electrical vehicle. The transfer system is located below the centre of the vehicle body and the transferred power and frequency are 7 kW and 85 kHz, respectively. The in-situ electric field is evaluated for a human model (i) crouching near the vehicle, (ii) lying on the ground with or without his arm stretched, (iii) sitting in the driver's seat, and (iv) standing on a transmitting coil without a receiving coil. In each scenario, the maximum in-situ electric fields are lower than the allowable limit prescribed by international guidelines, although the local magnetic field strength in regions of the human body is higher than the allowable external magnetic field strength. The highest in-situ electric field is observed when the human body model is placed on the ground with his arm extended toward the coils, because of a higher magnetic field around the arm. PMID:25479377

  8. In-situ electric field in human body model in different postures for wireless power transfer system in an electrical vehicle.

    PubMed

    Shimamoto, Takuya; Laakso, Ilkka; Hirata, Akimasa

    2015-01-01

    The in-situ electric field of an adult male model in different postures is evaluated for exposure to the magnetic field leaked from a wireless power transfer system in an electrical vehicle. The transfer system is located below the centre of the vehicle body and the transferred power and frequency are 7 kW and 85 kHz, respectively. The in-situ electric field is evaluated for a human model (i) crouching near the vehicle, (ii) lying on the ground with or without his arm stretched, (iii) sitting in the driver's seat, and (iv) standing on a transmitting coil without a receiving coil. In each scenario, the maximum in-situ electric fields are lower than the allowable limit prescribed by international guidelines, although the local magnetic field strength in regions of the human body is higher than the allowable external magnetic field strength. The highest in-situ electric field is observed when the human body model is placed on the ground with his arm extended toward the coils, because of a higher magnetic field around the arm.

  9. In-situ electric field in human body model in different postures for wireless power transfer system in an electrical vehicle

    NASA Astrophysics Data System (ADS)

    Shimamoto, Takuya; Laakso, Ilkka; Hirata, Akimasa

    2015-01-01

    The in-situ electric field of an adult male model in different postures is evaluated for exposure to the magnetic field leaked from a wireless power transfer system in an electrical vehicle. The transfer system is located below the centre of the vehicle body and the transferred power and frequency are 7 kW and 85 kHz, respectively. The in-situ electric field is evaluated for a human model (i) crouching near the vehicle, (ii) lying on the ground with or without his arm stretched, (iii) sitting in the driver’s seat, and (iv) standing on a transmitting coil without a receiving coil. In each scenario, the maximum in-situ electric fields are lower than the allowable limit prescribed by international guidelines, although the local magnetic field strength in regions of the human body is higher than the allowable external magnetic field strength. The highest in-situ electric field is observed when the human body model is placed on the ground with his arm extended toward the coils, because of a higher magnetic field around the arm.

  10. Digital evaluation of sitting posture comfort in human-vehicle system under Industry 4.0 framework

    NASA Astrophysics Data System (ADS)

    Tao, Qing; Kang, Jinsheng; Sun, Wenlei; Li, Zhaobo; Huo, Xiao

    2016-09-01

    Most of the previous studies on the vibration ride comfort of the human-vehicle system were focused only on one or two aspects of the investigation. A hybrid approach which integrates all kinds of investigation methods in real environment and virtual environment is described. The real experimental environment includes the WBV(whole body vibration) test, questionnaires for human subjective sensation and motion capture. The virtual experimental environment includes the theoretical calculation on simplified 5-DOF human body vibration model, the vibration simulation and analysis within ADAMS/VibrationTM module, and the digital human biomechanics and occupational health analysis in Jack software. While the real experimental environment provides realistic and accurate test results, it also serves as core and validation for the virtual experimental environment. The virtual experimental environment takes full advantages of current available vibration simulation and digital human modelling software, and makes it possible to evaluate the sitting posture comfort in a human-vehicle system with various human anthropometric parameters. How this digital evaluation system for car seat comfort design is fitted in the Industry 4.0 framework is also proposed.

  11. Spatial cognition, body representation and affective processes: the role of vestibular information beyond ocular reflexes and control of posture

    PubMed Central

    Mast, Fred W.; Preuss, Nora; Hartmann, Matthias; Grabherr, Luzia

    2014-01-01

    A growing number of studies in humans demonstrate the involvement of vestibular information in tasks that are seemingly remote from well-known functions such as space constancy or postural control. In this review article we point out three emerging streams of research highlighting the importance of vestibular input: (1) Spatial Cognition: Modulation of vestibular signals can induce specific changes in spatial cognitive tasks like mental imagery and the processing of numbers. This has been shown in studies manipulating body orientation (changing the input from the otoliths), body rotation (changing the input from the semicircular canals), in clinical findings with vestibular patients, and in studies carried out in microgravity. There is also an effect in the reverse direction; top-down processes can affect perception of vestibular stimuli. (2) Body Representation: Numerous studies demonstrate that vestibular stimulation changes the representation of body parts, and sensitivity to tactile input or pain. Thus, the vestibular system plays an integral role in multisensory coordination of body representation. (3) Affective Processes and Disorders: Studies in psychiatric patients and patients with a vestibular disorder report a high comorbidity of vestibular dysfunctions and psychiatric symptoms. Recent studies investigated the beneficial effect of vestibular stimulation on psychiatric disorders, and how vestibular input can change mood and affect. These three emerging streams of research in vestibular science are—at least in part—associated with different neuronal core mechanisms. Spatial transformations draw on parietal areas, body representation is associated with somatosensory areas, and affective processes involve insular and cingulate cortices, all of which receive vestibular input. Even though a wide range of different vestibular cortical projection areas has been ascertained, their functionality still is scarcely understood. PMID:24904327

  12. Sports activities are reflected in the local stability and regularity of body sway: older ice-skaters have better postural control than inactive elderly.

    PubMed

    Lamoth, Claudine J C; van Heuvelen, Marieke J G

    2012-03-01

    With age postural control deteriorates and increases the risk for falls. Recent research has suggested that in contrast to persons with superior balance control (dancer's athletes), with pathology and aging, predictability and regularity of sway patterns increase and stability decreases implying a less adaptive form of postural control. The aim of the present study was to determine, whether patterns of body sway of elderly (N=13) who practice a sport which challenges postural control (ice speed-skating), are more similar to that of young subjects (N=10) than to that of inactive elderly (N=10). Trunk patterns were measured with a tri-axial accelerometer. Data were recorded during quiet upright stance with (1) eyes open, (2) limited vision, and (3) while performing a dual task. Anterior-posterior and medio-lateral acceleration time-series were analyzed. Differences in postural control were quantified in terms of the magnitude of the acceleration (root mean square), the smoothness (mean power frequency), the predictability (sample entropy) and the local stability (largest Lyapunov exponent). Postural control of ice-skating elderly differed from that of sedentary elderly. As anticipated, postural control of the ice-skating elderly was similar to that of young adults. For anterior-posterior accelerations, the skating elderly and the younger subjects had significant higher stability and lower regularity than the non-skating elderly in all tasks. These results imply that sport activities such as ice-skating are beneficial for elderly people. It might, at least partly, counteract the age related changes in postural control.

  13. Wide Eyes and Drooping Arms: Adult-Like Congruency Effects Emerge Early in the Development of Sensitivity to Emotional Faces and Body Postures

    ERIC Educational Resources Information Center

    Mondloch, Catherine J.; Horner, Matthew; Mian, Jasmine

    2013-01-01

    Adults' and 8-year-old children's perception of emotional faces is disrupted when faces are presented in the context of incongruent body postures (e.g., when a sad face is displayed on a fearful body) if the two emotions are highly similar (e.g., sad/fear) but not if they are highly dissimilar (e.g., sad/happy). The current research investigated…

  14. Evaluation of cervical posture following palatal expansion: a 12-month follow-up controlled study.

    PubMed

    Tecco, Simona; Caputi, Sergio; Festa, Felice

    2007-02-01

    This study evaluated the effects of rapid palatal expansion (RPE) on nasopharyngeal airway size, head posture, and cervical curvature angle in children with nasal obstruction. The patients were 45 female subjects (8-15 years of age) who had a reduced nasopharyngeal airway size and were subjectively assessed as being mouth breathers and requiring palatal expansion. They were randomly allocated to one of two groups: 23 subjects in the first group were treated with RPE, while the 22 subjects in the other group were monitored for approximately 14 months prior to commencing therapy, and became untreated controls. Lateral skull radiographs, taken in the natural head position, were obtained at the first visit (T0) and 6 (T1) and 12 (T2) months later for all subjects. The differences between the cephalometric variables at baseline and after 6 and 12 months were evaluated with a one-way repeated measures analysis of variance. Where significant interactions were found, a Bonferroni corrected paired Student's t-test was performed for pairwise comparisons. Changes in cephalometric variables within the experimental groups were tested by paired Student's t-tests as a post hoc procedure. Finally, a correlation matrix, using the Pearson correlation coefficient, was computed in order to evaluate the relationship between the change in airway adequacy and (1) the amount of maxillary expansion, (2) chronological age, (3) the amount of time that the appliance was activated, and (4) morphological and postural measurements of the face. At T1, children under active treatment showed a statistically significant increase in nasopharyngeal airway size, cervical curvature angle, and flexion of the head, together with a significant decrease in craniocervical angulation (all P < 0.05). These changes were all found to be stable at T2. No significant changes were seen in the control group. The correlation coefficients indicated a significant correlation between nasopharyngeal airway size and

  15. Effects of a Pilates exercise program on muscle strength, postural control and body composition: results from a pilot study in a group of post-menopausal women.

    PubMed

    Bergamin, M; Gobbo, S; Bullo, V; Zanotto, T; Vendramin, B; Duregon, F; Cugusi, L; Camozzi, V; Zaccaria, M; Neunhaeuserer, D; Ermolao, A

    2015-12-01

    Participation in exercise programs is heartily recommended for older adults since the level of physical fitness directly influences functional independence. The aim of this present study was to investigate the effects of supervised Pilates exercise training on the physical function, hypothesizing that a period of Pilates exercise training (PET) can increase overall muscle strength, body composition, and balance, during single and dual-task conditions, in a group of post-menopausal women. Twenty-five subjects, aged 59 to 66 years old, were recruited. Eligible participants were assessed prior and after 3 months of PET performed twice per week. Muscular strength was evaluated with handgrip strength (HGS) test, 30-s chair sit-to-stand test (30CST), and abdominal strength (AST) test. Postural control and dual-task performance were measured through a stabilometric platform while dynamic balance with 8 ft up and go test. Finally, body composition was assessed by means of dual-energy X-ray absorptiometry. Statistically significant improvements were detected on HGS (+8.22%), 30CST (+23.41%), 8 ft up and go test (-5.95%), AST (+30.81%), medio-lateral oscillations in open eyes and dual-task condition (-22.03% and -10.37%). Pilates was effective in increasing upper body, lower body, and abdominal muscle strength. No changes on body composition were detected. Results on this investigation indicated also that 12-week of mat Pilates is not sufficient to determine a clinical meaningful improvement on static balance in single and dual-task conditions. PMID:26578458

  16. Effects of a Pilates exercise program on muscle strength, postural control and body composition: results from a pilot study in a group of post-menopausal women.

    PubMed

    Bergamin, M; Gobbo, S; Bullo, V; Zanotto, T; Vendramin, B; Duregon, F; Cugusi, L; Camozzi, V; Zaccaria, M; Neunhaeuserer, D; Ermolao, A

    2015-12-01

    Participation in exercise programs is heartily recommended for older adults since the level of physical fitness directly influences functional independence. The aim of this present study was to investigate the effects of supervised Pilates exercise training on the physical function, hypothesizing that a period of Pilates exercise training (PET) can increase overall muscle strength, body composition, and balance, during single and dual-task conditions, in a group of post-menopausal women. Twenty-five subjects, aged 59 to 66 years old, were recruited. Eligible participants were assessed prior and after 3 months of PET performed twice per week. Muscular strength was evaluated with handgrip strength (HGS) test, 30-s chair sit-to-stand test (30CST), and abdominal strength (AST) test. Postural control and dual-task performance were measured through a stabilometric platform while dynamic balance with 8 ft up and go test. Finally, body composition was assessed by means of dual-energy X-ray absorptiometry. Statistically significant improvements were detected on HGS (+8.22%), 30CST (+23.41%), 8 ft up and go test (-5.95%), AST (+30.81%), medio-lateral oscillations in open eyes and dual-task condition (-22.03% and -10.37%). Pilates was effective in increasing upper body, lower body, and abdominal muscle strength. No changes on body composition were detected. Results on this investigation indicated also that 12-week of mat Pilates is not sufficient to determine a clinical meaningful improvement on static balance in single and dual-task conditions.

  17. Postural control in down syndrome: the use of somatosensory and visual information to attenuate body sway.

    PubMed

    Gomes, Matheus M; Barela, José A

    2007-07-01

    The purpose of this study was to examine the effects of visual and somatosensory information on body sway in individuals with Down syndrome (DS). Nine adults with DS (19-29 years old) and nine control subjects (CS) (19-29 years old) stood in the upright stance in four experimental conditions: no vision and no touch; vision and no touch; no vision and touch; and vision and touch. In the vision condition, participants looked at a target placed in front of them; in the no vision condition, participants wore a black cotton mask. In the touch condition, participants touched a stationary surface with their right index finger; in the no touch condition, participants kept their arms hanging alongside their bodies. A force plate was used to estimate center of pressure excursion for both anterior-posterior and medial-lateral directions. MANOVA revealed that both the individuals with DS and the control subjects used vision and touch to reduce overall body sway, although individuals with DS still oscillated more than did the CS. These results indicate that adults with DS are able to use sensory information to reduce body sway, and they demonstrate that there is no difference in sensory integration between the individuals with DS and the CS.

  18. Postural Control during Upper Body Locomotor-Like Movements: Similar Synergies Based on Dissimilar Muscle Modes

    PubMed Central

    Danna-Dos-Santos, Alessander; Shapkova, Elena Yu.; Shapkova, Alexandra L.; Degani, Adriana M.; Latash, Mark L.

    2009-01-01

    We studied the organization of leg and trunk muscles into groups (M-modes) and co-variation of M-mode involvement (M-mode synergies) during whole-body tasks associated with large variations of the moment of force about the vertical body axis. Our major questions were: (1) Can muscle activation patterns during such tasks be described with a few M-modes common across tasks and subjects? (2) Do these modes form the basis for synergies stabilizing MZ time pattern? (3) Will this organization differ between an explicit body rotation task and a task associated with locomotor-like alternating arm movements? Healthy subjects stood barefoot on the force platform and performed two motor tasks while paced by the metronome at 0.7, 1.0, and 1.4 Hz: Cyclic rotation of the upper body about the vertical body axis (body rotation task), and alternating rhythmic arm movements imitating those during running or quick walking (arm movement task). Principal component analysis was used to identify three M-modes within the space of integrated indices of muscle activity. The M-mode vectors showed clustering neither across subjects nor across frequencies. Variance in the M-mode space across sway cycles was partitioned into two components, one that did not affect the average value of MZ shift ("good variance") and the other that did. An index was computed reflecting the relative amount of the "good variance"; positive values of this index have been interpreted as reflecting a multi-M-mode synergy stabilizing the MZ trajectory. On average, the index was positive for both tasks and across all frequencies studied. However, the magnitude of the index was smaller for the intermediate frequency (1 Hz). The results show that the organization of muscles into groups during relatively complex whole-body tasks can differ significantly across both task variations and subjects. Nevertheless, the central nervous system seems to be able to build MZ stabilizing synergies based on different sets of M

  19. Skeletal and body composition evaluation

    NASA Technical Reports Server (NTRS)

    Mazess, R. B.

    1983-01-01

    Research on radiation detectors for absorptiometry; analysis of errors affective single photon absorptiometry and development of instrumentation; analysis of errors affecting dual photon absorptiometry and development of instrumentation; comparison of skeletal measurements with other techniques; cooperation with NASA projects for skeletal evaluation in spaceflight (Experiment MO-78) and in laboratory studies with immobilized animals; studies of postmenopausal osteoporosis; organization of scientific meetings and workshops on absorptiometric measurement; and development of instrumentation for measurement of fluid shifts in the human body were performed. Instrumentation was developed that allows accurate and precise (2% error) measurements of mineral content in compact and trabecular bone and of the total skeleton. Instrumentation was also developed to measure fluid shifts in the extremities. Radiation exposure with those procedures is low (2-10 MREM). One hundred seventy three technical reports and one hundred and four published papers of studies from the University of Wisconsin Bone Mineral Lab are listed.

  20. Posture modulates implicit hand maps.

    PubMed

    Longo, Matthew R

    2015-11-01

    Several forms of somatosensation require that afferent signals be informed by stored representations of body size and shape. Recent results have revealed that position sense relies on a highly distorted body representation. Changes of internal hand posture produce plastic alterations of processing in somatosensory cortex. This study therefore investigated how such postural changes affect implicit body representations underlying position sense. Participants localised the knuckles and tips of each finger in external space in two postures: the fingers splayed (Apart posture) or pressed together (Together posture). Comparison of the relative locations of the judgments of each landmark were used to construct implicit maps of represented hand structure. Spreading the fingers apart produced increases in the implicit representation of hand size, with no apparent effect on hand shape. Thus, changes of internal hand posture produce rapid modulation of how the hand itself is represented, paralleling the known effects on somatosensory cortical processing. PMID:26117153

  1. Posture modulates implicit hand maps.

    PubMed

    Longo, Matthew R

    2015-11-01

    Several forms of somatosensation require that afferent signals be informed by stored representations of body size and shape. Recent results have revealed that position sense relies on a highly distorted body representation. Changes of internal hand posture produce plastic alterations of processing in somatosensory cortex. This study therefore investigated how such postural changes affect implicit body representations underlying position sense. Participants localised the knuckles and tips of each finger in external space in two postures: the fingers splayed (Apart posture) or pressed together (Together posture). Comparison of the relative locations of the judgments of each landmark were used to construct implicit maps of represented hand structure. Spreading the fingers apart produced increases in the implicit representation of hand size, with no apparent effect on hand shape. Thus, changes of internal hand posture produce rapid modulation of how the hand itself is represented, paralleling the known effects on somatosensory cortical processing.

  2. On the importance of body posture and skin modelling with respect to in situ electric field strengths in magnetic field exposure scenarios

    NASA Astrophysics Data System (ADS)

    Schmid, Gernot; Hirtl, Rene

    2016-06-01

    The reference levels and maximum permissible exposure values for magnetic fields that are currently used have been derived from basic restrictions under the assumption of upright standing body models in a standard posture, i.e. with arms laterally down and without contact with metallic objects. Moreover, if anatomical modelling of the body was used at all, the skin was represented as a single homogeneous tissue layer. In the present paper we addressed the possible impacts of posture and skin modelling in scenarios of exposure to a 50 Hz uniform magnetic field on the in situ electric field strength in peripheral tissues, which must be limited in order to avoid peripheral nerve stimulation. We considered different body postures including situations where body parts form large induction loops (e.g. clasped hands) with skin-to-skin and skin-to-metal contact spots and compared the results obtained with a homogeneous single-layer skin model to results obtained with a more realistic two-layer skin representation consisting of a low-conductivity stratum corneum layer on top of a combined layer for the cellular epidermis and dermis. Our results clearly indicated that postures with loops formed of body parts may lead to substantially higher maximum values of induced in situ electric field strengths than in the case of standard postures due to a highly concentrated current density and in situ electric field strength in the skin-to-skin and skin-to-metal contact regions. With a homogeneous single-layer skin, as is used for even the most recent anatomical body models in exposure assessment, the in situ electric field strength may exceed the basic restrictions in such situations, even when the reference levels and maximum permissible exposure values are not exceeded. However, when using the more realistic two-layer skin model the obtained in situ electric field strengths were substantially lower and no violations of the basic restrictions occurred, which can be explained by the

  3. Body image inflexibility mediates the relationship between body image evaluation and maladaptive body image coping strategies.

    PubMed

    Mancuso, Serafino G

    2016-03-01

    Body image inflexibility, the unwillingness to experience negative appearance-related thoughts and emotions, is associated with negative body image and eating disorder symptoms. The present study investigated whether body image inflexibility mediated the relationship between body image evaluation and maladaptive body image coping strategies (appearance-fixing and experiential avoidance) in a college and community sample comprising 156 females aged 18-51 years (M=22.76, SD=6.96). Controlling for recruitment source (college vs. community), body image inflexibility fully mediated the relationship between body image evaluation and maladaptive body image coping strategies. Results indicated that an unwillingness to experience negative appearance-related thoughts and emotions is likely responsible for negative body image evaluation's relationship to appearance-fixing behaviours and experiential avoidance. Findings support extant evidence that interventions that explicitly target body image inflexibility, such as Acceptance and Commitment Therapy, may have utility in treating body dissatisfaction in nonclinical populations. PMID:26595857

  4. Body image inflexibility mediates the relationship between body image evaluation and maladaptive body image coping strategies.

    PubMed

    Mancuso, Serafino G

    2016-03-01

    Body image inflexibility, the unwillingness to experience negative appearance-related thoughts and emotions, is associated with negative body image and eating disorder symptoms. The present study investigated whether body image inflexibility mediated the relationship between body image evaluation and maladaptive body image coping strategies (appearance-fixing and experiential avoidance) in a college and community sample comprising 156 females aged 18-51 years (M=22.76, SD=6.96). Controlling for recruitment source (college vs. community), body image inflexibility fully mediated the relationship between body image evaluation and maladaptive body image coping strategies. Results indicated that an unwillingness to experience negative appearance-related thoughts and emotions is likely responsible for negative body image evaluation's relationship to appearance-fixing behaviours and experiential avoidance. Findings support extant evidence that interventions that explicitly target body image inflexibility, such as Acceptance and Commitment Therapy, may have utility in treating body dissatisfaction in nonclinical populations.

  5. Assessment of postural balance function.

    PubMed

    Kostiukow, Anna; Rostkowska, Elzbieta; Samborski, Włodzimierz

    2009-01-01

    Postural balance is defined as the ability to stand unassisted without falling. Examination of the patient's postural balance function is a difficult diagnostic task. Most of the balance tests used in medicine provide incomplete information on this coordination ability of the human body. The aim of this study was to review methods of assessment of the patient's postural balance function, including various tests used in medical diagnostics centers. PMID:20698188

  6. Assessment of postural balance function.

    PubMed

    Kostiukow, Anna; Rostkowska, Elzbieta; Samborski, Włodzimierz

    2009-01-01

    Postural balance is defined as the ability to stand unassisted without falling. Examination of the patient's postural balance function is a difficult diagnostic task. Most of the balance tests used in medicine provide incomplete information on this coordination ability of the human body. The aim of this study was to review methods of assessment of the patient's postural balance function, including various tests used in medical diagnostics centers.

  7. Evaluation of Body Composition: Why and How?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Evaluation of human body composition in vivo remains a critical component in the assessment of nutritional status of an individual.Whereas traditional measurements of standing height and body weight provide information on body mass index and, hence, the risk of some chronic diseases, advanced techno...

  8. Evaluation of Two New Indices of Blood Pressure Variability Using Postural Change in Older Fallers

    PubMed Central

    Goh, Choon-Hian; Ng, Siew-Cheok; Kamaruzzaman, Shahrul B.; Chin, Ai-Vyrn; Poi, Philip J. H.; Chee, Kok Han; Imran, Z. Abidin; Tan, Maw Pin

    2016-01-01

    Abstract To evaluate the utility of blood pressure variability (BPV) calculated using previously published and newly introduced indices using the variables falls and age as comparators. While postural hypotension has long been considered a risk factor for falls, there is currently no documented evidence on the relationship between BPV and falls. A case-controlled study involving 25 fallers and 25 nonfallers was conducted. Systolic (SBPV) and diastolic blood pressure variability (DBPV) were assessed using 5 indices: standard deviation (SD), standard deviation of most stable continuous 120 beats (staSD), average real variability (ARV), root mean square of real variability (RMSRV), and standard deviation of real variability (SDRV). Continuous beat-to-beat blood pressure was recorded during 10 minutes’ supine rest and 3 minutes’ standing. Standing SBPV was significantly higher than supine SBPV using 4 indices in both groups. The standing-to-supine-BPV ratio (SSR) was then computed for each subject (staSD, ARV, RMSRV, and SDRV). Standing-to-supine ratio for SBPV was significantly higher among fallers compared to nonfallers using RMSRV and SDRV (P = 0.034 and P = 0.025). Using linear discriminant analysis (LDA), 3 indices (ARV, RMSRV, and SDRV) of SSR SBPV provided accuracies of 61.6%, 61.2%, and 60.0% for the prediction of falls which is comparable with timed-up and go (TUG), 64.4%. This study suggests that SSR SBPV using RMSRV and SDRV is a potential predictor for falls among older patients, and deserves further evaluation in larger prospective studies. PMID:27175670

  9. Common postural defects among music students.

    PubMed

    Blanco-Piñeiro, Patricia; Díaz-Pereira, M Pino; Martínez, Aurora

    2015-07-01

    Postural quality during musical performance affects both musculoskeletal health and the quality of the performance. In this study we examined the posture of 100 students at a Higher Conservatory of Music in Spain. By analysing video tapes and photographs of the students while performing, a panel of experts extracted values of 11 variables reflecting aspects of overall postural quality or the postural quality of various parts of the body. The most common postural defects were identified, together with the situations in which they occur. It is concluded that most students incur in unphysiological postures during performance. It is hoped that use of the results of this study will help correct these errors.

  10. Real-time posture reconstruction for Microsoft Kinect.

    PubMed

    Shum, Hubert P H; Ho, Edmond S L; Jiang, Yang; Takagi, Shu

    2013-10-01

    The recent advancement of motion recognition using Microsoft Kinect stimulates many new ideas in motion capture and virtual reality applications. Utilizing a pattern recognition algorithm, Kinect can determine the positions of different body parts from the user. However, due to the use of a single-depth camera, recognition accuracy drops significantly when the parts are occluded. This hugely limits the usability of applications that involve interaction with external objects, such as sport training or exercising systems. The problem becomes more critical when Kinect incorrectly perceives body parts. This is because applications have limited information about the recognition correctness, and using those parts to synthesize body postures would result in serious visual artifacts. In this paper, we propose a new method to reconstruct valid movement from incomplete and noisy postures captured by Kinect. We first design a set of measurements that objectively evaluates the degree of reliability on each tracked body part. By incorporating the reliability estimation into a motion database query during run time, we obtain a set of similar postures that are kinematically valid. These postures are used to construct a latent space, which is known as the natural posture space in our system, with local principle component analysis. We finally apply frame-based optimization in the space to synthesize a new posture that closely resembles the true user posture while satisfying kinematic constraints. Experimental results show that our method can significantly improve the quality of the recognized posture under severely occluded environments, such as a person exercising with a basketball or moving in a small room. PMID:23981562

  11. Real-time posture reconstruction for Microsoft Kinect.

    PubMed

    Shum, Hubert P H; Ho, Edmond S L; Jiang, Yang; Takagi, Shu

    2013-10-01

    The recent advancement of motion recognition using Microsoft Kinect stimulates many new ideas in motion capture and virtual reality applications. Utilizing a pattern recognition algorithm, Kinect can determine the positions of different body parts from the user. However, due to the use of a single-depth camera, recognition accuracy drops significantly when the parts are occluded. This hugely limits the usability of applications that involve interaction with external objects, such as sport training or exercising systems. The problem becomes more critical when Kinect incorrectly perceives body parts. This is because applications have limited information about the recognition correctness, and using those parts to synthesize body postures would result in serious visual artifacts. In this paper, we propose a new method to reconstruct valid movement from incomplete and noisy postures captured by Kinect. We first design a set of measurements that objectively evaluates the degree of reliability on each tracked body part. By incorporating the reliability estimation into a motion database query during run time, we obtain a set of similar postures that are kinematically valid. These postures are used to construct a latent space, which is known as the natural posture space in our system, with local principle component analysis. We finally apply frame-based optimization in the space to synthesize a new posture that closely resembles the true user posture while satisfying kinematic constraints. Experimental results show that our method can significantly improve the quality of the recognized posture under severely occluded environments, such as a person exercising with a basketball or moving in a small room.

  12. Evaluating Behavioral Self-Monitoring with Accuracy Training for Changing Computer Work Postures

    ERIC Educational Resources Information Center

    Gravina, Nicole E.; Loewy, Shannon; Rice, Anna; Austin, John

    2013-01-01

    The primary purpose of this study was to replicate and extend a study by Gravina, Austin, Schroedter, and Loewy (2008). A similar self-monitoring procedure, with the addition of self-monitoring accuracy training, was implemented to increase the percentage of observations in which participants worked in neutral postures. The accuracy training…

  13. The effect of a short-term and long-term whole-body vibration in healthy men upon the postural stability.

    PubMed

    Piecha, Magdalena; Juras, Grzegorz; Król, Piotr; Sobota, Grzegorz; Polak, Anna; Bacik, Bogdan

    2014-01-01

    The study aimed to establish the short-term and long-term effects of whole-body vibration on postural stability. The sample consisted of 28 male subjects randomly allocated to four comparative groups, three of which exercised on a vibration platform with parameters set individually for the groups. The stabilographic signal was recorded before the test commenced, after a single session of whole-body vibration, immediately after the last set of exercises of the 4-week whole-body vibration training, and one week after the training ended. The subjects were exposed to vibrations 3 times a week for 4 weeks. Long-term vibration training significantly shortened the rambling and trembling paths in the frontal plane. The path lengths were significantly reduced in the frontal plane one week after the training end date. Most changes in the values of the center of pressure (COP) path lengths in the sagittal and frontal plane were statistically insignificant. We concluded that long-term vibration training improves the postural stability of young healthy individuals in the frontal plane.

  14. Postural strategies assessed with inertial sensors in healthy and parkinsonian subjects

    PubMed Central

    Baston, Chiara; Mancini, Martina; Schoneburg, Bernadette; Horak, Fay; Rocchi, Laura

    2015-01-01

    The present study introduces a novel instrumented method to characterize postural movement strategies to maintain balance during stance (ankle and hip strategy), by means of inertial sensors, positioned on the legs and on the trunk. We evaluated postural strategies in subjects with2 types of parkinsonism: idiopathic Parkinson's disease (PD) and Progressive Supranuclear Palsy (PSP),and inage-matched control subjects standing under perturbed conditions implementedby the Sensory Organization Test (SOT).Coordination between the upper and lower segments of the body during postural sway was measured using a covariance index over time, by a sliding-window algorithm. Afterwards, a postural strategy index was computed. We also measuredthe amount of postural sway, as adjunctive information to characterize balance, by the root mean square of the horizontal trunk acceleration signal (RMS). Results showed that control subjects were able to change their postural strategy, whilst PSP and PD subjects persisted in use of an ankle strategy in all conditions.PD subjects had RMS values similar to control subjects even without changing postural strategy appropriately, whereas PSP subjects showed much larger RMS values than controls, resulting in several falls during the most challenging SOT conditions (5 and 6). Results are in accordance with the corresponding clinical literature describing postural behavior in the same kind of subjects. The proposed strategy index, based on the use ofinertial sensors on the upper and lower body segments, isa promising and unobtrusive toolto characterize postural strategies performed to attain balance. PMID:24656713

  15. Non invasive continuous hemodynamic evaluation of cirrhotic patients after postural challenge

    PubMed Central

    Tarquini, Roberto; Mazzoccoli, Gianluigi; Fusi, Fulvio; Laffi, Giacomo; Gensini, Gian Franco; Romano, Salvatore Mario

    2012-01-01

    AIM: To assess whether Most Care is able to detect the cardiovascular alterations in response to physiological stress (posture). METHODS: Non invasive hemodynamic was assessed in 26 cirrhotic patients compared to healthy subjects, both in the supine and standing positions. RESULTS: In baseline conditions, when compared to healthy subjects, cirrhotic patients showed significantly lower values of dicrotic and diastolic pressures and systemic vascular resistance. While in the standing position, cirrhotic patients showed higher values of cardiac index, stroke volume index and cardiac cycle efficiency. When returning to the supine position, cirrhotic patients exhibited lower values of dicrotic and diastolic pressures and systemic vascular resistance in the presence of higher values of cardiac index, stroke volume index and cardiac cycle efficiency. CONCLUSION: Most Care proved to be able to detect cardiovascular abnormalities bedside in the resting state and after postural challenge in cirrhotic patients. PMID:22567187

  16. Postural stress analysis in industry.

    PubMed

    Genaidy, A M; Al-Shedi, A A; Karwowski, W

    1994-04-01

    Both observational and instrumentation-based techniques have been used to conduct postural stress analysis in industry. As observational methods are more widespread than instrumentation-based techniques and can be used as a practical tool in the workplace, this study reviews and assesses the scientific literature on observational techniques. Techniques are classified into macropostural, micropostural and postural-work activity. The basis for each classification is outlined and evaluated. Postural recording is performed either continuously or intermittently. Intermittent postural recording procedures lack the criteria for determining the optimum number of observations for low and high repetitive jobs. Research is warranted to examine the sources and magnitudes of errors associated with postural classification. Such information is required to train job analysts in the ergonomics of working postures. PMID:15676953

  17. Postural Stability During Single-Leg Stance: A Preliminary Evaluation of Noncontact Lower Extremity Injury Risk.

    PubMed

    Dingenen, Bart; Malfait, Bart; Nijs, Stefaan; Peers, Koen H E; Vereecken, Styn; Verschueren, Sabine M P; Janssens, Luc; Staes, Filip F

    2016-08-01

    Study Design Controlled laboratory study with a prospective cohort design. Background Postural stability deficits during single-leg stance have been reported in persons with anterior cruciate ligament (ACL) injury, ACL reconstruction, and chronic ankle instability. It remains unclear whether impaired postural stability is a consequence or cause of these injuries. Objectives To prospectively investigate whether postural stability deficits during single-leg stance predict noncontact lower extremity injuries. Methods Fifty injury-free female athletes performed a transition task from double-leg stance to single-leg stance with eyes closed. Center-of-pressure displacement, the main outcome variable, was measured during the first 3 seconds after the time to a new stability point was reached during single-leg stance. Noncontact lower extremity injuries were recorded at a 1-year follow-up. Results Six participants sustained a noncontact ACL injury or ankle sprain. Center-of-pressure displacement during the first 3 seconds after the time to a new stability point was significantly increased in the injured (P = .030) and noninjured legs (P = .009) of the injured group compared to the respective matched legs of the noninjured group. The area under the receiver operating characteristic curve (AUC) analysis revealed significant discriminative accuracy between groups for the center-of-pressure displacement during the first 3 seconds after the time to a new stability point of the injured (AUC = 0.814, P = .015) and noninjured legs (AUC = 0.897, P = .004) of the injured group compared to the matched legs of the noninjured group. Conclusion This preliminary study suggests that postural stability measurements during the single-leg stance phase of the double- to single-leg stance transition task may be a useful predictor of increased risk of noncontact lower extremity injury. Further research is indicated. Level of Evidence Prognosis, level 4. J Orthop Sports PhysTher 2016

  18. Factors affecting the perception of whole-body vibration of occupational drivers: an analysis of posture and manual materials handling and musculoskeletal disorders

    PubMed Central

    Raffler, Nastaran; Ellegast, Rolf; Kraus, Thomas; Ochsmann, Elke

    2016-01-01

    Due to the high cost of conducting field measurements, questionnaires are usually preferred for the assessment of physical workloads and musculoskeletal disorders (MSDs). This study compares the physical workloads of whole-body vibration (WBV) and awkward postures by direct field measurements and self-reported data of 45 occupational drivers. Manual materials handling (MMH) and MSDs were also investigated to analyse their effect on drivers' perception. Although the measured values for WBV exposure were very similarly distributed among the drivers, the subjects' perception differed significantly. Concerning posture, subjects seemed to estimate much better when the difference in exposure was significantly large. The percentage of measured awkward trunk and head inclination were significantly higher for WBV-overestimating subjects than non-overestimators; 77 and 80% vs. 36 and 33%. Health complaints in terms of thoracic spine, cervical spine and shoulder–arm were also significantly more reported by WBV-overestimating subjects (42, 67, 50% vs. 0, 25, 13%, respectively). Although more MMH was reported by WBV-overestimating subjects, there was no statistical significance in this study. PMID:26114619

  19. Comparison of Standing Posture Bioelectrical Impedance Analysis with DXA for Body Composition in a Large, Healthy Chinese Population

    PubMed Central

    Chen, Kuen-Tsann; Chen, Yu-Yawn; Wang, Chia-Wei; Chuang, Chih-Lin; Chiang, Li-Ming; Lai, Chung-Liang; Lu, Hsueh-Kuan; Dwyer, Gregory B.; Chao, Shu-Ping; Shih, Ming-Kuei; Hsieh, Kuen-Chang

    2016-01-01

    Bioelectrical impedance analysis (BIA) is a common method for assessing body composition in research and clinical trials. BIA is convenient but when compared with other reference methods, the results have been inconclusive. The level of obesity degree in subjects is considered to be an important factor affecting the accuracy of the measurements. A total of 711 participants were recruited in Taiwan and were sub-grouped by gender and levels of adiposity. Regression analysis and Bland-Altman analysis were used to evaluate the agreement of the measured body fat percentage (BF%) between BIA and DXA. The BF% measured by the DXA and BIA methods (Tanita BC-418) were expressed as BF%DXA and BF%BIA8, respectively. A one-way ANOVA was used to test the differences in BF% measurements by gender and levels of adiposity. The estimated BF%BIA8 and BF%DXA in the all subjects, male and female groups were all highly correlated (r = 0.934, 0.901, 0.916, all P< 0.001). The average estimated BF%BIA8 (22.54 ± 9.48%) was significantly lower than the average BF%DXA (26.26 ± 11.18%). The BF%BIA8 was overestimated in the male subgroup (BF%DXA< 15%), compared to BF%DXA by 0.45%, respectively. In the other subgroups, the BF%BIA8 values were all underestimated. Standing BIA estimating body fat percentage in Chinese participants have a high correlation, but underestimated on normal and high obesity degree in both male and female subjects. PMID:27467065

  20. Comparison of Standing Posture Bioelectrical Impedance Analysis with DXA for Body Composition in a Large, Healthy Chinese Population.

    PubMed

    Chen, Kuen-Tsann; Chen, Yu-Yawn; Wang, Chia-Wei; Chuang, Chih-Lin; Chiang, Li-Ming; Lai, Chung-Liang; Lu, Hsueh-Kuan; Dwyer, Gregory B; Chao, Shu-Ping; Shih, Ming-Kuei; Hsieh, Kuen-Chang

    2016-01-01

    Bioelectrical impedance analysis (BIA) is a common method for assessing body composition in research and clinical trials. BIA is convenient but when compared with other reference methods, the results have been inconclusive. The level of obesity degree in subjects is considered to be an important factor affecting the accuracy of the measurements. A total of 711 participants were recruited in Taiwan and were sub-grouped by gender and levels of adiposity. Regression analysis and Bland-Altman analysis were used to evaluate the agreement of the measured body fat percentage (BF%) between BIA and DXA. The BF% measured by the DXA and BIA methods (Tanita BC-418) were expressed as BF%DXA and BF%BIA8, respectively. A one-way ANOVA was used to test the differences in BF% measurements by gender and levels of adiposity. The estimated BF%BIA8 and BF%DXA in the all subjects, male and female groups were all highly correlated (r = 0.934, 0.901, 0.916, all P< 0.001). The average estimated BF%BIA8 (22.54 ± 9.48%) was significantly lower than the average BF%DXA (26.26 ± 11.18%). The BF%BIA8 was overestimated in the male subgroup (BF%DXA< 15%), compared to BF%DXA by 0.45%, respectively. In the other subgroups, the BF%BIA8 values were all underestimated. Standing BIA estimating body fat percentage in Chinese participants have a high correlation, but underestimated on normal and high obesity degree in both male and female subjects. PMID:27467065

  1. Postural control during lifting.

    PubMed

    Kollmitzer, Josef; Oddsson, L; Ebenbichler, G R; Giphart, J E; DeLuca, C J

    2002-05-01

    Any voluntary motion of the body causes an internal perturbation of balance. Load transfer during manual material handling may increase these perturbations. This study investigates effects of stance condition on postural control during lifting. Nineteen healthy subjects repeatedly lifted and lowered a load between a desk and a shelf. The base of support was varied between parallel and step stance. Ground reaction force and segmental kinematics were measured. Load transfer during lifting perturbed balance. In parallel stance postural response consisted of axial movements in the sagittal plane. Such strategy was accompanied by increased posterior shear forces after lift-off. Lifting in step stance provided extended support in anterior/posterior direction. The postural control mechanisms in the sagittal plane are less complex as compared to parallel stance. However, lifting in step stance was asymmetrical and thus accompanied by distinct lateral transfer of the body. Lateral shear forces were larger as compared to parallel stance. Both lifting techniques exhibit positive and negative aspects. We cannot recommend either one as being better in terms of postural control.

  2. Postural Control in Children with Autism.

    ERIC Educational Resources Information Center

    Kohen-Raz, Reuven; And Others

    1992-01-01

    Postural control was evaluated in 91 autistic, 166 normal, and 18 mentally retarded children using a computerized posturographic procedure. In comparison to normal children, the autistic subjects were less likely to exhibit age-related changes in postural performance, and postures were more variable and less stable. (Author/JDD)

  3. Postural Variables in Girls Practicing Volleyball

    ERIC Educational Resources Information Center

    Grabara, Malgorzata; Hadzik, Andrzej

    2009-01-01

    Study aim: To assess body posture of young female volleyball players in relation to their untrained mates. Material and methods: A group of 42 volleyball players and another of 43 untrained girls, all aged 13-16 years were studied with respect to their body posture indices by using computer posturography. Spinal angles and curvatures were…

  4. Postural Stability is Altered by Blood Shift

    NASA Astrophysics Data System (ADS)

    Marais, M.; Denise, P.; Guincetre, J. Y.; Normand, H.

    2008-06-01

    Non-vestibular influences as shift in blood volume changed perception of body posture. Then, factors affecting blood shift may alter postural control. The purpose of our study was to investigate the effects of leg venous contention on postural stability. Twelve subjects were studied on a balance plate for 5 minutes with the eyes closed, in 3 conditions: with no leg venous contention or grade 1 and 3 support stockings. Standard deviation of x and y position was calculated before and after the closure of the eyes. Strong venous contention altered postural stability, after the eyes were closed, during the first 10 s of standing. As support stockings prevent blood shift induced by upright posture, this result is in line with the hypothesis that blood shifts influence the perception of body orientation and postural control among others factors as vision, vestibular inputs... This strong venous contention could induce an increase of fall.

  5. 42 CFR 8.5 - Periodic evaluation of accreditation bodies.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false Periodic evaluation of accreditation bodies. 8.5... accreditation bodies. SAMHSA will evaluate periodically the performance of accreditation bodies primarily by inspecting a selected sample of the OTPs accredited by the accrediting body and by evaluating...

  6. 42 CFR 8.5 - Periodic evaluation of accreditation bodies.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Periodic evaluation of accreditation bodies. 8.5... accreditation bodies. SAMHSA will evaluate periodically the performance of accreditation bodies primarily by inspecting a selected sample of the OTPs accredited by the accrediting body and by evaluating...

  7. Coupling of postural activity with motion of a ship at sea.

    PubMed

    Varlet, Manuel; Bardy, Benoît G; Chen, Fu-Chen; Alcantara, Cristina; Stoffregen, Thomas A

    2015-05-01

    On land, body sway during stance becomes coupled with imposed oscillations of the illuminated environment or of the support surface. This coupling appears to have the function of stabilizing the body relative to the illuminated or inertial environment. In previous research, the stimulus has been limited to motion in a single axis. Little is known about our ability to couple postural activity with complex, multi-axis oscillations. On a ship at sea, we evaluated postural activity using measures of body movement, as such, and we separately evaluated a direct measure of coupling between body movement and ship motion. Participants were tested while facing fore-aft and athwartship. We compared postural activity between participants who had been seasick at the beginning of the voyage and those who had not. Coupling of postural activity with ship motion differed between body axes as a function of body orientation relative to the ship. In addition, coupling differed between participants who had been seasick at the beginning of the voyage and those who had not. We discuss the results in terms of implications for general theories of postural control, and for prediction of susceptibility to seasickness in individuals.

  8. Effects of adiposity on postural control and cognition.

    PubMed

    Meng, Hao; O'Connor, Daniel P; Lee, Beom-Chan; Layne, Charles S; Gorniak, Stacey L

    2016-01-01

    In the U.S., it is estimated that over one-third of adults are obese (Body Mass Index (BMI)>30kg/m(2)). Previous studies suggest that obesity may be associated with deficits in cognitive performance and postural control. Increased BMI may challenge cognitive and postural performance in a variety of populations; however, most relevant studies have classified participants based on BMI values, which cannot be used to accurately assess the effects of adiposity on cognitive performance and postural control. The objective of the current study was to examine motor and cognitive responses for overweight and obese adults compared to normal weight individuals by using both BMI and adiposity measures. Ten normal weight (BMI=18-24.9kg/m(2)), ten overweight (BMI=25-29.9kg/m(2)), and ten obese (BMI=30-40kg/m(2)) adults were evaluated (age: 24±4 years). Participants were classified into three groups based on BMI values at the onset of the study, prior to body composition analysis. Participants performed (1) working memory task while maintaining upright stance, and (2) a battery of sensorimotor evaluations. Working memory reaction times, response accuracy, center-of-pressure (COP) path length, velocity, migration area, time to boundary values in anterior-posterior direction, and ankle-hip strategy-scores were calculated to evaluate cognitive-motor performance. No significant deficits in working memory performance were observed. Overall, measures of motor function deteriorated as BMI and body fat percentage increased. The relationship between deteriorating postural performance indices and body fat percentage were greater than those found between BMI and postural performance indices.

  9. Dynamical Origins of Stereotypy: Relation of Postural Movements during Sitting to Stereotyped Movements during Body-Rocking

    ERIC Educational Resources Information Center

    Newell, Karl M.; Bodfish, James W.

    2007-01-01

    The relation between the movement dynamic properties of sitting still and of seated body-rocking in adults with stereotyped movement disorder and mental retardation and a contrast group of typically developing age-matched adults was examined. Continuous measurement of sequential displacements in center-of-pressure was made using a force platform…

  10. Simulating Non-Specific Influences of Body Posture and Temperature on Thigh-Bioimpedance Spectroscopy during Continuous Monitoring Applications

    NASA Astrophysics Data System (ADS)

    Ismail, A. H.; Leonhardt, S.

    2013-04-01

    Application of bioimpedance spectroscopy (BIS) for continuous monitoring of body fluid volumes is gaining considerable importance in personal health care. Unless laboratory conditions are applied, both whole-body or segmental BIS configurations are subject to nonspecific influences (e.g. temperature and change in body position) reducing the method's accuracy and reproducibility. In this work, a two-compartment mathematical model, which describes the thigh segment, has been adapted to simulate fluid and solute kinetics during change in body position or variation in skin temperature. The model is an improved version of our previous one offering a good tradeoff between accuracy and simplicity. It represents the kinetics of fluid redistribution, sodium-, potassium-, and protein-concentrations based on simple equations to predict the time course of BIS variations. Validity of the model was verified in five subjects (following a sequence of 7 min supine, 20 min standing, and 40 min supine). The output of the model may reduce possible influences on BIS by up to 80%.

  11. Effects of an adapted physical activity program in a group of elderly subjects with flexed posture: clinical and instrumental assessment

    PubMed Central

    Benedetti, Maria Grazia; Berti, Lisa; Presti, Chiara; Frizziero, Antonio; Giannini, Sandro

    2008-01-01

    Background Flexed posture commonly increases with age and is related to musculoskeletal impairment and reduced physical performance. The purpose of this clinical study was to systematically compare the effects of a physical activity program that specifically address the flexed posture that marks a certain percentage of elderly individuals with a non specific exercise program for 3 months. Methods Participants were randomly divided into two groups: one followed an Adapted Physical Activity program for flexed posture and the other one completed a non-specific physical activity protocol for the elderly. A multidimensional clinical assessment was performed at baseline and at 3 months including anthropometric data, clinical profile, measures of musculoskeletal impairment and disability. The instrumental assessment of posture was realized using a stereophotogrammetric system and a specific biomechanical model designed to describe the reciprocal position of the body segments on the sagittal plane in a upright posture. Results The Adapted Physical Activity program determined a significant improvement in several key parameters of the multidimensional assessment in comparison to the non-specific protocol: decreased occiput-to-wall distance, greater lower limb range of motion, better flexibility of pectoralis, hamstrings and hip flexor muscles, increased spine extensor muscles strength. Stereophotogrammetric analysis confirmed a reduced protrusion of the head and revealed a reduction in compensative postural adaptations to flexed posture characterized by knee flexion and ankle dorsiflexion in the participants of the specific program. Conclusion The Adapted Physical Activity program for flexed posture significantly improved postural alignment and musculoskeletal impairment of the elderly. The stereophotogrammetric evaluation of posture was useful to measure the global postural alignment and especially to analyse the possible compensatory strategies at lower limbs in flexed

  12. Analysis of the risk factors of musculoskeletal disease among dentists induced by work posture

    PubMed Central

    Park, Hyun-Suk; Kim, Jin; Roh, Hyo-Lyun; Namkoong, Seung

    2015-01-01

    [Purpose] The purpose of this study was to ergonomically evaluate the work posture of dentists to examine their subsequent risk of developing musculoskeletal diseases. [Subjects and Methods] Scenes in which the three dentists performed procedures at their dental clinics were videotaped. The videotapes of the dentists’ work postures were evaluated and analyzed by using the Rapid Upper Limb Assessment (RULA) and Quick Exposure Check (QEC). [Results] The RULA analysis of the dentists’ work posture indicated, “improvement required” in the posture used to treat the anterior and “instant improvement required” in the posture used to treat the maxillary second molar. Of all the work postures studied, the risk was considered particularly high in the lower back and neck, implying prominent problems in these body parts. The QEC analysis showed that the worst work posture was that required to treat the maxillary second molar, which led to a high risk of neck problems and vibrations. [Conclusion] The neck area has the highest risk of developing musculoskeletal disease. Hence, regular rests and the provision of information regarding muscle strengthening exercise for the neck are necessary. PMID:26834324

  13. Common postural defects among music students.

    PubMed

    Blanco-Piñeiro, Patricia; Díaz-Pereira, M Pino; Martínez, Aurora

    2015-07-01

    Postural quality during musical performance affects both musculoskeletal health and the quality of the performance. In this study we examined the posture of 100 students at a Higher Conservatory of Music in Spain. By analysing video tapes and photographs of the students while performing, a panel of experts extracted values of 11 variables reflecting aspects of overall postural quality or the postural quality of various parts of the body. The most common postural defects were identified, together with the situations in which they occur. It is concluded that most students incur in unphysiological postures during performance. It is hoped that use of the results of this study will help correct these errors. PMID:26118530

  14. Imaging Posture Veils Neural Signals

    PubMed Central

    Thibault, Robert T.; Raz, Amir

    2016-01-01

    Whereas modern brain imaging often demands holding body positions incongruent with everyday life, posture governs both neural activity and cognitive performance. Humans commonly perform while upright; yet, many neuroimaging methodologies require participants to remain motionless and adhere to non-ecological comportments within a confined space. This inconsistency between ecological postures and imaging constraints undermines the transferability and generalizability of many a neuroimaging assay. Here we highlight the influence of posture on brain function and behavior. Specifically, we challenge the tacit assumption that brain processes and cognitive performance are comparable across a spectrum of positions. We provide an integrative synthesis regarding the increasingly prominent influence of imaging postures on autonomic function, mental capacity, sensory thresholds, and neural activity. Arguing that neuroimagers and cognitive scientists could benefit from considering the influence posture wields on both general functioning and brain activity, we examine existing imaging technologies and the potential of portable and versatile imaging devices (e.g., functional near infrared spectroscopy). Finally, we discuss ways that accounting for posture may help unveil the complex brain processes of everyday cognition.

  15. Dynamic postural stability for double-leg drop landing.

    PubMed

    Niu, Wenxin; Zhang, Ming; Fan, Yubo; Zhao, Qinping

    2013-01-01

    Dynamic postural stability has been widely studied for single-leg landing, but seldom considered for double-leg landing. This study aimed to evaluate the dynamic postural stability and the influence mechanism of muscle activities during double-leg drop landing. Eight recreationally active males and eight recreationally active females participated in this study and dropped individually from three heights (0.32 m, 0.52 m, and 0.72 m). Ground reaction force was recorded to calculate the time to stabilisation. Electromyographic activities were recorded for selected lower-extremity muscles. A multivariate analysis of variance was carried out and no significant influence was found in time to stabilisation between genders or limb laterals (P > 0.05). With increasing drop height, time to stabilisation decreased significantly in two horizontal directions and the lower-extremity muscle activities were enhanced. Vertical time to stabilisation was not significantly influenced by drop height. Dynamic postural stability improved by neuromuscular change more than that required due to the increase of drop height. Double-leg landing on level ground is a stable movement, and the body would often be injured before dynamic postural stability is impaired. It is understandable to protect tissues from mechanical injuries by the sacrifice of certain dynamic postural stability in the design of protective devices or athlete training.

  16. Skeletal and body composition evaluation. Final report

    SciTech Connect

    Mazess, R.B.

    1983-03-01

    Research on radiation detectors for absorptiometry analysis of errors affecting single photon absorptiometry and development of instrumentation, analysis of errors affecting dual photon absorptiometry and development of instrumentation, comparison of skeletal measurements with other techniques, cooperation with NASA projects for skeletal evaluation in spaceflight (Experiment MO-78) and in laboratory studies with immobilized animals, studies of postmenopausal osteoporosis, organization of scientific meetings and workshops on absorptiometric measurement, and development of instrumentation for measurement of fluid shifts in the human body were performed. Instrumentation was developed that allows accurate and precise (2% error) measurements of mineral content in compact and trabecular bone and of the total skeleton. Instrumentation was also developed to measure fluid shifts in the extremities. Radiation exposure with those procedures is low (2-10 MREM). One hundred seventy three technical reports and one hundred and four published papers of studies from the University of Wisconsin Bone Mineral Lab are listed.

  17. Detection of Obstructive sleep apnea in awake subjects by exploiting body posture effects on the speech signal.

    PubMed

    Kriboy, M; Tarasiuk, A; Zigel, Y

    2014-01-01

    Obstructive sleep apnea (OSA) is a common sleep disorder. OSA is associated with several anatomical and functional abnormalities of the upper airway. It was shown that these abnormalities in the upper airway are also likely to be the reason for increased rate of apneic events in the supine position. Functional and structural changes in the vocal tract can affect the acoustic properties of speech. We hypothesize that acoustic properties of speech that are affected by body position may aid in distinguishing between OSA and non-OSA patients. We aimed to explore the possibility to differentiate OSA and non-OSA patients by analyzing the acoustic properties of their speech signal in upright sitting and supine positions. 35 awake patients were recorded while pronouncing sustained vowels in the upright sitting and supine positions. Using linear discriminant analysis (LDA) classifier, accuracy of 84.6%, sensitivity of 92.7%, and specificity of 80.0% were achieved. This study provides the proof of concept that it is possible to screen for OSA by analyzing and comparing speech properties acquired in upright sitting vs. supine positions. An acoustic-based screening system during wakefulness may address the growing needs for a reliable OSA screening tool; further studies are needed to support these findings. PMID:25570924

  18. Gravitational Effects upon Locomotion Posture

    NASA Technical Reports Server (NTRS)

    DeWitt, John K.; Bentley, Jason R.; Edwards, W. Brent; Perusek, Gail P.; Samorezov, Sergey

    2008-01-01

    Researchers use actual microgravity (AM) during parabolic flight and simulated microgravity (SM) obtained with horizontal suspension analogs to better understand the effect of gravity upon gait. In both environments, the gravitational force is replaced by an external load (EL) that returns the subject to the treadmill. However, when compared to normal gravity (N), researchers consistently find reduced ground reaction forces (GRF) and subtle kinematic differences (Schaffner et al., 2005). On the International Space Station, the EL is applied by elastic bungees attached to a waist and shoulder harness. While bungees can provide EL approaching body weight (BW), their force-length characteristics coupled with vertical oscillations of the body during gait result in a variable load. However, during locomotion in N, the EL is consistently equal to 100% body weight. Comparisons between AM and N have shown that during running, GRF are decreased in AM (Schaffner et al, 2005). Kinematic evaluations in the past have focussed on joint range of motion rather than joint posture at specific instances of the gait cycle. The reduced GRF in microgravity may be a result of differing hip, knee, and ankle positions during contact. The purpose of this investigation was to compare joint angles of the lower extremities during walking and running in AM, SM, and N. We hypothesized that in AM and SM, joints would be more flexed at heel strike (HS), mid-stance (MS) and toe-off (TO) than in N.

  19. Effects of local fatigue of the lower limbs on postural control and postural stability in standing posture.

    PubMed

    Caron, Olivier

    2003-04-10

    Postural stability and postural control were studied before and after a fatigue protocol of soleus muscles. Postural stability was assessed by the centre of gravity motion, which was computed from the motion of the centre of pressure, evaluating the postural control. Ten healthy male subjects were asked to stand as still as possible with eyes open before and after the fatigue protocol, performed in a sitting position. Fatigue was assumed on the basis of a shortening of the exertion time of the soleus muscles at 60% of their maximal voluntary contraction. Results of the whole group showed that fatigue modified postural control but did not change postural stability. The same results were observed only for some subjects. However, these results indicate an increase of the neuromuscular activity in high frequencies. PMID:12668242

  20. Determining postural stability

    NASA Technical Reports Server (NTRS)

    Lieberman, Erez (Inventor); Forth, Katharine E. (Inventor); Paloski, William H. (Inventor)

    2011-01-01

    A method for determining postural stability of a person can include acquiring a plurality of pressure data points over a period of time from at least one pressure sensor. The method can also include the step of identifying a postural state for each pressure data point to generate a plurality of postural states. The method can include the step of determining a postural state of the person at a point in time based on at least the plurality of postural states.

  1. Quantifying Postural Control during Exergaming Using Multivariate Whole-Body Movement Data: A Self-Organizing Maps Approach

    PubMed Central

    van Diest, Mike; Stegenga, Jan; Wörtche, Heinrich J.; Roerdink, Jos B. T. M; Verkerke, Gijsbertus J.; Lamoth, Claudine J. C.

    2015-01-01

    Background Exergames are becoming an increasingly popular tool for training balance ability, thereby preventing falls in older adults. Automatic, real time, assessment of the user’s balance control offers opportunities in terms of providing targeted feedback and dynamically adjusting the gameplay to the individual user, yet algorithms for quantification of balance control remain to be developed. The aim of the present study was to identify movement patterns, and variability therein, of young and older adults playing a custom-made weight-shifting (ice-skating) exergame. Methods Twenty older adults and twenty young adults played a weight-shifting exergame under five conditions of varying complexity, while multi-segmental whole-body movement data were captured using Kinect. Movement coordination patterns expressed during gameplay were identified using Self Organizing Maps (SOM), an artificial neural network, and variability in these patterns was quantified by computing Total Trajectory Variability (TTvar). Additionally a k Nearest Neighbor (kNN) classifier was trained to discriminate between young and older adults based on the SOM features. Results Results showed that TTvar was significantly higher in older adults than in young adults, when playing the exergame under complex task conditions. The kNN classifier showed a classification accuracy of 65.8%. Conclusions Older adults display more variable sway behavior than young adults, when playing the exergame under complex task conditions. The SOM features characterizing movement patterns expressed during exergaming allow for discriminating between young and older adults with limited accuracy. Our findings contribute to the development of algorithms for quantification of balance ability during home-based exergaming for balance training. PMID:26230655

  2. The dentist's operating posture - ergonomic aspects.

    PubMed

    Pîrvu, C; Pătraşcu, I; Pîrvu, D; Ionescu, C

    2014-06-15

    The practice of dentistry involves laborious high finesse dental preparations, precision and control in executions that require a particular attention, concentration and patience of the dentist and finally the dentist's physical and mental resistance. The optimal therapeutic approach and the success of practice involve special working conditions for the dentist and his team in an ergonomic environment. The meaning of the posture in ergonomics is the manner in which different parts of the body are located and thus the reports are established between them in order to allow a special task execution. This article discusses the posture adopted by dentists when they work, beginning with the balanced posture and going to different variants of posture. The ideal posture of a dentist gives him, on the one hand the optimal working conditions (access, visibility and control in the mouth) and on the other hand, physical and psychological comfort throughout the execution of the clinical acts. Although the theme of dentist posture is treated with great care and often presented in the undergraduate courses and the continuing education courses on ergonomics in dentistry, many dentists do not know the subject well enough nor the theoretical issues and therefore nor the practical applicability. The risk and perspective of the musculoskeletal disorders related to unbalanced postures should determine the dentists take postural corrective actions and compensation measures in order to limit the negative effects of working in a bad posture.

  3. “What Women Like”: Influence of Motion and Form on Esthetic Body Perception

    PubMed Central

    Cazzato, Valentina; Siega, Serena; Urgesi, Cosimo

    2012-01-01

    Several studies have shown the distinct contribution of motion and form to the esthetic evaluation of female bodies. Here, we investigated how variations of implied motion and body size interact in the esthetic evaluation of female and male bodies in a sample of young healthy women. Participants provided attractiveness, beauty, and liking ratings for the shape and posture of virtual renderings of human bodies with variable body size and implied motion. The esthetic judgments for both shape and posture of human models were influenced by body size and implied motion, with a preference for thinner and more dynamic stimuli. Implied motion, however, attenuated the impact of extreme body size on the esthetic evaluation of body postures, while body size variations did not affect the preference for more dynamic stimuli. Results show that body form and action cues interact in esthetic perception, but the final esthetic appreciation of human bodies is predicted by a mixture of perceptual and affective evaluative components. PMID:22866044

  4. "What women like": influence of motion and form on esthetic body perception.

    PubMed

    Cazzato, Valentina; Siega, Serena; Urgesi, Cosimo

    2012-01-01

    Several studies have shown the distinct contribution of motion and form to the esthetic evaluation of female bodies. Here, we investigated how variations of implied motion and body size interact in the esthetic evaluation of female and male bodies in a sample of young healthy women. Participants provided attractiveness, beauty, and liking ratings for the shape and posture of virtual renderings of human bodies with variable body size and implied motion. The esthetic judgments for both shape and posture of human models were influenced by body size and implied motion, with a preference for thinner and more dynamic stimuli. Implied motion, however, attenuated the impact of extreme body size on the esthetic evaluation of body postures, while body size variations did not affect the preference for more dynamic stimuli. Results show that body form and action cues interact in esthetic perception, but the final esthetic appreciation of human bodies is predicted by a mixture of perceptual and affective evaluative components. PMID:22866044

  5. Evaluation of a single accelerometer based biofeedback system for real-time correction of neck posture in computer users.

    PubMed

    Breen, Paul P; Nisar, Aamer; Olaighin, Gearoid

    2009-01-01

    The worldwide adoption of computers is closely linked to increased prevalence in neck and shoulder pain. Many ergonomic interventions are available; however, the lifetime prevalence of neck pain is still estimated as high as 80%. This paper introduces a biofeedback system using a novel single accelerometer placement. This system allows the user to react and correct for movement into a position of bad posture. The addition of visual information provides artificial proprioceptive information on the cranial-vertebral angle. Six subjects were tested for 5 hours with and without biofeedback. All subjects had a significant decrease in the percentage of time spent in bad posture when using biofeedback. PMID:19965101

  6. Influence of flexibility and gender on the posture of school children☆

    PubMed Central

    Coelho, Jerusa Jordão; Graciosa, Maylli Daiani; de Medeiros, Daiane Lazzeri; Pacheco, Sheila Cristina da Silva; da Costa, Leticia Miranda Resende; Ries, Lilian Gerdi Kittel

    2014-01-01

    Objective: To evaluate whether flexibility and gender influence students' posture. Method: Evaluation of 60 female and male students, aged 5 to 14 years, divided into two groups: normal flexibility (n=21) and reduced flexibility (n=39). Flexibility and posture were assessed by photogrammetry and by the elevation of the lower limbs in extension, considering the leg angle and the postural evaluation. Descriptive statistics (mean and standard deviation) were used for data analysis. Analysis of variance (ANOVA) was applied to assess the joint influence of flexibility and gender on the posture-dependent variables. After verifying an interactive effect between the variables of gender and flexibility, multiple comparisons using the t test were applied. Results: Flexibility influenced the symmetry angle of the knee (p<0.05) and anteroposterior body tilt (p<0.05). Gender did not influence postural angles (p>0.05). There was an interactive effect between the variables of gender and flexibility on the knee symmetry angle (p<0.02). Male students with reduced flexibility had greater asymmetry of the knee when compared to the other subgroups. Conclusion: Posture was influenced by an isolated effect of the variable of flexibility and by an interactive effect between gender and flexibility. PMID:25479853

  7. Obesity effect on perceived postural stress during static posture maintenance tasks.

    PubMed

    Park, Woojin; Singh, Devender P; Levy, Martin S; Jung, Eui S

    2009-09-01

    Postural stresses related to manual work tasks may be significantly affected by the bodily condition of workers. One such condition is obesity, which is characterised by excess fat mass in the body. This study empirically examined the obesity effect on postural stress during static posture maintenance tasks. In total, 20 obese and 20 non-obese participants performed static box-holding for a set of 84 working postures defined based on the Ovako Working Posture Analysing System. The participants reported postural stresses using the rated perceived exertion scale. Obesity was found to significantly increase postural stress across the 84 working postures and, also, amplify the effects of postural changes on postural stress. The study findings suggest that ergonomic workplace/job design for obese workers would be a challenge requiring a proactive approach and creativity in problem solving. In addition, the use of ergonomic knowledge in design would be more critical when targeting obese than non-obese workers. The study findings are relevant to ergonomic workplace/job design for obese workers.

  8. Take a stand on your decisions, or take a sit: posture does not affect risk preferences in an economic task.

    PubMed

    O'Brien, Megan K; Ahmed, Alaa A

    2014-01-01

    Physiological and emotional states can affect our decision-making processes, even when these states are seemingly insignificant to the decision at hand. We examined whether posture and postural threat affect decisions in a non-related economic domain. Healthy young adults made a series of choices between economic lotteries in various conditions, including changes in body posture (sitting vs. standing) and changes in elevation (ground level vs. atop a 0.8-meter-high platform). We compared three metrics between conditions to assess changes in risk-sensitivity: frequency of risky choices, and parameter fits of both utility and probability weighting parameters using cumulative prospect theory. We also measured skin conductance level to evaluate physiological response to the postural threat. Our results demonstrate that body posture does not significantly affect decision making. Secondly, despite increased skin conductance level, economic risk-sensitivity was unaffected by increased threat. Our findings indicate that economic choices are fairly robust to the physiological and emotional changes that result from posture or postural threat. PMID:25083345

  9. Take a stand on your decisions, or take a sit: posture does not affect risk preferences in an economic task

    PubMed Central

    O’Brien, Megan K.

    2014-01-01

    Physiological and emotional states can affect our decision-making processes, even when these states are seemingly insignificant to the decision at hand. We examined whether posture and postural threat affect decisions in a non-related economic domain. Healthy young adults made a series of choices between economic lotteries in various conditions, including changes in body posture (sitting vs. standing) and changes in elevation (ground level vs. atop a 0.8-meter-high platform). We compared three metrics between conditions to assess changes in risk-sensitivity: frequency of risky choices, and parameter fits of both utility and probability weighting parameters using cumulative prospect theory. We also measured skin conductance level to evaluate physiological response to the postural threat. Our results demonstrate that body posture does not significantly affect decision making. Secondly, despite increased skin conductance level, economic risk-sensitivity was unaffected by increased threat. Our findings indicate that economic choices are fairly robust to the physiological and emotional changes that result from posture or postural threat. PMID:25083345

  10. Is there interaction between vision and local fatigue of the lower limbs on postural control and postural stability in human posture?

    PubMed

    Caron, Olivier

    2004-06-01

    An investigation of the interaction between local fatigue and vision on postural control and postural stability was carried out. Fatigue was effected in a sitting position and was assumed based on a shortening of the exertion time of the soleus muscles (60% of their maximal voluntary contractions). Postural stability was assessed by centre of gravity motion, which was computed from centre of pressure motion, evaluating postural control. Ten healthy male subjects were asked to stand as still as possible with eyes open (EO) and eyes closed (EC) before and after the fatigue protocol. Results showed that fatigue produced similar effects for the two vision conditions on postural control and postural stability analyzed separately, increasing postural control and leaving postural stability unchanged. Local fatigue essentially produced an increase of neuromuscular activity in high frequencies. However, this increase was more pronounced for the EO, as compared to the EC condition. PMID:15157987

  11. Specificity of Postural Sway to the Demands of a Precision Task at Sea

    ERIC Educational Resources Information Center

    Chen, Fu-Chen; Stoffregen, Thomas A.

    2012-01-01

    Mariners actively adjust their body orientation in response to ship motion. On a ship at sea, we evaluated relations between standing postural activity and the performance of a precision aiming task. Standing participants (experienced mariners) maintained the beam from a handheld laser on a target. Targets were large or small, thereby varying the…

  12. Risk factors associated with structural postural changes in the spinal column of children and adolescents

    PubMed Central

    Sedrez, Juliana Adami; da Rosa, Maria Izabel Zaniratti; Noll, Matias; Medeiros, Fernanda da Silva; Candotti, Claudia Tarragô

    2015-01-01

    OBJECTIVE: To investigate the association between behavioral risk factors, specifically postural habits, with the presence of structural changes in the spinal column of children and adolescents. METHODS: 59 students were evaluated through the self-reporting Back Pain and Body Posture Evaluation Instrument and spinal panoramic radiographic examination. Spine curvatures were classified based on Cobb angles, as normal or altered in the saggital plane and as normal or scoliotic in the frontal plane. Data were analyzed using SPSS 18.0, based on descriptive statistics and chi-square association test (a=0,05). RESULTS: The prevalence of postural changes was 79.7% (n=47), of which 47.5% (n=28) showed frontal plane changes and 61% (n=36) sagital plane changes. Significant association was found between the presence of thoracic kyphosis and female gender, practice of physical exercises only once or twice a week, sleep time greater than 10 hours, inadequate postures when sitting on a seat and sitting down to write, and how school supplies are carried. Lumbar lordosis was associated with the inadequate way of carrying the school backpack (asymmetric); and scoliosis was associated wuth the practice of competitive sports and sleep time greater than 10 hours. CONCLUSIONS: Lifestyle may be associated with postural changes. It is important to develop health policies in order to reduce the prevalence of postural changes, by decreasing the associated risk factors. PMID:25623725

  13. Obesity, mechanical and strength relationships to postural control in adolescence.

    PubMed

    King, Adam C; Challis, John H; Bartok, Cynthia; Costigan, F Aileen; Newell, Karl M

    2012-02-01

    There is preliminary evidence that BMI is positively correlated with movement variability of standing posture. However, this negative effect of obesity on postural control may be mediated by the change in other body scale variables (e.g., mechanical and fitness) that also occur with changes in BMI. This study investigated the influence of selected body scale (height, body mass, BMI), body composition (body fat percentage), mechanical (moment of inertia - MI) and strength (S) variables as predictors of the control of postural motion in adolescents. 125 healthy adolescents (65 boys, 60 girls) with a wide range of BMI (13.8-31.0 kg/m(2)) performed a battery of tests that assessed body composition, anthropometry, muscular strength and postural control. Multiple measures of postural motion variability were derived for analysis with body scale, mechanical and lower extremity strength variables separately for boys and girls. BMI, height and body mass, considered both separately and collectively, were poor and/or inconsistent predictors of variability in all three posture tasks. However, the ratio of lower extremity strength to whole body moment of inertia showed the highest positive correlation to most postural variability measures in both boys and girls and these effects were strongest in the less stable tasks of single leg standing and recovery of stance. Our findings support the hypothesis that diminished lower extremity strength to mechanical constraint ratio compromises the robustness of the strength to body scale relation in movement and postural control. PMID:22018701

  14. Working postures of dentists and dental hygienists.

    PubMed

    Marklin, Richard W; Cherney, Kevin

    2005-02-01

    A joint study was conducted by a manufacturer of dental stools in the Midwest of the United States and Marquette University to measure the occupational postures of dentists and dental hygienists. The postures of 10 dentists and 10 dental hygienists were assessed using work sampling and video techniques. Postural data of the neck, shoulders and lower back were recorded from video and categorized into 30-degree intervals: o (neutral posture of respective joint), 30, 60 and 90 degrees. Each subject's postures were observed while they were treating patients during a four-hour period, during which 100 observations of postures were recorded at random times. Compared to standing, dentists and dental hygienists were seated 78 percent and 66 percent of the time, respectively. Dentists and dental hygienists flexed their trunk at least 30 degrees more than 50 percent of the time. They flexed their neck at least 30 degrees 85 percent of the time during the four-hour duration, and their shoulders were elevated to the side of their trunk (abducted) at least 30 degrees more half of the time. The postures of the trunk, shoulders, and neck were primarily static. This database of postures can be used by dental professionals and ergonomists to assess the risk dentists and dental hygienists are exposed to musculoskeletal disorders, such as low back pain or shoulder tenosynovitis, from deviated joint postures. They could use these data to select dental furniture or dental devices that promote good body posture, i.e., reduce the magnitude and duration of deviated joint postures, which, in theory, would decrease the risk of musculoskeletal disorders.

  15. Relation between the Sensory and Anthropometric Variables in the Quiet Standing Postural Control: Is the Inverted Pendulum Important for the Static Balance Control?

    PubMed Central

    Alonso, Angélica C.; Mochizuki, Luis; Silva Luna, Natália Mariana; Ayama, Sérgio; Canonica, Alexandra Carolina; Greve, Júlia M. D. A.

    2015-01-01

    The aim of this study was to evaluate the relation between the sensory and anthropometric variables in the quiet standing. Methods. One hundred individuals (50 men, 50 women; 20–40 years old) participated in this study. For all participants, the body composition (fat tissue, lean mass, bone mineral content, and bone mineral density) and body mass, height, trunk-head length, lower limb length, and upper limb length were measured. The center of pressure was measured during the quiet standing posture, the eyes opened and closed with a force platform. Correlation and regression analysis were run to analyze the relation among body composition, anthropometric data, and postural sway. Results. The correlation analysis showed low relation between postural sway and anthropometric variables. The multiple linear regression analyses showed that the height explained 12% of the mediolateral displacement and 11% of the center of pressure area. The length of the trunk head explained 6% of displacement in the anteroposterior postural sway. During eyes closed condition, the support basis and height explained 18% of mediolateral postural sway. Conclusion. The postural control depends on body composition and dimension. This relation is mediated by the sensory information. The height was the anthropometric variable that most influenced the postural sway. PMID:26539550

  16. Balance and knee extensibility evaluation of hemiplegic gait using an inertial body sensor network

    PubMed Central

    2013-01-01

    Background Most hemiplegic patients have difficulties in their balance and posture control while walking because of the asymmetrical posture and the abnormal body balance. The assessment of rehabilitation of hemiplegic gait is usually made by doctors using clinical scale, but it is difficult and could not be used frequently. It is therefore needed to quantitatively analyze the characteristics of hemiplegic gait. Thus the assessment would be simple, and real-time evaluation of rehabilitation could be carried out. Methods Twenty subjects (ten hemiplegic patients, ten normal subjects) were recruited. The subjects walked straight for five meters at their self-selected comfortable speed towards a target line on the floor. Xsens MTx motion trackers were used for acquiring gestures of body segments to estimate knee joint angles and identify gait cycles. A practical method for data acquisition that does not need to obtain accurate distances between a knee joint and its corresponding sensors is presented. Results The results showed that there were significant differences between the two groups in the three nominated angle amplitudes. The mean values of balance level of each parameter in hemiplegic gait and normal gait were: 0.21 versus 0.01, 0.18 versus 0.03, and 0.92 versus 0.03, respectively. The mean values of added angles of each parameter in hemiplegic gait and normal gait were: 74.64 versus 91.31, -76.48 versus −132.4, and 6.77 versus 35.74. Conclusions It was concluded that the wearable bio-motion acquisition platform provided a practical approach that was effective in discriminating gait symptoms between hemiplegic and asymptomatic subjects. The extensibility of hemiplegic patients’ lower limbs was significantly lower than that of normal subjects, and the hemiplegic gait had worse balance level compared with normal gait. The effect of rehabilitation training of hemiplegic gait could be quantitatively analyzed. PMID:23988116

  17. Vicarious perception of postural discomfort and exertion.

    PubMed

    Drury, Colin G; Atiles, Moises; Chaitanya, Mohan; Lin, Jui-Feng; Marin, Clara; Nasarwanji, Mahiyar; Paluszak, Doug; Russell, Casey; Stone, Richard; Sunm, Michelle

    2006-11-15

    Perceived exertion and discomfort have been used extensively in ergonomics practice. Job incumbents typically rate their exertion on scales such as Borg's rated perceived effort (RPE) and their discomfort on scales such as Corlett and Bishop's body part discomfort scales (BPD). This study asks whether exertion and discomfort can be perceived by an external observer, i.e. is vicarious perception possible? Four participants (targets) performed 20 postural holding tasks selected from Ovako Working Posture Analysing System postures and gave RPE and BPD scores for each posture. Video clips of each target in each posture were shown to four expert ergonomists and 23 novices, who also gave RPE and BPD scores. Correlations between targets and observers scores were high, with significance exceeding p = 0.01. Observers were generally conservative, rating easy postures too high and difficult postures too low. All observers rated female targets higher than male targets. Female observers rated all targets higher then male observers. Vicarious perception of discomfort and exertion was possible, but there was not a one-to-one correspondence to ratings given by those experiencing the posture.

  18. Exercise and Posture

    MedlinePlus

    ... Info For Teens Message Boards & Forums Donate Shop Exercise & Posture About Spondylitis / Exercise & Posture Overview For The ... Diet Blood Work and Spondylitis Spondylitis Awareness Month Exercise Exercise is an integral part of any spondylitis ...

  19. BodyWise: evaluating a pilot body image group for patients with anorexia nervosa.

    PubMed

    Mountford, Victoria A; Brown, Amy; Bamford, Bryony; Saeidi, Saeideh; Morgan, John F; Lacey, Hubert

    2015-01-01

    Body image disturbance can be enduring and distressing to individuals with eating disorders and effective treatments remain limited. This pilot study evaluated a group-based treatment-BodyWise-developed for use in full and partial hospitalization with patients with anorexia nervosa at low weight. A partial crossover waitlist design was used. BodyWise (N = 50) versus treatment as usual (N = 40) were compared on standardized measures of body image disturbance. Results demonstrated significant improvement in the group compared to treatment as usual for the primary outcome measure (Eating Disorder Examination-Questionnaire Shape Concern subscale) and other manifestations of body image disturbance including body checking and body image quality of life. BodyWise appeared acceptable to participants, and was easy to deliver within the pragmatics of a busy eating disorder service. There is potential for its wider dissemination as a precursor to more active body image interventions.

  20. Exemplification of Movement Patterns and Their Influence on Body Posture in Younger School-Age Children on the Basis of an Authorial Program “I Take Care of My Spine”

    PubMed Central

    Brzek, Anna; Plinta, Ryszard

    2016-01-01

    Abstract Exemplification of movement patterns is most noticeable in the youngest pupils group. Generally, children do not know which patterns are correct and which ones are risk factors. After correcting and stabilizing some improper patterns, a child can perform their daily activities without constant cognizance of their appropriateness. The concept of this research is included in a paradigm for the quality research conducted as action-research, which assumed a quality and efficiency improvement of health education in Polish schools. The main aim of this study was to encourage pupils, their parents and teachers to perform pro-health behaviors oriented toward maintaining an appropriate body posture. First, the study aimed to assess the postures of children involved in the authorial program “I take care of my spine” in comparison with a group of children without diagnosed postural defects and not involved in the curriculum. The examinations covered a group of 144 children (group A) ages 7 to 9 years (mean 7.60 ± 0.64 years) with appropriate body postures recognized in the screening test, which was conducted at a school where the curriculum “I take care of my spine” was launched. The control group included 222 healthy children at a similar age who attended schools where the curriculum was not implemented. The examinations were performed 2 times, as follows: the first time occurred before the program “I take care of my spine” was launched (initial examination), and the second time after 9 to 10 months of full participation in the program's activities and after 1 year of observation of children from group B (final examination). A significant improvement of posturometric parameters in the main group and worsening of the parameters in the control group were noted. The results in examined groups of children and diversification of the results were linked to implementing the prevention program in the main group. In the group of children involved in the

  1. Exemplification of Movement Patterns and Their Influence on Body Posture in Younger School-Age Children on the Basis of an Authorial Program "I Take Care of My Spine".

    PubMed

    Brzek, Anna; Plinta, Ryszard

    2016-03-01

    Exemplification of movement patterns is most noticeable in the youngest pupils group. Generally, children do not know which patterns are correct and which ones are risk factors. After correcting and stabilizing some improper patterns, a child can perform their daily activities without constant cognizance of their appropriateness. The concept of this research is included in a paradigm for the quality research conducted as action-research, which assumed a quality and efficiency improvement of health education in Polish schools.The main aim of this study was to encourage pupils, their parents and teachers to perform pro-health behaviors oriented toward maintaining an appropriate body posture. First, the study aimed to assess the postures of children involved in the authorial program "I take care of my spine" in comparison with a group of children without diagnosed postural defects and not involved in the curriculum.The examinations covered a group of 144 children (group A) ages 7 to 9 years (mean 7.60 ± 0.64 years) with appropriate body postures recognized in the screening test, which was conducted at a school where the curriculum "I take care of my spine" was launched. The control group included 222 healthy children at a similar age who attended schools where the curriculum was not implemented. The examinations were performed 2 times, as follows: the first time occurred before the program "I take care of my spine" was launched (initial examination), and the second time after 9 to 10 months of full participation in the program's activities and after 1 year of observation of children from group B (final examination).A significant improvement of posturometric parameters in the main group and worsening of the parameters in the control group were noted. The results in examined groups of children and diversification of the results were linked to implementing the prevention program in the main group. In the group of children involved in the postural prevention program

  2. Postural stability in children with hemiplegia estimated for three postural conditions: standing, sitting and kneeling.

    PubMed

    Szopa, Andrzej; Domagalska-Szopa, Małgorzata

    2015-04-01

    Postural control deficit is one of the most important problems in children with cerebral palsy (CP). The purpose of the presented study was to compare the effects of body posture asymmetry alone (i.e., in children with mild scoliosis) with the effects of body posture impairment (i.e., in children with hemiplegia) on postural stability. Forty-five outpatients with hemiplegia and 51 children with mild scoliosis were assessed using a posturography device. The examination comprised two parts: (1) analysis of the static load distribution; and (2) a posturographic test (CoP measurements) conducted in three postural conditions: standing, sitting and kneeling. Based on the asymmetry index of the unaffected/affected body sides while standing, the children with hemiplegia were divided into two different postural patterns: a pro-gravitational postural pattern (PGPP) and an anti-gravitational postural pattern (AGPP) (Domagalska-Szopa & Szopa (2013). BioMed Research International, 2013, 462094; (2014). Therapeutics and Clinical Risk Management, 10, 113). The group of children with mild scoliosis, considered as a standard for static body weight distribution, was used as the reference group. The results of present study only partially confirmed that children with hemiplegia have increased postural instability. Strong weight distribution asymmetry was found in children with an AGPP, which induced larger lateral-medial CoP displacements compared with children with scoliosis. In children with hemiplegia, distinguishing between their postural patterns may be useful to improve the guidelines for early therapy children with an AGPP before abnormal patterns of weight-bearing asymmetry are fully established. PMID:25677032

  3. Effect of visual stimulus using central and peripheral visual field on postural control of normal subjects.

    PubMed

    Park, Du-Jin

    2016-06-01

    [Purpose] This study investigated the effects of visual stimulus using central and peripheral vision fields on postural control. [Subjects and Methods] The subjects consisted of 40 young adult volunteers (15 males, 25 females) who had been informed of the study purpose and procedure. The subjects were randomly divided into four groups of differing visual stimulus. Each group was given visual intervention in a standing position for 3 minutes. Postural control was evaluated before and after visual intervention. [Results] The results of the functional reach test and body sway test showed significant differences among the four groups. [Conclusion] The two-way peripheral vision-field group showed significantly more body sway after visual intervention than the other three groups. This finding may suggest two-way peripheral vision field is a more effective visual stimulus for training postural control and balance.

  4. Effect of visual stimulus using central and peripheral visual field on postural control of normal subjects

    PubMed Central

    Park, Du-Jin

    2016-01-01

    [Purpose] This study investigated the effects of visual stimulus using central and peripheral vision fields on postural control. [Subjects and Methods] The subjects consisted of 40 young adult volunteers (15 males, 25 females) who had been informed of the study purpose and procedure. The subjects were randomly divided into four groups of differing visual stimulus. Each group was given visual intervention in a standing position for 3 minutes. Postural control was evaluated before and after visual intervention. [Results] The results of the functional reach test and body sway test showed significant differences among the four groups. [Conclusion] The two-way peripheral vision-field group showed significantly more body sway after visual intervention than the other three groups. This finding may suggest two-way peripheral vision field is a more effective visual stimulus for training postural control and balance. PMID:27390412

  5. An OWAS-based analysis of nurses' working postures.

    PubMed

    Engels, J A; Landeweerd, J A; Kant, Y

    1994-05-01

    The working postures of Dutch nurses (n = 18) in an orthopaedic ward and a urology ward were observed using the Ovako Working posture Analysis System (OWAS). During observation, both working postures and activities were recorded. A specially developed computer program was used for data analysis. By means of this program, it was possible to calculate the working posture load for each activity and the contribution of a specific activity to the total working posture load. This study shows that some activities of the nurses in both wards were performed with poor working postures. In the orthopaedic (resp. urology) ward two (resp. one) out of 19 observed postures of parts of the body were classified as Action Category 2. Moreover, 20% (resp. 16%) of the so-called typical working postures was classified in Action Category 2. This suggests, that in both wards working postures that are slightly harmful to the musculoskeletal system, occur during a substantial part of the working day. Differences between both wards with respect to working posture load and time expenditure were determined. Activities causing the workload to fall into OWAS higher Action Categories were identified. The data show that poor working postures in the nursing profession not only occur during patient handling activities but also during tasks like 'administration'. Focusing on patient-handling (i.e., lifting patients) in order to determine the load on the musculoskeletal system would therefore lead to an underestimation of the total working posture load of nurses.

  6. Posture and balance control in patients with acromegaly: results of a cross-sectional study.

    PubMed

    Lopes, Agnaldo José; da Silva, Débora Pedroza Guedes; Kasuki, Leandro; Gadelha, Mônica Roberto; Camilo, Gustavo Bittencourt; Guimarães, Fernando Silva

    2014-01-01

    Acromegaly is a chronic debilitating disease that presents with multiple systemic manifestations, including changes in body composition, joint abnormalities, muscular impairment and visual disturbances. This study aimed to assess posture and body balance in acromegalic patients and to establish the correlation between these measures. Twenty-eight acromegalic patients and a similar number of control subjects matched for sex, age, weight, height and body mass index underwent postural evaluation using the photogrammetry and measurement of balance using the stabilometry in two tasks: feet apart, eyes open and feet together, eyes closed. In comparison with the control group, the acromegalic group presented postural deviations in lateral views in the vertical alignment of the trunk (P=0.001 for the right side and P=0.021 for the left), the hip angle (P=0001 for the right side and P=0.016 for the left side) and horizontal alignment of the pelvis (P=0.017 for the right and P<0.001 for the left side). Compared with healthy subjects, the acromegalic patients presented displacement of the centre of pressure in both the anterior-posterior direction and the medial-lateral direction in both evaluated tasks. We observed significant correlations between balance measures and the following posture evaluation variables: distance between the lower limbs, horizontal alignment of the head and vertical alignment of the head. Our results suggest that posture and balance need to be evaluated for acromegalic patients in clinical practice, as there are significant postural imbalances and deviations in these patients. PMID:24708904

  7. Radiologic Assessment of Forward Head Posture and Its Relation to Myofascial Pain Syndrome

    PubMed Central

    Sun, An; Yeo, Han Gyeol; Kim, Tae Uk; Hyun, Jung Keun

    2014-01-01

    Objective To assess head posture using cervical spine X-rays to find out whether forward head posture is related to myofascial pain syndrome (MPS) in neck and shoulder. Methods Eighty-eight participants who were diagnosed with MPS in neck and shoulder were evaluated in this study. Four parameters (distance among head, cervical spines, and shoulder, and cervical angle) were measured from lateral view of cervical spine X-ray. The location and number of trigger points in the neck and shoulder and symptom duration were evaluated for each patient. Results Both horizontal distances between C1 vertebral body and C7 spinous process and between the earhole and C7 vertebral body were negatively correlated with cervical angle reflecting cervical lordosis (p<0.05). Younger patients had significantly (p<0.05) less cervical angle with more forward head posture. There was no relationship between MPS (presence, location, and number of trigger points) and radiologic assessments (distance parameters and the cervical angle). Conclusion Forward head posture and reduced cervical lordosis were seen more in younger patients with spontaneous neck pain. However, these abnormalities did not correlate with the location or the number of MPS. Further studies are needed to delineate the mechanism of neck pain in patients with forward head posture. PMID:25566482

  8. The effects of wind and posture on the aerodynamic performance during the flight stage of skiing.

    PubMed

    Chen, Zhifeng; Fang, Haisheng

    2011-09-01

    Numerical simulation is conducted to evaluate the wind and posture effects on the aerodynamic performance of a skier during the flight stage. Both steady and unsteady models are applied on a 2D geometry. Using the Fluent code, the fundamental equations of fluid flow are solved simultaneously. In particular we focus on the influence of wind speed and direction on aerodynamic forces with several different postures of the skier in steady modeling. For a chosen case, the unsteady models are used to predict the transient characteristics of streamline distributions and aerodynamic forces. It is found that the skier's postures, wind speed, and direction play a significant role. The wind condition affects the pressure force (the form drag) on the skier and makes it a resistance or thrust regarding wind directions. The optimized posture with a minimization of resistance under a facing wind is determined as a moving-forward body of the skier. The unsteady modeling reveals that the wake around the skier and aerodynamic forces are strongly dependent on time. This initial study not only provides a qualitative and theoretical basis for the athletes to understand the effects of wind and postures, and then to optimize their postures according to the wind condition during the flight stage of skiing, but also builds the foundation for the systematic study of skiing process with more advanced CFD models in the future.

  9. The effects of wind and posture on the aerodynamic performance during the flight stage of skiing.

    PubMed

    Chen, Zhifeng; Fang, Haisheng

    2011-09-01

    Numerical simulation is conducted to evaluate the wind and posture effects on the aerodynamic performance of a skier during the flight stage. Both steady and unsteady models are applied on a 2D geometry. Using the Fluent code, the fundamental equations of fluid flow are solved simultaneously. In particular we focus on the influence of wind speed and direction on aerodynamic forces with several different postures of the skier in steady modeling. For a chosen case, the unsteady models are used to predict the transient characteristics of streamline distributions and aerodynamic forces. It is found that the skier's postures, wind speed, and direction play a significant role. The wind condition affects the pressure force (the form drag) on the skier and makes it a resistance or thrust regarding wind directions. The optimized posture with a minimization of resistance under a facing wind is determined as a moving-forward body of the skier. The unsteady modeling reveals that the wake around the skier and aerodynamic forces are strongly dependent on time. This initial study not only provides a qualitative and theoretical basis for the athletes to understand the effects of wind and postures, and then to optimize their postures according to the wind condition during the flight stage of skiing, but also builds the foundation for the systematic study of skiing process with more advanced CFD models in the future. PMID:22010736

  10. Evaluation of a 433 MHz Band Body Sensor Network for Biomedical Applications

    PubMed Central

    Kim, Saim; Brendle, Christian; Lee, Hyun-Young; Walter, Marian; Gloeggler, Sigrid; Krueger, Stefan; Leonhardt, Steffen

    2013-01-01

    Body sensor networks (BSN) are an important research topic due to various advantages over conventional measurement equipment. One main advantage is the feasibility to deploy a BSN system for 24/7 health monitoring applications. The requirements for such an application are miniaturization of the network nodes and the use of wireless data transmission technologies to ensure wearability and ease of use. Therefore, the reliability of such a system depends on the quality of the wireless data transmission. At present, most BSNs use ZigBee or other IEEE 802.15.4 based transmission technologies. Here, we evaluated the performance of a wireless transmission system of a novel BSN for biomedical applications in the 433 MHz ISM band, called Integrated Posture and Activity NEtwork by Medit Aachen (IPANEMA) BSN. The 433 MHz ISM band is used mostly by implanted sensors and thus allows easy integration of such into the BSN. Multiple measurement scenarios have been assessed, including varying antenna orientations, transmission distances and the number of network participants. The mean packet loss rate (PLR) was 0.63% for a single slave, which is comparable to IEEE 802.15.4 BSNs in the proximity of Bluetooth or WiFi networks. Secondly, an enhanced version is evaluated during on-body measurements with five slaves. The mean PLR results show a comparable good performance for measurements on a treadmill (2.5%), an outdoor track (3.4%) and in a climate chamber (1.5%). PMID:23344383

  11. Evaluation of a 433 MHz band body sensor network for biomedical applications.

    PubMed

    Kim, Saim; Brendle, Christian; Lee, Hyun-Young; Walter, Marian; Gloeggler, Sigrid; Krueger, Stefan; Leonhardt, Steffen

    2013-01-01

    Body sensor networks (BSN) are an important research topic due to various advantages over conventional measurement equipment. One main advantage is the feasibility to deploy a BSN system for 24/7 health monitoring applications. The requirements for such an application are miniaturization of the network nodes and the use of wireless data transmission technologies to ensure wearability and ease of use. Therefore, the reliability of such a system depends on the quality of the wireless data transmission. At present, most BSNs use ZigBee or other IEEE 802.15.4 based transmission technologies. Here, we evaluated the performance of a wireless transmission system of a novel BSN for biomedical applications in the 433MHz ISM band, called Integrated Posture and Activity NEtwork by Medit Aachen (IPANEMA) BSN. The 433MHz ISM band is used mostly by implanted sensors and thus allows easy integration of such into the BSN. Multiple measurement scenarios have been assessed, including varying antenna orientations, transmission distances and the number of network participants. The mean packet loss rate (PLR) was 0.63% for a single slave, which is comparable to IEEE 802.15.4 BSNs in the proximity of Bluetooth or WiFi networks. Secondly, an enhanced version is evaluated during on-body measurements with five slaves. The mean PLR results show a comparable good performance for measurements on a treadmill (2.5%), an outdoor track (3.4%) and in a climate chamber (1.5%). PMID:23344383

  12. An Evaluation of Upper and Lower Pharyngeal Airway Width, Tongue Posture and Hyoid Bone Position in Subjects with Different Growth Patterns

    PubMed Central

    Tarkar, Jaipal Singh; Parashar, Sandeep; Gupta, Garima; Bhardwaj, Preeti; Singh, Atul; Singh, Parul

    2016-01-01

    Introduction It is important to evaluate the position of the hyoid bone in relation to the tongue at the beginning of orthodontic treatment so that during the treatment, its position may be directed hence overall impact on airway could be assessed. Aim The aim of this study was to evaluate the upper and lower pharyngeal airway dimensions, posture of tongue and hyoid bone position in young adults with different growth patterns. Materials and Methods Sample size of the study included 90 post-adolescent subjects, within the age range of 18-32 years. Based on the different growth pattern of the face, subjects were divided into Group I (n=30; average growth pattern), Group II (n=30; horizontal growth pattern) and Group III (n=30; vertical growth pattern). Lateral cephalogram were traced and analysed manually by the same investigator for evaluation of upper and lower pharyngeal airway, tongue posture and hyoid bone position. The intergroup comparison of upper and lower pharyngeal airway dimensions, posture of tongue and hyoid bone was performed with one-way ANOVA test. Results The results showed that upper oropharyngeal widths were significantly different in different facial skeletal patterns (p=0.00). Subjects with vertical skeletal pattern have significantly narrower upper airways than those with horizontal skeletal pattern (p= 0.025). There was significantly higher difference in position of dorsum of the tongue in vertical growth pattern group (p=0.00). The hyoid bone was positioned farther from the mandibular symphysis in brachyfacial subjects, reflected by the larger H-RGN (Hyoid- retrognathion) values compared with the dolichofacial and normal subjects (p=0.044). Conclusion The upper oropharyngeal width was found to be narrower in subjects with vertical growth pattern. The dorsum of the tongue is seen to be placed higher in subjects with vertical growth pattern. The hyoid bone was more inferiorly and posteriorly positioned in subjects with horizontal growth pattern

  13. Methods of Postural Assessment Used for Sports Persons

    PubMed Central

    Singla, Deepika

    2014-01-01

    Occurrence of postural defects has become very common now-a-days not only in general population but also in sports persons. There are various methods which can be used to assess these postural defects. These methods have evolved over a period of many years. This paper is first of its kind to summarize the methods of postural assessment which have been used and which can be used for evaluation of postural abnormalities in sports persons such as the visual observation, plumbline, goniometry, photographic, radiographic, photogrammetric, flexiruler, electromagnetic tracking device etc. We recommend more and more postural evaluation studies to be done in future based on the photogrammetric method. PMID:24959470

  14. Transfer of Dynamic Learning Across Postures

    PubMed Central

    Wolpert, Daniel M.

    2009-01-01

    When learning a difficult motor task, we often decompose the task so that the control of individual body segments is practiced in isolation. But on re-composition, the combined movements can result in novel and possibly complex internal forces between the body segments that were not experienced (or did not need to be compensated for) during isolated practice. Here we investigate whether dynamics learned in isolation by one part of the body can be used by other parts of the body to immediately predict and compensate for novel forces between body segments. Subjects reached to targets while holding the handle of a robotic, force-generating manipulandum. One group of subjects was initially exposed to the novel robot dynamics while seated and was then tested in a standing position. A second group was tested in the reverse order: standing then sitting. Both groups adapted their arm dynamics to the novel environment, and this movement learning transferred between seated and standing postures and vice versa. Both groups also generated anticipatory postural adjustments when standing and exposed to the force field for several trials. In the group that had learned the dynamics while seated, the appropriate postural adjustments were observed on the very first reach on standing. These results suggest that the CNS can immediately anticipate the effect of learned movement dynamics on a novel whole-body posture. The results support the existence of separate mappings for posture and movement, which encode similar dynamics but can be adapted independently. PMID:19710374

  15. Static and dynamic posture control in postlingual cochlear implanted patients: effects of dual-tasking, visual and auditory inputs suppression

    PubMed Central

    Bernard-Demanze, Laurence; Léonard, Jacques; Dumitrescu, Michel; Meller, Renaud; Magnan, Jacques; Lacour, Michel

    2014-01-01

    Posture control is based on central integration of multisensory inputs, and on internal representation of body orientation in space. This multisensory feedback regulates posture control and continuously updates the internal model of body's position which in turn forwards motor commands adapted to the environmental context and constraints. The peripheral localization of the vestibular system, close to the cochlea, makes vestibular damage possible following cochlear implant (CI) surgery. Impaired vestibular function in CI patients, if any, may have a strong impact on posture stability. The simple postural task of quiet standing is generally paired with cognitive activity in most day life conditions, leading therefore to competition for attentional resources in dual-tasking, and increased risk of fall particularly in patients with impaired vestibular function. This study was aimed at evaluating the effects of postlingual cochlear implantation on posture control in adult deaf patients. Possible impairment of vestibular function was assessed by comparing the postural performance of patients to that of age-matched healthy subjects during a simple postural task performed in static (stable platform) and dynamic (platform in translation) conditions, and during dual-tasking with a visual or auditory memory task. Postural tests were done in eyes open (EO) and eyes closed (EC) conditions, with the CI activated (ON) or not (OFF). Results showed that the postural performance of the CI patients strongly differed from the controls, mainly in the EC condition. The CI patients showed significantly reduced limits of stability and increased postural instability in static conditions. In dynamic conditions, they spent considerably more energy to maintain equilibrium, and their head was stabilized neither in space nor on trunk: they behaved dynamically without vision like an inverted pendulum while the controls showed a whole body rigidification strategy. Hearing (prosthesis on) as well

  16. Static and dynamic posture control in postlingual cochlear implanted patients: effects of dual-tasking, visual and auditory inputs suppression.

    PubMed

    Bernard-Demanze, Laurence; Léonard, Jacques; Dumitrescu, Michel; Meller, Renaud; Magnan, Jacques; Lacour, Michel

    2013-01-01

    Posture control is based on central integration of multisensory inputs, and on internal representation of body orientation in space. This multisensory feedback regulates posture control and continuously updates the internal model of body's position which in turn forwards motor commands adapted to the environmental context and constraints. The peripheral localization of the vestibular system, close to the cochlea, makes vestibular damage possible following cochlear implant (CI) surgery. Impaired vestibular function in CI patients, if any, may have a strong impact on posture stability. The simple postural task of quiet standing is generally paired with cognitive activity in most day life conditions, leading therefore to competition for attentional resources in dual-tasking, and increased risk of fall particularly in patients with impaired vestibular function. This study was aimed at evaluating the effects of postlingual cochlear implantation on posture control in adult deaf patients. Possible impairment of vestibular function was assessed by comparing the postural performance of patients to that of age-matched healthy subjects during a simple postural task performed in static (stable platform) and dynamic (platform in translation) conditions, and during dual-tasking with a visual or auditory memory task. Postural tests were done in eyes open (EO) and eyes closed (EC) conditions, with the CI activated (ON) or not (OFF). Results showed that the postural performance of the CI patients strongly differed from the controls, mainly in the EC condition. The CI patients showed significantly reduced limits of stability and increased postural instability in static conditions. In dynamic conditions, they spent considerably more energy to maintain equilibrium, and their head was stabilized neither in space nor on trunk: they behaved dynamically without vision like an inverted pendulum while the controls showed a whole body rigidification strategy. Hearing (prosthesis on) as well

  17. Postural sway and perceived comfort in pointing tasks.

    PubMed

    Solnik, Stanislaw; Pazin, Nemanja; Coelho, Chase J; Rosenbaum, David A; Zatsiorsky, Vladimir M; Latash, Mark L

    2014-05-21

    In this study, we explored relations between indices of postural sway and perceived comfort during pointing postures performed by standing participants. The participants stood on a force plate, grasped a pointer with the dominant (right) hand, and pointed to targets located at four positions and at two distances from the body. We quantified postural sway over 60-s intervals at each pointing posture, and found no effects of target location or distance on postural sway indices. In contrast, comfort ratings correlated significantly with indices of one of the sway components, trembling. Our observations support the hypothesis that rambling and trembling sway components involve different neurophysiological mechanisms. They also suggest that subjective perception of comfort may be more important than the actual posture for postural sway. PMID:24686189

  18. Postural sway and perceived comfort in pointing tasks

    PubMed Central

    Solnik, Stanislaw; Pazin, Nemanja; Coelho, Chase J.; Rosenbaum, David A.; Zatsiorsky, Vladimir M.; Latash, Mark L.

    2014-01-01

    In this study, we explored relations between indices of postural sway and perceived comfort during pointing postures performed by standing participants. The participants stood on a force plate, grasped a pointer with the dominant (right) hand, and pointed to targets located at four positions and at two distances from the body. We quantified postural sway over 60-s intervals at each pointing posture, and found no effects of target location or distance on postural sway indices. In contrast, comfort ratings correlated significantly with indices of one of the sway components, trembling. Our observations support the hypothesis that rambling and trembling sway components involve different neurophysiological mechanisms. They also suggest that subjective perception of comfort may be more important than the actual posture for postural sway. PMID:24686189

  19. Geometric morphometrics as a tool for improving the comparative study of behavioural postures

    NASA Astrophysics Data System (ADS)

    Fureix, Carole; Hausberger, Martine; Seneque, Emilie; Morisset, Stéphane; Baylac, Michel; Cornette, Raphaël; Biquand, Véronique; Deleporte, Pierre

    2011-07-01

    Describing postures has always been a central concern when studying behaviour. However, attempts to compare postures objectively at phylogenetical, populational, inter- or intra-individual levels generally either rely upon a few key elements or remain highly subjective. Here, we propose a novel approach, based on well-established geometric morphometrics, to describe and to analyse postures globally (i.e. considering the animal's body posture in its entirety rather than focusing only on a few salient elements, such as head or tail position). Geometric morphometrics is concerned with describing and comparing variation and changes in the form (size and shape) of organisms using the coordinates of a series of homologous landmarks (i.e. positioned in relation to skeletal or muscular cues that are the same for different species for every variety of form and function and that have derived from a common ancestor, i.e. they have a common evolutionary ancestry, e.g. neck, wings, flipper/hand). We applied this approach to horses, using global postures (1) to characterise behaviours that correspond to different arousal levels, (2) to test potential impact of environmental changes on postures. Our application of geometric morphometrics to horse postures showed that this method can be used to characterise behavioural categories, to evaluate the impact of environmental factors (here human actions) and to compare individuals and groups. Beyond its application to horses, this promising approach could be applied to all questions involving the analysis of postures (evolution of displays, expression of emotions, stress and welfare, behavioural repertoires…) and could lead to a whole new line of research.

  20. Sports injuries related to flexibility, posture, acceleration, clinical defects, and previous injury, in high-level players of body contact sports.

    PubMed

    Watson, A W

    2001-04-01

    One-hundred-and-two high-level players of the field-games soccer, Gaelic football and hurling began a two-year investigation into the intrinsic causes of sports-injuries; 86 completed the study. During the first year all injuries, and the time affected by injury, were recorded. The subjects then underwent flexibility tests, an accurate photogrammetric assessment of posture, measures of speed and acceleration, and a clinical assessment of anatomical and physiological factors thought to be associated with the risk of sports injury. Time affected by injury was then recorded for a further 12-month period. Stepwise multiple-regression analysis revealed that the number of days of injury during the second 12-month period could be predicted from (1) the days of injury during the first 12-month period, (2) posture, (3) acceleration over 10m from a standing start, and (4) the number of musculo-skeletal clinical defects. Flexibility scores were not found to be significant predictors of injury. It is suggested that injury prevention programmes should concentrate on improving posture and the rehabilitation from previous injury rather than flexibility; and that research should be undertaken into the effectiveness of such interventions.

  1. The meaning of body experience evaluation in oncology.

    PubMed

    Slatman, Jenny

    2011-12-01

    Evaluation of quality of life, psychic and bodily well-being is becoming increasingly important in oncology aftercare. This type of assessment is mainly carried out by medical psychologists. In this paper I will seek to show that body experience valuation has, besides its psychological usefulness, a normative and practical dimension. Body experience evaluation aims at establishing the way a person experiences and appreciates his or her physical appearance, intactness and competence. This valuation constitutes one's 'body image'. While, first, interpreting the meaning of body image and, second, indicating the limitations of current psychological body image assessment, I argue that the normative aspect of body image is related to the experience of bodily wholeness or bodily integrity. Since this experience is contextualized by a person's life story, evaluation should also focus on narrative aspects. I finally suggest that the interpretation of body experience is not only valuable to assess a person's quality of life after treatment, but that it can also be useful in counseling prior to interventions, since it can support patients in making decisions about interventions that will change their bodies. To apply this type of evaluation to oncology practice, a rich and tailored vocabulary of body experiences has to be developed.

  2. Adaptation of Postural Stability following Stroke.

    PubMed

    Di Fabio, R P

    1997-01-01

    Activities of daily living require both anticipatory and reactive postural adjustments. The influence of stroke on anticipatory and reactive balance behaviors is addressed in this article. Two primary deficits appear to underlie postural instability following stroke. The first deficit type is characterized by a loss of postural muscle recruitment in both lower extremities (not hyperactive stretch reflexes). The second deficit type is related specifically to the lack of limb stabilization on the paretic side of the body. These two categories of deficit might result from the disruption of geocentric and egocentric references for postural stability with cerebrovascular disease. Context-dependent postural responses are either relearned or retained following stroke, but deficits in the sequencing and timing of stabilizing neuromuscular responses appear to be resistant to adaptation. Prior knowledge of an impending balance disturbance improves the initiation of reactive postural adjustments in subjects with stroke but has no effect on the initiation of stabilizing responses associated with voluntary motion. The results suggest that reactive and anticipatory postural adjustments are controlled by different neural mechanisms and may require separate attention in a rehabilitation program. PMID:27620375

  3. [Craniomandibular relations and anti-gravity posture: stabilometric study disclusion wedges].

    PubMed

    Decocq, Philippe; Honoré, Jacques; Auclair-Assaad, Catherine; Sequeira, Henrique; Bocquet, Emmanuelle

    2015-06-01

    Cephalometric parameters are thought to influence static posture. The present work evaluates the relationships between skeletal class or facial divergency, on one hand, and body posture, on the other hand. ANB and FMA angles were measured from profile cephalograms in twenty healthy adults. From each, stabilograms were recorded, with eyes open or shut, and with or without disclusion splints. Without splints, ANB and FMA proved to correlate with the accuracy of postural control. Adding splints changes the average position of the center of pressure exerted on the ground by the body, the anterior-posterior axis, and this effect is consistent with that of the typology. It also alters the displacement of the center of pressure on the same axis. These effects depend on whether the eyes are open or closed. The data reinforces the notion of the impact of cephalometric parameters and their mechanical changes on the static posture. They invite us to take greater account of postural impact of splints used in orthodontic practice.

  4. An Evaluation of the Construct of Body Image.

    ERIC Educational Resources Information Center

    Banfield, Sophie S.; McCabe, Marita P.

    2002-01-01

    Evaluates the efficacy of a multidimensional model of body image that incorporated the dimensions of perception, affect, cognition, and behavior. Results did not support the hypothesized four-factor model, but rather a model that consisted of three factors. The results highlight the multidimensionality of the body image construct and the…

  5. Persons with recurrent low back pain exhibit a rigid postural control strategy

    PubMed Central

    Janssens, Lotte; Knapen, Stefanie; Claeys, Kurt; Suuden-Johanson, Ege

    2008-01-01

    Persons with recurrent low back pain (LBP) have been observed to have altered proprioceptive postural control. These patients seem to adopt a body and trunk stiffening strategy and rely more on ankle proprioception to control their posture during quiet upright standing. The aim of this study is to determine the effect of changing postural condition (stable and unstable support surface) on postural stability and proprioceptive postural control strategy in persons with recurrent LBP. Postural sway characteristics of 21 persons with recurrent LBP and 24 healthy individuals were evaluated in upright posture with or without standing on “foam” for the conditions as follows: (1) control (no vibration); (2) vibration of the triceps surae muscles; (3) paraspinal muscle vibration; (4) vibration of the tibialis anterior muscles. Vision was occluded in all conditions except for one control trial. All trials lasted 60 s. Vibration (60 Hz, 0.5 mm), as a potent stimulus for muscle spindles, was initiated 15 s after the start of the trial for a duration of 15 s. Persons with recurrent LBP showed significantly different postural control strategies favoring ankle muscle proprioceptive control (ratio closer to 1) instead of paraspinal muscle proprioceptive control (ratio closer to 0) for both standing without foam (ratio ankle muscle/paraspinal muscle control = 0.83) (P < 0.0001) and on foam (ratio ankle muscle/paraspinal muscle control = 0.87; P < 0.0001) compared to healthy individuals (0.67 and 0.46, respectively). It is concluded that young persons with recurrent LBP seem to use the same proprioceptive postural control strategy even in conditions when this ankle strategy is not the most appropriate such as standing on an unstable support surface. The adopted proprioceptive postural control strategy might be effective in simple conditions, however, when used in all postural conditions this could be a mechanism to undue spinal loading, pain and recurrences. PMID

  6. Postural Coordination during Socio-motor Improvisation.

    PubMed

    Gueugnon, Mathieu; Salesse, Robin N; Coste, Alexandre; Zhao, Zhong; Bardy, Benoît G; Marin, Ludovic

    2016-01-01

    Human interaction often relies on socio-motor improvisation. Creating unprepared movements during social interaction is not a random process but relies on rules of synchronization. These situations do not only involve people to be coordinated, but also require the adjustment of their posture in order to maintain balance and support movements. The present study investigated posture in such a context. More precisely, we first evaluated the impact of amplitude and complexity of arm movements on posture in solo situation. Then, we assessed the impact of interpersonal coordination on posture using the mirror game in which dyads performed improvised and synchronized movements (i.e., duo situation). Posture was measured through ankle-hip coordination in medio-lateral and antero-posterior directions (ML and AP respectively). Our results revealed the spontaneous emergence of in-phase pattern in ML direction and antiphase pattern in AP direction for solo and duo situations. These two patterns respectively refer to the simultaneous flexion/extension of the ankles and the hips in the same or opposite direction. It suggests different functional roles of postural coordination patterns in each direction, with in-phase supporting task performance in ML (dynamical stability) and antiphase supporting postural control in AP (mechanical stability). Although amplitude of movement did not influence posture, movement complexity disturbed postural stability in both directions. Conversely, interpersonal coordination promoted postural stability in ML but not in AP direction. These results are discussed in terms of the difference in coupling strength between ankle-hip coordination and interpersonal coordination. PMID:27547193

  7. Postural Coordination during Socio-motor Improvisation

    PubMed Central

    Gueugnon, Mathieu; Salesse, Robin N.; Coste, Alexandre; Zhao, Zhong; Bardy, Benoît G.; Marin, Ludovic

    2016-01-01

    Human interaction often relies on socio-motor improvisation. Creating unprepared movements during social interaction is not a random process but relies on rules of synchronization. These situations do not only involve people to be coordinated, but also require the adjustment of their posture in order to maintain balance and support movements. The present study investigated posture in such a context. More precisely, we first evaluated the impact of amplitude and complexity of arm movements on posture in solo situation. Then, we assessed the impact of interpersonal coordination on posture using the mirror game in which dyads performed improvised and synchronized movements (i.e., duo situation). Posture was measured through ankle-hip coordination in medio-lateral and antero-posterior directions (ML and AP respectively). Our results revealed the spontaneous emergence of in-phase pattern in ML direction and antiphase pattern in AP direction for solo and duo situations. These two patterns respectively refer to the simultaneous flexion/extension of the ankles and the hips in the same or opposite direction. It suggests different functional roles of postural coordination patterns in each direction, with in-phase supporting task performance in ML (dynamical stability) and antiphase supporting postural control in AP (mechanical stability). Although amplitude of movement did not influence posture, movement complexity disturbed postural stability in both directions. Conversely, interpersonal coordination promoted postural stability in ML but not in AP direction. These results are discussed in terms of the difference in coupling strength between ankle-hip coordination and interpersonal coordination. PMID:27547193

  8. Postural Coordination during Socio-motor Improvisation.

    PubMed

    Gueugnon, Mathieu; Salesse, Robin N; Coste, Alexandre; Zhao, Zhong; Bardy, Benoît G; Marin, Ludovic

    2016-01-01

    Human interaction often relies on socio-motor improvisation. Creating unprepared movements during social interaction is not a random process but relies on rules of synchronization. These situations do not only involve people to be coordinated, but also require the adjustment of their posture in order to maintain balance and support movements. The present study investigated posture in such a context. More precisely, we first evaluated the impact of amplitude and complexity of arm movements on posture in solo situation. Then, we assessed the impact of interpersonal coordination on posture using the mirror game in which dyads performed improvised and synchronized movements (i.e., duo situation). Posture was measured through ankle-hip coordination in medio-lateral and antero-posterior directions (ML and AP respectively). Our results revealed the spontaneous emergence of in-phase pattern in ML direction and antiphase pattern in AP direction for solo and duo situations. These two patterns respectively refer to the simultaneous flexion/extension of the ankles and the hips in the same or opposite direction. It suggests different functional roles of postural coordination patterns in each direction, with in-phase supporting task performance in ML (dynamical stability) and antiphase supporting postural control in AP (mechanical stability). Although amplitude of movement did not influence posture, movement complexity disturbed postural stability in both directions. Conversely, interpersonal coordination promoted postural stability in ML but not in AP direction. These results are discussed in terms of the difference in coupling strength between ankle-hip coordination and interpersonal coordination.

  9. Human posture experiments under water: ways of applying the findings to microgravity

    NASA Astrophysics Data System (ADS)

    Dirlich, Thomas

    differences between underwater and real microgravity environment were analyzed in greater detail: external forces (buoyancy and grav-ity), required fixation, postural changes by breathing and subject orientation to gravitational vector. Goal of this analysis was to understand the respective effects of each environmental influence on subjects posture observed. Each of the different influences was then quantified and the postural change induced by it calculated. These were then combined using a specially programmed multi-body-simulation tool, making it possible to recompute 3D posture data dy-namically to the environmental influences. The simulation is based on the volumetric 3D model of each subject, specific anthropometric data, such as body-fat or muscle ratio, combined with external forces such as gravity and buoyancy. The recomputed data can then be compared independent from the environmental influences. The recomputed 3D posture data can then be re-evaluated focussing again on possible inter-personal neutral posture archetypes in the subject group. Some examples of recomputed data and inter-personal findings will be given.

  10. A New Standing Posture Detector to Enable People with Multiple Disabilities to Control Environmental Stimulation by Changing Their Standing Posture through a Commercial Wii Balance Board

    ERIC Educational Resources Information Center

    Shih, Ching-Hsiang; Shih, Ching-Tien; Chiang, Ming-Shan

    2010-01-01

    This study assessed whether two persons with multiple disabilities would be able to control environmental stimulation using body swing (changing standing posture) and a Wii Balance Board with a newly developed standing posture detection program (i.e. a new software program turns a Wii Balance Board into a precise standing posture detector). The…

  11. Are simultaneous postural adjustments (SPA) programmed as a function of pointing velocity?

    PubMed

    Fourcade, Paul; Le Bozec, Serge; Bouisset, Simon

    2016-10-01

    This paper deals with the influence of velocity on the postural adjustments that occur during the course of a voluntary movement, that is to say, simultaneous postural adjustments (SPA). To this aim, a pointing task performed at different velocities (V) was considered. Upper limb kinematics and body kinetics were recorded. Using a 2-DOF model, the body was divided into two parts: the right upper limb (termed the "focal" chain) and the rest of the body (termed the "postural" chain). This model allowed us to calculate the kinetics of both subsystems (-F x and [Formula: see text]), with one corresponding to the resultant action on the shoulder (AoSh: -F x) and the other to the resultant reaction of the shoulder (RoSh: [Formula: see text]). The influence of pointing velocity on peak amplitudes and durations was evaluated, as was their instantaneous relationship ("Lissajous ellipse"). The results showed that RoSh and AoSh display similar diphasic profiles, whose amplitude and duration vary with movement velocity. In addition, RoSh is in phase advance of AoSh, the advance being all the shorter as the focal movement velocity becomes faster. Finally, SPA appears to play a dual role, which includes a propulsive action during upper limb acceleration and body stabilization during deceleration. These new findings strengthen the hypothesis that the postural chain is programmed according to task velocity in the same way as the focal chain and that both are coping in order to make the task more efficient.

  12. A 3D reconstruction method of the body envelope from biplanar X-rays: Evaluation of its accuracy and reliability.

    PubMed

    Nérot, Agathe; Choisne, Julie; Amabile, Célia; Travert, Christophe; Pillet, Hélène; Wang, Xuguang; Skalli, Wafa

    2015-12-16

    The aim of this study was to propose a novel method for reconstructing the external body envelope from the low dose biplanar X-rays of a person. The 3D body envelope was obtained by deforming a template to match the surface profiles in two X-rays images in three successive steps: global morphing to adopt the position of a person and scale the template׳s body segments, followed by a gross deformation and a fine deformation using two sets of pre-defined control points. To evaluate the method, a biplanar X-ray acquisition was obtained from head to foot for 12 volunteers in a standing posture. Up to 172 radio-opaque skin markers were attached to the body surface and used as reference positions. Each envelope was reconstructed three times by three operators. Results showed a bias lower than 7mm and a confidence interval (95%) of reproducibility lower than 6mm for all body parts, comparable to other existing methods matching a template onto stereographic photographs. The proposed method offers the possibility of reconstructing body shape in addition to the skeleton using a low dose biplanar X-rays system. PMID:26592437

  13. A 3D reconstruction method of the body envelope from biplanar X-rays: Evaluation of its accuracy and reliability.

    PubMed

    Nérot, Agathe; Choisne, Julie; Amabile, Célia; Travert, Christophe; Pillet, Hélène; Wang, Xuguang; Skalli, Wafa

    2015-12-16

    The aim of this study was to propose a novel method for reconstructing the external body envelope from the low dose biplanar X-rays of a person. The 3D body envelope was obtained by deforming a template to match the surface profiles in two X-rays images in three successive steps: global morphing to adopt the position of a person and scale the template׳s body segments, followed by a gross deformation and a fine deformation using two sets of pre-defined control points. To evaluate the method, a biplanar X-ray acquisition was obtained from head to foot for 12 volunteers in a standing posture. Up to 172 radio-opaque skin markers were attached to the body surface and used as reference positions. Each envelope was reconstructed three times by three operators. Results showed a bias lower than 7mm and a confidence interval (95%) of reproducibility lower than 6mm for all body parts, comparable to other existing methods matching a template onto stereographic photographs. The proposed method offers the possibility of reconstructing body shape in addition to the skeleton using a low dose biplanar X-rays system.

  14. Seated postural hypotension.

    PubMed

    Gorelik, Oleg; Cohen, Natan

    2015-12-01

    Most studies of postural hypotension (PH) have focused on standing PH. Less is known about PH after transition from a supine to sitting position. Moreover, seated PH has not been previously reviewed in the English literature. The aim of this review was to provide current information regarding seating-induced PH. Seventeen studies were reviewed regarding prevalence, methods of evaluation, manifestations, predisposing factors, prognosis, and management of seated PH. Prevalence ranged from 8% among community-dwelling persons to 56% in elderly hospitalized patients. Dizziness and palpitations were the most frequent symptoms. Of a variety of factors that have been identified as predisposing and contributing to seated PH, aging, bed rest, and hypertension were most important. Because seated PH is a common, easily diagnosable and frequently symptomatic condition, especially in elderly inpatients, this disorder warrants attention. Moreover, seating-induced falls in blood pressure and the associated symptoms, may be largely prevented by nonpharmacologic interventions. PMID:26515671

  15. STEADFAST: Psychotherapeutic Intervention Improves Postural Strategy of Somatoform Vertigo and Dizziness

    PubMed Central

    Best, Christoph; Tschan, Regine; Stieber, Nikola; Beutel, Manfred E.; Eckhardt-Henn, Annegret; Dieterich, Marianne

    2015-01-01

    Patients with somatoform vertigo and dizziness (SVD) disorders often report instability of stance or gait and fear of falling. Posturographic measurements indeed indicated a pathological postural strategy. Our goal was to evaluate the effectiveness of a psychotherapeutic and psychoeducational short-term intervention (PTI) using static posturography and psychometric examination. Seventeen SVD patients took part in the study. The effects of PTI on SVD were evaluated with quantitative static posturography. As primary endpoint a quotient characterizing the relation between horizontal and vertical sway was calculated (QH/V), reflecting the individual postural strategy. Results of static posturography were compared to those of age- and gender-matched healthy volunteers (n = 28); baseline measurements were compared to results after PTI. The secondary endpoint was the participation-limiting consequences of SVD as measured by the Vertigo Handicap Questionnaire (VHQ). Compared to the healthy volunteers, the patients with SVD showed a postural strategy characterized by stiffening-up that resulted in a significantly reduced body sway quotient before PTI (patients: QH/V = 0.31 versus controls: QH/V = 0.38; p = 0.022). After PTI the postural behavior normalized, and psychological distress was reduced. PTI therefore appears to modify pathological balance behaviour. The postural strategy of patients with SVD possibly results from anxious anticipatory cocontraction of the antigravity muscles. PMID:26843786

  16. STEADFAST: Psychotherapeutic Intervention Improves Postural Strategy of Somatoform Vertigo and Dizziness.

    PubMed

    Best, Christoph; Tschan, Regine; Stieber, Nikola; Beutel, Manfred E; Eckhardt-Henn, Annegret; Dieterich, Marianne

    2015-01-01

    Patients with somatoform vertigo and dizziness (SVD) disorders often report instability of stance or gait and fear of falling. Posturographic measurements indeed indicated a pathological postural strategy. Our goal was to evaluate the effectiveness of a psychotherapeutic and psychoeducational short-term intervention (PTI) using static posturography and psychometric examination. Seventeen SVD patients took part in the study. The effects of PTI on SVD were evaluated with quantitative static posturography. As primary endpoint a quotient characterizing the relation between horizontal and vertical sway was calculated (Q H/V ), reflecting the individual postural strategy. Results of static posturography were compared to those of age- and gender-matched healthy volunteers (n = 28); baseline measurements were compared to results after PTI. The secondary endpoint was the participation-limiting consequences of SVD as measured by the Vertigo Handicap Questionnaire (VHQ). Compared to the healthy volunteers, the patients with SVD showed a postural strategy characterized by stiffening-up that resulted in a significantly reduced body sway quotient before PTI (patients: Q H/V = 0.31 versus controls: Q H/V = 0.38; p = 0.022). After PTI the postural behavior normalized, and psychological distress was reduced. PTI therefore appears to modify pathological balance behaviour. The postural strategy of patients with SVD possibly results from anxious anticipatory cocontraction of the antigravity muscles.

  17. Effects of viewing affective pictures on sEMG activity of masticatory and postural muscles.

    PubMed

    D'Attilio, Michele; Rodolfino, Daria; Saccucci, Matteo; Abate, Michele; Romani, Gian Luca; Festa, Felice; Merla, Arcangelo

    2013-06-01

    Recently there has been an upsurge of interest in the question to what extent the human motor control system is influenced by the emotional state of the actor. The aim of this study was to evaluate whether emotional inputs modify the activity of masticatory and postural muscles. Twenty healthy young adults viewed affective pictures, while surface electromyography (sEMG) of masticatory and postural muscles was recorded to investigate the coupling between emotional reactions and body muscular activity. One hundred and twenty pictures, chosen from the International Affective Picture System (IAPS), divided in two blocks of six sets, were presented to the subjects. sEMG data were statistically analyzed (RM ANOVA on Ranks). Root Mean Square (RMS) amplitudes, comparing the subsequent sets (Neutral, Unpleasant, Neutral, Pleasant) with the first and the last Baseline set, changed significantly only randomly. The results show that emotional inputs seems not influence the activity of masticatory and postural muscles, recorded by sEMG.

  18. The influence of kayaking and rowing sports experience on postural response to optic flow.

    PubMed

    Chung, Hyun Chae

    2015-02-01

    This study investigated the postural response of kayakers and rowers to imposed optic flow. The athletes, with experience in unstable water environments, should have a specific postural response to optic flow. 12 male participants with kayaking and rowing experience and 12 with no specific sports experience were asked to stand still with and without room motion. This study varied the amplitude and frequency of room motion and evaluated the trajectory of the center of pressure. The kayaking and rowing group were less influenced by imposed optic flow, and body sway was more closely synchronized to the oscillating room compared to the Non-athlete group. These results suggest that postural adaptation occurs in association with experience in kayaking and rowing. PMID:25650510

  19. Social Postural Coordination

    ERIC Educational Resources Information Center

    Varlet, Manuel; Marin, Ludovic; Lagarde, Julien; Bardy, Benoit G.

    2011-01-01

    The goal of the current study was to investigate whether a visual coupling between two people can produce spontaneous interpersonal postural coordination and change their intrapersonal postural coordination involved in the control of stance. We examined the front-to-back head displacements of participants and the angular motion of their hip and…

  20. Postural awareness among dental students in Jizan, Saudi Arabia

    PubMed Central

    Kanaparthy, Aruna; Kanaparthy, Rosaiah; Boreak, Nezar

    2015-01-01

    Objective: The study was conducted to assess the postural awareness of dental students in Jizan, Saudi Arabia. Materials and Methods: Close-ended, self-administered questionnaires were used for data collection in the survey. The questionnaire was prepared by observing the positions of students working in the clinics and the common mistakes they make with regard to their postures. The questionnaires were distributed among the dental students who were present and reported to work in the clinics. Levels of postural awareness and the relationship between postural awareness and the degree of musculoskeletal disorder (MSD) among the students was evaluated. This study was carried out in the College of Dental Sciences and Hospital, Jizan. Statistical Analysis: The level of knowledge of postural awareness was evaluated and correlated with the presence or absence of the MSDs. Categorical variables were compared using Chi-square test. P values of less than 0.05 were considered statistically significant. Results: A total of 162 dental students from the age group of 20–25 years were included in the survey, of which 134 dentists responded (83%). When their postural awareness was evaluated, results showed that 89% of the students had poor-to-medium levels of postural awareness. The relation between postural awareness and prevalence of MSDs indicated that 75% of the students with poor awareness, 49% of the students with average awareness, and 40% of the students with good awareness have MSDs. The results were statistically significant (0.002127, which is <0.005) stating that better awareness about proper postures while working helps to minimize the risk of MSDs. Conclusion: Evaluation of levels of postural awareness showed that 21% of the students had poor postural awareness, 67% had average awareness, and 11% had good postural awareness. The analysis of results showed that those students with low-to-average postural awareness had significantly greater prevalence of MSDs. PMID

  1. Evaluating the validity of using unverified indices of body condition

    USGS Publications Warehouse

    Schamber, J.L.; Esler, Daniel; Flint, P.L.

    2009-01-01

    Condition indices are commonly used in an attempt to link body condition of birds to ecological variables of interest, including demographic attributes such as survival and reproduction. Most indices are based on body mass adjusted for structural body size, calculated as simple ratios or residuals from regressions. However, condition indices are often applied without confirming their predictive value (i.e., without being validated against measured values of fat and protein), which we term 'unverified' use. We evaluated the ability of a number of unverified indices frequently found in the literature to predict absolute and proportional levels of fat and protein across five species of waterfowl. Among indices we considered, those accounting for body size never predicted absolute protein more precisely than body mass, however, some indices improved predictability of fat, although the form of the best index varied by species. Further, the gain in precision by using a condition index to predict either absolute or percent fat was minimal (rise in r2???0.13), and in many cases model fit was actually reduced. Our data agrees with previous assertions that the assumption that indices provide more precise indicators of body condition than body mass alone is often invalid. We strongly discourage the use of unverified indices, because subjectively selecting indices likely does little to improve precision and might in fact decrease predictability relative to using body mass alone. ?? 2009 The Authors.

  2. Effect of absence of vision on posture.

    PubMed

    Alotaibi, Abdullah Z; Alghadir, Ahmad; Iqbal, Zaheen A; Anwer, Shahnawaz

    2016-04-01

    [Purpose] The visual system is one of the sensory systems that enables the body to assess and process information about the external environment. In the absence of vision, a blind person loses contact with the outside world and develops faulty motor patterns, which results in postural deficiencies. However, literature regarding the development of such deficiencies is limited. The aim of this study was to discuss the effect of absence of vision on posture, the possible biomechanics behind the resulting postural deficiencies, and strategies to correct and prevent them. [Subjects and Methods] Various electronic databases including PubMed, Medline, and Google scholar were examined using the words "body", "posture", "blind" and "absence of vision". References in the retrieved articles were also examined for cross-references. The search was limited to articles in the English language. [Results] A total of 74 papers were shortlisted for this review, most of which dated back to the 1950s and 60s. [Conclusion] Blind people exhibit consistent musculoskeletal deformities. Absence of vision leads to numerous abnormal sensory and motor interactions that often limit blind people in isolation. Rehabilitation of the blind is a multidisciplinary task. Specialists from different fields need to diagnose and treat the deficiencies of the blind together as a team. Before restoring the normal mechanics of posture and gait, the missing link with the external world should be reestablished. PMID:27190486

  3. Postural orientation in microgravity depends on straightening up movement performed

    NASA Astrophysics Data System (ADS)

    Vaugoyeau, Marianne; Assaiante, Christine

    2009-08-01

    Whether the vertical body orientation depends on the initial posture and/or the type of straightening up movement is the main question raised in this paper. Another objective was to specify the compensatory role of visual input while adopting an erected posture during microgravity. The final body orientation was analysed in microgravity during parabolic flights. After either (1) straightening up movement from a crouching or (2) a sitting posture, with and without vision. The main results are the following: (1) a vertical erected final posture is correctly achieved after sit to stand movement, whereas all subjects were tilted forward after straightening up from a crouching posture and (2) vision may contribute to correct final posture. These results suggest the existence of a re-weighting of the remaining sensory information, visual information, contact cutaneous cues and proprioceptive information under microgravity condition. We can put forward the alternative hypothesis that the control of body orientation under microgravity condition may also be achieved on the basis of a postural body scheme, that seems to be dependant on the type of movement and/ or the initial position of the whole body.

  4. Postural optimization during functional reach while kneeling and standing.

    PubMed

    Fujisawa, Hiroyuki; Suzuki, Hiroto; Kawakami, Shingo; Murakami, Kenichi; Suzuki, Makoto

    2016-08-01

    [Purpose] The purpose of the present study was to examine the validity of functional reach models by comparing actual values with estimated values. [Subjects and Methods] Twenty-eight volunteers were included in this study (male: 14, female: 14, age: 21 ± 1 years, height: 166.8 ± 9.0 cm, and body mass: 60.1 ± 8.5 kg). The maximum forward fingertip position and joint angles were measured using the original equipment. In addition, the maximum forward fingertip position, shoulder joint angle, and knee or ankle joint angle were estimated using the functional reach model. [Results] The correlation coefficients between actual data and estimated data for the maximum forward fingertip position, shoulder joint angle, and ankle joint angle while standing were 0.93, 0.83, and 0.73, respectively. The correlation coefficients between actual data and estimated data for the maximum forward fingertip position, shoulder joint angle, and knee joint angle while kneeling were 0.86, 0.81, and 0.72, respectively. [Conclusion] The validity of both functional reach models in estimating optimal posture was confirmed. Therefore, the functional reach model is useful for evaluation of postural control and optimal postural control exercises. PMID:27630433

  5. Postural optimization during functional reach while kneeling and standing

    PubMed Central

    Fujisawa, Hiroyuki; Suzuki, Hiroto; Kawakami, Shingo; Murakami, Kenichi; Suzuki, Makoto

    2016-01-01

    [Purpose] The purpose of the present study was to examine the validity of functional reach models by comparing actual values with estimated values. [Subjects and Methods] Twenty-eight volunteers were included in this study (male: 14, female: 14, age: 21 ± 1 years, height: 166.8 ± 9.0 cm, and body mass: 60.1 ± 8.5 kg). The maximum forward fingertip position and joint angles were measured using the original equipment. In addition, the maximum forward fingertip position, shoulder joint angle, and knee or ankle joint angle were estimated using the functional reach model. [Results] The correlation coefficients between actual data and estimated data for the maximum forward fingertip position, shoulder joint angle, and ankle joint angle while standing were 0.93, 0.83, and 0.73, respectively. The correlation coefficients between actual data and estimated data for the maximum forward fingertip position, shoulder joint angle, and knee joint angle while kneeling were 0.86, 0.81, and 0.72, respectively. [Conclusion] The validity of both functional reach models in estimating optimal posture was confirmed. Therefore, the functional reach model is useful for evaluation of postural control and optimal postural control exercises. PMID:27630433

  6. Postural optimization during functional reach while kneeling and standing

    PubMed Central

    Fujisawa, Hiroyuki; Suzuki, Hiroto; Kawakami, Shingo; Murakami, Kenichi; Suzuki, Makoto

    2016-01-01

    [Purpose] The purpose of the present study was to examine the validity of functional reach models by comparing actual values with estimated values. [Subjects and Methods] Twenty-eight volunteers were included in this study (male: 14, female: 14, age: 21 ± 1 years, height: 166.8 ± 9.0 cm, and body mass: 60.1 ± 8.5 kg). The maximum forward fingertip position and joint angles were measured using the original equipment. In addition, the maximum forward fingertip position, shoulder joint angle, and knee or ankle joint angle were estimated using the functional reach model. [Results] The correlation coefficients between actual data and estimated data for the maximum forward fingertip position, shoulder joint angle, and ankle joint angle while standing were 0.93, 0.83, and 0.73, respectively. The correlation coefficients between actual data and estimated data for the maximum forward fingertip position, shoulder joint angle, and knee joint angle while kneeling were 0.86, 0.81, and 0.72, respectively. [Conclusion] The validity of both functional reach models in estimating optimal posture was confirmed. Therefore, the functional reach model is useful for evaluation of postural control and optimal postural control exercises.

  7. Reliability of photographic posture analysis of adolescents

    PubMed Central

    Hazar, Zeynep; Karabicak, Gul Oznur; Tiftikci, Ugur

    2015-01-01

    [Purpose] Postural problems of adolescents needs to be evaluated accurately because they may lead to greater problems in the musculoskeletal system as they develop. Although photographic posture analysis has been frequently used, more simple and accessible methods are still needed. The purpose of this study was to investigate the inter- and intra-rater reliability of photographic posture analysis using MB-ruler software. [Subjects and Methods] Subjects were 30 adolescents (15 girls and 15 boys, mean age: 16.4±0.4 years, mean height 166.3±6.7 cm, mean weight 63.8±15.1 kg) and photographs of their habitual standing posture photographs were taken in the sagittal plane. For the evaluation of postural angles, reflective markers were placed on anatomical landmarks. For angular measurements, MB-ruler (Markus Bader- MB Software Solutions, triangular screen ruler) was used. Photographic evaluations were performed by two observers with a repetition after a week. Test-retest and inter-rater reliability evaluations were calculated using intra-class correlation coefficients (ICC). [Results] Inter-rater (ICC>0.972) and test-retest (ICC>0.774) reliability were found to be in the range of acceptable to excellent. [Conclusion] Reference angles for postural evaluation were found to be reliable and repeatable. The present method was found to be an easy and non-invasive method and it may be utilized by researchers who are in search of an alternative method for photographic postural assessments. PMID:26644658

  8. Reliability of photographic posture analysis of adolescents.

    PubMed

    Hazar, Zeynep; Karabicak, Gul Oznur; Tiftikci, Ugur

    2015-10-01

    [Purpose] Postural problems of adolescents needs to be evaluated accurately because they may lead to greater problems in the musculoskeletal system as they develop. Although photographic posture analysis has been frequently used, more simple and accessible methods are still needed. The purpose of this study was to investigate the inter- and intra-rater reliability of photographic posture analysis using MB-ruler software. [Subjects and Methods] Subjects were 30 adolescents (15 girls and 15 boys, mean age: 16.4±0.4 years, mean height 166.3±6.7 cm, mean weight 63.8±15.1 kg) and photographs of their habitual standing posture photographs were taken in the sagittal plane. For the evaluation of postural angles, reflective markers were placed on anatomical landmarks. For angular measurements, MB-ruler (Markus Bader- MB Software Solutions, triangular screen ruler) was used. Photographic evaluations were performed by two observers with a repetition after a week. Test-retest and inter-rater reliability evaluations were calculated using intra-class correlation coefficients (ICC). [Results] Inter-rater (ICC>0.972) and test-retest (ICC>0.774) reliability were found to be in the range of acceptable to excellent. [Conclusion] Reference angles for postural evaluation were found to be reliable and repeatable. The present method was found to be an easy and non-invasive method and it may be utilized by researchers who are in search of an alternative method for photographic postural assessments.

  9. Poor sitting posture and a heavy schoolbag as contributors to musculoskeletal pain in children: an ergonomic school education intervention program

    PubMed Central

    Syazwan, AI; Azhar, MN Mohamad; Anita, AR; Azizan, HS; Shaharuddin, MS; Hanafiah, J Muhamad; Muhaimin, AA; Nizar, AM; Rafee, B Mohd; Ibthisham, A Mohd; Kasani, Adam

    2011-01-01

    Objectives The purpose of this study was to evaluate a multidisciplinary, interventional, ergonomic education program designed to reduce the risk of musculoskeletal problems by reducing schoolbag weight and correcting poor sitting posture. Methods Data were collected twice before and twice following intervention using the Standardized Nordic Body Map Questionnaire, a rapid upper limb assessment for posture evaluation, and schoolbag weight measurement in children aged 8 and 11 years attending two schools within the central region of Malaysia. Results Students who received the ergonomic intervention reported significant improvements in their sitting posture in a classroom environment and reduction of schoolbag weight as compared with the controls. Conclusion A single-session, early intervention, group ergonomics education program for children aged 8 and 11 years is appropriate and effective, and should be considered as a strategy to reduce musculoskeletal pain among schoolchildren in this age group. PMID:22003301

  10. Physical Workload Analysis Among Small Industry Activities Using Postural Data.

    PubMed

    Ahasan; Väyrynen; Kirvesoja

    1996-01-01

    Small industry workers are often involved in manual handling operations that require awkward body postures, so musculoskeletal disorders and occupational injuries are a major problem. In this study, various types of tasks were recorded with a video camera to chart and analyze different postures by computerized OWAS (Ovako Working Posture Analysing System). Collected data showed that poor postures were adopted, not only for lifting or hammering operation, but also for other tasks; mostly with bent and twisted back. The main aim was to determine the physical workload by identifying harmful postures and to develop recommendations for improving the existing situation. Forty-eight male workers from 8 different units (mean age: 37) participated. The performed activities were then divided into 26 sub-tasks. Altogether 1534 postures were selected for analysis. Then they were classified into different OAC (OWAS Action Categories). From all the observation, unhealthy postures, for which corrective measures had to be considered immediately (i.e., 10.6% classified as OAC III and 3.3%--as OAC IV) were found. The applied method was useful in determining the physical workload by locating potential activities due to harmful postures, providing a detailed description with analysis, and suggesting successful means to reduce postural load.

  11. Eye Movements Affect Postural Control in Young and Older Females

    PubMed Central

    Thomas, Neil M.; Bampouras, Theodoros M.; Donovan, Tim; Dewhurst, Susan

    2016-01-01

    Visual information is used for postural stabilization in humans. However, little is known about how eye movements prevalent in everyday life interact with the postural control system in older individuals. Therefore, the present study assessed the effects of stationary gaze fixations, smooth pursuits, and saccadic eye movements, with combinations of absent, fixed and oscillating large-field visual backgrounds to generate different forms of retinal flow, on postural control in healthy young and older females. Participants were presented with computer generated visual stimuli, whilst postural sway and gaze fixations were simultaneously assessed with a force platform and eye tracking equipment, respectively. The results showed that fixed backgrounds and stationary gaze fixations attenuated postural sway. In contrast, oscillating backgrounds and smooth pursuits increased postural sway. There were no differences regarding saccades. There were also no differences in postural sway or gaze errors between age groups in any visual condition. The stabilizing effect of the fixed visual stimuli show how retinal flow and extraocular factors guide postural adjustments. The destabilizing effect of oscillating visual backgrounds and smooth pursuits may be related to more challenging conditions for determining body shifts from retinal flow, and more complex extraocular signals, respectively. Because the older participants matched the young group's performance in all conditions, decreases of posture and gaze control during stance may not be a direct consequence of healthy aging. Further research examining extraocular and retinal mechanisms of balance control and the effects of eye movements, during locomotion, is needed to better inform fall prevention interventions.

  12. Eye Movements Affect Postural Control in Young and Older Females

    PubMed Central

    Thomas, Neil M.; Bampouras, Theodoros M.; Donovan, Tim; Dewhurst, Susan

    2016-01-01

    Visual information is used for postural stabilization in humans. However, little is known about how eye movements prevalent in everyday life interact with the postural control system in older individuals. Therefore, the present study assessed the effects of stationary gaze fixations, smooth pursuits, and saccadic eye movements, with combinations of absent, fixed and oscillating large-field visual backgrounds to generate different forms of retinal flow, on postural control in healthy young and older females. Participants were presented with computer generated visual stimuli, whilst postural sway and gaze fixations were simultaneously assessed with a force platform and eye tracking equipment, respectively. The results showed that fixed backgrounds and stationary gaze fixations attenuated postural sway. In contrast, oscillating backgrounds and smooth pursuits increased postural sway. There were no differences regarding saccades. There were also no differences in postural sway or gaze errors between age groups in any visual condition. The stabilizing effect of the fixed visual stimuli show how retinal flow and extraocular factors guide postural adjustments. The destabilizing effect of oscillating visual backgrounds and smooth pursuits may be related to more challenging conditions for determining body shifts from retinal flow, and more complex extraocular signals, respectively. Because the older participants matched the young group's performance in all conditions, decreases of posture and gaze control during stance may not be a direct consequence of healthy aging. Further research examining extraocular and retinal mechanisms of balance control and the effects of eye movements, during locomotion, is needed to better inform fall prevention interventions. PMID:27695412

  13. Postural development in school children: a cross-sectional study

    PubMed Central

    Lafond, Danik; Descarreaux, Martin; Normand, Martin C; Harrison, Deed E

    2007-01-01

    Background Little information on quantitative sagittal plane postural alignment and evolution in children exists. The objectives of this study are to document the evolution of upright, static, sagittal posture in children and to identify possible critical phases of postural evolution (maturation). Methods A total of 1084 children (aged 4–12 years) received a sagittal postural evaluation with the Biotonix postural analysis system. Data were retrieved from the Biotonix internet database. Children were stratified and analyzed by years of age with n = 36 in the youngest age group (4 years) and n = 184 in the oldest age group (12 years). Children were analyzed in the neutral upright posture. Variables measured were sagittal translation distances in millimeters of: the knee relative to the tarsal joint, pelvis relative to the tarsal joint, shoulder relative to the tarsal joint, and head relative to the tarsal joint. A two-way factorial ANOVA was used to test for age and gender effects on posture, while polynomial trend analyses were used to test for increased postural displacements with years of age. Results Two-way ANOVA yielded a significant main effect of age for all 4 sagittal postural variables and gender for all variables except head translation. No age × gender interaction was found. Polynomial trend analyses showed a significant linear association between child age and all four postural variables: anterior head translation (p < 0.001), anterior shoulder translation (p < 0.001), anterior pelvic translation (p < 0.001), anterior knee translation (p < 0.001). Between the ages of 11 and 12 years, for anterior knee translation, T-test post hoc analysis revealed only one significant rough break in the continuity of the age related trend. Conclusion A significant linear trend for increasing sagittal plane postural translations of the head, thorax, pelvis, and knee was found as children age from 4 years to 12 years. These postural translations provide preliminary

  14. Computer users' postures and associations with workstation characteristics.

    PubMed

    Gerr, F; Marcus, M; Ortiz, D; White, B; Jones, W; Cohen, S; Gentry, E; Edwards, A; Bauer, E

    2000-01-01

    This investigation tested the hypotheses that (1) physical workstation dimensions are important determinants of operator posture, (2) specific workstation characteristics systematically affect worker posture, and (3) computer operators assume "neutral" upper limb postures while keying. Operator head, neck, and upper extremity posture and selected workstation dimensions and characteristics were measured among 379 computer users. Operator postures were measured with manual goniometers, workstation characteristics were evaluated by observation, and workstation dimensions by direct measurement. Considerably greater variability in all postures was observed than was expected from application of basic geometric principles to measured workstation dimensions. Few strong correlations were observed between worker posture and workstation physical dimensions; findings suggest that preference is given to keyboard placement with respect to the eyes (r = 0.60 for association between keyboard height and seated elbow height) compared with monitor placement with respect to the eyes (r = 0.18 for association between monitor height and seated eye height). Wrist extension was weakly correlated with keyboard height (r = -0.24) and virtually not at all with keyboard thickness (r = 0.07). Use of a wrist rest was associated with decreased wrist flexion (21.9 versus 25.1 degrees, p < 0.01). Participants who had easily adjustable chairs had essentially the same neck and upper limb postures as did those with nonadjustable chairs. Sixty-one percent of computer operators were observed in nonneutral shoulder postures and 41% in nonneutral wrist postures. Findings suggest that (1) workstation dimensions are not strong determinants of at least several neck and upper extremity postures among computer operators, (2) only some workstation characteristics affect posture, and (3) contrary to common recommendations, a large proportion of computer users do not work in so-called neutral postures.

  15. Observations of working postures in garages using the Ovako Working posture Analysing System (OWAS) and consequent workload reduction recommendations.

    PubMed

    Kant, I; Notermans, J H; Borm, P J

    1990-02-01

    The working postures of mechanics (n = 84) in 42 garages were observed using the Ovako Working posture Analysis System (OWAS). During observation, both working postures and work activities were recorded. A computer program was developed for the data analyses. Using this program it is possible to calculate the working posture load for each work activity and the contribution of a specific activity to the total working posture load. This is a substantial extension of the original OWAS method. Five out of 19 observed postures of the body members were classified as Action Category 2, which suggests they were slightly harmful to the musculoskeletal system and likely to cause discomfort. Of the so-called typical working postures, 31.9% was classified in Action Category 2, suggesting that during a substantial part of the working day typical working postures occur which are at least slightly harmful to the musculoskeletal system. Moreover, those work activities principally causing the workload to fall in OWAS' higher Action Categories were identified. For each of these three work activities an alternative work method was observed. The data show that in all three work activities the use of a vehicle lift reduces the number of poor working postures thereby reducing the load on the musculoskeletal system.

  16. Effect of different insoles on postural balance: a systematic review.

    PubMed

    Christovão, Thaluanna Calil Lourenço; Neto, Hugo Pasini; Grecco, Luanda André Collange; Ferreira, Luiz Alfredo Braun; Franco de Moura, Renata Calhes; Eliege de Souza, Maria; Franco de Oliveira, Luis Vicente; Oliveira, Claudia Santos

    2013-10-01

    [Purpose] The aim of the present study was to perform a systematic review of the literature on the effect of different insoles on postural balance. [Subjects and Methods] A systematic review was conducted of four databases. The papers retrieved were evaluated based on the following inclusion criteria: 1) design: controlled clinical trial; 2) intervention: insole; 3) outcome: change in static postural balance; and 4) year of publication: 2005 to 2012. [Results] Twelve controlled trials were found comparing the effects of different insoles on postural balance. The papers had methodological quality scores of 3 or 4 on the PEDro scale. [Conclusion] Insoles have benefits that favor better postural balance and control.

  17. Bed posture classification for pressure ulcer prevention.

    PubMed

    Yousefi, R; Ostadabbas, S; Faezipour, M; Farshbaf, M; Nourani, M; Tamil, L; Pompeo, M

    2011-01-01

    Pressure ulcer is an age-old problem imposing a huge cost to our health care system. Detecting and keeping record of the patient's posture on bed, help care givers reposition patient more efficiently and reduce the risk of developing pressure ulcer. In this paper, a commercial pressure mapping system is used to create a time-stamped, whole-body pressure map of the patient. An image-based processing algorithm is developed to keep an unobtrusive and informative record of patient's bed posture over time. The experimental results show that proposed algorithm can predict patient's bed posture with up to 97.7% average accuracy. This algorithm could ultimately be used with current support surface technologies to reduce the risk of ulcer development. PMID:22255993

  18. Body image during pregnancy: an evaluation of the suitability of the body attitudes questionnaire

    PubMed Central

    2012-01-01

    Background Available data suggest that body dissatisfaction is common during pregnancy and may even be a precursor to post-natal depression. However, in order to accurately identify at-risk women, it is essential to first establish that body image measures function appropriately in pregnant populations. Our study examines the suitability of the Body Attitudes Questionnaire (BAQ) for measuring body dissatisfaction among pregnant women by comparing the psychometric functioning of the BAQ: (1) across key phases of pregnancy, and (2) between pregnant and non-pregnant women. Methods A total of 176 pregnant women from Melbourne, Victoria filled out a questionnaire battery containing demographic questions and the Body Attitudes Questionnaire at 16, 24, and 32 weeks during pregnancy. A comparison group of 148 non-pregnant women also completed the questionnaire battery at Time 1. Evaluations of the psychometric properties of the BAQ consisted of a series of measurement invariance tests conducted within a structural equation modelling framework. Results Although the internal consistency and factorial validity of the subscales of the BAQ were established across time and also in comparisons between pregnant and non-pregnant women, measurement invariance tests showed non-invariant item intercepts across pregnancy and also in comparison with the non-pregnant subgroup. Inspection of modification indices revealed a complex, non-uniform pattern of differences in item intercepts across groups. Conclusions Collectively, our findings suggest that comparisons of body dissatisfaction between pregnant and non-pregnant women (at least based on the BAQ) are likely to be conflated by differential measurement biases that serve to undermine attempts to accurately assess level of body dissatisfaction. Researchers should be cautious in assessments of body dissatisfaction among pregnant women until a suitable measure has been established for use in this population. Given the fact that body

  19. Evaluation of body weight, body mass index, and body fat percentage changes in early stages of fixed orthodontic therapy

    PubMed Central

    Sandeep, K. Sai; Singaraju, Gowri Sankar; Reddy, V. Karunakar; Mandava, Prasad; Bhavikati, Venkata N.; Reddy, Rohit

    2016-01-01

    Aim: The aim of this study was to evaluate and compare the changes in body weight, body mass index (BMI), and body fat percentage (BFP) during the initial stages of fixed orthodontic treatment. Materials and Methods: The sample for this observational prospective study included 68 individuals with fixed orthodontic appliance in the age group of 18–25 years of both the sexes (25 males and 43 females). The control group consisted of 60 individuals (24 males and 36 females). The weight, BMI, and BFP were measured using a Body Composition Monitor at three points of time “T1” initial; “T2” after 1 month; and “T2” after 3 months. The results were tabulated and analyzed with the Statistical Package for the Social Sciences software. The mean changes between different parameters in both the study and control groups and between males and females in the study group was compared by using two-tailed unpaired student's t-test. The statistical significance is set atP ≤ 0.05. Results: There was an overall decrease in the body weight, BMI, and BFP after 1 month in the study cohort, which was statistically significant compared to the control group (P < 0.0001). This was followed by an increase in the parameters after the end of the 3rd month. Comparison of the parameters between the study and control group at the start of the treatment and at the end of the 3rd month had no statistical significance. There was a marked variation in the changes of these parameters between males and females of the study group, which is statistically significant (<0.0001). Conclusion: There is a definite reduction in the weight, BMP, and BMI at the end of the first month followed by a gain of weight, but not at the initial point by the end of the 3rd month. PMID:27583224

  20. Reduced Processing of Facial and Postural Cues in Social Anxiety: Insights from Electrophysiology

    PubMed Central

    Rossignol, Mandy; Fisch, Sophie-Alexandra; Maurage, Pierre; Joassin, Frédéric; Philippot, Pierre

    2013-01-01

    Social anxiety is characterized by fear of evaluative interpersonal situations. Many studies have investigated the perception of emotional faces in socially anxious individuals and have reported biases in the processing of threatening faces. However, faces are not the only stimuli carrying an interpersonal evaluative load. The present study investigated the processing of emotional body postures in social anxiety. Participants with high and low social anxiety completed an attention-shifting paradigm using neutral, angry and happy faces and postures as cues. We investigated early visual processes through the P100 component, attentional fixation on the P2, structural encoding mirrored by the N170, and attentional orientation towards stimuli to detect with the P100 locked on target occurrence. Results showed a global reduction of P100 and P200 responses to faces and postures in socially anxious participants as compared to non-anxious participants, with a direct correlation between self-reported social anxiety levels and P100 and P200 amplitudes. Structural encoding of cues and target processing were not modulated by social anxiety, but socially anxious participants were slower to detect the targets. These results suggest a reduced processing of social postural and facial cues in social anxiety. PMID:24040403

  1. Postural alignment in children with Duchenne muscular dystrophy and its relationship with balance

    PubMed Central

    Baptista, Cyntia R. J. A.; Costa, Andreia A.; Pizzato, Tatiana M.; Souza, Francine B.; Mattiello-Sverzut, Ana C.

    2014-01-01

    Background In Duchenne muscular dystrophy, functional deficits seem to arise from body misalignment, deconditioning, and obesity secondary to weakness and immobility. The question remains about the effects of postural deviations on the functional balance of these children. Objectives To identify and quantify postural deviations in children with DMD in comparison to non-affected children (eutrophic and overweight/obese), exploring relationships between posture and function. Method This case-control study evaluated 29 participants aged 6 to 11 years: 10 DMD (DG), 10 eutrophic (EG), and 9 overweight/obese (OG). Digital photogrammetry and SAPo program were used to measure postural alignment and the Pediatric Balance Scale (PBS) was used to measure balance. The Kruskall-Wallis and Dunn post-hoc tests were used for inter-group comparison of posture and balance. Spearman's coefficient tested the correlation between postural and balance variables. Results The horizontal pelvic alignment data indicated that the anteversion of the DG was similar to that of the OG and twice that of the EG (p<0.05). Compared to the EG, the DG and OG showed an increased forward position of the center of mass (p<0.05). There was a moderate and weak correlation between the PBS score and horizontal pelvic alignment (0.58 and 0.47-left/right). The PBS showed a weak correlation with asymmetries in the sagittal plane (-0.39). The PBS scores for the OG and EG suggest that obesity did not have a deleterious effect on balance. Conclusions The balance deficit in children with DMD was accompanied by an increased forward position of the center of mass and significant pelvic anteversion that constitutes a compensatory strategy to guarantee similar performance to the children not affected by the disease. PMID:24838810

  2. Electromyographic response in inferior head of human lateral pterygoid muscle to anteroposterior postural change during opening and closing of mouth.

    PubMed

    Yotsuya, Mamoru; Sato, Toru; Kawamura, Sadayuki; Furuya, Eiji; Saito, Fumiaki; Hisanaga, Ryuichi; Onodera, Kozue

    2009-01-01

    The purpose of this study was to investigate the influence of anteroposterior postural change on electromyography (EMG) activity in the lateral pterygoid muscle. Subjects consisted of 7 patients attending this hospital for close examination. The inferior heads of the lateral pterygoid and masseter muscles were chosen as evaluation sites. For the EMG recordings, the test movement was opening and closing of the mouth; postural conditions were the upright and supine positions. The mean value of EMG activity in the inferior head of the lateral pterygoid muscle was calculated. During mouth-opening in 5 out of the 7 patients, and during mouth-closing in 2 out of the 7 patients, mean value of EMG activity differed significantly with body position. Mean value of EMG activity was reduced in the supine position. The results revealed that anteroposterior postural change affected mean value of EMG activity in this muscle. PMID:20179394

  3. The Effect of Training on Postural Control in Dyslexic Children.

    PubMed

    Goulème, Nathalie; Gérard, Christophe-Loïc; Bucci, Maria Pia

    2015-01-01

    The aim of this study was to explore whether a short postural training period could affect postural stability in dyslexic children. Postural performances were evaluated using Multitest Equilibre from Framiral. Posture was recorded in three different viewing conditions (eyes open fixating a target, eyes closed and eyes open with perturbed vision) and in two different postural conditions (on stable and unstable support). Two groups of dyslexic children participated in the study, i.e. G1: 16 dyslexic participants (mean age 9.9 ± 0.3 years) who performed short postural training and G2: 16 dyslexic participants of similar ages (mean age 9.1 ± 0.3 years) who did not perform any short postural training. Findings showed that short postural training improved postural stability on unstable support surfaces with perturbed vision: indeed the surface, the mean velocity of CoP and the spectral power indices in both directions decreased significantly, and the cancelling time in the antero-posterior direction improved significantly. Such improvement could be due to brain plasticity, which allows better performance in sensory process and cerebellar integration.

  4. The Effect of Training on Postural Control in Dyslexic Children

    PubMed Central

    Goulème, Nathalie; Gérard, Christophe-Loïc; Bucci, Maria Pia

    2015-01-01

    The aim of this study was to explore whether a short postural training period could affect postural stability in dyslexic children. Postural performances were evaluated using Multitest Equilibre from Framiral. Posture was recorded in three different viewing conditions (eyes open fixating a target, eyes closed and eyes open with perturbed vision) and in two different postural conditions (on stable and unstable support). Two groups of dyslexic children participated in the study, i.e. G1: 16 dyslexic participants (mean age 9.9 ± 0.3 years) who performed short postural training and G2: 16 dyslexic participants of similar ages (mean age 9.1 ± 0.3 years) who did not perform any short postural training. Findings showed that short postural training improved postural stability on unstable support surfaces with perturbed vision: indeed the surface, the mean velocity of CoP and the spectral power indices in both directions decreased significantly, and the cancelling time in the antero-posterior direction improved significantly. Such improvement could be due to brain plasticity, which allows better performance in sensory process and cerebellar integration. PMID:26162071

  5. Relationship between static postural control and the level of functional abilities in children with cerebral palsy

    PubMed Central

    Pavão, Sílvia L.; Nunes, Gabriela S.; Santos, Adriana N.; Rocha, Nelci A. C. F.

    2014-01-01

    Background: Postural control deficits can impair functional performance in children with cerebral palsy (CP) in daily living activities. Objective: To verify the relationship between standing static postural control and the functional ability level in children with CP. Method: The postural control of 10 children with CP (gross motor function levels I and II) was evaluated during static standing on a force platform for 30 seconds. The analyzed variables were the anteroposterior (AP) and mediolateral (ML) displacement of the center of pressure (CoP) and the area and velocity of the CoP oscillation. The functional abilities were evaluated using the mean Pediatric Evaluation of Disability Inventory (PEDI) scores, which evaluated self-care, mobility and social function in the domains of functional abilities and caregiver assistance. Results: Spearman's correlation test found a relationship between postural control and functional abilities. The results showed a strong negative correlation between the variables of ML displacement of CoP, the area and velocity of the CoP oscillation and the PEDI scores in the self-care and caregiver assistance domains. Additionally, a moderate negative correlation was found between the area of the CoP oscillation and the mobility scores in the caregiver assistance domain. We used a significance level of 5% (p <0.05). Conclusions: We observed that children with cerebral palsy with high CoP oscillation values had lower caregiver assistance scores for activities of daily living (ADL) and consequently higher levels of caregiver dependence. These results demonstrate the repercussions of impairments to the body structure and function in terms of the activity levels of children with CP such that postural control impairments in these children lead to higher requirements for caregiver assistance. PMID:25054383

  6. Autoimmune Basis for Postural Tachycardia Syndrome

    ClinicalTrials.gov

    2016-10-14

    Postural Orthostatic Tachycardia Syndrome; Postural Tachycardia Syndrome; Tachycardia; Arrhythmias, Cardiac; Autonomic Nervous System Diseases; Orthostatic Intolerance; Cardiovascular Diseases; Primary Dysautonomias

  7. Advantages and disadvantages of stiffness instructions when studying postural control.

    PubMed

    Bonnet, Cédrick T

    2016-05-01

    To understand the maintenance of upright stance, researchers try to discover the fundamental mechanisms and attentional resources devoted to postural control and eventually to the performance of other tasks (e.g., counting in the head). During their studies, some researchers require participants to stand as steady as possible and other simply ask participants to stand naturally. Surprisingly, a clear and direct explanation of the usefulness of the steadiness requirement seems to be lacking, both in experimental and methodological discussions. Hence, the objective of the present note was to provide advantages and disadvantages of this steadiness requirement in studies of postural control. The advantages may be to study fundamental postural control, to eliminate useless postural variability, to control spurious body motions and to control the participants' thoughts. As disadvantages, this steadiness requirement only leads to study postural control in unnatural upright stance, it changes the focus of attention (internal vs. external) and the nature of postural control (unconscious vs. conscious), it increases the difficulty of a supposedly easy control task and it eliminates or reduces the opportunity to record exploratory behaviors. When looking carefully at the four advantages of the steadiness requirement, one can believe that they are, in fact, more disadvantageous than advantageous. Overall therefore, this requirement seems illegitimate and it is proposed that researchers should not use it in the study of postural control. They may use this requirement only if they search to know the limit until which participants can consciously reduce their postural sway.

  8. Tips to Maintain Good Posture

    MedlinePlus

    ... Pain and Chiropractic Posture Spinal Health Winter Activities Backpack Safety Kids and Sports Exercising Outdoors with Baby ... Pain and Chiropractic Posture Spinal Health Winter Activities Backpack Safety Kids and Sports Exercising Outdoors with Baby ...

  9. Body-Image Evaluation and Body-Image Investment among Adolescents: A Test of Sociocultural and Social Comparison Theories

    ERIC Educational Resources Information Center

    Morrison, Todd G.; Kalin, Rudolf; Morrison, Melanie A.

    2004-01-01

    Sociocultural theory and social comparison theory were used to account for variations in body-image evaluation and body-image investment among male and female adolescents (N = 1,543). Exposure to magazines and television programs containing idealistic body imagery as well as frequency of self-comparison to universalistic targets (e.g., fashion…

  10. Two-dimensional posture evaluation in Parkinson’s disease: effect of loads on the spinal angle during gait.

    NASA Astrophysics Data System (ADS)

    Celoria, Paula; Nanni, Federico; Pastore, Flavia; Pulenta, Sebastian; Tajerian, Matias; Pantazis, Lucio; Moscoso-Vasquez, Marcela; Cerquetti, Daniel; Merello, Marcelo; Risk, Marcelo

    2016-04-01

    Parkinson’s Disease patients present diminished coordination caused by neural degeneration. This leads to large motor difficulties during gait such as balance loss and pronounced forward inclination of the upper body. This work assessed the spinal sagittal plane angle alterations in two groups: six parkinsonian patients and six control healthy subjects. This parameter was analyzed during gait under three conditions: without external loads and with external loads applied either on the chest or on the lower back area. Results were statistically compared by means of t-test of paired samples in both groups. For patients, a significant effect was found when loads were applied on the chest. On the other hand, healthy subjects showed no significant differences in either case.

  11. Disordered eating links to body-relevant and body-irrelevant influences on self-evaluation.

    PubMed

    Woodward, Halley E; Rizk, Marianne T; Wang, Shirley S; Treat, Teresa A

    2014-04-01

    We investigated eating- and weight-related correlates of self-evaluation influences (SEIs) and examined the extent to which such SEIs can be both over- and undervalued and the extent to which measurement strategy affects SEIs. A female undergraduate sample (n = 549) completed 3 measures of SEI importance and questionnaires assessing disordered eating (DE), body mass index (BMI), and depression. SEI measures included Likert scale, rank ordering, and pairwise forced choice; a subset (n = 62) also completed the Shape- and Weight-Based Self-Esteem Scale (SAWBS). Only rank ordering, forced choice, and SAWBS constrain choices among SEIs, such that prioritizing one SEI necessarily deprioritizes another, which reflects real-world restrictions on individuals' allotment of time and energy (e.g., spending hours exercising daily necessarily reduces time available for other activities). By any measure, women with DE overvalue body shape and weight. The constraining measures reveal systematic undervaluation of intelligence and achievement among women with DE and an enhanced effect of DE on the overvaluation of weight and on the undervaluation of being a good person among those with higher BMI. Depressed women's self-evaluations overemphasize appearance and underemphasize interpersonal relationships. Self-evaluations of women with DE are marked by both over- and undervaluation of relevant SEIs; the overvaluation of shape and weight in DE may be associated with costs. Future use of constraining measures, such as forced choice or rank ordering, may enhance our understanding of both over- and underemphasized SEIs among women with DE. PMID:24854805

  12. Contribution of supraspinal systems to generation of automatic postural responses

    PubMed Central

    Deliagina, Tatiana G.; Beloozerova, Irina N.; Orlovsky, Grigori N.; Zelenin, Pavel V.

    2014-01-01

    Different species maintain a particular body orientation in space due to activity of the closed-loop postural control system. In this review we discuss the role of neurons of descending pathways in operation of this system as revealed in animal models of differing complexity: lower vertebrate (lamprey) and higher vertebrates (rabbit and cat). In the lamprey and quadruped mammals, the role of spinal and supraspinal mechanisms in the control of posture is different. In the lamprey, the system contains one closed-loop mechanism consisting of supraspino-spinal networks. Reticulospinal (RS) neurons play a key role in generation of postural corrections. Due to vestibular input, any deviation from the stabilized body orientation leads to activation of a specific population of RS neurons. Each of the neurons activates a specific motor synergy. Collectively, these neurons evoke the motor output necessary for the postural correction. In contrast to lampreys, postural corrections in quadrupeds are primarily based not on the vestibular input but on the somatosensory input from limb mechanoreceptors. The system contains two closed-loop mechanisms – spinal and spino-supraspinal networks, which supplement each other. Spinal networks receive somatosensory input from the limb signaling postural perturbations, and generate spinal postural limb reflexes. These reflexes are relatively weak, but in intact animals they are enhanced due to both tonic supraspinal drive and phasic supraspinal commands. Recent studies of these supraspinal influences are considered in this review. A hypothesis suggesting common principles of operation of the postural systems stabilizing body orientation in a particular plane in the lamprey and quadrupeds, that is interaction of antagonistic postural reflexes, is discussed. PMID:25324741

  13. "Stand up straight": notes toward a history of posture.

    PubMed

    Gilman, Sander L

    2014-03-01

    The essay presents a set of interlinked claims about posture in modern culture. Over the past two centuries it has come to define a wide range of assumptions in the West from what makes human beings human (from Lamarck to Darwin and beyond) to the efficacy of the body in warfare (from Dutch drill manuals in the 17th century to German military medical studies of soldiers in the 19th century). Dance and sport both are forms of posture training in terms of their own claims. Posture separates 'primitive' from 'advanced' peoples and the 'ill' from the 'healthy.' Indeed an entire medical sub-specialty developed in which gymnastics defined and recuperated the body. But all of these claims were also part of a Western attempt to use posture (and the means of altering it) as the litmus test for the healthy modern body of the perfect citizen. Focusing on the centrality of posture in two oddly linked moments of modern thought--modern Zionist thought and Nationalism in early 20th century China--in terms of bodily reform, we show how "posture" brings all of the earlier debates together to reform the body.

  14. "Stand up straight": notes toward a history of posture.

    PubMed

    Gilman, Sander L

    2014-03-01

    The essay presents a set of interlinked claims about posture in modern culture. Over the past two centuries it has come to define a wide range of assumptions in the West from what makes human beings human (from Lamarck to Darwin and beyond) to the efficacy of the body in warfare (from Dutch drill manuals in the 17th century to German military medical studies of soldiers in the 19th century). Dance and sport both are forms of posture training in terms of their own claims. Posture separates 'primitive' from 'advanced' peoples and the 'ill' from the 'healthy.' Indeed an entire medical sub-specialty developed in which gymnastics defined and recuperated the body. But all of these claims were also part of a Western attempt to use posture (and the means of altering it) as the litmus test for the healthy modern body of the perfect citizen. Focusing on the centrality of posture in two oddly linked moments of modern thought--modern Zionist thought and Nationalism in early 20th century China--in terms of bodily reform, we show how "posture" brings all of the earlier debates together to reform the body. PMID:24317755

  15. Falls study: Proprioception, postural stability, and slips.

    PubMed

    Sohn, Jeehoon; Kim, Sukwon

    2015-01-01

    The present study evaluated effects of exercise training on the proprioception sensitivity, postural stability, and the likelihood of slip-induced falls. Eighteen older adults (6 in balance, 6 in weight, and 6 in control groups) participated in this study. Three groups met three times per week over the course of eight weeks. Ankle and knee proprioception sensitivities and postural stability were measured. Slip-induced events were introduced for all participants before and after training. The results indicated that, overall, strength and postural stability were improved only in the training group, although proprioception sensitivity was improved in all groups. Training for older adults resulted in decreased likelihood of slip-induced falls. The study suggested that proprioception can be improved by simply being active, however, the results suggested that training would aid older adults in reducing the likelihood of slip-induced falls.

  16. Falls study: Proprioception, postural stability, and slips.

    PubMed

    Sohn, Jeehoon; Kim, Sukwon

    2015-01-01

    The present study evaluated effects of exercise training on the proprioception sensitivity, postural stability, and the likelihood of slip-induced falls. Eighteen older adults (6 in balance, 6 in weight, and 6 in control groups) participated in this study. Three groups met three times per week over the course of eight weeks. Ankle and knee proprioception sensitivities and postural stability were measured. Slip-induced events were introduced for all participants before and after training. The results indicated that, overall, strength and postural stability were improved only in the training group, although proprioception sensitivity was improved in all groups. Training for older adults resulted in decreased likelihood of slip-induced falls. The study suggested that proprioception can be improved by simply being active, however, the results suggested that training would aid older adults in reducing the likelihood of slip-induced falls. PMID:26406065

  17. Postural stability deficits during the transition from double-leg stance to single-leg stance in anterior cruciate ligament reconstructed subjects.

    PubMed

    Dingenen, Bart; Janssens, Luc; Claes, Steven; Bellemans, Johan; Staes, Filip F

    2015-06-01

    The goal of this study was to evaluate postural stability during the transition from double-leg stance (DLS) to single-leg stance (SLS) in anterior cruciate ligament reconstructed (ACLR) (n=20) and non-injured control subjects (n=20). All ACLR subjects had fully returned to their pre-injury sport participation. Both groups were similar for age, gender, height, weight, body mass index and activity level. Spatiotemporal center of pressure outcomes of both legs of each subject were measured during the transition from DLS to SLS in eyes open and eyes closed conditions. Movement speed was standardized. The center of pressure displacement after a new stability point was reached during the SLS phase was significantly increased in the ACLR group compared to the control group in the eyes closed condition (P=.001). No significant different postural stability outcomes were found between the operated and non-operated legs. In conclusion, the ACLR group showed postural stability deficits, indicating that these persons may have a decreased ability to stabilize their body after the internal postural perturbation created by the transition from DLS to SLS. The non-operated leg may not be the best reference when evaluating postural stability of the operated leg after ACLR, as no differences were found between legs.

  18. Postural orthostatic tachycardia syndrome.

    PubMed

    Agarwal, A K; Garg, R; Ritch, A; Sarkar, P

    2007-07-01

    Postural orthostatic tachycardia syndrome (POTS) is an autonomic disturbance which has become better understood in recent years. It is now thought to encompass a group of disorders that have similar clinical features, such as orthostatic intolerance, but individual distinguishing parameters--for example, blood pressure and pulse rate. The clinical picture, diagnosis, and management of POTS are discussed.

  19. Posture and Movement

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Session TP3 includes short reports on: (1) Modification of Goal-Directed Arm Movements During Inflight Adaptation to Microgravity; (2) Quantitative Analysis of Motion control in Long Term Microgravity; (3) Does the Centre of Gravity Remain the Stabilised Reference during Complex Human Postural Equilibrium Tasks in Weightlessness?; and (4) Arm End-Point Trajectories Under Normal and Microgravity Environments.

  20. The force output of handle and pedal in different bicycle-riding postures.

    PubMed

    Chen, Chia-Hsiang; Wu, Yu-Kuang; Chan, Ming-Sheng; Shih, Yo; Shiang, Tzyy-Yuang

    2016-01-01

    The purpose of this study was to analyse the force output of handle and pedal as well as the electromyography (EMG) of lower extremity in different cycling postures. Bilateral pedalling asymmetry indices of force and EMG were also determined in this study. Twelve healthy cyclists were recruited for this study and tested for force output and EMG during steady state cycling adopting different pedalling and handle bar postures. The standing posture increased the maximal stepping torque (posture 1: 204.2 ± 47.0 Nm; posture 2: 212.5 ± 46.1 Nm; posture 3: 561.5 ± 143.0 Nm; posture 4: 585.5 ± 139.1 Nm), stepping work (posture 1: 655.2 ± 134.6 Nm; posture 2: 673.2 ± 116.3 Nm; posture 3: 1852.3 ± 394.4 Nm; posture 4: 1911.3 ± 432.9 Nm), and handle force (posture 1: 16.6 ± 3.6 N; posture 2: 16.4 ± 3.6 N; posture 3: 26.5 ± 8.2 N; posture 4: 41.4 ± 11.1 N), as well as muscle activation (posture 1: 13.6-25.1%; posture 2: 13.0-23.9%; posture 3: 23.6-61.8%; posture 4: 22.5-65.8%) in the erector spine, rectus femoris, tibialis anterior, and soleus. However, neither a sitting nor a standing riding posture affected the hamstring. The riding asymmetry was detected between the right and left legs only in sitting conditions. When a cyclist changes posture from sitting to standing, the upper and lower extremities are forced to produce more force output because of the shift in body weight. These findings suggest that cyclists can switch between sitting and standing postures during competition to increase cycling efficiency in different situations. Furthermore, coaches and trainers can modify sitting and standing durations to moderate cycling intensity, without concerning unbalanced muscle development. PMID:26967311

  1. Action recognition by motion detection in posture space.

    PubMed

    Theusner, Stefanie; de Lussanet, Marc; Lappe, Markus

    2014-01-15

    The visual recognition of action can be obtained from the change of body posture over time. Even for point-light stimuli in which the body posture is conveyed by only a few light points, biological motion can be perceived from posture sequence analysis. We present and analyze a formal model of how action recognition may be computed and represented in the brain. This model assumes that motion energy detectors similar to those well-established for the luminance-based motion of objects in space are applied to a cortical representation of body posture. Similar to the spatio-temporal receptive fields of regular motion detectors, these body motion detectors attain receptive fields in a posture-time space. We describe the properties of these receptive fields and compare them with properties of body-sensitive neurons found in the superior temporal sulcus of macaque monkeys. We consider tuning properties for 3D views of static and moving bodies. Our simulations show that key properties of action representation in the STS can directly be explained from the properties of natural action stimuli. Our model also suggests an explanation for the phenomenon of implied motion, the perceptual appearance, and neural activation of motion from static images. PMID:24431449

  2. The Know Your Body program: a review of evaluation studies.

    PubMed Central

    Resnicow, K.; Cross, D.; Wynder, E.

    1993-01-01

    Know Your Body is a comprehensive school health promotion program for kindergarten through six grades, initially developed in the 1970s by the American Health Foundation. The impact of the KYB program has been evaluated in three field trials, the results of which have been reviewed in this article. Across the three studies, at 3-year follow-up, consistent positive intervention effects were reported for systolic blood pressure, diastolic blood pressure, smoking, HDL-cholesterol, and health knowledge. Results for total blood cholesterol, fitness score, heart-healthy snacks, fruit/vegetable intake, whole milk intake, and health attitudes were mixed. For body mass index, triceps skinfold, all remaining dietary variables, self-esteem/self-efficacy, and locus of control no significant effects were observed. Overall, significant treatment effects were reported for 19 of the 40 variables assessed at 3-year follow-up, an effects ratio of 48%. Consistent positive results at 5-year follow-up were reported for smoking and health knowledge. Mixed results were obtained for total blood cholesterol, diastolic blood pressure, and percent kilocalories from saturated fat. Consistent null results were reported for HDL-cholesterol, systolic blood pressure, body mass index, triceps skinfold, fitness score, percentage kilocalories from fat, cholesterol intake, and fiber intake. Overall, significant treatment effects were reported for 7 of 36 variables at 5-year follow-up, an effects ratio of 19%. Although reported program effects were largely mixed, they seem consistent with other health education evaluations. Null results may have been related to insufficient teacher implementation as well as weaknesses in design and assessment. Additional research is needed to determine the effect of the program on a broader range of outcomes, to what degree increasing the "dose" produces larger and more enduring treatment effects, and the relative impact of the various components that comprise the

  3. Ankle and hip postural strategies defined by joint torques.

    PubMed

    Runge, C F; Shupert, C L; Horak, F B; Zajac, F E

    1999-10-01

    Previous studies have identified two discrete strategies for the control of posture in the sagittal plane based on EMG activations, body kinematics, and ground reaction forces. The ankle strategy was characterized by body sway resembling a single-segment-inverted pendulum and was elicited on flat support surfaces. In contrast, the hip strategy was characterized by body sway resembling a double-segment inverted pendulum divided at the hip and was elicited on short or compliant support surfaces. However, biomechanical optimization models have suggested that hip strategy should be observed in response to fast translations on a flat surface also, provided the feet are constrained to remain in contact with the floor and the knee is constrained to remain straight. The purpose of this study was to examine the experimental evidence for hip strategy in postural responses to backward translations of a flat support surface and to determine whether analyses of joint torques would provide evidence for two separate postural strategies. Normal subjects standing on a flat support surface were translated backward with a range of velocities from fast (55 cm/s) to slow (5 cm/s). EMG activations and joint kinematics showed pattern changes consistent with previous experimental descriptions of mixed hip and ankle strategy with increasing platform velocity. Joint torque analyses revealed the addition of a hip flexor torque to the ankle plantarflexor torque during fast translations. This finding indicates the addition of hip strategy to ankle strategy to produce a continuum of postural responses. Hip torque without accompanying ankle torque (pure hip strategy) was not observed. Although postural control strategies have previously been defined by how the body moves, we conclude that joint torques, which indicate how body movements are produced, are useful in defining postural control strategies. These results also illustrate how the biomechanics of the body can transform discrete control

  4. Ankle and hip postural strategies defined by joint torques

    NASA Technical Reports Server (NTRS)

    Runge, C. F.; Shupert, C. L.; Horak, F. B.; Zajac, F. E.; Peterson, B. W. (Principal Investigator)

    1999-01-01

    Previous studies have identified two discrete strategies for the control of posture in the sagittal plane based on EMG activations, body kinematics, and ground reaction forces. The ankle strategy was characterized by body sway resembling a single-segment-inverted pendulum and was elicited on flat support surfaces. In contrast, the hip strategy was characterized by body sway resembling a double-segment inverted pendulum divided at the hip and was elicited on short or compliant support surfaces. However, biomechanical optimization models have suggested that hip strategy should be observed in response to fast translations on a flat surface also, provided the feet are constrained to remain in contact with the floor and the knee is constrained to remain straight. The purpose of this study was to examine the experimental evidence for hip strategy in postural responses to backward translations of a flat support surface and to determine whether analyses of joint torques would provide evidence for two separate postural strategies. Normal subjects standing on a flat support surface were translated backward with a range of velocities from fast (55 cm/s) to slow (5 cm/s). EMG activations and joint kinematics showed pattern changes consistent with previous experimental descriptions of mixed hip and ankle strategy with increasing platform velocity. Joint torque analyses revealed the addition of a hip flexor torque to the ankle plantarflexor torque during fast translations. This finding indicates the addition of hip strategy to ankle strategy to produce a continuum of postural responses. Hip torque without accompanying ankle torque (pure hip strategy) was not observed. Although postural control strategies have previously been defined by how the body moves, we conclude that joint torques, which indicate how body movements are produced, are useful in defining postural control strategies. These results also illustrate how the biomechanics of the body can transform discrete control

  5. Effect of absence of vision on posture

    PubMed Central

    Alotaibi, Abdullah Z.; Alghadir, Ahmad; Iqbal, Zaheen A.; Anwer, Shahnawaz

    2016-01-01

    [Purpose] The visual system is one of the sensory systems that enables the body to assess and process information about the external environment. In the absence of vision, a blind person loses contact with the outside world and develops faulty motor patterns, which results in postural deficiencies. However, literature regarding the development of such deficiencies is limited. The aim of this study was to discuss the effect of absence of vision on posture, the possible biomechanics behind the resulting postural deficiencies, and strategies to correct and prevent them. [Subjects and Methods] Various electronic databases including PubMed, Medline, and Google scholar were examined using the words “body”, “posture”, “blind” and “absence of vision”. References in the retrieved articles were also examined for cross-references. The search was limited to articles in the English language. [Results] A total of 74 papers were shortlisted for this review, most of which dated back to the 1950s and 60s. [Conclusion] Blind people exhibit consistent musculoskeletal deformities. Absence of vision leads to numerous abnormal sensory and motor interactions that often limit blind people in isolation. Rehabilitation of the blind is a multidisciplinary task. Specialists from different fields need to diagnose and treat the deficiencies of the blind together as a team. Before restoring the normal mechanics of posture and gait, the missing link with the external world should be reestablished. PMID:27190486

  6. Fluence-to-dose conversion coefficients based on the posture modification of Adult Male (AM) and Adult Female (AF) reference phantoms of ICRP 110

    NASA Astrophysics Data System (ADS)

    Galeano, D. C.; Santos, W. S.; Alves, M. C.; Souza, D. N.; Carvalho, A. B.

    2016-04-01

    The aim of this work was to modify the standing posture of the anthropomorphic reference phantoms of ICRP publication 110, AM (Adult Male) and AF (Adult Female), to the sitting posture. The change of posture was performed using the Visual Monte Carlo software (VMC) to rotate the thigh region of the phantoms and position it between the region of the leg and trunk. Scion Image software was used to reconstruct and smooth the knee and hip contours of the phantoms in a sitting posture. For 3D visualization of phantoms, the VolView software was used. In the change of postures, the organ and tissue masses were preserved. The MCNPX was used to calculate the equivalent and effective dose conversion coefficients (CCs) per fluence for photons for six irradiation geometries suggested by ICRP publication 110 (AP, PA, RLAT, LLAT, ROT and ISO) and energy range 0.010-10 MeV. The results were compared between the standing and sitting postures, for both sexes, in order to evaluate the differences of scattering and absorption of radiation for different postures. Significant differences in the CCs for equivalent dose were observed in the gonads, colon, prostate, urinary bladder and uterus, which are present in the pelvic region, and in organs distributed throughout the body, such as the lymphatic nodes, muscle, skeleton and skin, for the phantoms of both sexes. CCs for effective dose showed significant differences of up to 16% in the AP irradiation geometry, 27% in the PA irradiation geometry and 13% in the ROT irradiation geometry. These results demonstrate the importance of using phantoms in different postures in order to obtain more precise conversion coefficients for a given exposure scenario.

  7. Postural control during kneeling.

    PubMed

    Mezzarane, Rinaldo André; Kohn, André Fabio

    2008-05-01

    Postural control was studied when the subject was kneeling with erect trunk in a quiet posture and compared to that obtained during quiet standing. The analysis was based on the center of pressure motion in the sagittal plane (CPx), both in the time and in the frequency domains. One could assume that postural control during kneeling would be poorer than in standing because it is a less natural posture. This could cause a higher CPx variability. The power spectral density (PSD) of the CPx obtained from the experimental data in the kneeling position (KN) showed a significant decrease at frequencies below 0.3 Hz compared to upright (UP) (P < 0.01), which indicates less sway in KN. Conversely, there was an increase in fast postural oscillations (above 0.7 Hz) during KN compared to UP (P < 0.05). The root mean square (RMS) of the CPx was higher for UP (P < 0.01) while the mean velocity (MV) was higher during KN (P < 0.05). Lack of vision had a significant effect on the PSD and the parameters estimated from the CPx in both positions. We also sought to verify whether the changes in the PSD of the CPx found between the UP and KN positions were exclusively due to biomechanical factors (e.g., lowered center of gravity), or also reflected changes in the neural processes involved in the control of balance. To reach this goal, besides the experimental approach, a simple feedback model (a PID neural system, with added neural noise and controlling an inverted pendulum) was used to simulate postural sway in both conditions (in KN the pendulum was shortened, the mass and the moment of inertia were decreased). A parameter optimization method was used to fit the CPx power spectrum given by the model to that obtained experimentally. The results indicated that the changed anthropometric parameters in KN would indeed cause a large decrease in the power spectrum at low frequencies. However, the model fitting also showed that there were considerable changes also in the neural subsystem

  8. Body inversion effect without body sense: insights from deafferentation.

    PubMed

    Bosbach, Simone; Knoblich, Guenther; Reed, Catherine L; Cole, Jonathan; Prinz, Wolfgang

    2006-01-01

    Like faces, human bodies are recognized via the configuration of their parts; their recognition is impaired by inversion. Processing of configural relations has been shown to depend on perceptual expertise with certain classes of objects. Because people see their own body and others' bodies frequently, humans are experts in the visual processing of human body postures. In addition, the observer's own on-line, multimodal body representation which heavily relies on current proprioception may play a crucial role in recognizing human body postures. We investigated whether static body posture recognition relied on current proprioceptive inputs or whether visual familiarity and stored body representations were sufficient. IW, who is deafferented (lost cutaneous touch and proprioception from his body), was tested on the recognition of upright and inverted human body postures, faces, and houses. As controls, IW showed an inversion effect for abstract, common, and rare human body postures as well as faces, but not houses. Results rule out a strong contribution of current afferent inputs to the recognition of human postures. The findings are discussed in terms of the role of the body schema in body posture recognition and how other contributions from one's own body may be involved in the visual processing of human bodies.

  9. On the Health Risk of the Lumbar Spine due to Whole-Body VIBRATION—THEORETICAL Approach, Experimental Data and Evaluation of Whole-Body Vibration

    NASA Astrophysics Data System (ADS)

    Seidel, H.; Blüthner, R.; Hinz, B.; Schust, M.

    1998-08-01

    The guidance on the effects of vibration on health in standards for whole-body vibration (WBV) does not provide quantitative relationships between WBV and health risk. The paper aims at the elucidation of exposure-response relationships. An analysis of published data on the static and dynamic strength of vertebrae and bone, loaded with various frequencies under different conditions, provided the basis for a theoretical approach to evaluate repetitive loads on the lumbar spine (“internal loads”). The approach enabled the calculation of “equivalent”—with respect to cumulative fatigue failure—combinations of amplitudes and numbers of internal cyclic stress. In order to discover the relation between external peak accelerations at the seat and internal peak loads, biodynamic data of experiments (36 subjects, three somatotypes, two different postures—relaxed and bent forward; random WBV,aw, r.m.s. 1·4 ms-2, containing high transients) were used as input to a biomechanical model. Internal pressure changes were calculated using individual areas of vertebral endplates. The assessment of WBV was based on the quantitative relations between peak accelerations at the seat and pressures predicted for the disk L5/S1. For identical exposures clearly higher rates of pressure rise in the bent forward compared to the relaxed posture were predicted. The risk assessment for internal forces considered the combined internal static and dynamic loads, in relation to the predicted individual strength, and Miner's hypothesis. For exposure durations between 1 min and 8 h, energy equivalent vibration magnitudes (formula B.1, ISO 2631-1, 1997) and equivalent vibration magnitudes according to formula B.2 (time dependence over-energetic) were compared with equivalent combinations of upward peak accelerations and exposure durations according to predicted cumulative fatigue failures of lumbar vertebrae. Formula B.1 seems to underestimate the health risk caused by high magnitudes

  10. The Effect of Breast Hypertrophy on Patient Posture

    PubMed Central

    de Groof, E Joline; Corion, Leonard UMC; Smeulders, Mark JC; van der Horst, Chantal MAM

    2013-01-01

    Background One of the reasons women with macromastia chose to undergo a breast reduction is to relieve their complaints of back, neck, and shoulder pain. We hypothesized that changes in posture after surgery may be the reason for the pain relief and that patient posture may correlate with symptomatic macromastia and may serve as an objective measure for complaints. The purpose of our study was to evaluate the effect of reduction mammaplasty on the posture of women with macromastia. Methods A prospective controlled study at a university medical center. Forty-two patients that underwent breast reduction were studied before surgery and an average of 4.3 years following surgery. Thirty-seven healthy women served as controls. Standardized lateral photos were taken. The inclination angle of the back was measured. Regression analysis was performed for the inclination angle. Results Preoperatively, the mean inclination angle was 1.61 degrees ventrally; this diminished postoperatively to 0.72 degrees ventrally. This change was not significant (P-value=0.104). In the control group that angle was 0.28 degrees dorsally. Univariate regression analysis revealed that the inclination was dependent on body mass index (BMI) and having symptomatic macromastia; on multiple regression it was only dependent on BMI. Conclusions The inclination angle of the back in breast reduction candidates is significantly different from that of controls; however, this difference is small and probably does not account for the symptoms associated with macromastia. Back inclination should not be used as a surrogate "objective" measure for symptomatic macromastia. PMID:24086810

  11. Craniocervical Posture in Patients with Obstructive Sleep Apnea

    PubMed Central

    Piccin, Chaiane Facco; Pozzebon, Daniela; Scapini, Fabricio; Corrêa, Eliane Castilhos Rodrigues

    2016-01-01

    Introduction  Obstructive Sleep Apnea (OSA) is characterized by repeated episodes of upper airway obstruction during sleep. Objective  The objective of this study is to verify the craniofacial characteristics and craniocervical posture of OSA and healthy subjects, determining possible relationships with the apnea/hypopnea index (AHI). Methods  This case-control study evaluated 21 subjects with OSA, who comprised the OSA group (OSAG), and 21 healthy subjects, who constituted the control group (CG). Cephalometry analyzed head posture measurements, craniofacial measurements, and air space. Head posture was also assessed by means of photogrammetry. Results  The groups were homogeneous regarding gender (12 men and 9 women in each group), age (OSAG = 41.86 ± 11.26 years; GC = 41.19 ± 11.20 years), and body mass index (OSAG = 25.65 ± 2.46 kg/m2; CG = 24.72 ± 3.01 kg/m2). We found significant differences between the groups, with lower average pharyngeal space and greater distance between the hyoid bone and the mandibular plane in OSAG, when compared with CG. A positive correlation was found between higher head hyperextension and head anteriorization, with greater severity of OSA as assessed by AHI. Conclusion  OSAG subjects showed changes in craniofacial morphology, with lower average pharyngeal space and greater distance from the hyoid bone to the mandibular plane, as compared with healthy subjects. Moreover, in OSA subjects, the greater the severity of OSA, the greater the head hyperextension and anteriorization. PMID:27413397

  12. [Psychometric evaluation of the Body Change Questionnaire for adolescents].

    PubMed

    Meireles, Juliana Fernandes Filgueiras; Amaral, Ana Carolina Soares; Neves, Clara Mockdece; Conti, Maria Aparecida; Ferreira, Maria Elisa Caputo

    2015-11-01

    This study aimed to examine construct validity, internal consistency, and reproducibility of the Body Change Questionnaire (BCQ). A total of 439 female and male adolescents (13-22 years of age) were evaluated. Construct validity was assessed by exploratory factor analysis and correlation between the scores of the BCQ and the Body Shape Questionnaire (BSQ) and Scale Silhouettes (SS). Reliability was assessed through internal consistency and reproducibility using test-retest and intra-class correlation. The scale presented a six-factor structure that almost entirely accounted for the instrument's subscales. Correlations for the total sample between BCQ and scores of the other questionnaires ranged from 0.37 to 0.46. Internal consistency varied from 0.78 to 0.96 for each of the factors, and intra-class correlation was consistent with good reproducibility. The test-retest scores showed no statistically significant differences for the total sample or according to sex. The BCQ showed good psychometric qualities for Brazilian adolescents. PMID:26840810

  13. Arterial Pressure Gradients during Upright Posture and 30 deg Head Down Tilt

    NASA Technical Reports Server (NTRS)

    Sanchez, E. R; William, J. M.; Ueno, T.; Ballard, R. E.; Hargens, A. R.; Holton, Emily M. (Technical Monitor)

    1997-01-01

    Gravity alters local blood pressure within the body so that arterial pressures in the head and foot are lower and higher, respectively, than that at heart level. Furthermore, vascular responses to local alterations of arterial pressure are probably important to maintain orthostatic tolerance upon return to the Earth after space flight. However, it has been difficult to evaluate the body's arterial pressure gradient due to the lack of noninvasive technology. This study was therefore designed to investigate whether finger arterial pressure (FAP), measured noninvasively, follows a normal hydrostatic pressure gradient above and below heart level during upright posture and 30 deg head down tilt (HDT). Seven healthy subjects gave informed consent and were 19 to 52 years old with a height range of 158 to 181 cm. A Finapres device measured arterial pressure at different levels of the body by moving the hand from 36 cm below heart level (BH) to 72 cm above heart level (AH) in upright posture and from 36 cm BH to 48 cm AH during HDT in increments of 12 cm. Mean FAP creased by 85 mmHg transitioning from BH to AH in upright posture, and the pressure gradient calculated from hydrostatic pressure difference (rho(gh)) was 84 mmHg. In HDT, mean FAP decreased by 65 mmHg from BH to AH, and the calculated pressure gradient was also 65 mmHg. There was no significant difference between the measured FAP gradient and the calculated pressure gradient, although a significant (p = 0.023) offset was seen for absolute arterial pressure in upright posture. These results indicate that arterial pressure at various levels can be obtained from the blood pressure at heart level by calculating rho(gh) + an offset. The offset equals the difference between heart level and the site of measurement. In summary, we conclude that local blood pressure gradients can be measured by noninvasive studies of FAP.

  14. Stand Up Straight: Posture for Singers.

    ERIC Educational Resources Information Center

    Gauthier, Delores R.

    2002-01-01

    Focuses on the importance of posture in music-making. Provides information on the importance of posture and the different types of posture stances to help students work toward better posture. Includes information on using kinesthetic experiences to help students improve their posture. (CMK)

  15. Adaptability of anticipatory postural adjustments associated with voluntary movement

    PubMed Central

    Yiou, Eric; Caderby, Teddy; Hussein, Tarek

    2012-01-01

    The control of balance is crucial for efficiently performing most of our daily motor tasks, such as those involving goal-directed arm movements or whole body displacement. The purpose of this article is twofold. Firstly, it is to recall how balance can be maintained despite the different sources of postural perturbation arising during voluntary movement. The importance of the so-called “anticipatory postural adjustments” (APA), taken as a “line of defence” against the destabilizing effect induced by a predicted perturbation, is emphasized. Secondly, it is to report the results of recent studies that questioned the adaptability of APA to various constraints imposed on the postural system. The postural constraints envisaged here are classified into biomechanical (postural stability, superimposition of motor tasks), (neuro) physiological (fatigue), temporal (time pressure) and psychological (fear of falling, emotion). Overall, the results of these studies point out the capacity of the central nervous system (CNS) to adapt the spatio-temporal features of APA to each of these constraints. However, it seems that, depending on the constraint, the “priority” of the CNS was focused on postural stability maintenance, on body protection and/or on maintenance of focal movement performance. PMID:22720267

  16. Evidence from the eyes: Threatening postures hold attention.

    PubMed

    Azarian, Bobby; Esser, Elizabeth G; Peterson, Matthew S

    2016-06-01

    Efficient detection of threat provides obvious survival advantages and has resulted in a fast and accurate threat-detection system. Although beneficial under normal circumstances, this system may become hypersensitive and cause threat-processing abnormalities. Past research has shown that anxious individuals have difficulty disengaging attention from threatening faces, but it is unknown whether other forms of threatening social stimuli also influence attentional orienting. Much like faces, human body postures are salient social stimuli, because they are informative of one's emotional state and next likely action. Additionally, postures can convey such information in situations in which another's facial expression is not easily visible. Here we investigated whether there is a threat-specific effect for high-anxious individuals, by measuring the time that it takes the eyes to leave the attended stimulus, a task-irrelevant body posture. The results showed that relative to nonthreating postures, threat-related postures hold attention in anxious individuals, providing further evidence of an anxiety-related attentional bias for threatening information. This is the first study to demonstrate that attentional disengagement from threatening postures is affected by emotional valence in those reporting anxiety.

  17. Otolith and Vertical Canal Contributions to Dynamic Postural Control

    NASA Technical Reports Server (NTRS)

    Black, F. Owen

    1999-01-01

    The objective of this project is to determine: 1) how do normal subjects adjust postural movements in response to changing or altered otolith input, for example, due to aging? and 2) how do patients adapt postural control after altered unilateral or bilateral vestibular sensory inputs such as ablative inner ear surgery or ototoxicity, respectively? The following hypotheses are under investigation: 1) selective alteration of otolith input or abnormalities of otolith receptor function will result in distinctive spatial, frequency, and temporal patterns of head movements and body postural sway dynamics. 2) subjects with reduced, altered, or absent vertical semicircular canal receptor sensitivity but normal otolith receptor function or vice versa, should show predictable alterations of body and head movement strategies essential for the control of postural sway and movement. The effect of altered postural movement control upon compensation and/or adaptation will be determined. These experiments provide data for the development of computational models of postural control in normals, vestibular deficient subjects and normal humans exposed to unusual force environments, including orbital space flight.

  18. Abnormal postural reflexes in a patient with pontine ischaemia.

    PubMed

    Cantello, Roberto; Magistrelli, Luca; Terazzi, Emanuela; Grossini, Elena

    2015-01-01

    The control of body posture is a complex activity that needs a very close relationship between different structures, such as the vestibular system, and the muscle and joint receptors of the neck. Damage of even one of these structures can lead to abnormal postural reflexes. We describe a case of a woman with a left pontine ischaemia who developed a 'dystonic' extensor posture of the left limbs while turned on the right side. This clinical picture differs from previous reports on the subject, and may relate to ischaemic damage of a pontine structure involved in posture control, or of adjacent neural connections to be yet identified. To the best of our knowledge, this is the first case reported in the literature. Clinical examples of an altered interplay between vestibular and neck receptors are rare. PMID:26561222

  19. A quantitative measurement method for comparison of seated postures.

    PubMed

    Hillman, Susan J; Hollington, James

    2016-05-01

    This technical note proposes a method to measure and compare seated postures. The three-dimensional locations of palpable anatomical landmarks corresponding to the anterior superior iliac spines, clavicular notch, head, shoulders and knees are measured in terms of x, y and z co-ordinates in the reference system of the measuring apparatus. These co-ordinates are then transformed onto a body-based axis system which allows comparison within-subject. The method was tested on eleven unimpaired adult participants and the resulting data used to calculate a Least Significant Difference (LSD) for the measure, which is used to determine whether two postures are significantly different from one another. The method was found to be sensitive to the four following standardised static postural perturbations: posterior pelvic tilt, pelvic obliquity, pelvic rotation, and abduction of the thighs. The resulting data could be used as an outcome measure for the postural alignment aspect of seating interventions in wheelchairs. PMID:26920073

  20. Posture of patients with sleep apnea during sleep.

    PubMed

    Akita, Yasutaka; Kawakatsu, Kenji; Hattori, Chikaya; Hattori, Hirokazu; Suzuki, Kenji; Nishimura, Tadao

    2003-01-01

    The relationship between sleep apnea syndrome (SAS) and posture during sleep has been noted and the beneficial effect of an optimal posture on sleep apnea has been empirically indicated. We investigated this effect in a group of subjects that included obese patients and found that the apnea-hypopnea index (AHI) may be normalized in the lateral position, even among patients severely affected with apnea. Among those with intermediate or lower AHI values sleeping in a lateral position markedly improved the symptoms, with AHI even approaching the normal range in many patients. A tendency was noted for AHI to rise regardless of posture but in proportion to the increase in body mass index (BMI). In other words, the improvement due to changes in posture became increasingly insignificant with increase in BMI.

  1. Correcting working postures in industry: A practical method for analysis.

    PubMed

    Karhu, O; Kansi, P; Kuorinka, I

    1977-12-01

    A practical method for identifying and evaluating poor working postures, ie, the Ovako Working Posture Analysing System (OWAS), is presented. The method consists of two parts. The first is an observational technique for evaluating working postures. It can be used by work-study engineers in their daily routine and it gives reliable results after a short training period. The second part of the method is a set of criteria for the redesign of working methods and places. The criteria are based on evaluations made by experienced workers and ergonomics experts. They take into consideration factors such as health and safety, but the main emphasis is placed on the discomfort caused by the working postures. The method has been extensively used in the steel company which participated in its development. Complete production lines have already been redesigned on the basis of information gathered from OWAS, the result being more comfortable workplaces as well as a positive effect on production quality.

  2. Cuttlefish use visual cues to determine arm postures for camouflage

    PubMed Central

    Barbosa, Alexandra; Allen, Justine J.; Mäthger, Lydia M.; Hanlon, Roger T.

    2012-01-01

    To achieve effective visual camouflage, prey organisms must combine cryptic coloration with the appropriate posture and behaviour to render them difficult to be detected or recognized. Body patterning has been studied in various taxa, yet body postures and their implementation on different backgrounds have seldom been studied experimentally. Here, we provide the first experimental evidence that cuttlefish (Sepia officinalis), masters of rapid adaptive camouflage, use visual cues from adjacent visual stimuli to control arm postures. Cuttlefish were presented with a square wave stimulus (period = 0.47 cm; black and white stripes) that was angled 0°, 45° or 90° relative to the animals' horizontal body axis. Cuttlefish positioned their arms parallel, obliquely or transversely to their body axis according to the orientation of the stripes. These experimental results corroborate our field observations of cuttlefish camouflage behaviour in which flexible, precise arm posture is often tailored to match nearby objects. By relating the cuttlefishes' visual perception of backgrounds to their versatile postural behaviour, our results highlight yet another of the many flexible and adaptive anti-predator tactics adopted by cephalopods. PMID:21561967

  3. Can osteopathic manipulative treatment modify the posture in elderly people? - a single-case study.

    PubMed

    Pellerin, F; Papin-Richard, E; Guihéneuc, P; Niel, S; Guihard, G

    2015-04-01

    In this research, we have studied the consequences of three consecutive osteopathic manipulative sessions (OMS) on postural control by using a single-case research (SCR) design. The patient was a 77 years old woman complaining of altered balance and low-back pain. OMS were delivered by a single practitioner. The pain level was self-rated by using a visual Borg scale. The posture was monitored on a force platform. Postural parameters were deduced from the analysis of the centre of foot pressure (CoP) displacement. The statistical significance of the observed differences was established by using an SCR-related effect size indicator (i.e. Taunovlap). Our results indicate that OMS decrease the patient's pain, modify CoP mean position and decreased the length and velocity of the CoP displacement. Furthermore, modifications of the body oscillations were observed after OMS. This work indicates that OMS can improve body balance and that SCR allows the objective evaluation of the consequences of OMS.

  4. Coordination between posture and movement: interaction between postural and accuracy constraints.

    PubMed

    Berrigan, Félix; Simoneau, Martin; Martin, Olivier; Teasdale, Normand

    2006-04-01

    We examined the interaction between the control of posture and an aiming movement. Balance control was varied by having subjects aim at a target from a seated or a standing position. The aiming difficulty was varied using a Fitts'-like paradigm (movement amplitude=30 cm; target widths=0.5, 1.0, 2.5 and 5 cm). For both postural conditions, all targets were within the reaching space in front of the subjects and kept at a fixed relative position with respect to the subjects' body. Hence, for a given target size, the aiming was differentiated only by the postural context (seated vs. upright standing). For both postural conditions, movement time (MT) followed the well-known Fitts' law, that is, it increased with a decreasing target size. For the smallest target width, however, the increased MT was greater when subjects were standing than when they were seated suggesting that the difficulty of the aiming task could not be determined solely by the target size. When standing, a coordination between the trunk and the arm was observed. Also, as the target size decreased, the center of pressure (CP) displacement increased without any increase in CP speed suggesting that the subjects were regulating their CP to provide a controlled referential to assist the hand movement. When seated, the CP kinematics was scaled with the hand movement kinematics. Increasing the index of difficulty led to a strong correlation between the hand speed and CP displacement and speed. The complex organization between posture and movement was revealed only by examining the specific interactions between speed-accuracy and postural constraints. PMID:16328274

  5. MRI Evaluation of Spinal Length and Vertebral Body Angle During Loading with a Spinal Compression Harness

    NASA Technical Reports Server (NTRS)

    Campbell, James A.; Hargens, Alan R.; Murthy, G.; Ballard, R. E.; Watenpaugh, D. E.; Hargens, Alan, R.; Sanchez, E.; Yang, C.; Mitsui, I.; Schwandt, D.; Fechner, K. P.; Holton, Emily M. (Technical Monitor)

    1998-01-01

    Weight bearing by the spinal column during upright posture often plays a role in the common problem of low back pain. Therefore, we developed a non-ferromagnetic spinal compression harness to enable MRI investigations of the spinal column during axial loading. Human subjects were fitted with a Nest and a footplate which were connected by adjustable straps to an analog load cell. MRI scans of human subjects (5 males and 1 female with age range of 27-53 yrs) during loaded and unloaded conditions were accomplished with a 1.5 Tesla GE Signa scanner. Studies of two subjects undergoing sequentially increasing spinal loads revealed significant decreases (r(sup 2) = 0.852) in spinal length between T4 and L5 culminating in a 1.5 to 2% length decrease during loading with 75% body weight. Sagittal vertebral body angles of four subjects placed under a constant 50% body weight load for one hour demonstrated increased lordotic and kyphotic curvatures. In the lumbar spine, the L2 vertebral body experienced the greatest angular change (-3 deg. to -5 deg.) in most subjects while in the thoracic spine, T4 angles increased from the unloaded state by +2 deg. to +9 deg. Overall, our studies demonstrate: 1) a progressive, although surprisingly small, decrease in spinal length with increasing load and 2) relatively large changes in spinal column angulation with 50% body weight.

  6. Postural control during pushing movement with risk of forward perturbation.

    PubMed

    Okai, Rika; Fujiwara, Motoko

    2013-06-01

    The purpose of this study was to investigate the effect of a forward bilateral pushing movement on postural control in a situation where known, unknown, and unpredictable perturbations may be induced. Participants stood upright and voluntarily pushed a handle with both hands. In the first task, the handle was free to be moved by the participant (perturbation; movable task) and in the second task, the handle was locked (stationary task). For each task, body displacement and observed applied force were recorded. Anticipatory postural control adjustment plays a vital role in body stability; however, in contrast to its role in maintaining stability, adjustment can generate a restricted voluntary movement because motor programming selects a postural control that gives priority to body stability over the target movement.

  7. Tai Chi training reduced coupling between respiration and postural control.

    PubMed

    Holmes, Matthew L; Manor, Brad; Hsieh, Wan-hsin; Hu, Kun; Lipsitz, Lewis A; Li, Li

    2016-01-01

    In order to maintain stable upright stance, the postural control system must account for the continuous perturbations to the body's center-of-mass including those caused by spontaneous respiration. Both aging and disease increase "posturo-respiratory synchronization;" which reflects the degree to which respiration affects postural sway fluctuations over time. Tai Chi training emphasizes the coordination of respiration and bodily movements and may therefore optimize the functional interaction between these two systems. The purpose of the project was to examine the effect of Tai Chi training on the interaction between respiration and postural control in older adults. We hypothesized that Tai Chi training would improve the ability of the postural control system to compensate for respiratory perturbations and thus, reduce posturo-respiratory synchronization. Participants were recruited from supportive housing facilities and randomized to a 12-week Tai Chi intervention (n=28; 86 ± 5 yrs) or educational-control program (n=34, 85 ± 6 yrs). Standing postural sway and respiration were simultaneously recorded with a force plate and respiratory belt under eyes-open and eyes-closed conditions. Posturo-respiratory synchronization was determined by quantifying the variation of the phase relationship between the dominant oscillatory mode of respiration and corresponding oscillations within postural sway. Groups were similar in age, gender distribution, height, body mass, and intervention compliance. Neither intervention altered average sway speed, sway magnitude or respiratory rate. As compared to the education-control group, however, Tai Chi training reduced posturo-respiratory synchronization when standing with eyes open or closed (p<0.001). Tai Chi training did not affect traditional parameters of standing postural control or respiration, yet reduced the coupling between respiration and postural control. The beneficial effects of Tai Chi training may therefore stem in part

  8. Tai Chi training reduced coupling between respiration and postural control.

    PubMed

    Holmes, Matthew L; Manor, Brad; Hsieh, Wan-hsin; Hu, Kun; Lipsitz, Lewis A; Li, Li

    2016-01-01

    In order to maintain stable upright stance, the postural control system must account for the continuous perturbations to the body's center-of-mass including those caused by spontaneous respiration. Both aging and disease increase "posturo-respiratory synchronization;" which reflects the degree to which respiration affects postural sway fluctuations over time. Tai Chi training emphasizes the coordination of respiration and bodily movements and may therefore optimize the functional interaction between these two systems. The purpose of the project was to examine the effect of Tai Chi training on the interaction between respiration and postural control in older adults. We hypothesized that Tai Chi training would improve the ability of the postural control system to compensate for respiratory perturbations and thus, reduce posturo-respiratory synchronization. Participants were recruited from supportive housing facilities and randomized to a 12-week Tai Chi intervention (n=28; 86 ± 5 yrs) or educational-control program (n=34, 85 ± 6 yrs). Standing postural sway and respiration were simultaneously recorded with a force plate and respiratory belt under eyes-open and eyes-closed conditions. Posturo-respiratory synchronization was determined by quantifying the variation of the phase relationship between the dominant oscillatory mode of respiration and corresponding oscillations within postural sway. Groups were similar in age, gender distribution, height, body mass, and intervention compliance. Neither intervention altered average sway speed, sway magnitude or respiratory rate. As compared to the education-control group, however, Tai Chi training reduced posturo-respiratory synchronization when standing with eyes open or closed (p<0.001). Tai Chi training did not affect traditional parameters of standing postural control or respiration, yet reduced the coupling between respiration and postural control. The beneficial effects of Tai Chi training may therefore stem in part

  9. Evaluating the Evidence for Magnetic Dynamocs in Chondritic Parent Bodies

    NASA Astrophysics Data System (ADS)

    Fu, R. R.; Weiss, B. P.; Krot, A. N.; Kehayias, P.; Glenn, D. R.; Fintor, K.; Pál-Molnár, E.; Bryson, J. F. J.; Walsworth, R. L.

    2016-08-01

    We present paleomagnetic data suggesting that the LL chondrite parent body lacked a magnetic dynamos. We then further test the dynamo hypothesis for the CV parent body by mapping magnetization in Kaba.

  10. Chosen postures during specific sitting activities.

    PubMed

    Kamp, Irene; Kilincsoy, Umit; Vink, Peter

    2011-11-01

    This research study analysed the interaction between people's postures and activities while in semi-public/leisure situations and during transportation (journey by train). In addition, the use of small electronic devices received particular emphasis. Video recordings in German trains and photographs in Dutch semi-public spaces were analysed using a variation of Branton and Grayson's (An evaluation of train seats by observation of sitting behaviour. Ergonomics, 10 (1), (1967), 35-51) postural targeting forms and photos. The analysis suggests a significant relationship between most activities and the position of the head, trunk and arms during transportation situations. The relationship during public situations is less straightforward. Watching, talking/discussing and reading were the most observed activities for the transportation and leisure situations combined. Surprisingly, differences in head, trunk, arm and leg postures were not significant when using small electronic devices. Important issues not considered in this study include the duration of the activities, the gender and age of observed subjects and the influence of the time of day. These are interesting issues to consider and include for future research. STATEMENT OF RELEVANCE: This study shows what activities people choose to carry out and their related postures when not forced to a specific task (e.g. driving). The results of this study can be used for designing comfortable seating in the transportation industry (car passenger, train, bus and aircraft seats) and semi-public/leisure spaces.

  11. Assessing Postural Stability in the Concussed Athlete

    PubMed Central

    Ruhe, Alexander; Fejer, René; Gänsslen, Axel; Klein, Wolfgang

    2014-01-01

    Context: Postural stability assessment is included as part of the diagnostic and monitoring process for sports-related concussions. Particularly, the relatively simple Balance Error Scoring System (BESS) and more sophisticated force plate measures like the Sensory Organization Test (SOT) are suggested. Evidence Acquisition: Relevant studies were identified via the following electronic databases: PubMed, MEDLINE, EMBASE, Web of Science, ScienceDirect, and CINAHL (1980 to July 2013). Inclusion was based on the evaluation of postural sway or balance in concussed athletes of any age or sex and investigating the reliability or validity of the included tests. Study Design: Clinical review. Level of Evidence: Level 4 Results: Both the SOT and the BESS show moderate reliability, but a learning effect due to repetitive testing needs to be considered. Both tests indicate that postural stability returns to baseline by day 3 to 5 in most concussed athletes. While the BESS is a simple and valid method, it is sensitive to subjectivity in scoring and the learning effect. The SOT is very sensitive to even subtle changes in postural sway, and thus, more accurate than the BESS; however, it is a rather expensive method of balance testing. Conclusion: Both tests serve the purpose of monitoring balance performance in the concussed athlete; however, neither may serve as a stand-alone diagnostic or monitoring tool. Strength of Recommendation Taxonomy: B PMID:25177420

  12. Automated contingent reinforcement of correct posture.

    PubMed

    Burch, M R; Clegg, J C; Bailey, J S

    1987-01-01

    This study evaluated the effectiveness of a mercury switch as a self-monitoring device to improve the sitting posture of an adult male. The participant in this study was a 31 year old man who was blind, nonambulatory, and who had been classified in the moderate range of intellectual functioning and in the severe range of adaptive functioning due to physical impairments. After determining that music practice and listening to a game show on the television channel of a radio were powerful reinforcers, a multiple baseline across the two reinforcing activities was implemented. The participant wore a mercury switch inside of a baseball cap which activated a Casio keyboard during music practice and a radio during the independent leisure activity of listening to a game show. During the treatment condition, the keyboard and radio were activated automatically by upright sitting posture. Results indicated that the participant's sitting posture increased from an average of almost 0% correct upright posture during baseline to an average of 52% during treatment.

  13. Evaluation of postural steadiness in below-knee amputees when wearing different prosthetic feet during various sensory conditions using the Biodex® Stability System.

    PubMed

    Arifin, Nooranida; Abu Osman, Noor Azuan; Ali, Sadeeq; Gholizadeh, Hossein; Wan Abas, Wan Abu Bakar

    2015-07-01

    In recent years, computerized posturography has become an essential tool in quantitative assessment of postural steadiness in the clinical settings. The purpose of this study was to explore the ability of the Biodex(®) Stability System (BSS) to quantify postural steadiness in below-knee amputees. A convenience sample of 10 below-knee amputees participated in the study. The overall (OSI), anterior-posterior (APSI) and medial-lateral (MLSI) stability indexes as well as the percentage of time spent in left and right quadrants and four concentric zones were measured under altered sensory conditions while standing with solid ankle cushion heel (SACH), single-axis (SA) and energy storage and release (ESAR) feet. Significant difference was found between sensory conditions in SACH and ESAR feet for OSI (SACH, p = 0.002; ESAR, p = 0.005), APSI (SACH, p = 0.036; ESAR, p = 0.003) and MLSI (SACH, p = 0.008; ESAR, p = 0.05) stability indexes. The percentage of time spent in Zone A (0°-5°) was significantly greater than the other three concentric zones (p < 0.01). The loading time percentage on their intact limb (80%-94%) was significantly longer than the amputated limb (20%-6%) in all conditions for all three prosthetic feet. Below-knee amputees showed compromised postural steadiness when visual, proprioceptive or vestibular sensory input was altered. The findings highlight that the characteristics of postural stability in amputees can be clinically assessed by utilizing the outcomes produced by the BSS.

  14. Vestibular and Somatosensory Covergence in Postural Equilibrium Control: Insights from Spaceflight and Bed Rest Studies

    NASA Technical Reports Server (NTRS)

    Mulavara, A. P.; Batson, C. D.; Buxton, R. E.; Feiveson, A. H.; Kofman, I. S.; Lee, S. M. C.; Miller, C. A.; Peters, B. T.; Phillips, T.; Platts, S. H.; Ploutz-Snyder, L. L.; Reschke, M. F.; Ryder, J. W.; Stenger, M. B.; Taylor, L. C.; Bloomberg, J. J.

    2014-01-01

    The goal of the Functional Task Test study is to determine the effects of space flight on functional tests that are representative of high priority exploration mission tasks and to identify the key underlying physiological factors that contribute to decrements in performance. We are currently conducting studies on both International Space Station (ISS) astronauts experiencing up to 6 months of microgravity and subjects experiencing 70 days of 6??head-down bed-rest as an analog for space flight. Bed-rest provides the opportunity for us to investigate the role of prolonged axial body unloading in isolation from the other physiological effects produced by exposure to the microgravity environment of space flight. This allows us to parse out the contribution of the body unloading somatosensory component on functional performance. Both ISS crewmembers and bed-rest subjects were tested using a protocol that evaluated functional performance along with tests of postural and locomotor control before and after space flight and bed-rest, respectively. Functional tests included ladder climbing, hatch opening, jump down, manual manipulation of objects and tool use, seat egress and obstacle avoidance, recovery from a fall, and object translation tasks. Astronauts were tested three times before flight, and on 1, 6, and 30 days after landing. Bed-rest subjects were tested three times before bed-rest and immediately after getting up from bed-rest as well as 1, 6, and 12 days after re-ambulation. A comparison of bed-rest and space flight data showed a significant concordance in performance changes across all functional tests. Tasks requiring a greater demand for dynamic control of postural equilibrium (i.e. fall recovery, seat egress/obstacle avoidance during walking, object translation, jump down) showed the greatest decrement in performance. Functional tests with reduced requirements for postural stability showed less reduction in performance. Results indicate that body unloading

  15. Postural Stability Characteristics of Transtibial Amputees Wearing Different Prosthetic Foot Types When Standing on Various Support Surfaces

    PubMed Central

    Arifin, Nooranida; Abu Osman, Noor Azuan; Ali, Sadeeq; Wan Abas, Wan Abu Bakar

    2014-01-01

    Purpose. This study aimed to evaluate the effects of prosthetic foot types on the postural stability among transtibial amputees when standing on different support surfaces. Materials and Methods. The postural stability of 10 transtibial amputees wearing solid ankle cushion heel (SACH) foot, single-axis (SA) foot, and energy-saving and return (ESAR) foot was assessed. Results were compared with able-bodied participants. Anterior-posterior stability index (APSI), mediolateral stability index (MLSI), and overall stability index (OSI) were measured by computed posturography in an upright stance on firm, foam, and unstable support surfaces. Results. The mean OSI score of SACH foot was significantly lower than that of an ESAR foot when the participants were standing on a compliant surface. When compared to able-bodied group, MLSI score was significantly higher for each of the prosthetic foot groups while OSI score was significantly higher for ESAR foot only in foam condition. Conclusions. Differences between prosthetic foot types and groups (amputees versus able-bodied) can only be distinguished when individuals were standing on a compliant surface. Amputees exhibited an increased postural instability in the mediolateral direction than able-bodied individuals. Hence, the restoration of stability in the frontal plane and the enhancement of proprioception at the residual limb should be the basis of rehabilitation programs. PMID:25003155

  16. Evaluating indices of body condition in two cricket species

    PubMed Central

    Kelly, Clint D; Tawes, Brittany R; Worthington, Amy M

    2014-01-01

    Body mass components (dry mass, lean dry mass, water mass, fat mass) in each sex correlate strongly with body mass and pronotum length in Gryllus texensis and Acheta domesticus. Ordinary least squares (OLS) regression underestimates the scaling relationship between body mass and structural size (i.e., pronotum length) in both cricket species compared with standard major axis (SMA) regression. Standardized mass components correlate more strongly with scaled mass index () than with residual body mass (R i). R i represents the residuals from an OLS regression of log body mass against log pronotum length. Neither condition index predicts energy stores (i.e., fat content) in G. texensis. R i is not correlated with energy stores in A. domesticus whereas is negatively correlated. A comparison of condition index methods using published data showed that neither sex nor diet quality affected body condition at adulthood in G. texensis when using the scaled mass index. However, the residual index suggested that sex had a significant effect on body condition. Further, analysis of covariance (ANCOVA) suggested that diet quality significantly affects body mass while statistically controlling for body size (i.e., body condition). We conclude that the statistical assumptions of condition index methods must be met prior to use and urge caution when using methods that are based on least squares in the y -plane (i.e., residual index ANCOVA). PMID:25512844

  17. Trained vs untrained evaluator assessment of body condition score as a predictor of percent body fat in adult cats.

    PubMed

    Shoveller, Anna K; DiGennaro, Joe; Lanman, Cynthia; Spangler, Dawn

    2014-12-01

    Body condition scoring (BCS) provides a readily available technique that can be used by both veterinary professionals and owners to assess the body condition of cats, and diagnose overweight or underweight conditions. The objective of this study was to evaluate a five-point BCS system with half-point delineations using dual-energy x-ray absorptiometry (DXA). Four evaluators (a veterinarian, veterinary technician, trained scorer and untrained scorer) assessed 133 neutered adult cats. For all scorers, BCS score was more strongly correlated with percent body fat than with body weight. Percent body fat increased by approximately 7% within each step increase in BCS. The veterinarian had the strongest correlation coefficient between BCS and percent fat (r = 0.80). Mean body fat in cats classified as being in ideal body condition was 12 and 19%, for 3.0 and 3.5 BCS, respectively. Within BCS category, male cats were significantly heavier in body weight than females within the same assigned BCS category. However, DXA-measured percent body fat did not differ significantly between male and female cats within BCS category, as assigned by the veterinarian (P >0.13). Conversely, when assessed by others, mean percent body fat within BCS category was lower in males than females for cats classified as being overweight (BCS >4.0). The results of this study show that using a BCS system that has been validated within a range of normal weight to moderately overweight cats can help to differentiate between lean cats and cats that may not be excessively overweight, but that still carry a higher proportion of body fat.

  18. The Body Appreciation Scale-2: item refinement and psychometric evaluation.

    PubMed

    Tylka, Tracy L; Wood-Barcalow, Nichole L

    2015-01-01

    Considered a positive body image measure, the 13-item Body Appreciation Scale (BAS; Avalos, Tylka, & Wood-Barcalow, 2005) assesses individuals' acceptance of, favorable opinions toward, and respect for their bodies. While the BAS has accrued psychometric support, we improved it by rewording certain BAS items (to eliminate sex-specific versions and body dissatisfaction-based language) and developing additional items based on positive body image research. In three studies, we examined the reworded, newly developed, and retained items to determine their psychometric properties among college and online community (Amazon Mechanical Turk) samples of 820 women and 767 men. After exploratory factor analysis, we retained 10 items (five original BAS items). Confirmatory factor analysis upheld the BAS-2's unidimensionality and invariance across sex and sample type. Its internal consistency, test-retest reliability, and construct (convergent, incremental, and discriminant) validity were supported. The BAS-2 is a psychometrically sound positive body image measure applicable for research and clinical settings.

  19. The Body Appreciation Scale-2: item refinement and psychometric evaluation.

    PubMed

    Tylka, Tracy L; Wood-Barcalow, Nichole L

    2015-01-01

    Considered a positive body image measure, the 13-item Body Appreciation Scale (BAS; Avalos, Tylka, & Wood-Barcalow, 2005) assesses individuals' acceptance of, favorable opinions toward, and respect for their bodies. While the BAS has accrued psychometric support, we improved it by rewording certain BAS items (to eliminate sex-specific versions and body dissatisfaction-based language) and developing additional items based on positive body image research. In three studies, we examined the reworded, newly developed, and retained items to determine their psychometric properties among college and online community (Amazon Mechanical Turk) samples of 820 women and 767 men. After exploratory factor analysis, we retained 10 items (five original BAS items). Confirmatory factor analysis upheld the BAS-2's unidimensionality and invariance across sex and sample type. Its internal consistency, test-retest reliability, and construct (convergent, incremental, and discriminant) validity were supported. The BAS-2 is a psychometrically sound positive body image measure applicable for research and clinical settings. PMID:25462882

  20. Postural Control Deficits in Autism Spectrum Disorder: The Role of Sensory Integration

    ERIC Educational Resources Information Center

    Doumas, Michail; McKenna, Roisin; Murphy, Blain

    2016-01-01

    We investigated the nature of sensory integration deficits in postural control of young adults with ASD. Postural control was assessed in a fixed environment, and in three environments in which sensory information about body sway from visual, proprioceptive or both channels was inaccurate. Furthermore, two levels of inaccurate information were…

  1. Divergent Effects of Cognitive Load on Quiet Stance and Task-Linked Postural Coordination

    ERIC Educational Resources Information Center

    Mitra, Suvobrata; Knight, Alec; Munn, Alexandra

    2013-01-01

    Performing a cognitive task while maintaining upright stance can lead to increased or reduced body sway depending on tasks and experimental conditions. Because greater sway is commonly taken to indicate loosened postural control, and vice versa, the precise impact of cognitive load on postural stability has remained unclear. In much of the large…

  2. Motor Difficulties in Autism Spectrum Disorder: Linking Symptom Severity and Postural Stability

    ERIC Educational Resources Information Center

    Travers, Brittany G.; Powell, Patrick S.; Klinger, Laura G.; Klinger, Mark R.

    2013-01-01

    Postural stability is a fundamental aspect of motor ability that allows individuals to sustain and maintain the desired physical position of one's body. The present study examined postural stability in average-IQ adolescents and adults with Autism Spectrum Disorder (ASD). Twenty-six individuals with ASD and 26 age-and-IQ-matched individuals…

  3. Working postures: a literature review.

    PubMed

    Vieira, Edgar Ramos; Kumar, Shrawan

    2004-06-01

    Working postures are addressed in many papers in the ergonomics field but, surprisingly, scientific literature dealing with working posture itself is not common; knowledge has been elusive. This article reviews the working postures literature. Selected papers published in the English language before March 2003 including the phrase "working postures" in the title, abstract, or keywords were searched in the PubMed, Scirus, and Science Direct databases and reviewed. The literature provides evidence that working postures and musculoskeletal health are related. This relationship is supported by the overexertion, differential fatigue, and cumulative load theories of musculoskeletal injuries' precipitation. Goniometers, inclinometers, photographic techniques, electrogoniometers, and video recording systems are the means that are most often used to measure working postures. Information about working postures need to be collected and analyzed in a more systematic way in order to contribute for a deeper understanding of the relationship between working postures and work-related musculoskeletal disorders. This information will help to improve the control and rehabilitation of these highly prevalent disorders.

  4. Influences of limb proportions and body size on locomotor kinematics in terrestrial primates and fossil hominins.

    PubMed

    Polk, J D

    2004-10-01

    During locomotion, mammalian limb postures are influenced by many factors including the animal's limb length and body mass. Polk (2002) compared the gait of similar-sized cercopithecine monkeys that differed limb proportions and found that longer-limbed monkeys usually adopt more extended joint postures than shorter-limbed monkeys in order to moderate their joint moments. Studies of primates as well as non-primate mammals that vary in body mass have demonstrated that larger animals use more extended limb postures than smaller animals. Such extended postures in larger animals increase the extensor muscle mechanical advantage and allow postures to be maintained with relatively less muscular effort (Polk, 2002; Biewener 1989). The results of these previous studies are used here to address two anthropological questions. The first concerns the postural effects of body mass and limb proportion differences between australopithecines and members of the genus Homo. That is, H. erectus and later hominins all have larger body mass and longer legs than australopithecines, and these anatomical differences suggest that Homo probably used more extended postures and probably required relatively less muscular force to resist gravity than the smaller and shorter-limbed australopithecines. The second question investigates how animals with similar size but different limb proportions differ in locomotor performance. The effects of limb proportions on gait are relevant to inferring postural and locomotor differences between Neanderthals and modern Homo sapiens which differ in their crural indices and relative limb length. This study demonstrates that primates with relatively long limbs achieve higher walking speeds while using lower stride frequencies and lower angular excursions than shorter-limbed monkeys, and these kinematic differences may allow longer-limbed taxa to locomote more efficiently than shorter-limbed species of similar mass. Such differences may also have characterized

  5. Influences of limb proportions and body size on locomotor kinematics in terrestrial primates and fossil hominins.

    PubMed

    Polk, J D

    2004-10-01

    During locomotion, mammalian limb postures are influenced by many factors including the animal's limb length and body mass. Polk (2002) compared the gait of similar-sized cercopithecine monkeys that differed limb proportions and found that longer-limbed monkeys usually adopt more extended joint postures than shorter-limbed monkeys in order to moderate their joint moments. Studies of primates as well as non-primate mammals that vary in body mass have demonstrated that larger animals use more extended limb postures than smaller animals. Such extended postures in larger animals increase the extensor muscle mechanical advantage and allow postures to be maintained with relatively less muscular effort (Polk, 2002; Biewener 1989). The results of these previous studies are used here to address two anthropological questions. The first concerns the postural effects of body mass and limb proportion differences between australopithecines and members of the genus Homo. That is, H. erectus and later hominins all have larger body mass and longer legs than australopithecines, and these anatomical differences suggest that Homo probably used more extended postures and probably required relatively less muscular force to resist gravity than the smaller and shorter-limbed australopithecines. The second question investigates how animals with similar size but different limb proportions differ in locomotor performance. The effects of limb proportions on gait are relevant to inferring postural and locomotor differences between Neanderthals and modern Homo sapiens which differ in their crural indices and relative limb length. This study demonstrates that primates with relatively long limbs achieve higher walking speeds while using lower stride frequencies and lower angular excursions than shorter-limbed monkeys, and these kinematic differences may allow longer-limbed taxa to locomote more efficiently than shorter-limbed species of similar mass. Such differences may also have characterized

  6. Which biomechanical models are currently used in standing posture analysis?

    PubMed

    Crétual, A

    2015-11-01

    In 1995, David Winter concluded that postural analysis of upright stance was often restricted to studying the trajectory of the center of pressure (CoP). However, postural control means regulation of the center of mass (CoM) with respect to CoP. As CoM is only accessible by using a biomechanical model of the human body, the present article proposes to determine which models are actually used in postural analysis, twenty years after Winter's observation. To do so, a selection of 252 representative articles dealing with upright posture and published during the four last years has been checked. It appears that the CoP model largely remains the most common one (accounting for nearly two thirds of the selection). Other models, CoP/CoM and segmental models (with one, two or more segments) are much less used. The choice of the model does not appear to be guided by the population studied. Conversely, while some confusion remains between postural control and the associated concepts of stability or strategy, this choice is better justified for real methodological concerns when dealing with such high-level parameters. Finally, the computation of the CoM continues to be a limitation in achieving a more complete postural analysis. This unfortunately implies that the model is chosen for technological reasons in many cases (choice being a euphemism here). Some effort still has to be made so that bioengineering developments allow us to go beyond this limit. PMID:26388359

  7. Monitoring the prevalence of postural changes in schoolchildren

    PubMed Central

    Nichele da Rosa, Bruna; Noll, Matias; Sedrez, Juliana Adami; Furlanetto, Tassia Silveira; Candotti, Claudia Tarrago

    2016-01-01

    [Purpose] The aim of this study was to identify whether postural changes are prevalent with advancing age using a photogrammetric method performing one-year follow-up study. [Subjects and Methods] Thirty-eight schoolchildren were evaluated in 2011 and 2012 in this cohort study. The subjects underwent a postural evaluation, which involved palpation of reference anatomic points, placement of reflexive markers over the anatomic points, image acquisition, and point digitalization using the Digital Image-based Postural Assessment evaluation software. For data analysis, descriptive statistics and inferential statistics were analyzed by McNemar’s test. [Results] The results showed a significant increase in postural change prevalence for the lumbar spine in the sagittal plane (from 42.2% to 81.6%) and the knees in the frontal plane (from 39.5% to 63.2%) and a significant decrease in the prevalence of scoliosis (from 68.5% to 42.2%). [Conclusion] The findings indicate an increase in the prevalence of postural changes in schoolchildren from Teutônia, RS, Brazil, in 2012 compared with 2011. The development of longitudinal investigations for long-term monitoring of the evolution of posture and of schoolchildren habits’s representing a viable alternative to subsidize health actions. PMID:27065514

  8. Artificial balancer - supporting device for postural reflex.

    PubMed

    Wojtara, Tytus; Sasaki, Makoto; Konosu, Hitoshi; Yamashita, Masashi; Shimoda, Shingo; Alnajjar, Fady; Kimura, Hidenori

    2012-02-01

    The evolutionarily novel ability to keep ones body upright while standing or walking, the human balance, deteriorates in old age or can be compromised after accidents or brain surgeries. With the aged society, age related balance problems are on the rise. Persons with balance problems are more likely to fall during their everyday life routines. Especially in elderly, falls can lead to bone fractures making the patient bedridden, weakening the body and making it more prone to other diseases. Health care expenses for a fall patient are often very high. There is a great deal of research being done on exoskeletons and power assists. However, these technologies concentrate mainly on the amplifications of human muscle power while balance has to be provided by the human themself. Our research has been focused on supporting human balance in harmony with the human's own posture control mechanisms such as postural reflexes. This paper proposes an artificial balancer that supports human balance through acceleration of a flywheel attached to the body. Appropriate correcting torques are generated through our device based on the measurements of body deflections. We have carried out experiments with test persons standing on a platform subject to lateral perturbations and ambulatory experiments while walking on a balance beam. These experiments have demonstrated the effectiveness of our device in supporting balance and the possibility of enhancing balance-keeping capability in human beings through the application of external torque. PMID:22169384

  9. Effect of postural insoles on static and functional balance in children with cerebral palsy: A randomized controlled study

    PubMed Central

    Christovão, Thaluanna C. L.; Pasini, Hugo; Grecco, Luanda A. C.; Ferreira, Luiz A. B.; Duarte, Natália A. C.; Oliveira, Cláudia S.

    2015-01-01

    BACKGROUND: Improved gait efficiency is one of the goals of therapy for children with cerebral palsy (CP). Postural insoles can allow more efficient gait by improving biomechanical alignment. OBJECTIVE: The aim of the present study was to determine the effect of the combination of postural insoles and ankle-foot orthoses on static and functional balance in children with CP. METHOD: A randomized, controlled, double-blind, clinical trial. After meeting legal requirements and the eligibility criteria, 20 children between four and 12 years of age were randomly allocated either to the control group (CG) (n=10) or the experimental group (EG) (n=10). The CG used placebo insoles and the EG used postural insoles. The Berg Balance Scale, Timed Up-and-Go Test, Six-Minute Walk Test, and Gross Motor Function Measure-88 were used to assess balance as well as the determination of oscillations from the center of pressure in the anteroposterior and mediolateral directions with eyes open and closed. Three evaluations were carried out: 1) immediately following placement of the insoles; 2) after three months of insole use; and 3) one month after suspending insole use. RESULTS: The EG achieved significantly better results in comparison to the CG on the Timed Up-and-Go Test as well as body sway in the anteroposterior and mediolateral directions. CONCLUSION: Postural insoles led to an improvement in static balance among children with cerebral palsy, as demonstrated by the reduction in body sway in the anteroposterior and mediolateral directions. Postural insole use also led to a better performance on the Timed Up-and-Go Test. PMID:25651134

  10. Asymmetry of recurrent dynamics as a function of postural stance.

    PubMed

    King, Adam C; Wang, Zheng; Newell, Karl M

    2012-08-01

    This experiment was setup to investigate the deterministic and stochastic properties of the recurrent dynamics of the center of pressure trajectories of each leg (COP(left) and COP(right)) and whole-body (COP(net)) as a function of different foot positions in postural stance (side-by-side, staggered, and tandem standing) and the availability of visual information. The foot position of postural stance can induce degrees of asymmetry of postural instabilities as well as load on each leg that it was hypothesized would influence the deterministic and stochastic properties of COP fluctuations of each leg and of COP(net). Young adults performed two 60 s trials of quiet standing at each posture-vision condition. The availability of visual information increased COP path length, but had no effect on the recurrent dynamics of COP trajectories. Recurrence quantification analysis showed that recurrence, determinism, and entropy were dependent on the direction (AP/ML) of COP motion and foot position during postural stances. The degree of asymmetry between the left and right leg COP dynamics differed across all postural stances and COP(net) dynamics were more similar to those of the more loaded leg. The cross-recurrence quantification analysis also revealed asymmetries in the coordination coupling of AP/ML under each leg; although, these differences were markedly reduced in tandem postures. The findings support the postulation that the asymmetry generated through mechanical constraints (foot position and load) is related to asymmetrical recurrent dynamics of the individual leg and COP(net) based on the degree of postural instability.

  11. Association between temporomandibular disorders and abnormal head postures.

    PubMed

    Faulin, Evandro Francisco; Guedes, Carlos Gramani; Feltrin, Pedro Paulo; Joffiley, Cláudia Maria Mithie Suda Costa

    2015-01-01

    This study examines the possible correlation between the prevalence of temporomandibular disorders (TMD) and different head postures in the frontal and sagittal planes using photographs of undergraduate students in the School of Dentistry at the Universidade de Brasília - UnB, Brazil. In this nonrandomized, cross-sectional study, the diagnoses of TMD were made with the Research Diagnostic Criteria (RDC)/TMD axis I. The craniovertebral angle was used to evaluate forward head posture in the sagittal plane, and the interpupillary line was used to measure head tilt in the frontal plane. The measurements to evaluate head posture were made using the Software for the Assessment of Posture (SAPO). Students were divided into two study groups, based on the presence or absence of TMD. The study group comprised 46 students and the control group comprised 80 students. Data about head posture and TMD were analyzed with the Statistical Package for the Social Sciences, version 13. Most cases of TMD were classified as degenerative processes (group III), followed by disk displacement (group II) and muscle disorders (group I). There was no sex predominance for the type of disorder. No association was found between prevalence rates for head postures in the frontal plane and the occurrence of TMD. The same result was found for the association of TMD diagnosis with craniovertebral angle among men and women, and the group that contained both men and women. Abnormal head postures were common among individuals both with and without TMD. No association was found between head posture evaluated in the frontal and sagittal planes and TMD diagnosis with the use of RDC/TMD.

  12. Postural sway in diabetic peripheral neuropathy among Indian elderly

    PubMed Central

    Dixit, Snehil; Maiya, Arun; Shasthry, B.A.; Kumaran, D. Senthil; Guddattu, Vasudeva

    2015-01-01

    Background & objectives: Diabetic peripheral neuropathy (DPN) is a major complication of type 2 diabetes and have long term complications on the postural control of the affected population. The objectives of this study were to evaluate postural stability in patients with DPN and to examine correlation of Michigan Neuropathy Screening Instrument (MNSI) with duration of diabetes, age and postural stability measures. Methods: Participants were included if they had clinical neuropathy which was defined by MNSI. Sixty one patients gave their consent to participate in the study and were evaluated on posturography for postural stability measures in four conditions. Repeated measures of analysis of variance (RANOVA) was used to analyze the changes in postural stability measures in different conditions. Results: An increase in mean value of postural stability measures was observed for velocity moment 20.4±1.3, 24.3±2.2, 42.3±20.7, 59±43.03, mediolateral displacement 0.21±0.10, 0.22±0.18, 0.03±0.11, 0.34±0.18, and anteroposterior displacement 0.39 ± 0.09, 0.45±0.12, 0.47±0.13, 0.51±0.20 from EO to EC, EOF, and ECF, respectively. There was a significant difference (P<0.05) in participants with DPN, with greater sway amplitude on firm and foam surface in all the conditions. Moderate correlation of MNSI with age (r=0.43) and postural stability measures were also observed. Interpretation & conclusions: Evaluation of postural stability in Indian DPN population suggests balance impairments on either firm and foam surfaces, with greater likelihood of fall being on foam or deformable surfaces among elderly adults with neuropathy (CTRI/2011/07/001884). PMID:26831420

  13. Kinect-based posture tracking for correcting positions during exercise.

    PubMed

    Guerrero, Cesar; Uribe-Quevedo, Alvaro

    2013-01-01

    The Kinect sensor has opened the path for developing numerous applications in several different areas. Medical and health applications are benefiting from the Kinect as it allows non-invasive body motion capture that can be used in motor rehabilitation and phobia treatment. A major advantage of the Kinect is that allows developing solutions that can be used at home or even the office thus, expanding the user freedom for interacting with complementary solutions to its physical activities without requiring any traveling. This paper present a Kinect-based posture tracking software for assisting the user in successfully match postures required in some exercises for strengthen body muscles. Unlike several video games available, this tool offers a user interface for customizing posture parameters, so it can be enhanced by healthcare professionals or by their guidance through the user.

  14. Postural balance and the risk of falling during pregnancy.

    PubMed

    Cakmak, Bulent; Ribeiro, Ana Paula; Inanir, Ahmet

    2016-01-01

    Pregnancy is a physiological process and many changes occur in a woman's body during pregnancy. These changes occur in all systems to varying degrees, including the cardiovascular, respiratory, genitourinary, and musculoskeletal systems. The hormonal, anatomical, and physiological changes occurring during pregnancy result in weight gain, decreased abdominal muscle strength and neuromuscular control, increased ligamentous laxity, and spinal lordosis. These alterations shift the centre of gravity of the body, altering the postural balance and increasing the risk of falls. Falls during pregnancy can cause maternal and foetal complications, such as maternal bone fractures, head injuries, internal haemorrhage, abruption placenta, rupture of the uterus and membranes, and occasionally maternal death or intrauterine foetal demise. Preventative strategies, such as physical exercise and the use of maternity support belts, can increase postural stability and reduce the risk of falls during pregnancy. This article reviews studies that have investigated changes in postural balance and risk of falling during pregnancy. PMID:26212584

  15. Changes in posture through the use of simple inclines with notebook computers placed on a standard desk.

    PubMed

    Asundi, Krishna; Odell, Dan; Luce, Adam; Dennerlein, Jack T

    2012-03-01

    This study evaluated the use of simple inclines as a portable peripheral for improving head and neck postures during notebook computer use on tables in portable environments such as hotel rooms, cafés, and airport lounges. A 3D motion analysis system measured head, neck and right upper extremity postures of 15 participants as they completed a 10 min computer task in six different configurations, all on a fixed height desk: no-incline, 12° incline, 25° incline, no-incline with external mouse, 25° incline with an external mouse, and a commercially available riser with external mouse and keyboard. After completion of the task, subjects rated the configuration for comfort and ease of use and indicated perceived discomfort in several body segments. Compared to the no-incline configuration, use of the 12° incline reduced forward head tilt and neck flexion while increasing wrist extension. The 25° incline further reduced head tilt and neck flexion while further increasing wrist extension. The 25° incline received the lowest comfort and ease of use ratings and the highest perceived discomfort score. For portable, temporary computing environments where internal input devices are used, users may find improved head and neck postures with acceptable wrist extension postures with the utilization of a 12° incline. PMID:21774912

  16. Polyarteritis nodosa: MDCT as a 'One-Stop Shop' Modality for Whole-Body Arterial Evaluation

    SciTech Connect

    Tsai, W.-L.; Tsai, I-C.; Lee Tain; Hsieh, C.-W.

    2008-07-15

    Polyarteritis nodosa is a rare disease, which is characterized by aneurysm formation and occlusion in the arteries of multiple systems. Due to its extensive involvement, whole-body evaluation is necessary for diagnosis and treatment monitoring. We report a case of polyarteritis nodosa using multidetector-row computed tomography (MDCT) as a 'one-stop shop' modality for whole-body arterial evaluation. With precise protocol design, MDCT can be used as a reliable noninvasive modality providing comprehensive whole-body arterial evaluation.

  17. Evaluation of morphological indices and total body electrical conductivity to assess body composition in big brown bats

    USGS Publications Warehouse

    Pearce, R.D.; O'Shea, T.J.; Wunder, B.A.

    2008-01-01

    Bat researchers have used both morphological indices and total body electric conductivity (TOBEC) as proxies for body condition in a variety of studies, but have typically not validated these indices against direct measurement of body composition. We quantified body composition (total carcass lipids) to determine if morphological indices were useful predictors of body condition in big brown bats (Eptesicus fuscus). We also evaluated body composition indirectly by TOBEC using EM-SCAN?? technology. The most important predictors of body composition in multiple regression analysis were body mass-to-forearm ratio (partial r2 = 0.82, P < 0.001) followed by TOBEC measurement (partial r2 = 0.08, P < 0.001) and to a minor extent head length (partial r2 = 0.02, P < 0.05). Morphological condition indices alone may be adequate for some studies because of lower cost and effort. Marking bats with passive integrated transponder (PIT) tags affected TOBEC measurements. ?? Museum and Institute of Zoology PAS.

  18. Postural Instability in Children with ADHD Is Improved by Methylphenidate.

    PubMed

    Bucci, Maria P; Stordeur, Coline; Acquaviva, Eric; Peyre, Hugo; Delorme, Richard

    2016-01-01

    HIGHLIGHTS Both spatial and temporal analyses of the Center of Pressure demonstrate that children with ADHD have poorer postural control than typically developing sex-, age-, and IQ-matched children.Poor sensory integration in postural control could partially explained the deficits in postural stability in children with ADHD.MPH treatment improves postural performance in both spatial and temporal domains in children with ADHD.MPH improves postural control specifically when visual and proprioceptive inputs are misleading.Such improvement could be due to MPH effects on neurons, facilitating cerebellar processing of postural control. The aim of this study was to examine postural control in children with ADHD and explore the effect of methylphenidate (MPH), using spatial and temporal analyses of the center of pressure (CoP). Thirty-eight children with ADHD (mean age 9.82 ± 0.37 years) and 38 sex- age- and IQ-matched children with typically development were examined. Postural stability was evaluated using the Multitest Equilibre machine (Framiral®) at inclusion and after 1 month of MPH in children with ADHD. Postural stability was assessed by recording under several conditions: with eyes open and fixed on a target, with eyes closed and with vision perturbed by optokinetic stimulation, on stable and unstable platforms. At inclusion, we observed poor spatial and temporal postural stability in children with ADHD. The spectral power index was higher in children with ADHD than in controls. Canceling time was shorter at low and medium frequencies of oscillation and longer at higher frequencies in children with ADHD. After 1 month of MPH, the surface area and mean velocity of the CoP decreased significantly under the most complex conditions (unstable platform in the absence of proprioceptive and visual inputs). The spectral power index decreased significantly after MPH while the canceling time did not change. Poor postural control in children with ADHD supports the

  19. Postural Instability in Children with ADHD Is Improved by Methylphenidate

    PubMed Central

    Bucci, Maria P.; Stordeur, Coline; Acquaviva, Eric; Peyre, Hugo; Delorme, Richard

    2016-01-01

    HIGHLIGHTS Both spatial and temporal analyses of the Center of Pressure demonstrate that children with ADHD have poorer postural control than typically developing sex-, age-, and IQ-matched children.Poor sensory integration in postural control could partially explained the deficits in postural stability in children with ADHD.MPH treatment improves postural performance in both spatial and temporal domains in children with ADHD.MPH improves postural control specifically when visual and proprioceptive inputs are misleading.Such improvement could be due to MPH effects on neurons, facilitating cerebellar processing of postural control. The aim of this study was to examine postural control in children with ADHD and explore the effect of methylphenidate (MPH), using spatial and temporal analyses of the center of pressure (CoP). Thirty-eight children with ADHD (mean age 9.82 ± 0.37 years) and 38 sex- age- and IQ-matched children with typically development were examined. Postural stability was evaluated using the Multitest Equilibre machine (Framiral®) at inclusion and after 1 month of MPH in children with ADHD. Postural stability was assessed by recording under several conditions: with eyes open and fixed on a target, with eyes closed and with vision perturbed by optokinetic stimulation, on stable and unstable platforms. At inclusion, we observed poor spatial and temporal postural stability in children with ADHD. The spectral power index was higher in children with ADHD than in controls. Canceling time was shorter at low and medium frequencies of oscillation and longer at higher frequencies in children with ADHD. After 1 month of MPH, the surface area and mean velocity of the CoP decreased significantly under the most complex conditions (unstable platform in the absence of proprioceptive and visual inputs). The spectral power index decreased significantly after MPH while the canceling time did not change. Poor postural control in children with ADHD supports the

  20. Postural Instability in Children with ADHD Is Improved by Methylphenidate.

    PubMed

    Bucci, Maria P; Stordeur, Coline; Acquaviva, Eric; Peyre, Hugo; Delorme, Richard

    2016-01-01

    HIGHLIGHTS Both spatial and temporal analyses of the Center of Pressure demonstrate that children with ADHD have poorer postural control than typically developing sex-, age-, and IQ-matched children.Poor sensory integration in postural control could partially explained the deficits in postural stability in children with ADHD.MPH treatment improves postural performance in both spatial and temporal domains in children with ADHD.MPH improves postural control specifically when visual and proprioceptive inputs are misleading.Such improvement could be due to MPH effects on neurons, facilitating cerebellar processing of postural control. The aim of this study was to examine postural control in children with ADHD and explore the effect of methylphenidate (MPH), using spatial and temporal analyses of the center of pressure (CoP). Thirty-eight children with ADHD (mean age 9.82 ± 0.37 years) and 38 sex- age- and IQ-matched children with typically development were examined. Postural stability was evaluated using the Multitest Equilibre machine (Framiral®) at inclusion and after 1 month of MPH in children with ADHD. Postural stability was assessed by recording under several conditions: with eyes open and fixed on a target, with eyes closed and with vision perturbed by optokinetic stimulation, on stable and unstable platforms. At inclusion, we observed poor spatial and temporal postural stability in children with ADHD. The spectral power index was higher in children with ADHD than in controls. Canceling time was shorter at low and medium frequencies of oscillation and longer at higher frequencies in children with ADHD. After 1 month of MPH, the surface area and mean velocity of the CoP decreased significantly under the most complex conditions (unstable platform in the absence of proprioceptive and visual inputs). The spectral power index decreased significantly after MPH while the canceling time did not change. Poor postural control in children with ADHD supports the

  1. Observing working postures in industry: Examples of OWAS application.

    PubMed

    Karhu, O; Härkönen, R; Sorvali, P; Vepsäläinen, P

    1981-03-01

    A practical method for identifying and evaluating poor working postures, ie the Ovako Working Posture Analysing System (OWAS), was presented in an earlier paper (Karhu et al, 1977). The application of the method is here described by means of two examples. One is a case study undertaken by members of an ergonomics training course, in which a marked improvement in working posture was achieved by OWAS analysis of critical activities. The second illustrates the effect of setting up a multidisciplinary group in order to develop an alternative method for the installation and maintenance of steel mill equipment. In both examples, application of the OWAS method led to improved posture in the situations studied, and to the likelihood of its wider industrial use.

  2. Techniques and Methods for Testing the Postural Function in Healthy and Pathological Subjects

    PubMed Central

    Paillard, Thierry; Noé, Frédéric

    2015-01-01

    The different techniques and methods employed as well as the different quantitative and qualitative variables measured in order to objectify postural control are often chosen without taking into account the population studied, the objective of the postural test, and the environmental conditions. For these reasons, the aim of this review was to present and justify the different testing techniques and methods with their different quantitative and qualitative variables to make it possible to precisely evaluate each sensory, central, and motor component of the postural function according to the experiment protocol under consideration. The main practical and technological methods and techniques used in evaluating postural control were explained and justified according to the experimental protocol defined. The main postural conditions (postural stance, visual condition, balance condition, and test duration) were also analyzed. Moreover, the mechanistic exploration of the postural function often requires implementing disturbing postural conditions by using motor disturbance (mechanical disturbance), sensory stimulation (sensory manipulation), and/or cognitive disturbance (cognitive task associated with maintaining postural balance) protocols. Each type of disturbance was tackled in order to facilitate understanding of subtle postural control mechanisms and the means to explore them. PMID:26640800

  3. Techniques and Methods for Testing the Postural Function in Healthy and Pathological Subjects.

    PubMed

    Paillard, Thierry; Noé, Frédéric

    2015-01-01

    The different techniques and methods employed as well as the different quantitative and qualitative variables measured in order to objectify postural control are often chosen without taking into account the population studied, the objective of the postural test, and the environmental conditions. For these reasons, the aim of this review was to present and justify the different testing techniques and methods with their different quantitative and qualitative variables to make it possible to precisely evaluate each sensory, central, and motor component of the postural function according to the experiment protocol under consideration. The main practical and technological methods and techniques used in evaluating postural control were explained and justified according to the experimental protocol defined. The main postural conditions (postural stance, visual condition, balance condition, and test duration) were also analyzed. Moreover, the mechanistic exploration of the postural function often requires implementing disturbing postural conditions by using motor disturbance (mechanical disturbance), sensory stimulation (sensory manipulation), and/or cognitive disturbance (cognitive task associated with maintaining postural balance) protocols. Each type of disturbance was tackled in order to facilitate understanding of subtle postural control mechanisms and the means to explore them. PMID:26640800

  4. Techniques and Methods for Testing the Postural Function in Healthy and Pathological Subjects.

    PubMed

    Paillard, Thierry; Noé, Frédéric

    2015-01-01

    The different techniques and methods employed as well as the different quantitative and qualitative variables measured in order to objectify postural control are often chosen without taking into account the population studied, the objective of the postural test, and the environmental conditions. For these reasons, the aim of this review was to present and justify the different testing techniques and methods with their different quantitative and qualitative variables to make it possible to precisely evaluate each sensory, central, and motor component of the postural function according to the experiment protocol under consideration. The main practical and technological methods and techniques used in evaluating postural control were explained and justified according to the experimental protocol defined. The main postural conditions (postural stance, visual condition, balance condition, and test duration) were also analyzed. Moreover, the mechanistic exploration of the postural function often requires implementing disturbing postural conditions by using motor disturbance (mechanical disturbance), sensory stimulation (sensory manipulation), and/or cognitive disturbance (cognitive task associated with maintaining postural balance) protocols. Each type of disturbance was tackled in order to facilitate understanding of subtle postural control mechanisms and the means to explore them.

  5. A statistical model including age to predict passenger postures in the rear seats of automobiles.

    PubMed

    Park, Jangwoon; Ebert, Sheila M; Reed, Matthew P; Hallman, Jason J

    2016-06-01

    Few statistical models of rear seat passenger posture have been published, and none has taken into account the effects of occupant age. This study developed new statistical models for predicting passenger postures in the rear seats of automobiles. Postures of 89 adults with a wide range of age and body size were measured in a laboratory mock-up in seven seat configurations. Posture-prediction models for female and male passengers were separately developed by stepwise regression using age, body dimensions, seat configurations and two-way interactions as potential predictors. Passenger posture was significantly associated with age and the effects of other two-way interaction variables depended on age. A set of posture-prediction models are presented for women and men, and the prediction results are compared with previously published models. This study is the first study of passenger posture to include a large cohort of older passengers and the first to report a significant effect of age for adults. The presented models can be used to position computational and physical human models for vehicle design and assessment. Practitioner Summary: The significant effects of age, body dimensions and seat configuration on rear seat passenger posture were identified. The models can be used to accurately position computational human models or crash test dummies for older passengers in known rear seat configurations.

  6. A statistical model including age to predict passenger postures in the rear seats of automobiles.

    PubMed

    Park, Jangwoon; Ebert, Sheila M; Reed, Matthew P; Hallman, Jason J

    2016-06-01

    Few statistical models of rear seat passenger posture have been published, and none has taken into account the effects of occupant age. This study developed new statistical models for predicting passenger postures in the rear seats of automobiles. Postures of 89 adults with a wide range of age and body size were measured in a laboratory mock-up in seven seat configurations. Posture-prediction models for female and male passengers were separately developed by stepwise regression using age, body dimensions, seat configurations and two-way interactions as potential predictors. Passenger posture was significantly associated with age and the effects of other two-way interaction variables depended on age. A set of posture-prediction models are presented for women and men, and the prediction results are compared with previously published models. This study is the first study of passenger posture to include a large cohort of older passengers and the first to report a significant effect of age for adults. The presented models can be used to position computational and physical human models for vehicle design and assessment. Practitioner Summary: The significant effects of age, body dimensions and seat configuration on rear seat passenger posture were identified. The models can be used to accurately position computational human models or crash test dummies for older passengers in known rear seat configurations. PMID:26328769

  7. Effect of posture on arterial oxygenation in patients with chronic obstructive pulmonary disease.

    PubMed

    Ries, A L; Kaplan, R M; Chang, J

    1992-01-01

    We studied 117 patients with chronic obstructive pulmonary disease (COPD) to evaluate (1) the frequency and magnitude of postural changes in resting arterial oxygenation and (2) the relationship of these changes to other measures of pulmonary function and exercise arterial blood gases. Compared to the supine measurement, room air PaO2 measured while standing increased more than 3 mm Hg in 28 patients (group 1), did not change (+/- 3 mm Hg) in 57 patients (group 2), and decreased more than 3 mm Hg in 32 patients (group 3) (range = 31 mm Hg increase to 20 mm Hg decrease). Patients in group 1 had significantly less severe disease than patients in the other two groups. There were no significant pulmonary function differences between groups 2 and 3. Supine PaO2 was similar for all groups, suggesting that standing PaO2 accounted for the postural change in PaO2. Because of unpredictable postural changes in PaO2 in patients with COPD, we believe that body position should be noted for arterial blood gas measurements and should be kept constant for valid comparison of serial measurements. These findings may also be important for other diffuse lung diseases.

  8. Do Equilibrium Constraints Modulate Postural Reaction when Viewing Imbalance?

    ERIC Educational Resources Information Center

    Tia, Banty; Paizis, Christos; Mourey, France; Pozzo, Thierry

    2012-01-01

    Action observation and action execution are tightly coupled on a neurophysiological and a behavioral level, such that visually perceiving an action can contaminate simultaneous and subsequent action execution. More specifically, observing a model in postural disequilibrium was shown to induce an increase in observers' body sway. Here we…

  9. Downsizing a giant: re-evaluating Dreadnoughtus body mass

    PubMed Central

    Bates, Karl T.; Falkingham, Peter L.; Macaulay, Sophie; Brassey, Charlotte; Maidment, Susannah C. R.

    2015-01-01

    Estimates of body mass often represent the founding assumption on which biomechanical and macroevolutionary hypotheses are based. Recently, a scaling equation was applied to a newly discovered titanosaurian sauropod dinosaur (Dreadnoughtus), yielding a 59 300 kg body mass estimate for this animal. Herein, we use a modelling approach to examine the plausibility of this mass estimate for Dreadnoughtus. We find that 59 300 kg for Dreadnoughtus is highly implausible and demonstrate that masses above 40 000 kg require high body densities and expansions of soft tissue volume outside the skeleton several times greater than found in living quadrupedal mammals. Similar results from a small sample of other archosaurs suggests that lower-end mass estimates derived from scaling equations are most plausible for Dreadnoughtus, based on existing volumetric and density data from extant animals. Although volumetric models appear to more tightly constrain dinosaur body mass, there remains a clear need to further support these models with more exhaustive data from living animals. The relative and absolute discrepancies in mass predictions between volumetric models and scaling equations also indicate a need to systematically compare predictions across a wide size and taxonomic range to better inform studies of dinosaur body size. PMID:26063751

  10. Pharmacokinetics of pyridostigmine in a child with postural tachycardia syndrome.

    PubMed

    Filler, Guido; Gow, Robert M; Nadarajah, Renisha; Jacob, Pierre; Johnson, Gillian; Zhang, Yan-Ling; Christians, Uwe

    2006-11-01

    Pyridostigmine has been proposed for the treatment of postural orthostatic tachycardia syndrome in adults at a dose of 60 mg twice daily, but no dosing recommendation exists for children. With the approval of our local ethics board, we tested the pharmacokinetics of pyridostigmine in 6 children with myasthenia and a pediatric index patient with severe postural orthostatic tachycardia syndrome whose condition failed all conventional therapy and who had developed significant postural hypertension. Pyridostigmine was quantified by using a validated, semiautomated, and specific high-performance liquid chromatography/tandem mass spectrometry assay in combination with online column-switching extraction and turbo electrospray ionization. The patient with postural orthostatic tachycardia syndrome showed a dose-dependent favorable response to oral pyridostigmine. Pharmacokinetic evaluation revealed a short half-life of 2.29 hours, similar to the 2.0 +/- 0.63 hours in the patients with myasthenia. The patient with postural orthostatic tachycardia syndrome has subsequently been treated at a dose of 45 mg in the morning, 30 mg at lunchtime, and 15 mg at bedtime; after 9 months, there has been persistent positive effect and without additional blood pressure medication. No major adverse effects occurred. Pyridostigmine has been a safe and effective treatment modality for this child with postural orthostatic tachycardia syndrome. The short half-life suggests that dosing 3 times per day is preferable.

  11. Postural syncope: mechanisms and management.

    PubMed

    Vaddadi, Gautam; Lambert, Elisabeth; Corcoran, Susan J; Esler, Murray D

    2007-09-01

    Postural syncope is a transient loss of consciousness secondary to a reduction in cerebral blood flow and is typically precipitated by standing. It is the commonest cause of recurrent transient loss of consciousness. Recurrent unexplained postural syncope is most often due to one of the five disorders of circulatory control: vasovagal syncope, postural tachycardia syndrome, chronic autonomic failure, initial orthostatic hypotension, or persistently low supine systolic blood pressure. Failure to identify the underlying cause of postural syncope can result in ongoing morbidity, impaired quality of life and high health care costs. With a detailed history, examination, blood pressure assessment and electrocardiography, most disorders of circulatory control can be diagnosed. In difficult cases, analysis of sympathetic nervous system and circulatory responses during head-up tilting can aid diagnosis. Treatment is challenging and compounded by a lack of evidence. Most patients can be managed in an outpatient setting, and hospital admission or emergency department assessment is rarely warranted.

  12. Postural control deficits in people with fibromyalgia: a pilot study

    PubMed Central

    2011-01-01

    Introduction Postural instability and falls are increasingly recognized problems in patients with fibromyalgia (FM). The purpose of this study was to determine whether FM patients, compared to age-matched healthy controls (HCs), have differences in dynamic posturography, including sensory, motor, and limits of stability. We further sought to determine whether postural instability is associated with strength, proprioception and lower-extremity myofascial trigger points (MTPs); FM symptoms and physical function; dyscognition; balance confidence; and medication use. Last, we evaluated self-reported of falls over the past six months. Methods In this cross-sectional study, we compared middle-aged FM patients and age-matched HCs who underwent computerized dynamic posturography testing and completed the Fibromyalgia Impact Questionnaire-Revised (FIQR) and balance and fall questionnaires. All subjects underwent a neurological and musculoskeletal examination. Descriptive statistics were used to characterize the sample and explore the relationships between variables. The relationships between subjective, clinical and objective variables were evaluated by correlation and regression analyses. Results Twenty-five FM patients and twenty-seven HCs (combined mean age ± standard deviation (SD): 48.6 ± 9.7 years) completed testing. FM patients scored statistically lower on composite sensory organization tests (primary outcome; P < 0.010), as well as with regard to vestibular, visual and somatosensory ratio scores on dynamic posturography. Balance confidence was significantly different between groups, with FM patients reporting less confidence than HCs (mean ± SD: 81.24 ± 19.52 vs. 98.52 ± 2.45; P < 0.001). Interestingly, 76% to 84% of FM patients had gastrocnemius and/or anterior tibialis MTPs. Postural stability was best predicted by dyscognition, FIQR score and body mass index. Regarding falls, 3 (11%) of 27 HCs had fallen only once during the past 6 months, whereas 18 (72

  13. Design for manufacturability evaluation: Composite NIF Pockel Cell body

    SciTech Connect

    Jensen, W.A.; Spellman, G.P.

    1994-04-01

    A survey of composite materials and processes for the NIF Optical Switch Body is described. Mechanical and physical criterion set upon the part are used as guidelines for the selection of materials and processes for manufacturing. Benefits, costs, and risks associated with selected processes, as well as a recommendation for prototype fabrication is presented.

  14. Postural reorganization induced by torso cutaneous covibration.

    PubMed

    Lee, Beom-Chan; Martin, Bernard J; Ho, Allison; Sienko, Kathleen H

    2013-05-01

    Cutaneous information from joints has been attributed proprioceptive properties similar to those of muscle spindles. This study aimed to assess whether vibration-induced changes in torso cutaneous information contribute to whole-body postural reorganization in humans. Ten healthy young adults stood in normal and Romberg stances with six vibrating actuators positioned on the torso in contact with the skin over the left and right external oblique, internal oblique, and erector spinae muscle locations at the L4/L5 vertebrae level. Vibrations around the torso were randomly applied at two locations simultaneously (covibration) or at all locations simultaneously. Kinematic analysis of the body segments indicated that covibration applied to the skin over the internal oblique muscles induced shifts of both the head and torso in the anterior direction (torso flexion) while the hips shifted in the posterior direction (ankle plantar flexion). Conversely, covibration applied to the skin over the erector spinae muscle locations produced opposite effects. However, covibration applied to the skin over the left internal oblique and left erector spinae, the right internal oblique and right erector spinae, or at all locations simultaneously did not induce any significant postural changes. In addition, the center of pressure position as measured by the force plate was unaffected by all covibration conditions tested. These results were independent of stance and suggest an integrated and coordinated reorganization of posture in response to vibration-induced changes in cutaneous information. In addition, combinations of vibrotactile stimuli over multiple locations exhibit directional summation properties in contrast to the individual responses we observed in our previous work. PMID:23637178

  15. Evolution of Sports-medical Team Management in the Program of Posture Correction in Children

    PubMed Central

    Torlakovic, Aldvin; Muftic, Mirsad; Radjo, Izet; Talovic, Munir; Mahmutovic, Ifet

    2014-01-01

    Goals: The goal of this study was to determine the effectiveness of the organization and coordination of multidisciplinary team consisted of health and kinesiology professionals at the correction of posture among girls in the period of the second phase of intense growth and development. Material and methods: Testing was conducted on a sample of 70 girls, aged 11.9±2.3 years, in which by the expert evaluation is recorded weakness of individual muscle groups, but also of the whole musculature. For the assessment of posture we applied the method of Napoleon Wolanski. Used are 9 variables that included the observed region of the body and an overall assessment of posture. The subjects were included in the program of kinesiology treatment with duration of 28 weeks. For all the parameters have been applied statistical procedures at univariate and multivariate level. Results: Data on subjects were obtained by measuring the same variables at two time points, i.e. before and after the application of kinesiology treatments. Analyses of differences arithmetic mean and mean values were done with the t-test for paired samples. In order to determine global quantitative differences of tested variables tested discriminant analysis was applied. The results showed that the models which complement the experience and practical application of expert health professionals and kinesiology knowledge is a very effective tool for improving posture of girls in the second phase of intensive growth and development. In this way can be prevented health problems that might arise later in life. PMID:24944533

  16. Computer technology to evaluate body composition, nutrition, and exercise.

    PubMed

    Katch, F I; Katch, V L

    1983-09-01

    The use of computer technology has made it possible to make accurate determinations of body composition, nutrition, and exercise. With the FITCOMP computer assessment system, detailed measurements of physique status have been made on a variety of world-class athletes, including professional football and baseball players, as well as on diverse groups of young and older men and women throughout the United States. The FITCOMP measurement system allows the user a choice of measurement techniques: fatfolds, girths, bone diameters, and hydrostatic weighing. Combined with body composition assessment is a nutrition and exercise plan. The nutrition plan is based on guidelines formulated by the American Dietetic Association. This application of computer technology is unique, because individuals can select the foods they will eat from a list of preferred choices from the basic food groups. Individual menu plans for breakfast, lunch, and dinner are generated to provide an optimal blend of nutrients aimed at achieving ideal body mass and fat percentage. This is coupled with an aerobic exercise program that is selected by the individual from nine different forms, including walking, jogging, running, swimming, cycling, and various sport activities. The caloric output is designed to reduce total body fat through reductions in body weight of 1.4 to 2.5 pounds per week, depending on the exercise selected and total weight loss necessary to achieve a weight goal (and ideal fat percentage). The aerobic exercise plan is based on the method of overload, where intensity and duration are periodically increased dependent on individual capabilities. The use of fitness-oriented computer technology makes it possible to prepare detailed reports about current status and progress as well as to systematize record keeping.

  17. Use of a Cutaneous Body Image (CBI) scale to evaluate self perception of body image in acne vulgaris.

    PubMed

    Amr, Mostafa; Kaliyadan, Feroze; Shams, Tarek

    2014-01-01

    Skin disorders such as acne, which have significant cosmetic implications, can affect the self-perception of cutaneous body image. There are many scales which measure self-perception of cutaneous body image. We evaluated the use of a simple Cutaneous Body Image (CBI) scale to assess self-perception of body image in a sample of young Arab patients affected with acne. A total of 70 patients with acne answered the CBI questionnaire. The CBI score was correlated with the severity of acne and acne scarring, gender, and history of retinoids use. There was no statistically significant correlation between CBI and the other parameters - gender, acne/acne scarring severity, and use of retinoids. Our study suggests that cutaneous body image perception in Arab patients with acne was not dependent on variables like gender and severity of acne or acne scarring. A simple CBI scale alone is not a sufficiently reliable tool to assess self-perception of body image in patients with acne vulgaris.

  18. Evaluation of lumbar vertebra injury risk to the seated human body when exposed to vertical vibration

    NASA Astrophysics Data System (ADS)

    Ayari, H.; Thomas, M.; Doré, S.; Serrus, O.

    2009-03-01

    The objective of this research is to numerically determine the levels of vibration not to exceed accordingly to the corresponding dynamic stresses in the lumbar rachis when exposed to whole-body vibrations in order to identify the risk of adverse health effect to which professional heavy equipment drivers are particularly prone. A parametric finite element model of the lumbar rachis is generated in order to compute the modal parameters, the dynamic stresses and forces under harmonic excitations in a seated posture. The stress analysis reveals that the areas exposed to the highest fracture risk are the cancellous bone of the vertebral body as well as the vertebral endplate when vertical vibrations are transmitted from a seat to the lumbar spine of a driver. An injury risk factor has been developed in order to estimate the risk of adverse health effect arising from mechanical vibrations. It is shown that the injury risk factor increases with the age and consequently that the excitation amplitude must be limited to lower levels when age increases.

  19. Effects of disease severity and medication state on postural control asymmetry during challenging postural tasks in individuals with Parkinson's disease.

    PubMed

    Barbieri, Fabio A; Polastri, Paula F; Baptista, André M; Lirani-Silva, Ellen; Simieli, Lucas; Orcioli-Silva, Diego; Beretta, Victor S; Gobbi, Lilian T B

    2016-04-01

    The aim of this study was to investigate the effects of disease severity and medication state on postural control asymmetry during challenging tasks in individuals with Parkinson's disease (PD). Nineteen people with PD and 11 neurologically healthy individuals performed three standing task conditions: bipedal standing, tandem and unipedal adapted standing; the individuals with PD performed the tasks in ON and OFF medication state. The participants with PD were distributed into 2 groups according to disease severity: unilateral group (n=8) and bilateral group (n=11). The two PD groups performed the evaluations both under and without the medication. Two force plates were used to analyze the posture. The symmetric index was calculated for various of center of pressure. ANOVA one-way (groups) and two-way (PD groups×medication), with repeated measures for medication, were calculated. For main effects of group, the bilateral group was more asymmetric than CG. For main effects of medication, only unipedal adapted standing presented effects of PD medication. There was PD groups×medication interaction. Under the effects of medication, the unilateral group presented lower asymmetry of RMS in anterior-posterior direction and area than the bilateral group in unipedal adapted standing. In addition, the unilateral group presented lower asymmetry of mean velocity, RMS in anterior-posterior direction and area in unipedal standing and area in tandem adapted standing after a medication dose. Postural control asymmetry during challenging postural tasks was dependent on disease severity and medication state in people with PD. The bilateral group presented higher postural control asymmetry than the control and unilateral groups in challenging postural tasks. Finally, the medication dose was able to reduce postural control asymmetry in the unilateral group during challenging postural tasks.

  20. Analysis of working postures at a construction site using the OWAS method.

    PubMed

    Lee, Tzu-Hsien; Han, Chia-Shan

    2013-01-01

    This study used OWAS to analyze the working postures of construction workers on building the foundations of a log cabin. Three construction workers, with an average work experience of 40 years, participated in this study. Eight elementary jobs of building the foundations of a log cabin were videotaped at a construction site and analyzed later in the laboratory. For an overall distribution of trunk postures, OWAS identified that a bent and twisted trunk posture (34%), which fell into action category 3, was the major poor posture for construction workers. This study also identified that tying beams with steel bars, assembling column templates, and cement grouting of the ground were the 3 principal jobs in which workers building the foundations exhibited poor working posture. This article suggests ways to reduce and evaluate poor posture in a dynamic construction site.

  1. Analysis of postural load during tasks related to milking cows-a case study.

    PubMed

    Groborz, Anna; Tokarski, Tomasz; Roman-Liu, Danuta

    2011-01-01

    The aim of this study was to analyse postural load during tasks related to milking cows of 2 farmers on 2 different farms (one with a manual milk transport system, the other with a fully automated milk transport system) as a case study. The participants were full-time farmers, they were both healthy and experienced in their job. The Ovako Working Posture Analyzing System (OWAS) was used to evaluate postural load and postural risk. Postural load was medium for the farmer on the farm with a manual milk transport system and high for the farmer working on the farm with a fully automated milk transport system. Thus, it can be concluded that a higher level of farm mechanization not always mean that the farmer's postural load is lower, but limitation of OWAS should be considered.

  2. Analysis of postural load during tasks related to milking cows-a case study.

    PubMed

    Groborz, Anna; Tokarski, Tomasz; Roman-Liu, Danuta

    2011-01-01

    The aim of this study was to analyse postural load during tasks related to milking cows of 2 farmers on 2 different farms (one with a manual milk transport system, the other with a fully automated milk transport system) as a case study. The participants were full-time farmers, they were both healthy and experienced in their job. The Ovako Working Posture Analyzing System (OWAS) was used to evaluate postural load and postural risk. Postural load was medium for the farmer on the farm with a manual milk transport system and high for the farmer working on the farm with a fully automated milk transport system. Thus, it can be concluded that a higher level of farm mechanization not always mean that the farmer's postural load is lower, but limitation of OWAS should be considered. PMID:22152507

  3. Postconcussion Postural Sway Variability Changes in Youth: The Benefit of Structural Variability Analyses

    PubMed Central

    Quatman-Yates, Catherine C.; Bonnette, Scott; Hugentobler, Jason A.; Médé, Butovens; Kiefer, Adam W.; Kurowski, Brad G.; Riley, Michael A.

    2016-01-01

    Purpose The purpose of this study was to evaluate the utility of postural sway variability as a potential assessment to detect altered postural sway in youth with symptoms related to a concussion. Methods Forty participants (20 who were healthy and 20 who were injured) aged 10 to 16 years were assessed using the Balance Error Scoring System (BESS) and postural sway variability analyses applied to center-of-pressure data captured using a force plate. Results Significant differences were observed between the 2 groups for postural sway variability metrics but not for the BESS. Specifically, path length was shorter and Sample and Renyi Entropies were more regular for the participants who were injured compared with the participants who were healthy (P < .05). Conclusion The results of this study indicate that postural sway variability may be a more valid measure than the BESS to detect postconcussion alterations in postural control in young athletes. PMID:26397071

  4. The effects of horse-riding simulator exercise and Kendall exercise on the forward head posture.

    PubMed

    Kim, Ki-Hyun; Kim, Seong-Gil; Hwangbo, Gak

    2015-04-01

    [Purpose] The aim of this study was to examine the effects of horse-riding simulator exercise and Kendall exercise on forward head posture. [Subjects and Methods] Thirty elderly college students with a forward head posture were randomly divided into two groups for 15 persons each, a horse-riding simulator group and Kendall exercise group, and performed exercise for eight weeks. [Results] The horse-riding simulator group and Kendall exercise group showed significant differences after the intervention in New York state posture rating, craniovertebral angle, and cranial rotation angle. The horse-riding simulator group showed a significantly smaller value than the Kendall exercise group for New York state posture rating evaluation after the intervention. [Conclusion] The results of this study indicate that horse-riding simulator exercise is more effective on forward head posture than Kendall exercise. Therefore, horse-riding simulator exercise can be used as a new simple treatment method for the ever-growing forward head posture.

  5. Time for a change to assess and evaluate body temperature in clinical practice.

    PubMed

    Sund-Levander, Märtha; Grodzinsky, Ewa

    2009-08-01

    The definition of normal body temperature as 37 degrees C still is considered the norm worldwide, but in practice there is a widespread confusion of the evaluation of body temperature, especially in elderly individuals. In this paper, we discuss the relevance of normal body temperature as 37 degrees C and consequences in clinical practice. Our conclusion is that body temperature should be evaluated in relation to the individual variability and that the best approach is to use the same site, and an unadjusted mode without adjustments to other sites. If the baseline value is not known, it is important to notice that frail elderly individuals are at risk of a low body temperature. In addition, what should be regarded as fever is closely related to what is considered as normal body temperature. That is, as normal body temperature shows individual variations, it is reasonable that the same should hold true for the febrile range. PMID:19703039

  6. Comprehensive Evaluation for Obesity: Beyond Body Mass Index.

    PubMed

    Cetin, Derrick; Lessig, Bailey A; Nasr, Elie

    2016-06-01

    Many factors contribute to the diagnosis of obesity in a patient. Anthropometric measurements, such as the waist circumference and percentage of body fat, are used in the newly released obesity algorithm to risk stratify patients. Staging methods, which use the identification of comorbidities and disease burden to assess the severity of obesity, can result in treating a patient sooner than if the traditional body mass index is used. Obesity is a growing concern in the medical field, and providing additional avenues through which to diagnose obesity and address obesity-related health risks can improve prevention efforts and lead to expedited weight management. Obesity is a growing concern in the medical field, and providing additional avenues through which to diagnose obesity and address obesity-related health risks can improve prevention efforts and lead to expedited weight management. PMID:27214774

  7. Whole-body MRI evaluation of facioscapulohumeral muscular dystrophy

    PubMed Central

    Leung, Doris G.; Carrino, John A.; Wagner, Kathryn R.; Jacobs, Michael A.

    2015-01-01

    Introduction Facioscapulohumeral muscular dystrophy (FSHD) is a hereditary disorder that causes progressive muscle wasting. Increasing knowledge of the pathophysiology of FSHD has stimulated interest in developing biomarkers of disease severity. Methods Two groups of MRI scans were analyzed: whole-body scans from 13 subjects with FSHD, and upper and lower extremity scans from 34 subjects with FSHD who participated in the MYO-029 clinical trial. Muscles were scored for fat infiltration and edema-like changes. Fat infiltration scores were compared to muscle strength and function. Results Our analysis reveals a distinctive pattern of both frequent muscle involvement and frequent sparing in FSHD. Averaged fat infiltration scores for muscle groups in the legs correlated with quantitative muscle strength and 10-meter walk times. Discussion Advances in MRI technology allow for the acquisition of rapid, high-quality whole-body imaging in diffuse muscle disease. This technique offers a promising disease biomarker in FSHD and other muscle diseases. PMID:25641525

  8. Evaluating Descent and Ascent Trajectories Near Non-Spherical Bodies

    NASA Technical Reports Server (NTRS)

    Werner, Robert A.

    2010-01-01

    Spacecraft landing on small bodies pass through regions where conventional gravitation formulations using exterior spherical harmonics are inaccurate. An investigation shows that a formulation using interior solid spherical harmonics might be satisfactory. Interior spherical harmonic expansions are usable inside an imaginary, empty sphere. For this application, such a sphere could be positioned in empty space above the intended landing site and rotating with the body. When the spacecraft is inside this sphere, the interior harmonic expansion would be used instead of the conventional, exterior harmonic expansion. Coefficients can be determined by a least-squares fit to gravitation measurements synthesized from conventional formulations. Due to their unfamiliarity, recurrences for interior, as well as exterior, expansions are derived. Hotine's technique for partial derivatives of exterior spherical harmonics is extended to interior harmonics.

  9. Slowed muscle force production and sensory organization deficits contribute to altered postural control strategies in children with developmental coordination disorder.

    PubMed

    Fong, Shirley S M; Ng, Shamay S M; Yiu, Beverley P H L

    2013-09-01

    This study aimed to (1) compare the postural control strategies, sensory organization of balance control, and lower limb muscle performance of children with and without developmental coordination disorder (DCD) and (2) determine the association between postural control strategies, sensory organization parameters and knee muscle performance indices among children with DCD. Fifty-eight DCD-affected children and 46 typically developing children participated in the study. Postural control strategies and sensory organization were evaluated with the sensory organization test (SOT). Knee muscle strength and time to produce maximum muscle torque (at 180°/s) were assessed using an isokinetic machine. Analysis of variance was used to compare the outcome variables between groups, and multiple regression analysis was used to examine the relationships between postural control strategies, sensory organization parameters, and isokinetic indices in children with DCD. The DCD group had significantly lower strategy scores (SOT conditions 5 and 6), lower visual and vestibular ratios, and took a longer time to reach peak torque in the knee flexor muscles than the control group (p>0.05). After accounting for age, sex, and body mass index, the vestibular ratio explained 35.8% of the variance in the strategy score of SOT condition 5 (p<0.05). Moreover, the visual ratio, vestibular ratio, and time to peak torque of the knee flexors were all significant predictors (p<0.05) of the strategy score during SOT condition 6, accounting for 14, 19.7, and 19.8% of its variance, respectively. The children with DCD demonstrated deficits in postural control strategy, sensory organization and prolonged duration of muscle force development. Slowed knee muscle force production combined with poor visual and vestibular functioning may result in greater use of hip strategy by children with DCD in sensory challenging environments.

  10. Real-Time Hand Posture Recognition Using a Range Camera

    NASA Astrophysics Data System (ADS)

    Lahamy, Herve

    The basic goal of human computer interaction is to improve the interaction between users and computers by making computers more usable and receptive to the user's needs. Within this context, the use of hand postures in replacement of traditional devices such as keyboards, mice and joysticks is being explored by many researchers. The goal is to interpret human postures via mathematical algorithms. Hand posture recognition has gained popularity in recent years, and could become the future tool for humans to interact with computers or virtual environments. An exhaustive description of the frequently used methods available in literature for hand posture recognition is provided. It focuses on the different types of sensors and data used, the segmentation and tracking methods, the features used to represent the hand postures as well as the classifiers considered in the recognition process. Those methods are usually presented as highly robust with a recognition rate close to 100%. However, a couple of critical points necessary for a successful real-time hand posture recognition system require major improvement. Those points include the features used to represent the hand segment, the number of postures simultaneously recognizable, the invariance of the features with respect to rotation, translation and scale and also the behavior of the classifiers against non-perfect hand segments for example segments including part of the arm or missing part of the palm. A 3D time-of-flight camera named SR4000 has been chosen to develop a new methodology because of its capability to provide in real-time and at high frame rate 3D information on the scene imaged. This sensor has been described and evaluated for its capability for capturing in real-time a moving hand. A new recognition method that uses the 3D information provided by the range camera to recognize hand postures has been proposed. The different steps of this methodology including the segmentation, the tracking, the hand

  11. Postural deficits in Huntington's disease when performing motor skills involved in daily living.

    PubMed

    Panzera, Robert; Salomonczyk, Danielle; Pirogovosky, Eva; Simmons, Roger; Goldstein, Jody; Corey-Bloom, Jody; Gilbert, Paul E

    2011-03-01

    Previous studies of Huntington's disease (HD) have reported motor control deficits for selected fine and gross motor skills. However, no studies have metrically assessed postural control in this clinical group when performing motor skills involved in daily living. Therefore, the purpose of the present study was to evaluate and compare postural control of individuals with confirmed Huntington's disease and non-gene carriers when completing three functional postural tasks. Eleven individuals with HD (mean age=47.1 years: UHDRS mean=34.5: mean age of HD onset 34.6 years: mean CAG repeat=44.1) and 17 non-gene carriers (NGC) (mean age=39.2 years: UHDRS mean=0.13: mean CAG repeat=20.5) completed three tests on a force plate interfaced with a computer. The tests were a step up and over an obstacle (SUO) test, a sit-to-stand (STS) test, and a step and turn (ST) test. Selected kinematic and kinetic variables were used to quantify postural control. Data were analyzed using MANOVA procedures and discriminant function analysis. HD patients were significantly slower in completing all three tests (HD SUO=2.3 s vs. NGC SUO=1.6 s; HD STS=0.8 s vs. NGC STS=0.5 s; HD ST=1.7 s vs. NGC ST=0.9 s) and developed less rising force during the step up and over test (HD=25.8% body weight vs. NGC=39.4% body weight) but not for the sit-to-stand test. Additionally, sway velocity of the center of gravity (COG) was significantly higher for HD patients when performing the sit-to-stand (HD=4.1°/s vs. NGC=2.9°/s) and step and turn tests (HD=33.7°/s vs. NGC=21.7°/s). HD patients manifest significant postural control deficits when performing motor skills typical of daily living activities. PMID:21256027

  12. Effect of Cognitive Load on Seating Posture in Children.

    PubMed

    Igarashi, Go; Karashima, Chieko; Hoshiyama, Minoru

    2016-03-01

    Although children are frequently required to sit upright, it is often difficult to maintain this posture when performing cognitive tasks. Information about the relationship between a cognitive tasks and postural seating control is important for children to complete tasks more effectively. To determine the muscle activity and body sway of children in a seated posture while performing a cognitive task, changes in muscle activity and center of pressure (COP) were recorded while 4(th) grade children performed arithmetic tasks. Electromyography was recorded from the internal oblique and lumbar multifidus muscles, and the COP was recorded using a baropodometer placed on the stool. These variables were measured during easy (EA) and difficult (DA) arithmetic tasks. EMG activity decreased during the EA and DA tasks, while the COP was displaced in the DA task. The results of the arithmetic tasks were not related to the EMG or COP changes. Attention to maintain a seated posture may be reduced when children perform cognitive tasks. Therefore, it may be better to allow children to alter their posture especially when they are performing difficult tasks. In this research, we only used arithmetic tasks as the cognitive exercise, and therefore, other types of tasks should be examined. PMID:26317316

  13. Postural control in children with typical development and children with profound hearing loss

    PubMed Central

    de Sousa, Aneliza Maria Monteiro; de França Barros, Jônatas; de Sousa Neto, Brígido Martins

    2012-01-01

    Purpose To describe the behavior of the postural control in children with profound sensorineural hearing loss and compare the results of experimental tests with hearing children aged 7 to 10 years. Patients and methods This is a cross-sectional study where 100 children were divided into experimental and control groups. We used a force platform, AccuSway Plus, where the tests were conducted under the experimental conditions: open base, eyes open (OBEO); open base, eyes closed (OBEC); closed base, eyes open (CBEO); closed base, eyes closed (CBEC). The body sway velocity (V) of the center of pressure, the displacement in the anteroposterior direction (COPap) and mediolateral (COPml) of the center of pressure were the parameters to evaluate the postural control. For statistical analysis we used the nonparametric Mann–Whitney U test, with a significance level of 5%. Results In comparisons of variables between the groups, the experimental group outperformed by at least 75% of the control group values. In terms of global trends, the experimental group shows higher values of body oscillations in all experimental conditions and variables evaluated. Children with hearing loss had poorer balance performance compared to the group of hearing. The inferential analysis revealed a statistically significant difference in the balance between deaf and hearing children in the OBEC experimental condition in relation to the COPml parameter (P = 0.04). There were no statistically significant differences in comparisons between the sexes when the groups were analyzed separately. The prevalence of unknown etiology showed 58% of cases and congenital rubella in 16%. The discovery of deafness occurred in 70% of children before the age of 3 years. Conclusion In this study, children with hearing loss had poorer balance performance compared to the group of hearing children. This finding confirms the need to investigate postural control through longitudinal studies to identify the area of

  14. The influence of peripheral vision induced by moving people on postural control in healthy adults

    PubMed Central

    Kim, Soo-Han; Park, Du-Jin

    2016-01-01

    This study was conducted to examine the influence of the peripheral vision (PV) induced by moving people on postural control in healthy adults. The subjects consisted of 12 healthy adult volunteers (5 males, 7 females) who had been informed of the study purpose and procedure. The visual interventions were composed of three types. PV1 and PV2 were stimulated using a one-way vertical striped pattern and a two-way vertical striped pattern, respectively. To embody the features of moving people reflected in the mirrors, researchers recorded movements of people or objects provided by mirrors on video image. In this study, this was named PV3. The subjects were exposed to each of the visual stimuli for 3 min in a random order, and their postural control was then evaluated. All the subjects were allowed to practice once prior to performing the one leg stand test, functional reaching test and body sway test. All the evaluations were made before and after the visual intervention, and the subjects rested for 30 min between each intervention. PV3 ranked second in before and after differences of trace length and velocity and had no significant difference from PV2, demonstrating that the PV3, as well as PV2, affected the amount and velocity of body sway. In addition, the standard deviation velocity, trace length and velocity values of PV3 were higher than the PV1 values. Therefore, the treatment of those who have difficulty with postural control and balance maintenance should take place in a controlled therapeutic environment. PMID:27807518

  15. Effects of galvanic vestibular stimulation on postural limb reflexes and neurons of spinal postural network.

    PubMed

    Hsu, L-J; Zelenin, P V; Orlovsky, G N; Deliagina, T G

    2012-07-01

    Quadrupeds maintain the dorsal side up body orientation due to the activity of the postural control system driven by limb mechanoreceptors. Binaural galvanic vestibular stimulation (GVS) causes a lateral body sway toward the anode. Previously, we have shown that this new position is actively stabilized, suggesting that GVS changes a set point in the reflex mechanisms controlling body posture. The aim of the present study was to reveal the underlying neuronal mechanisms. Experiments were performed on decerebrate rabbits. The vertebral column was rigidly fixed, whereas hindlimbs were positioned on a platform. Periodic lateral tilts of the platform caused postural limb reflexes (PLRs): activation of extensors in the loaded and flexing limb and a decrease in extensor activity in the opposite (unloaded and extending) limb. Putative spinal interneurons were recorded in segments L4-L5 during PLRs, with and without GVS. We have found that GVS enhanced PLRs on the cathode side and reduced them on the anode side. This asymmetry in PLRs can account for changes in the stabilized body orientation observed in normal rabbits subjected to continuous GVS. Responses to platform tilts (frequency modulation) were observed in 106 spinal neurons, suggesting that they can contribute to PLR generation. Two neuron groups were active in opposite phases of the tilt cycle of the ipsi-limb: F-neurons in the flexion phase, and E-neurons in the extension phase. Neurons were driven mainly by afferent input from the ipsi-limb. If one supposes that F- and E-neurons contribute, respectively, to excitation and inhibition of extensor motoneurons, one can expect that the pattern of response to GVS in F-neurons will be similar to that in extensor muscles, whereas E-neurons will have an opposite pattern. We have found that ~40% of all modulated neurons meet this condition, suggesting that they contribute to the generation of PLRs and to the GVS-caused changes in PLRs.

  16. Sensorimotor integration in human postural control

    NASA Technical Reports Server (NTRS)

    Peterka, R. J.

    2002-01-01

    It is generally accepted that human bipedal upright stance is achieved by feedback mechanisms that generate an appropriate corrective torque based on body-sway motion detected primarily by visual, vestibular, and proprioceptive sensory systems. Because orientation information from the various senses is not always available (eyes closed) or accurate (compliant support surface), the postural control system must somehow adjust to maintain stance in a wide variety of environmental conditions. This is the sensorimotor integration problem that we investigated by evoking anterior-posterior (AP) body sway using pseudorandom rotation of the visual surround and/or support surface (amplitudes 0.5-8 degrees ) in both normal subjects and subjects with severe bilateral vestibular loss (VL). AP rotation of body center-of-mass (COM) was measured in response to six conditions offering different combinations of available sensory information. Stimulus-response data were analyzed using spectral analysis to compute transfer functions and coherence functions over a frequency range from 0.017 to 2.23 Hz. Stimulus-response data were quite linear for any given condition and amplitude. However, overall behavior in normal subjects was nonlinear because gain decreased and phase functions sometimes changed with increasing stimulus amplitude. "Sensory channel reweighting" could account for this nonlinear behavior with subjects showing increasing reliance on vestibular cues as stimulus amplitudes increased. VL subjects could not perform this reweighting, and their stimulus-response behavior remained quite linear. Transfer function curve fits based on a simple feedback control model provided estimates of postural stiffness, damping, and feedback time delay. There were only small changes in these parameters with increasing visual stimulus amplitude. However, stiffness increased as much as 60% with increasing support surface amplitude. To maintain postural stability and avoid resonant behavior, an

  17. Evaluating small-body landing hazards due to blocks

    NASA Astrophysics Data System (ADS)

    Ernst, C.; Rodgers, D.; Barnouin, O.; Murchie, S.; Chabot, N.

    2014-07-01

    Introduction: Landed missions represent a vital stage of spacecraft exploration of planetary bodies. Landed science allows for a wide variety of measurements essential to unraveling the origin and evolution of a body that are not possible remotely, including but not limited to compositional measurements, microscopic grain characterization, and the physical properties of the regolith. To date, two spacecraft have performed soft landings on the surface of a small body. In 2001, the Near Earth Asteroid Rendezvous (NEAR) mission performed a controlled descent and landing on (433) Eros following the completion of its mission [1]; in 2005, the Hayabusa spacecraft performed two touch-and-go maneuvers at (25143) Itokawa [2]. Both landings were preceded by rendezvous spacecraft reconnaissance, which enabled selection of a safe landing site. Three current missions have plans to land on small bodies (Rosetta, Hayabusa 2, and OSIRIS-REx); several other mission concepts also include small-body landings. Small-body landers need to land at sites having slopes and block abundances within spacecraft design limits. Due to the small scale of the potential hazards, it can be difficult or impossible to fully characterize a landing surface before the arrival of the spacecraft at the body. Although a rendezvous mission phase can provide global reconnaissance from which a landing site can be chosen, reasonable a priori assurance that a safe landing site exists is needed to validate the design approach for the spacecraft. Method: Many robotic spacecraft have landed safely on the Moon and Mars. Images of these landing sites, as well as more recent, extremely high-resolution orbital datasets, have enabled the comparison of orbital block observations to the smaller blocks that pose hazards to landers. Analyses of the Surveyor [3], Viking 1 and 2, Mars Pathfinder, Phoenix, Spirit, Opportunity, and Curiosity landing sites [4--8] have indicated that for a reasonable difference in size (a factor

  18. Postural Responses Following Space Flight and Ground Based Analogs

    NASA Technical Reports Server (NTRS)

    Kofman, Igor S.; Reschke, Millard F.; Cerisano, Jody M.; Fisher, Elizabeth A.; Tomilovskaya, Elena V.; Kozlovskaya, Inessa B.; Bloomberg, Jacob B.

    2013-01-01

    With the transition from the Shuttle program to the International Space Station (ISS), the opportunity to fly sensorimotor experiments in a weightless environment has become increasingly more difficult to obtain. As a result, more investigations have turned to ground-based analogs as a way of evaluating an experiment's viability. The two primary analogs available to most investigators are 6deg head down bed rest (HDBR) and dry immersion (DI). For the time being, HDBR investigations have been associated with studies conducted in the United States while the Russians and several other European Union states have concentrated their efforts on using DI as the space flight analog of choice. While either model may be viable for cardiovascular, bone and other system changes, vestibular and sensorimotor investigators have retained serious reservations of either analog's potential to serve as a replacement for a true weightless environment. These reservations have merit, but it is worthwhile to consider that not all changes associated with sensorimotor function during space flight are the result of top-down modifications, but may also be due to the lack, or change, of appropriate support surfaces applying force to the bottom of the feet. To this end we have compared quiet stance postural responses between short duration Space Shuttle flights, long duration ISS flights and HDBR of varying duration. Using these three platforms, representing different modifications of support we investigated postural ataxia using a quiet stance model. Quiet stance was obtained by asking the subjects to stand upright on a force plate, eyes open, arms at the side of the body for three min. From the force plate we obtained average sway velocity in two axes as well as length of line (stabilogram). These parameters were then related to EMG activity recorded from the medial gastrocnemius and lateral tibialis. It is significant to note that postural ataxia measured as quiet stance shows analogous

  19. The stimuli evoking the aerial-righting posture of falling pea aphids.

    PubMed

    Meresman, Yonatan; Ribak, Gal; Weihs, Daniel; Inbar, Moshe

    2014-10-01

    Some wingless insects possess aerial righting reflexes, suggesting that adaptation for controlling body orientation while falling through air could have preceded flight. When threatened by natural enemies, wingless pea aphids (Acyrthosiphon pisum) may drop off their host plant and assume a stereotypic posture that rotates them in midair to land on their feet. The sensory information triggering aphids to assume this posture has so far been unknown. We subjected aphids to a series of tests, isolating the sensory cues experienced during free-fall. Falling aphids assumed the righting posture and landed upright irrespective of whether the experiments were carried out in the light or in complete darkness. Detachment of the tarsi from the substrate triggered the aphids to assume the posture rapidly, but only for a brief period. Rotation (mainly roll and yaw) of the body in air, in the light, caused aphids to assume the posture and remain in it throughout rotation. In contrast, aphids rotated in the dark did not respond. Acceleration associated with falling or airflow over the body per se did not trigger the posture. However, sensing motion relative to air heightened the aphids' responsiveness to rotation in the light. These results suggest that the righting posture of aphids is triggered by a tarsal reflex, but, once the aphid is airborne, vision and a sense of motion relative to air can augment the response. Hence, aerial righting in a wingless insect could have emerged as a basic tarsal response and developed further to include secondary sensory cues typical of falling.

  20. Bioceramic fabrics improve quiet standing posture and handstand stability in expert gymnasts.

    PubMed

    Cian, C; Gianocca, V; Barraud, P A; Guerraz, M; Bresciani, J P

    2015-10-01

    Bioceramic fabrics have been claimed to improve blood circulation, thermoregulation and muscle relaxation, thereby also improving muscular activity. Here we tested whether bioceramic fabrics have an effect on postural control and contribute to improve postural stability. In Experiment 1, we tested whether bioceramic fabrics contribute to reduce body-sway when maintaining standard standing posture. In Experiment 2, we measured the effect of bioceramic fabrics on body-sway when maintaining a more instable posture, namely a handstand hold. For both experiments, postural oscillations were measured using a force platform with four strain gauges that recorded the displacements of the center of pressure (CoP) in the horizontal plane. In half of the trials, the participants wore a full-body second skin suit containing a bioceramic layer. In the other half of the trials, they wore a 'placebo' second skin suit that had the same cut, appearance and elasticity as the bioceramic suit but did not contain the bioceramic layer. In both experiments, the surface of displacement of the CoP was significantly smaller when participants were wearing the bioceramic suit than when they were wearing the placebo suit. The results suggest that bioceramic fabrics do have an effect on postural control and improve postural stability. PMID:26234473

  1. Is Radiologic Evaluation Necessary to Find out Foreign Bodies in Nasal Cavity?

    PubMed

    Oh, Hoon; Min, Hyun Jin; Yang, Hoon Shik; Kim, Kyung Soo

    2016-01-01

    Although there were previous studies on the clinical aspects such as etiology, treatment modalities, studies regarding the necessity of radiologic evaluation for nasal foreign body were limited. The aim of this study is to evaluate the necessity and indication of radiologic evaluation for nasal foreign bodies. There are consecutive patients aged less than 10 years who presented with suspected foreign bodies in nasal cavity. We reviewed the patient's age and sex, including the methods of evaluation, management tools, and types of foreign bodies. There were 35 cases (11.4%) on whom radiographs were performed in the 24 uncooperative patients and 11 cooperative patients who were not identified with any foreign bodies via nasal endoscopy. Among them, only 4 cases had positive reports of foreign body and the others were normal radiologic findings. We suggest that the radiologic evaluation is always not necessary to find the location of nasal foreign bodies. It, however, should be performed in cases of negative findings of physical examination with anterior rhinoscopy or sinus endoscopy and unwitnessed foreign bodies to rule out metallic contents, especially button type battery. PMID:26703025

  2. Is Radiologic Evaluation Necessary to Find out Foreign Bodies in Nasal Cavity?

    PubMed

    Oh, Hoon; Min, Hyun Jin; Yang, Hoon Shik; Kim, Kyung Soo

    2016-01-01

    Although there were previous studies on the clinical aspects such as etiology, treatment modalities, studies regarding the necessity of radiologic evaluation for nasal foreign body were limited. The aim of this study is to evaluate the necessity and indication of radiologic evaluation for nasal foreign bodies. There are consecutive patients aged less than 10 years who presented with suspected foreign bodies in nasal cavity. We reviewed the patient's age and sex, including the methods of evaluation, management tools, and types of foreign bodies. There were 35 cases (11.4%) on whom radiographs were performed in the 24 uncooperative patients and 11 cooperative patients who were not identified with any foreign bodies via nasal endoscopy. Among them, only 4 cases had positive reports of foreign body and the others were normal radiologic findings. We suggest that the radiologic evaluation is always not necessary to find the location of nasal foreign bodies. It, however, should be performed in cases of negative findings of physical examination with anterior rhinoscopy or sinus endoscopy and unwitnessed foreign bodies to rule out metallic contents, especially button type battery.

  3. Effects of elastic band exercise on subjects with rounded shoulder posture and forward head posture

    PubMed Central

    Kim, Tae-Woon; An, Da-In; Lee, Hye-Yun; Jeong, Ho-Young; Kim, Dong-Hyun; Sung, Yun-Hee

    2016-01-01

    [Purpose] This study performed to investigate the effect of elastic band exercise program on the posture of subjects with rounded shoulder and forward head posture. [Subjects and Methods] The body length, forward shoulder angle, craniovertebral angle, and cranial rotation angle of participants (n=12) were measured before and after the exercise program. Furthermore, the thicknesses of the pectoralis major, rhomboid major, and upper trapezius were measured using an ultrasonographic imaging device. The exercises program was conducted with elastic bands, with 15 repetitions per set and 3 sets in total. [Results] The length of the pectoralis major, forward shoulder angle, and craniovertebral angle showed significant changes between before and after the exercise program, whereas the changes in the other measurements were not significant. The thickness of the upper trapezius showed a significant increase between before and after the elastic band exercise. [Conclusion] These findings suggest that the elastic band exercise program used in the study is effective for lengthening the pectoralis major and correcting rounded shoulder and forward head posture. PMID:27390405

  4. (De)stabilization of Required and Spontaneous Postural Dynamics with Learning

    ERIC Educational Resources Information Center

    Faugloire, Elise; Bardy, Benoit G.; Stoffregen, Thomas A.

    2009-01-01

    The present research examined how learning a new ankle-hip coordination influenced the preexisting postural repertoire. Standing participants learned a new ankle-hip coordination mode (relative phase of 90[degrees]). Before and after practice, postural patterns were evaluated in two different tasks. In the required task, specific ankle-hip…

  5. An ergonomic study on posture-related discomfort among preadolescent agricultural workers of West Bengal, India.

    PubMed

    Gangopadhyay, Somnath; Das, Banibrata; Das, Tamal; Ghoshal, Goutam

    2005-01-01

    In India, particularly in West Bengal, preadolescents are primarily associated with agricultural work in rural areas. Owing to poor socio-economic conditions, they are compelled to carry out a considerable number of manual, rigorous tasks in agricultural fields. The main aim of this study was to investigate postures adopted by preadolescent agricultural workers during individual agricultural activities and to analyze the causes of discomfort related to those postures. Fifty male and 50 female preadolescent agricultural workers were randomly selected and a detailed posture analysis was performed with the Ovako Working Posture Analysis System (OWAS). It was observed that those workers worked continuously in awkward postures during certain agricultural activities. Consequently they suffered from discomfort in different parts of their body. Even though they were very young, they were likely to suffer from serious musculoskeletal disorders in the future.

  6. Putative spinal interneurons mediating postural limb reflexes provide basis for postural control in different planes

    PubMed Central

    Zelenin, Pavel V.; Hsu, Li-Ju; Lyalka, Vladimir F.; Orlovsky, Grigori N.; Deliagina, Tatiana G.

    2014-01-01

    The dorsal-side-up trunk orientation in standing quadrupeds is maintained by the postural system driven mainly by somatosensory inputs from the limbs. Postural limb reflexes (PLRs) represent a substantial component of this system. Earlier we described spinal neurons presumably contributing to the generation of PLRs. The first aim of the present study was to reveal trends in the distribution of neurons with different parameters of PLR-related activity across the gray matter of the spinal cord. The second aim was to estimate the contribution of PLR-related neurons with different patterns of convergence of sensory inputs from the limbs to stabilization of body orientation in different planes. For this purpose, the head and vertebral column of the decerebrate rabbit were fixed, whereas the hindlimbs were positioned on a platform. Activity of individual neurons from L5–L6 was recorded during PLRs evoked by lateral tilts of the platform. In addition, the neurons were tested by tilts of the platform under only the ipsilateral or only the contralateral limb, as well as during in-phase tilts of the platforms under both limbs. We found that, across the spinal gray matter, strength of PLR-related neuronal activity and sensory input from the ipsi-limb decreased in the dorso-ventral direction, while strength of the input from the contra-limb increased. A near linear summation of tilt-related sensory inputs from different limbs was found. Functional roles were proposed for individual neurons. The obtained data present the first characterization of posture-related spinal neurons, forming a basis for studies of postural networks impaired by injury. PMID:25370349

  7. The Role of Anticipatory Postural Adjustments in Compensatory Control of Posture: 2. Biomechanical Analysis

    PubMed Central

    Santos, Marcio J.; Kanekar, Neeta; Aruin, Alexander S.

    2010-01-01

    The central nervous system (CNS) utilizes anticipatory (APAs) and compensatory (CPAs) postural adjustments to maintain equilibrium while standing. It is known that these postural adjustments involve displacements of the center of mass (COM) and center of pressure (COP). The purpose of the study was to investigate the relationship between APAs and CPAs from a kinetic and kinematic perspective. Eight subjects were exposed to external predictable and unpredictable perturbations induced at the shoulder level while standing. Kinematic and kinetic data were recorded and analyzed during the time duration typical for anticipatory and compensatory postural adjustments. When the perturbations were unpredictable, the COM and COP displacements were larger compared to predictable conditions with APAs. Thus, the peak of COM displacement, after the pendulum impact, in the posterior direction reached 28 ± 9.6 mm in the unpredictable conditions with no APAs whereas it was 1.6 times smaller, reaching 17 ± 5.5 mm during predictable perturbations. Similarly, after the impact, the peak of COP displacement in the posterior direction was 60 ± 14 mm for unpredictable conditions and 28 ± 3.6 mm for predictable conditions. Finally, the times of the peak COM and COP displacements were similar in the predictable and unpredictable conditions. This outcome provides additional knowledge about how body balance is controlled in presence and in absence of information about the forthcoming perturbation. Moreover, it suggests that control of posture could be enhanced by better utilization of APAs and such an approach could be considered as a valuable modality in the rehabilitation of individuals with balance impairment. PMID:20156693

  8. Meta-Analysis: Association Between Wrist Posture and Carpal Tunnel Syndrome Among Workers

    PubMed Central

    You, Doohee; Smith, Allan H.; Rempel, David

    2014-01-01

    Background Carpal tunnel syndrome (CTS) is a common work-related peripheral neuropathy. In addition to grip force and repetitive hand exertions, wrist posture (hyperextension and hyperflexion) may be a risk factor for CTS among workers. However, findings of studies evaluating the relationship between wrist posture and CTS are inconsistent. The purpose of this paper was to conduct a meta-analysis of existing studies to evaluate the evidence of the relationship between wrist posture at work and risk of CTS. Methods PubMed and Google Scholar were searched to identify relevant studies published between 1980 and 2012. The following search terms were used: “work related”, “carpal tunnel syndrome”, “wrist posture”, and “epidemiology”. The studies defined wrist posture as the deviation of the wrist in extension or flexion from a neutral wrist posture. Relative risk (RR) of individual studies for postural risk was pooled to evaluate the overall risk of wrist posture on CTS. Results Nine studies met the inclusion criteria. All were cross-sectional or case–control designs and relied on self-report or observer's estimates for wrist posture assessment. The pooled RR of work-related CTS increased with increasing hours of exposure to wrist deviation or extension/flexion [RR = 2.01; 95% confidence interval (CI): 1.646–2.43; p < 0.01: Shore-adjusted 95% CI: 1.32–2.97]. Conclusion We found evidence that prolonged exposure to non-neutral wrist postures is associated with a twofold increased risk for CTS compared with low hours of exposure to non-neutral wrist postures. Workplace interventions to prevent CTS should incorporate training and engineering interventions that reduce sustained non-neutral wrist postures. PMID:24932417

  9. An investigation of rugby scrimmaging posture and individual maximum pushing force.

    PubMed

    Wu, Wen-Lan; Chang, Jyh-Jong; Wu, Jia-Hroung; Guo, Lan-Yuen

    2007-02-01

    Although rugby is a popular contact sport and the isokinetic muscle torque assessment has recently found widespread application in the field of sports medicine, little research has examined the factors associated with the performance of game-specific skills directly by using the isokinetic-type rugby scrimmaging machine. This study is designed to (a) measure and observe the differences in the maximum individual pushing forward force produced by scrimmaging in different body postures (3 body heights x 2 foot positions) with a self-developed rugby scrimmaging machine and (b) observe the variations in hip, knee, and ankle angles at different body postures and explore the relationship between these angle values and the individual maximum pushing force. Ten national rugby players were invited to participate in the examination. The experimental equipment included a self-developed rugby scrimmaging machine and a 3-dimensional motion analysis system. Our results showed that the foot positions (parallel and nonparallel foot positions) do not affect the maximum pushing force; however, the maximum pushing force was significantly lower in posture I (36% body height) than in posture II (38%) and posture III (40%). The maximum forward force in posture III (40% body height) was also slightly greater than for the scrum in posture II (38% body height). In addition, it was determined that hip, knee, and ankle angles under parallel feet positioning are factors that are closely negatively related in terms of affecting maximum pushing force in scrimmaging. In cross-feet postures, there was a positive correlation between individual forward force and hip angle of the rear leg. From our results, we can conclude that if the player stands in an appropriate starting position at the early stage of scrimmaging, it will benefit the forward force production. PMID:17313278

  10. Evaluation of body composition during low-dose estrogen oral contraceptives treatment.

    PubMed

    Franchini, M; Caruso, C; Nigrelli, S; Poggiali, C

    1995-01-01

    The effect of two low-dose oral contraceptives (OCs) on weight and body composition was evaluated in 80 family planning clinic outpatients 18-43 years of age. These women were randomly assigned to receive OCs containing either 20 mcg ethinyl estradiol and 150 mcg desogestrel or 30 mcg ethinyl estradiol and 75 mcg gestodene. 20 IUD users served as controls. Anthropometric measurements and body composition (estimated by Bioelectrical Impedance Analysis) were assessed at baseline and after 6 and 12 months of OC use. In all three groups, body weight, body mass index, total body water, and body cellular mass remained unchanged during the 12-month study period. These findings confirm that the new low-dose OCs have no significant effects on body weight or composition.

  11. Temporal parameter change of human postural control ability during upright swing using recursive least square method

    NASA Astrophysics Data System (ADS)

    Goto, Akifumi; Ishida, Mizuri; Sagawa, Koichi

    2010-01-01

    The purpose of this study is to derive quantitative assessment indicators of the human postural control ability. An inverted pendulum is applied to standing human body and is controlled by ankle joint torque according to PD control method in sagittal plane. Torque control parameters (KP: proportional gain, KD: derivative gain) and pole placements of postural control system are estimated with time from inclination angle variation using fixed trace method as recursive least square method. Eight young healthy volunteers are participated in the experiment, in which volunteers are asked to incline forward as far as and as fast as possible 10 times over 10 [s] stationary intervals with their neck joint, hip joint and knee joint fixed, and then return to initial upright posture. The inclination angle is measured by an optical motion capture system. Three conditions are introduced to simulate unstable standing posture; 1) eyes-opened posture for healthy condition, 2) eyes-closed posture for visual impaired and 3) one-legged posture for lower-extremity muscle weakness. The estimated parameters Kp, KD and pole placements are applied to multiple comparison test among all stability conditions. The test results indicate that Kp, KD and real pole reflect effect of lower-extremity muscle weakness and KD also represents effect of visual impairment. It is suggested that the proposed method is valid for quantitative assessment of standing postural control ability.

  12. Temporal parameter change of human postural control ability during upright swing using recursive least square method

    NASA Astrophysics Data System (ADS)

    Goto, Akifumi; Ishida, Mizuri; Sagawa, Koichi

    2009-12-01

    The purpose of this study is to derive quantitative assessment indicators of the human postural control ability. An inverted pendulum is applied to standing human body and is controlled by ankle joint torque according to PD control method in sagittal plane. Torque control parameters (KP: proportional gain, KD: derivative gain) and pole placements of postural control system are estimated with time from inclination angle variation using fixed trace method as recursive least square method. Eight young healthy volunteers are participated in the experiment, in which volunteers are asked to incline forward as far as and as fast as possible 10 times over 10 [s] stationary intervals with their neck joint, hip joint and knee joint fixed, and then return to initial upright posture. The inclination angle is measured by an optical motion capture system. Three conditions are introduced to simulate unstable standing posture; 1) eyes-opened posture for healthy condition, 2) eyes-closed posture for visual impaired and 3) one-legged posture for lower-extremity muscle weakness. The estimated parameters Kp, KD and pole placements are applied to multiple comparison test among all stability conditions. The test results indicate that Kp, KD and real pole reflect effect of lower-extremity muscle weakness and KD also represents effect of visual impairment. It is suggested that the proposed method is valid for quantitative assessment of standing postural control ability.

  13. Body water compartments during bed rest: Evaluation of analytical methods

    NASA Technical Reports Server (NTRS)

    Young, H. L.; Juhos, L.; Castle, B. L.; Yusken, J.; Greenleaf, J. E.

    1973-01-01

    Nine healthy young men were studied to determine the reproducibility and interchangeability of the use of radio-iodinated human serum albumin and Evans Blue dye for estimating plasma volume, sodium bromide for extracellular fluid volume, and deuterium oxide for total body water volume. All subjects were tested in a semibasal condition and allowed to rest for at least 30 min. after arriving at the laboratory. The results indicate that there was uniform distribution of I131 and Evans Blue dye 10 min. after injection and of NaBr and D2O 3 hours after oral ingestion; the buildup of residual tracer did not interfere appreciably with the measurement of either or Evans Blue spaces when they are administered at equal intervals, and the buildup of background tracer after ingestion of NaBr and D2O once per week for three consecutive weeks did not affect the accuracy of the measurement. It was found that I131 and Evans Blue may be used interchangeably for estimating plasma volume; for estimating bromide and D2O spaces, one 3-hour equilibrium blood sample gives results similar to the extrapolation of multiple samples.

  14. Assisting People with Multiple Disabilities Actively Correct Abnormal Standing Posture with a Nintendo Wii Balance Board through Controlling Environmental Stimulation

    ERIC Educational Resources Information Center

    Shih, Ching-Hsiang; Shih, Ching-Tien; Chu, Chiung-Ling

    2010-01-01

    The latest researches adopted software technology turning the Nintendo Wii Balance Board into a high performance change of standing posture (CSP) detector, and assessed whether two persons with multiple disabilities would be able to control environmental stimulation using body swing (changing standing posture). This study extends Wii Balance Board…

  15. A Comparison of the Effects of Feedback and Prompts on Safe Sitting Posture: Utilizing an Automated Observation and Feedback System

    ERIC Educational Resources Information Center

    Moon, Kwangsu; Oah, Shezeen

    2013-01-01

    This study used an ABCB within-subjects design to examine the relative effects of feedback and prompts on safe sitting posture. Participants were three office workers. The dependent variables were the percentages of time the participants spent in four safe individual body positions and in the safe overall sitting posture. After baseline (A),…

  16. Postural Tachycardia Syndrome: Beyond Orthostatic Intolerance.

    PubMed

    Garland, Emily M; Celedonio, Jorge E; Raj, Satish R

    2015-09-01

    Postural tachycardia syndrome (POTS) is a form of chronic orthostatic intolerance for which the hallmark physiological trait is an excessive increase in heart rate with assumption of upright posture. The orthostatic tachycardia occurs in the absence of orthostatic hypotension and is associated with a >6-month history of symptoms that are relieved by recumbence. The heart rate abnormality and orthostatic symptoms should not be caused by medications that impair autonomic regulation or by debilitating disorders that can cause tachycardia. POTS is a "final common pathway" for a number of overlapping pathophysiologies, including an autonomic neuropathy in the lower body, hypovolemia, elevated sympathetic tone, mast cell activation, deconditioning, and autoantibodies. Not only may patients be affected by more than one of these pathophysiologies but also the phenotype of POTS has similarities to a number of other disorders, e.g., chronic fatigue syndrome, Ehlers-Danlos syndrome, vasovagal syncope, and inappropriate sinus tachycardia. POTS can be treated with a combination of non-pharmacological approaches, a structured exercise training program, and often some pharmacological support.

  17. Postural Tachycardia Syndrome: Beyond Orthostatic Intolerance

    PubMed Central

    Garland, Emily M; Celedonio, Jorge E; Raj, Satish R

    2015-01-01

    Postural Tachycardia Syndrome (POTS) is a form of chronic orthostatic intolerance for which the hallmark physiological trait is an excessive increase in heart rate with assumption of upright posture. The orthostatic tachycardia occurs in the absence of orthostatic hypotension and is associated with a >6-month history of symptoms that are relieved by recumbence. The heart rate abnormality and orthostatic symptoms should not be caused by medications that impair autonomic regulation or by debilitating disorders that can cause tachycardia. POTS is a “final common pathway” for a number of overlapping pathophysiologies, including an autonomic neuropathy in the lower body, hypovolemia, elevated sympathetic tone, mast cell activation, deconditioning, and autoantibodies. Not only may patients be affected by more than one of these pathophysiologies, but also the phenotype of POTS has similarities to a number of other disorders, e.g., chronic fatigue syndrome, Ehlers-Danlos Syndrome, vasovagal syncope, and inappropriate sinus tachycardia. POTS can be treated with a combination of non-pharmacological approaches, a structured exercise training program, and often some pharmacological support. PMID:26198889

  18. Fitts' Law in early postural adjustments.

    PubMed

    Bertucco, M; Cesari, P; Latash, M L

    2013-02-12

    We tested a hypothesis that the classical relation between movement time and index of difficulty (ID) in quick pointing action (Fitts' Law) reflects processes at the level of motor planning. Healthy subjects stood on a force platform and performed quick and accurate hand movements into targets of different size located at two distances. The movements were associated with early postural adjustments that are assumed to reflect motor planning processes. The short distance did not require trunk rotation, while the long distance did. As a result, movements over the long distance were associated with substantial Coriolis forces. Movement kinematics and contact forces and moments recorded by the platform were studied. Movement time scaled with ID for both movements. However, the data could not be fitted with a single regression: Movements over the long distance had a larger intercept corresponding to movement times about 140 ms longer than movements over the shorter distance. The magnitude of postural adjustments prior to movement initiation scaled with ID for both short and long distances. Our results provide strong support for the hypothesis that Fitts' Law emerges at the level of motor planning, not at the level of corrections of ongoing movements. They show that, during natural movements, changes in movement distance may lead to changes in the relation between movement time and ID, for example when the contribution of different body segments to the movement varies and when the action of Coriolis force may require an additional correction of the movement trajectory. PMID:23211560

  19. Fitts’ Law in Early Postural Adjustments

    PubMed Central

    Bertucco, M.; Cesari, P.; Latash, M.L

    2012-01-01

    We tested a hypothesis that the classical relation between movement time and index of difficulty (ID) in quick pointing action (Fitts’ Law) reflects processes at the level of motor planning. Healthy subjects stood on a force platform and performed quick and accurate hand movements into targets of different size located at two distances. The movements were associated with early postural adjustments that are assumed to reflect motor planning processes. The short distance did not require trunk rotation, while the long distance did. As a result, movements over the long distance were associated with substantiual Coriolis forces. Movement kinematics and contact forces and moments recorded by the platform were studied. Movement time scaled with ID for both movements. However, the data could not be fitted with a single regression: Movements over the long distance had a larger intercept corresponding to movement times about 140 ms longer than movements over the shorter distance. The magnitude of postural adjustments prior to movement initiation scaled with ID for both short and long distances. Our results provide strong support for the hypothesis that Fitts’ Law emerges at the level of motor planning, not at the level of corrections of ongoing movements. They show that, during natural movements, changes in movement distance may lead to changes in the relation between movement time and ID, for example when the contribution of different body segments to the movement varies and when the action of Coriolis force may require an additional correction of the movement trajectory. PMID:23211560

  20. Postural Tachycardia Syndrome: Beyond Orthostatic Intolerance.

    PubMed

    Garland, Emily M; Celedonio, Jorge E; Raj, Satish R

    2015-09-01

    Postural tachycardia syndrome (POTS) is a form of chronic orthostatic intolerance for which the hallmark physiological trait is an excessive increase in heart rate with assumption of upright posture. The orthostatic tachycardia occurs in the absence of orthostatic hypotension and is associated with a >6-month history of symptoms that are relieved by recumbence. The heart rate abnormality and orthostatic symptoms should not be caused by medications that impair autonomic regulation or by debilitating disorders that can cause tachycardia. POTS is a "final common pathway" for a number of overlapping pathophysiologies, including an autonomic neuropathy in the lower body, hypovolemia, elevated sympathetic tone, mast cell activation, deconditioning, and autoantibodies. Not only may patients be affected by more than one of these pathophysiologies but also the phenotype of POTS has similarities to a number of other disorders, e.g., chronic fatigue syndrome, Ehlers-Danlos syndrome, vasovagal syncope, and inappropriate sinus tachycardia. POTS can be treated with a combination of non-pharmacological approaches, a structured exercise training program, and often some pharmacological support. PMID:26198889

  1. Workers' postural conditions in the charcoal production proccess based on vertical metallic cylynders.

    PubMed

    Maia, Ivana Márcia Oliveira; Francisco, Antonio Carlos de

    2012-01-01

    Considering the importance of posture to the workers' health in the production of charcoal, this paper presents an ergonomic research based on a biomechanical focus that aims to evaluate the posture adopted by these workers on the production of charcoal in vertical metallic cylinders. Thus, it was verified the incidence of pain and/or musculoskeletal injuries to these workers. Also, it was evaluated the weight carried by them and the positions taken in their daily tasks. Applying the Ergonomic Analysis of Labor, the data collection was done by directly observing the workers, registering images, by interviews, and posture analysis based on the OWAS method. The main results of the research show that there are postures with risks in the four levels of musculoskeletal injuries classified by OWAS, concluding that the method is imperative for ergonomic recommendations for minimization or eradication of suffering injury and worker's postural constraints.

  2. The evaluation of body image in children with type 1 diabetes: A case-control study.

    PubMed

    Troncone, Alda; Prisco, Francesco; Cascella, Crescenzo; Chianese, Antonietta; Zanfardino, Angela; Iafusco, Dario

    2016-04-01

    This study evaluated the body image perception in children with type 1 diabetes in order to identify symptoms of disordered eating behaviours early. Children with type 1 diabetes and controls showed underestimation and dissatisfaction with body size. The patients, especially girls, were more accurate in their perception of body size than the control group. The study sheds light on some of the underlying factors that may contribute to the development of disordered eating behaviours in adolescence. The causes of the differences of perception of body size are discussed. PMID:24752557

  3. Guidelines for Creating, Implementing, and Evaluating Mind-Body Programs in a Military Healthcare Setting.

    PubMed

    Smith, Katherine; Firth, Kimberly; Smeeding, Sandra; Wolever, Ruth; Kaufman, Joanna; Delgado, Roxana; Bellanti, Dawn; Xenakis, Lea

    2016-01-01

    Research suggests that the development of mind-body skills can improve individual and family resilience, particularly related to the stresses of illness, trauma, and caregiving. To operationalize the research evidence that mind-body skills help with health and recovery, Samueli Institute, in partnership with experts in mind-body programming, created a set of guidelines for developing and evaluating mind-body programs for service members, veterans, and their families. The Guidelines for Creating, Implementing, and Evaluating Mind-Body Programs in a Military Healthcare Setting outline key strategies and issues to consider when developing, implementing, and evaluating a mind-body focused family empowerment approach in a military healthcare setting. Although these guidelines were developed specifically for a military setting, most of the same principles can be applied to the development of programs in the civilian setting as well. The guidelines particularly address issues unique to mind-body programs, such as choosing evidence-based modalities, licensure and credentialing, safety and contraindications, and choosing evaluation measures that capture the holistic nature of these types of programs. The guidelines are practical, practice-based guidelines, developed by experts in the fields of program development and evaluation, mind-body therapies, patient- and family-centered care, as well as, experts in military and veteran's health systems. They provide a flexible framework to create mind-body family empowerment programs and describe important issues that program developers and evaluators are encouraged to address to ensure the development of the most impactful, successful, evidence-supported programs possible.

  4. Contribution of Head Position, Standing Surface, and Vision to Postural Control in Community-Dwelling Older Adults.

    PubMed

    Pociask, Fredrick D; DiZazzo-Miller, Rosanne; Goldberg, Allon; Adamo, Diane E

    2016-01-01

    Postural control requires the integration of sensorimotor information to maintain balance and to properly position and orient the body in response to external stimuli. Age-related declines in peripheral and central sensory and motor function contribute to postural instability and falls. This study investigated the contribution of head position, standing surface, and vision on postural sway in 26 community-dwelling older adults. Participants were asked to maintain a stable posture under conditions that varied standing surface, head position, and the availability of visual information. Significant main and interaction effects were found for all three factors. Findings from this study suggest that postural sway responses require the integration of available sources of sensory information. These results have important implications for fall risks in older adults and suggest that when standing with the head extended and eyes closed, older adults may place themselves at risk for postural disequilibrium and loss of balance. PMID:26709429

  5. Contribution of Head Position, Standing Surface, and Vision to Postural Control in Community-Dwelling Older Adults.

    PubMed

    Pociask, Fredrick D; DiZazzo-Miller, Rosanne; Goldberg, Allon; Adamo, Diane E

    2016-01-01

    Postural control requires the integration of sensorimotor information to maintain balance and to properly position and orient the body in response to external stimuli. Age-related declines in peripheral and central sensory and motor function contribute to postural instability and falls. This study investigated the contribution of head position, standing surface, and vision on postural sway in 26 community-dwelling older adults. Participants were asked to maintain a stable posture under conditions that varied standing surface, head position, and the availability of visual information. Significant main and interaction effects were found for all three factors. Findings from this study suggest that postural sway responses require the integration of available sources of sensory information. These results have important implications for fall risks in older adults and suggest that when standing with the head extended and eyes closed, older adults may place themselves at risk for postural disequilibrium and loss of balance.

  6. Quantifying and Reducing Posture-Dependent Distortion in Ballistocardiogram Measurements

    PubMed Central

    Javaid, Abdul Q.; Wiens, Andrew D.; Fesmire, N. Forrest; Weitnauer, Mary A.; Inan, Omer T.

    2015-01-01

    Ballistocardiography is a non-invasive measurement of the mechanical movement of the body caused by cardiac ejection of blood. Recent studies have demonstrated that ballistocardiogram (BCG) signals can be measured using a modified home weighing scale, and used to track changes in myocardial contractility and cardiac output. With this approach, the BCG can potentially be used both for preventive screening and for chronic disease management applications. However, for achieving high signal quality, subjects are required to stand still on the scale in an upright position for the measurement; the effects of intentional (for user comfort) or unintentional (due to user error) modifications in the position or posture of the subject during the measurement have not been investigated in the existing literature. In this study, we quantified the effects of different standing and seated postures on the measured BCG signals, and on the most salient BCG-derived features compared to reference standard measurements (e.g., impedance cardiography). We determined that the standing upright posture led to the least distorted signals as hypothesized, and that the correlation between BCG-derived timing interval features (R-J interval) and the pre-ejection period, PEP (measured using ICG), decreased significantly with impaired posture or sitting position. We further implemented two novel approaches to improve the PEP estimates from other standing and sitting postures, using system identification and improved J-wave detection methods. These approaches can improve the usability of standing BCG measurements in unsupervised settings (i.e. the home), by improving the robustness to non-ideal posture, as well as enabling high quality seated BCG measurements. PMID:26058064

  7. Development of Postural Control in Healthy Children: A Functional Approach

    PubMed Central

    Assaiante, Christine; Mallau, Sophie; Viel, Sébastien; Jover, Marianne; Schmitz, Christina

    2005-01-01

    From a set of experimental studies showing how intersegmental coordination develops during childhood in various posturokinetic tasks, we have established a repertoire of equilibrium strategies in the course of ontogenesis. The experimental data demonstrate that the first reference frame used for the organization of balance control during locomotion is the pelvis, especially in young children. Head stabilization during posturokinetic activities, particularly locomotion, constitutes a complex motor skill requiring a long time to develop during childhood. When studying the emergence of postural strategies, it is essential to distinguish between results that can be explained by biomechanical reasons strictly and those reflecting the maturation of the central nervous system (CNS). To address this problem, we have studied our young subjects in situations requiring various types of adaptation. The studies dealing with adaptation of postural strategies aimed at testing short and long-term adaptation capacity of the CNS during imposed transient external biomechanical constraints in healthy children, and during chronic internal constraints in children with skeletal pathologies. In addition to maintenance of balance, another function of posture is to ensure the orientation of a body segment. It appears that the control of orientation and the control of balance both require the trunk as an initial reference frame involving a development from egocentric to exocentric postural control. It is concluded that the first step for children consists in building a repertoire of postural strategies, and the second step consists in learning to select the most appropriate postural strategy, depending on the ability to anticipate the consequence of the movement in order to maintain balance control and the efficiency of the task. PMID:16097479

  8. A Simple Postflight Measure of Postural Atania in Astronauts

    NASA Technical Reports Server (NTRS)

    Reschke, M. F.; Harm, D. I.; Kofman, I. S.; Wood, S. J.; Bloomberg, J. J.

    2011-01-01

    Astronauts returning from space flight universally present with postural ataxia. Throughout the Space Shuttle Program, measurement of ataxia has concentrated on sway in the anterior-posterior (AP) plane. The current investigation, as a part of a larger functional study, concentrated on characterizing postural instability using dynamic stabilographic sway patterns in both the AP and medial-lateral (ML) planes. To accomplish this goal, six astronauts from short-duration (Shuttle) and three from long-duration (ISS) flights were required to recover from a simulated fall. Subjects with eyes open, wearing running shoes lay prone on the floor for 2 minutes and then quickly stood up, maintained a quiet stance for 3 minutes, arms relaxed along the side of the body, and feet comfortably placed on the force plate. Crewmembers were tested twice before flight, on landing day (Shuttle only), and 1, 6, and 30 days after flight. Anterior-posterior and ML center-of-pressure (COP) coordinates were calculated from the ground reaction forces collected at 500 Hz. The 3-minute quiet stance trial was broken into three 1-minute segments for stabilogram diffusion analysis. A mean sway speed (rate of change of COP displacement) was also calculated as an additional postural stability parameter. While there was considerable variation, most of crewmembers tested exhibited increased stochastic activity evidenced by larger short-term COP diffusion coefficients postflight in both the AP and ML planes, suggesting significant changes in postural control mechanisms, particularly control of lower limb muscle function. As expected, postural instability of ISS astronauts on the first day postflight was similar to that of Shuttle crewmembers on landing day. Recoveries of stochastic activity and mean sway speed to baseline levels were typically observed by the 30th day postflight for both long-duration and short-duration crewmembers. Dynamic postural stability characteristics obtained in this low

  9. Development and initial validation of the Seated Posture Scale.

    PubMed

    Barks, Lelia; Luther, Stephen L; Brown, Lisa M; Schulz, Brian; Bowen, Mary Elizabeth; Powell-Cope, Gail

    2015-01-01

    Literature shows that some health outcomes (e.g., eating, breathing, and speaking) are directly related to posture. Evidence of outcomes mediated by wheelchair seated posture is limited to interface pressure, physical function, and wheelchair skills and safety. This study's purpose was to develop and validate a rapid, low-burden, paper-pencil assessment of wheelchair seated posture for research use and to test feasibility of its use with a sample of older adults. We used a prospective design and a convenience sample of older adults who were receiving rehabilitation services in a community living center. Forty-nine older wheelchair users participated. Main measures were the Seated Posture Scale (SPS), Modified Ashworth Scale, Barthel Index, Visual Descriptor Scale, scale-content validity index (S-CVI), Cronbach alpha, and test-retest reliability. Rating by six experts yielded the overall content validity score (S-CVI) of 0.744. Total SPS score correlated positively with physical function (Barthel Index, r = 0.46, p < 0.001) and negatively with muscle tone (Modified Ashworth Scale, r = -0.44, p = 0.001), supporting SPS construct validity. Internal consistency was 0.66 (Cronbach alpha). Test-retest reliability yielded Pearson product-moment correlations of 0.89 to 0.99. We conclude that the SPS has sufficient preliminary validity and reliability to support its use as an evaluation of wheelchair seated posture in outcomes research. PMID:26230339

  10. Age Related Decline in Postural Control Mechanisms.

    ERIC Educational Resources Information Center

    Stelmach, George E.; And Others

    1989-01-01

    Studied voluntary and reflexive mechanisms of postural control of young (N=8) and elderly (N=8) adults through measurement of reflexive reactions to large-fast and small-slow ankle rotation postural disturbances. Found reflexive mechanisms relatively intact for both groups although elderly appeared more disadvantaged when posture was under the…

  11. Early recognition of postural disorders in multiple sclerosis through movement analysis: a modeling study.

    PubMed

    Corradini, M L; Fioretti, S; Leo, T; Piperno, R

    1997-11-01

    In the present study, spontaneous postural behavior has been analyzed in freely standing multiple sclerosis (MS)