The effect of simultaneously and sequentially delivered cognitive and aerobic training on mobility among older adults with hearing loss.

Background: Older adults exhibit declines in auditory and motor functioning, which are compensated for through the recruitment of cognitive resources. Cognitive or physical training alone has been shown to improve cognitive functioning and transfer to motor tasks, but results are mixed when these are combined in studies of healthy older adults, and few studies have included those with age-related hearing loss (ARHL), who are at a higher risk of falls.

Research Question: To examine format effects in mixed training, we used a repeated measures intervention design to compare the efficacy of Simultaneous and Sequential multimodal training formats.

Test-retest reliability of a balance testing protocol with external perturbations in young healthy adults.

External perturbations are utilized to challenge balance and mimic realistic balance threats in patient populations. The reliability of such protocols has not been established. The purpose was to examine test-retest reliability of balance testing with external perturbations.

The Effects of Age and Hearing Loss on Dual-Task Balance and Listening.

Objectives: Among older adults (OA), hearing loss is associated with an increased risk for falls. The aim of the present study was to experimentally investigate the cognitive compensation hypothesis, wherein decreased auditory and motor functioning are compensated by the recruitment of cognitive resources.

Method: Twenty-nine younger adults (YA), 26 OA, and 32 OA with age-related hearing loss (ARHL) completed a dual-task paradigm consisting of cognitive and balance recovery tasks performed singly and concurrently.

Integration of active pauses and pattern of muscular activity during computer work.

Submaximal isometric muscle contractions have been reported to increase variability of muscle activation during computer work; however, other types of active contractions may be more beneficial. Our objective was to determine which type of active pause vs. rest is more efficient in changing muscle activity pattern during a computer task.

Kinematics and muscle activation patterns during a maximal voluntary rate activity in healthy elderly and young adults.

Background: Maximal voluntary rate (MVR) performance tasks can provide important age-related information to the limiting factors associated with movement and the development of fatigue.

Aim: To determine whether kinematic and muscle activation patterns during an MVR task differ between young and older adults.

Methods: We continuously measured frequency, amplitude, peak velocity, index of co-contraction and median frequencies of the index finger flexors and extensors during a 20-s MVR task in 10 young and 10 older subjects.

Unilateral eccentric exercise of the knee flexors affects muscle activation during gait.

Uni-lateral muscle soreness is common yet the effects on gait or electromyographic (EMG) activity are unknown. The purpose of our study was to induce delayed onset muscle soreness (DOMS) in the knee flexor group and measure the resultant change in EMG activity and knee motion during gait. Nine healthy subjects participated in the study.

Direction-dependent neck and trunk postural reactions during sitting.

Postural reactions in healthy individuals in the seated position have previously been described and have been shown to depend on the direction of the perturbation; however the neck response following forward and backward translations has not been compared. The overall objective of the present study was to compare neck and trunk kinematic, kinetic and electromyographic (EMG) stabilization patterns of seated healthy individuals to forward and backward translations. Ten healthy individuals, seated on a chair fixed onto a movable platform, were exposed to forward and backward translations (distance=0.

A paradigm to assess postural responses triggered by anteroposterior translations in healthy seated individuals.

Postural adjustments following mechanical perturbations have been studied in healthy seated humans. However, little is known on the minimal intensity that should be used to provoke a reaction. This knowledge could be essential to assess seated postural deficits in some pathological populations.

Whiplash-associated disorders affect postural reactions to antero-posterior support surface translations during sitting.

Previous studies have shown that individuals with WAD display decreased postural stability during standing and walking tasks. However, their ability to maintain seated upright posture has never been investigated. The objective of this study was to characterize kinematic and electromyographic postural stabilization patterns in individuals with chronic WAD and to compare these patterns with those in an able-bodied control group.

A reproducible method for studying three-dimensional knee kinematics.

The methods used in movement analysis often rely on the definition of joint coordinate systems permitting three-dimensional (3D) kinematics. The first aim of this research project was to present a functional and postural method (FP method) to define a bone-embedded anatomical frame (BAF) on the femur and tibia, and, subsequently, a knee joint coordinate system. The repeatability of the proposed method was also assessed.

Effect of ski binding parameters on knee biomechanics: a three-dimensional computational study.

Introduction: Downhill skiing is a relatively safe sport, but many potentially avoidable injuries do occur. Whereas tibia and ankle injuries have been declining, severe knee sprains usually involving the anterior cruciate ligament (ACL) have increased from the 1970s to the 1990s. The goal of the present study was to evaluate the effect of the position of the binding pivot point and binding release characteristics on ACL strain during a phantom-foot fall.

Referent configuration of the body: a global factor in the control of multiple skeletal muscles.

In addition to local biomechanical and reflex factors influencing muscle activation, global factors may be used by the nervous system to control all muscles in a coherent and task-specific way. It has been hypothesized that a virtual or referent (R) configuration of the body determined by muscle recruitment thresholds specified by neural control levels is such a factor. Due to the threshold nature of the R configuration, the activity of each muscle depends on the difference between the actual (Q) and the R configuration of the body.

The hygienist's role in improving children's oral health throughout their development.

Improving oral hygiene in children is one of the most challenging aspects of the preventive dental practice because their dentition, dexterity, and emotional maturity are simultaneously developing. This article discusses the role of the hygienist in providing oral health care and education in the context of developing preventive care programs that can be tailored to meet the needs of children in different age groups. Particular attention will be given to identifying proven approaches to motivating children and their parents to respond positively to oral health advice and hygiene instruction.

Interjoint coordination in lower limbs during different movements in humans.

Redundancy is associated with the ability of the nervous system to select different interjoint coordinations and movement trajectories to achieve the same motor goal. The nervous system may coordinate multiple degrees of freedom (DF) by combining them in a task-specific way to control them as a unit or synergy. Some movements may be accomplished using only one synergy, whereas other movements may employ several synergies.