Estimation of centre of gravity movements in sitting posture: application to trunk backward tilt.
Summary of "Estimation of centre of gravity movements in sitting posture: application to trunk backward tilt."
The aim of this study was to highlight, in sitting posture, the value of distinguishing between the movements of the vertical projection of the centre of gravity (CG(v)) and its difference from the centre of pressure (CP-CG(v)). A protocol for healthy, young, trained adults, consisting in tilting their trunk backward or keeping it vertical was used. A frequency analysis shows that statistically significant effects were only seen on CP-CG(v) movements: the RMS increased by 37% (p=0.004), while the MPF decreased by 5% (p=0.016), suggesting an increased muscular activity in these tilting postures. In contrast, no statistically significant effects on CP and CG(v) were reported. These data highlight the advantage, in sitting posture, of splitting overall CP displacements into basic components (i.e. CG(v) and CP-CG(v)), each of them having a biomechanical significance.
Université de Savoie, Domaine scientifique de Savoie-Technolac, Laboratoire de Physiologie de l'Exercice-EA4338, 73376 Le-Bourget-du-Lac, France.
This article was published in the following journal.
Name: Journal of biomechanics
- PubMed Source: http://www.ncbi.nlm.nih.gov/pubmed/21549381
- DOI: http://dx.doi.org/10.1016/j.jbiomech.2011.04.008
Medical and Biotech [MESH] Definitions
A POSTURE in which an ideal body mass distribution is achieved. Postural balance provides the body carriage stability and conditions for normal functions in stationary position or in movement, such as sitting, standing, or walking.
Freezing Reaction, Cataleptic
An induced response to threatening stimuli characterized by the cessation of body movements, except for those that are involved with BREATHING, and the maintenance of an immobile POSTURE.
Process whereby a cell, bodily structure, or organism (animal or plant) receives or detects a gravity stimulus. Gravity sensing plays an important role in the directional growth and development of an organism (GRAVITROPISM).
Abnormal movements, including HYPERKINESIS; HYPOKINESIA; TREMOR; and DYSTONIA, associated with the use of certain medications or drugs. Muscles of the face, trunk, neck, and extremities are most commonly affected. Tardive dyskinesia refers to abnormal hyperkinetic movements of the muscles of the face, tongue, and neck associated with the use of neuroleptic agents (see ANTIPSYCHOTIC AGENTS). (Adams et al., Principles of Neurology, 6th ed, p1199)
An attitude or posture due to the co-contraction of agonists and antagonist muscles in one region of the body. It most often affects the large axial muscles of the trunk and limb girdles. Conditions which feature persistent or recurrent episodes of dystonia as a primary manifestation of disease are referred to as DYSTONIC DISORDERS. (Adams et al., Principles of Neurology, 6th ed, p77)
The purpose of this study was to assess trunk muscle fatigue in seated handicraft tasks using surface electromyography (sEMG) and visual analogue scale (VAS) ratings for trunk discomfort, and to asses...
Sitting is a common aggravating factor in low back pain (LBP), and re-education of sitting posture is a common aspect of LBP management. However, there is debate regarding what is an optimal sitting p...
Purpose. To investigate the feasibility of using pressure mapping for the characterisation of the seated posture of children with cerebral palsy (CP). Method. Analysis of pressure mapping readings and...
Closed-loop (CL) and open-loop (OL) types of motor control during human forward upper trunk bending are investigated. A two-joint (hip and ankle) biomechanical model of the human body is used. The ana...
Analyzing an athlete's "technique," sport scientists often focus on preselected variables that quantify important aspects of movement. In contrast, coaches and practitioners typically describe movemen...
To determine if sitting in a chair or sitting on the floor lends itself to better posture while playing video games.
The aim of this study was to identify posture asymmetries in transfemoral amputees utilizing clinical evaluation measures. The purposes of this investigation were: 1) to measure the limb...
This study is designed to investigate the effect of body posture (particularly when sleeping) on the pressure in the eye. The effect of body posture on progressive glaucoma (glaucoma where...
The purpose of this study is to verify that nebulization with bronchodilators associated with heliox gas (helium + oxygen) and the posture of a leaning forward truck is effective in patien...
Older adults with a disability tend to spend greater periods of time in bed each day and often over a mealtime. To make it safe for them to eat in bed, the patient is placed in a high Fowl...