Validation of a 3D Markerless Motion Capture Tool Using Multiple Pose and Depth Estimations for Quantitative Gait Analysis.

Gait analysis is essential for evaluating walking patterns and identifying functional limitations. Traditional marker-based motion capture tools are costly, time-consuming, and require skilled operators. This study evaluated a 3D Marker-less Motion Capture (3D MMC) system using pose and depth estimations with the gold-standard Motion Capture (MOCAP) system for measuring hip and knee joint angles during gait at three speeds (0.

Assessing muscle quality as a key predictor to differentiate fallers from non-fallers in older adults.

Background: Falling is an important public health issue because of its prevalence and severe consequences. Evaluating muscle performance is important when assessing fall risk. The study aimed to identify factors [namely muscle capacity (strength, quality, and power) and spatio-temporal gait attributes] that best discriminate between fallers and non-fallers in older adults.

Spatial Contextual Information Modulates Affordance Processing and Early Electrophysiological Markers of Scene Perception.

Scene perception allows humans to extract information from their environment and plan navigation efficiently. The automatic extraction of potential paths in a scene, also referred to as navigational affordance, is supported by scene-selective regions (SSRs) that enable efficient human navigation. Recent evidence suggests that the activity of these SSRs can be influenced by information from adjacent spatial memory areas.

Age-related effects on absolute and relative isokinetic knee extensor strength in community-dwelling older men and women at a French geriatric day hospital.

Purpose: Isokinetic knee extensor strength is poorly evaluated in geriatric day hospitals (GDHs), despite its potential functional significance compared to grip strength. This study aimed to investigate age-related effects on absolute and relative isokinetic knee extensor peak torque (KEPT) data in community-dwelling older GDH patients.

Methods: A total of 472 French GDH patients (179 men and 293 women, aged 75-94 years) participated in this study.

How does apathy impact exploration-exploitation decision-making in older patients with neurocognitive disorders?

Apathy is a pervasive clinical syndrome in neurocognitive disorders, characterized by a quantitative reduction in goal-directed behaviors. The brain structures involved in the physiopathology of apathy have also been connected to the brain structures involved in probabilistic reward learning in the exploration-exploitation dilemma. This dilemma in question involves the challenge of selecting between a familiar option with a more predictable outcome, and another option whose outcome is uncertain and may yield potentially greater rewards compared to the known option.

Effect of a sex stereotype on cortical activity during a self-paced exercise: A motor-related cortical potential approach.

Recent research has shown that inducing a negative stereotype toward women does not always decrease the subsequent motor performance of women, but can increase it, especially during endurance tasks. The mechanisms involved are nonetheless still poorly understood. The main aim of the present study was to investigate the effect of a negative stereotype toward women on men's and women's performance during an endurance task, and to analyze the neuropsychological mechanisms involved through motor-related cortical potentials and motivation toward men/women.

Effects of individualized lower limb isokinetic strengthening in clinical rehabilitation of older post-stroke patients: A retrospective study.

Objective: Muscle weakness in the lower limbs is a motor consequence of stroke that causes functional impairment. The aim of this study was to assess the effectiveness of an individualized isokinetic strengthening programme, using the moment-velocity profile, on functional recovery during post-stroke rehabilitation of older patients. A further objective was to describe the effects of the individualized isokinetic strengthening on muscular parameters.

Effects of muscular and mental fatigue on spatiotemporal gait parameters in dual task walking in young, non-frail and frail older adults.

Background: Dual-task (DT) walking is of great interest in clinical evaluation to evaluate frailty or cognitive declines in older adults. Frail older adults are known to adopt different walking strategy to overcome fatigue. However, no studies evaluated the effect of muscular or mental fatigue on dual-task walking strategy and the difference between frail and non-frail older adults.

Validation of 3D Knee Kinematics during Gait on Treadmill with an Instrumented Knee Brace.

To test a novel instrumented knee brace intended for use as a rehabilitation system, based on inertial measurement units (IMU) to monitor home-based exercises, the device was compared to the gold standard of motion analysis. The purpose was to validate a new calibration method through functional tasks and assessed the value of adding magnetometers for motion analysis. Thirteen healthy young adults performed a 60-second gait test at a comfortable walking speed on a treadmill.

Effects of age, sex, frailty and falls on cognitive and motor performance during dual-task walking in older adults.

Background: Dual-task (DT) walking is of great interest in clinical evaluation to evaluate the risk of falling or cognitive declines in older adults. However, it appears necessary to investigate deeply the confounding factors to better understand their impact on dual-task performance.

Objective: To evaluate the effect of age, sex, falls and frailty on cognitive and motor parameters in dual-task walking.

A kinematic-geometric model based on ankles' depth trajectory in frontal plane for gait analysis using a single RGB-D camera.

The emergence of RGB-D cameras and the development of pose estimation algorithms offer opportunities in biomechanics. However, some challenges still remain when using them for gait analysis, including noise which leads to misidentification of gait events and inaccuracy. Therefore, we present a novel kinematic-geometric model for spatio-temporal gait analysis, based on ankles' trajectory in the frontal plane and distance-to-camera data (depth).

Impact of a Wearable Activity Tracker on Disease Flares in Spondyloarthritis: A Randomized Controlled Trial.

Objective: To evaluate the impact of a wearable activity tracker used to encourage physical activity, on disease flares in patients with spondyloarthritis (SpA).

Methods: This randomized controlled trial involved randomizing 108 patients with SpA into tracker and nontracker groups. The participants were then subjected to assessments of disease activity, performance (6-minute walk test), and quality of life (QOL; 36-item Short Form Health Survey) at the 12th, 24th, and 36th week.

Apathetic patients with neurocognitive disorders are more fatigued and fatigable.

Background: Apathy is common in neurocognitive disorders (NCD) and manifests as reduced goal-directed behaviors and activities. A decrease in everyday activities can also be due to fatigue, another common symptom in NCD. The aim of this study was to investigate if apathetic patients with NCD are more fatigued and more fatigable.

Associations, overlaps and dissociations between apathy and fatigue.

Apathy and fatigue have a high prevalence in many pathological populations, but they are also present in healthy adults. The relationship between apathy and fatigue, which are both multidimensional, is still poorly understood. This study aims to describe the associations between the subdimensions of both apathy and fatigue and to investigate their overlaps and dissociations in healthy people.

The effect of different dual tasks conditions on gait kinematics and spatio-temporal walking parameters in older adults.

Background: Dual-task (DT) walking has increasingly been investigated over the last decade because of its valuable role as a clinical marker of both cognitive impairment and fall risk in older adults based on cognitive and motor performance (DTEcog, DTEmotor). However, there is still a lack of information on what type of dual task to choose and which is the most adapted to the population of interest.

Research Question: To evaluate the effect of different dual-tasks (DT3, DT7, FLU, STROOP) on the spatiotemporal and kinematic parameters of hip, knee, and ankle joints.

How fiber dynamics of plantarflexor and dorsiflexor muscles based on EMG-driven approach can explain the metabolic cost at different gait speeds.

Purpose: The aim of this study was to investigate the fiber dynamics of plantarflexor and dorsiflexor muscles and their association with the net metabolic rate (NC).

Methods: Metabolic, kinematic, kinetic, and electromyography measurements were made on seven young subjects while they walked on a force-plate instrumented treadmill at 1.00, 1.

6MWT on a new self-paced treadmill system compared with overground.

The 6-min walk test (6MWT) is a useful tool for clinicians and researchers to estimate gait performance and fatigue affecting functional mobility. A modified 6MWT administered on a treadmill (TM) can be an efficient, space-saving alternative to perform the 6MWT. The aim of this study was to investigate if a 6MWT on a self-paced (SP) TM produced similar results compared to an overground (OG) 6MWT among healthy participants with the hypothesis that users would demonstrate similar gait parameters.

Metabolic cost and co-contraction during walking at different speeds in young and old adults.

Background: The net metabolic cost of walking (NCw) and the co-activation of leg muscles are both higher in old adults (OG) than in young adults (YG). Nevertheless, the relation between the two remains unresolved, mainly due to the controversial co-activation measurement method used in previous studies.

Research Question: To compare ankle and knee co-contraction (CCI), calculated using an EMG-driven method, between the groups and to examine their relationship with NCw.

Validity of a simple sit-to-stand method for assessing force-velocity profile in older adults.

Background: Lower limb muscle strength is an important determinant of physical function in older adults. However, its measure in clinical settings is limited because of the requirement for large-scale and costly equipment. A new simple protocol based on sit-to-stand test (STS) is developed to measure force velocity (F-v) and power velocity (P-v) profile in the community-dwelling older adults.

Does the Effect of Stereotypes in Older People Depend Upon Task Intensity?

This study examined the effect of negative and positive stereotypes on the strength produced by older adults at different perceived effort intensities, reflecting different levels of task difficulty. Fifty older women were randomly assigned to a positive stereotype, a negative stereotype, or a control condition. Before (T1) and after (T2) the stereotype manipulation, they were asked to perform a voluntary isometric contraction at a level of muscular effort that corresponded to four perceived effort intensities ("easy," "moderate," hard" and "very hard").

Single-session training on an ascending treadmill slope: effects on gait parameters in persons with stroke. A pilot study.

Objective: Treadmill training with an upward incline could improve gait parameters altered in persons with stroke, especially lower limb flexion. This study aimed to determine the effects of a treadmill single-session training with a 10% upward incline on biomechanical gait parameters in persons with stroke.

Methods: Fifteen persons with stroke-related hemiparesis performed a 20-min treadmill training session with a 10% ascending incline in this interventional pilot study.

Effects of age, gender, frailty and falls on spatiotemporal gait parameters: a retrospective cohort study.

Background: Many studies have explored spatial and temporal gait parameters in the elderly, and showed that frailty status, fall history, age, and gender may individually strongly influence these parameters. However, it appears necessary to investigate the confounding factors more deeply in order to better know the specific role of each of these factors impacting the evolution of gait with the increase of age.

Aim: The aim of the present study was to determine the influence of frailty status, fall history, age and gender on spatiotemporal gait parameters.

Relationship between personality and physical capacities in older adults: The mediating role of subjective age, aging attitudes and physical self-perceptions.

Walking speed and muscular strength are two main markers of health in adulthood. Previous studies have shown that personality traits may predict these two outcomes. However, little is known about the mechanisms underlying these relationships.

Sonoelastography to Assess Muscular Stiffness Among Older Adults and its Use for the Diagnosis of Sarcopenia: A Systematic Review.

Changes in muscle stiffness have been reported with sarcopenia. Sonoelastography is an accessible and non-radiating imaging technique allowing quantification of elastic properties of tissue. We performed a systematic review of the literature to investigate whether sonoelastography can be a reliable method to assess sarcopenia in older patients.

Self-rehabilitation combined with botulinum toxin to improve arm function in people with chronic stroke. A randomized controlled trial.

Background: Botulinum toxin injection (BTI) reduces muscle hyperactivity, but its effect on active upper-limb function is limited. Intensive rehabilitation could optimize the effects; however, outpatient post-stroke rehabilitation is usually not intensive. One solution could be self-rehabilitation.