Reliability of a 2D-Panoramic Ultrasound System for the Determination of Muscle Volume in Older Hospitalized Patients.

Reliability of muscle thickness assessed in B-mode ultrasound has been confirmed in adults but remains a less direct assessment of muscle mass than muscle volume (MV). The aim of this prospective monocentric study was to assess the interday reliability of MV determined by the 2D-panoramic ultrasound in older hospitalized patients.Ten participants hospitalized in geriatric ward (mean age = 84) underwent 2 sessions of panoramic ultrasound scanning 1 week apart for MV assessment and DXA for leg lean mass (LLM) assessment when it was possible.

Supporting every school to become a foundation for healthy lives.

As a setting where children and adolescents live and learn, linked to the family and embedded within the wider community, schools have an important influence on every student's health. Many health interventions have used schools as a platform, often for standalone programmatic initiatives to reduce health risks, and sometimes for more comprehensive approaches, but the interventions, uptake, and sustainability are generally disappointing. Evidence shows that, to improve health and to reduce inequality, all students must attend school from a young age and for as long as possible, and their educational success therein must be maximised.

Acute effect of tendon vibration applied during isometric contraction at two knee angles on maximal knee extension force production.

The aim of the current study was to investigate the effect of a single session of prolonged tendon vibration combined with low submaximal isometric contraction on maximal motor performance. Thirty-two young sedentary adults were assigned into two groups that differed based on the knee angle tested: 90° or 150° (180° = full knee extension). Participants performed two fatigue-inducing exercise protocols: one with three 10 min submaximal (10% of maximal voluntary contraction) knee extensor contractions and patellar tendon vibration (80 Hz) another with submaximal knee extensor contractions only.

Is there an intermuscular relationship in voluntary activation capacities and contractile kinetics?

Purpose: The force-generating capacities of human skeletal muscles are interrelated, highlighting a common construct of limb strength. This study aimed to further determine whether there is an intermuscular relationship in maximal voluntary activation capacities and contractile kinetics of human muscles.

Methods: Twenty-six young healthy individuals participated in this study.

Perceptual Inhibition Is Not a Specific Component of the Sensory Integration Process Necessary for a Rapid Voluntary Step Initiation in Healthy Older Adults.

Objectives: We investigated whether performing step initiation during a proprioceptive perturbation would require greater perceptual or motor inhibitory control in older adults.

Method: Fifty-two healthy adults (young: n = 26, mean age 22.5 years vs.

Neural and muscular factors both contribute to plantar-flexor muscle weakness in older fallers.

Plantar-flexor muscles are key muscles in the control of postural sway. Older fallers present lower maximal plantar-flexor performance than older non-fallers; however, the mechanisms underlying this motor impairment remain to be elucidated. This study aimed to determine whether muscular and neural factors are both involved in the lower maximal plantar-flexor performance of older fallers.

Effect of knee angle on neuromuscular assessment of plantar flexor muscles: A reliability study.

Introduction: This study aimed to determine the intra- and inter-session reliability of neuromuscular assessment of plantar flexor (PF) muscles at three knee angles.

Methods: Twelve young adults were tested for three knee angles (90°, 30° and 0°) and at three time points separated by 1 hour (intra-session) and 7 days (inter-session). Electrical (H reflex, M wave) and mechanical (evoked and maximal voluntary torque, activation level) parameters were measured on the PF muscles.

Can Methodological Considerations Challenge the Dissociation of the Perceptual and Motor Inhibitory Processes?

Using an original conflict task paradigm, Nassauer and Halperin (2003) argued that inhibition ability can be classified into two distinct perceptual and motor inhibitory processes. The current study examined the robustness of this paradigm by raising two major methodological points: the amount of information that needs to be processed and the task order (fixed vs. random).

Examination of reactive motor responses to Achilles tendon vibrations during an inhibitory stepping reaction time task.

Inhibition is known to influence balance, step initiation and gait control. A specific subcomponent of inhibition, the perceptual inhibition process, has been suggested to be specifically involved in the integration of proprioceptive information that is necessary for efficient postural responses. This study aimed to investigate the inhibition requirements of planning and executing a choice step initiation task in young adults following experimental perturbation of proprioceptive information using Achilles tendon vibrations.

H-reflex and M-wave recordings: effect of pressure application to the stimulation electrode on the assessment of evoked potentials and subject's discomfort.

This study aimed to compare the effect of different types of pressure applied to the stimulation electrode on assessing the efficiency of Ia-α-motoneuron transmission of the soleus muscle and the associated discomfort using electrical nerve stimulation. Twelve healthy young adults participated in three experimental sessions (one for each knee angle). The amplitudes of the maximal Hoffmann reflex (H ) and motor potential (M ) were recorded from the soleus muscle at 0°, 30° and 90° knee angles (0° full extension) through three pressure applications to the stimulation electrode: no pressure, pressure with manual application and pressure using adhesive tape.

Comparison of two methodological approaches for the mechanical analysis of single-joint isoinertial movement using a customised isokinetic dynamometer.

Compared to isokinetic and isometric tests, isoinertial movements have been poorly used to assess single-joint performance. Two calculation procedures were developed to estimate mechanical performance during single-joint isoinertial movements performed on a customised isokinetic dynamometer. The results were also compared to appreciate the effects of measurement systems and calculation procedures.

Changes in elbow joint's musculo-articular mechanical properties do not alter reaching-related action-perception coupling.

Purpose: Perception of action capabilities can be altered by changes in sensorimotor processes, as showed in previous works in populations dealing with regular and pathological sensorimotor deficits. Misestimating changes in performance ability could lead to risky behavior, injury, and/or reduced performance. However, the relationship between sensorimotor processes, the action-perception coupling, and the related anatomical structures is still a matter of debate.

I can't reach it! Focus on theta sensorimotor rhythm toward a better understanding of impaired action-perception coupling.

It is known that anxiety (ANX) impairs action-perception coupling. This study tests whether this impairment could be associated with an alteration of the sensorimotor function. To this aim, the cortical activities underlying the sensorimotor function were recorded in twelve volunteers in a reach-to-grasp paradigm, in which the level of ANX and the position of a glass were manipulated.

No Alteration of the Neuromuscular Performance of Plantar-Flexor Muscles After Achilles Tendon Vibration.

Context: Prolonged tendon vibration may induce muscle fatigue, as assessed by a decrease in maximal force production. It remains unknown, however, whether the decrease in muscle strength after prolonged Achilles tendon vibration is related to the vibration frequency. Objective: To assess the maximal capacity of plantar-flexor (PF) neuromuscular function before and after prolonged Achilles tendon vibration at low and high frequencies generated using a portable device.

A decision model to predict the risk of the first fall onset.

Background: Miscellaneous features from various domains are accepted to be associated with the risk of falling in the elderly. However, only few studies have focused on establishing clinical tools to predict the risk of the first fall onset. A model that would objectively and easily evaluate the risk of a first fall occurrence in the coming year still needs to be built.

[What are the effects of the aging of the neuromuscular system on postural stability?].

Aging is frequently associated with a decreased postural stability, essentially after 60 years, leading to an increased risk of falling. In this article we propose to highlight the influence of the aging of the neuromuscular system on postural stability when standing upright. To maintain balance while standing upright, human needs to control the activity of ankle muscles and particularly the plantar flexors.

Sit to stand in elderly fallers vs non-fallers: new insights from force platform and electromyography data.

Background: The sit-to-stand movement requires balance control and coordination between the trunk and lower limbs. For these reasons, it is commonly used in clinics for evaluating lower limb muscle function in the elderly. The aim of the present study was to point out re levant biomechanical and neurophysiological sit-to-stand parameters allowing comparison between elderly fallers and non-fallers.

Neuromuscular electrical stimulation leads to physiological gains enhancing postural balance in the pre-frail elderly.

Physiological aging leads to a progressive weakening of muscles and tendons, thereby disturbing the ability to control postural balance and consequently increasing exposure to the risks of falls. Here, we introduce a simple and easy-to-use neuromuscular electrical stimulation (NMES) training paradigm designed to alleviate the postural control deficit in the elderly, the first hallmarks of which present as functional impairment. Nine pre-frail older women living in a long-term care facility performed 4 weeks of NMES training on their plantarflexor muscles, and seven nontrained, non-frail older women living at home participated in this study as controls.

Determination of reliable force platform parameters and number of trial to evaluate sit-to-stand movement.

Background: Sit-to-stand (STS) movement is useful for evaluating lower limb muscle function, especially from force platforms. Nevertheless, due to a lack of standardization of the STS movement (e.g.

Time-course of performance changes and underlying mechanisms during and after repetitive moderately weight-loaded knee extensions.

The purpose of this study was to investigate the mechanisms of fatigue development induced by isoload (IL) fatiguing knee extensions. Nine physically active males (age=23±2years, height=179±7cm, mass=76±7kg) performed repetitive ballistic knee extensions at 30% of the isometric maximal voluntary peak torque. Fatigue development was assessed throughout the fatiguing exercise by quantifying changes in peak torque, agonist and antagonist electromyographic activity (EMG) and torque- and EMG-angle relationships.

An enhanced experimental procedure to rationalize on the impairment of perception of action capabilities.

It is well documented that changes in the physiological states of the perceiver-actor influence the perception of action capabilities. However, because experimental procedures of most studies involved a limitless availability for stimuli visual encoding and perceptual strategies, it remains difficult to adopt a single position among the large range of alternative interpretations for impaired perception. A reaching-to-grasp paradigm under breathing restriction was adapted from Graydon et al.

Muscle and tendon stiffness assessment using the alpha method and ultrafast ultrasound.

Purpose: The alpha method enables the dissociation of the passive (i.e., tendinous tissues) and active (i.

Effects of total sleep deprivation on the perception of action capabilities.

Changes in a subject's state have been shown to modulate the perceptual update of his or her action capabilities. In parallel, sleep deprivation impairs in cognitive functions. It involves common neural structures that support the perception of successfully achieving a motor task.