Tablet-based strength-balance training to motivate and improve adherence to exercise in independently living older people: A phase II preclinical exploratory trial

Background: Reaction time, coordination, and cognition performance typically diminish in older adults, which may lead to gait impairments, falls, and injuries. Regular strength-balance exercises are highly recommended to reduce this problem and to improve health, well-being, and independence in old age. However, many older people face a lack of motivation in addition to other strong barriers to exercise. We developed ActiveLifestyle, an information technology (IT)-based system for active and healthy aging aiming at improving balance and strength. ActiveLifestyle is a training app that runs on a tablet and assists, monitors and motivates older people to follow personalized training plans autonomously at home. Objective: The objectives were to (1) investigate which IT-mediated motivation strategies increase adherence to physical exercise training plans in older people, (2) assess the impact of ActiveLifestyle on physical activity behavior change, and (3) demonstrate the effectiveness of the ActiveLifestyle training to improve gait speed. Methods: A total of 44 older adults followed personalized, 12-week strength and balance training plans. All participants performed the exercises autonomously at home. Questionnaires were used to assess the technological familiarity and stage of behavior change, as well as the effectiveness of the motivation instruments adopted by ActiveLifestyle. Adherence to the exercise plan was evaluated using performance data collected by the app and through information given by the participants during the study. Pretests and posttests were performed to evaluate gait speed of the participants before and after the study. Results: Participants were 75 years (SD 6), predominantly female (64%), held a trade or professional diploma (54%), and their past profession was in a sitting position (43%). Of the 44 participants who enrolled, 33 (75%) completed the study. The app proved to assist and motivate independently living and healthy older adults to autonomously perform strength-balance exercises (median 6 on a 7-point Likert scale). Social motivation strategies proved more effective than individual strategies to stimulate the participants to comply with the training plan, as well as to change their behavior permanently toward a more physically active lifestyle. The exercises were effective to improve preferred and fast gait speed. Conclusions: ActiveLifestyle assisted and motivated independently living and healthy older people to autonomously perform strength-balance exercises over 12 weeks and had low dropout rates. The social motivation strategies were more effective to stimulate the participants to comply with the training plan and remain on the intervention. The adoption of assistive technology devices for physical intervention tends to motivate and retain older people exercising for longer periods of time

PsycINFO classification: 2300; 2323

Abstract Most research on visual search in aiming at far targets assumes preprogrammed motor control implying that relevant visual information is detected prior to the final shooting or throwing movements. Eye movement data indirectly support this claim for stationary tasks. Using the basketball jump shot as experimental task we investigated whether in dynamic tasks in which the target can be seen until ball release, continuous, instead of preprogrammed, motor control is possible. We tested this with the temporal occlusion paradigm: 10 expert shooters took shots under four viewing conditions, namely, no vision, full vision, early vision (vision occluded during the final AE350 ms before ball release), and late vision (vision occluded until these final AE350 ms). Late-vision shooting appeared to be as good as shooting with full vision while early-vision performance was severely impaired. The results imply that the final shooting movements were controlled by continuous detection and use of visual information until ball release. The data further suggest that visual and movement control of aiming at a far target develop in close correspondence with the style of execution. Ó 2002 Elsevier Science B.V. All rights reserved

Perception of limb orientation in the vertical plane depends on center of mass rather than inertial eigenvectors

We performed two experiments to test the hypothesis that the perception of limb orientation depends on inertial eigenvectors (

Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements

The influence of gaze behaviour on postural control from early childhood into adulthood.

In the present study we aimed to track the influence of natural gaze behaviour on postural control from early childhood into adulthood. We measured time series of centre of pressure (COP) as well as head movement in three children groups aged around five (n = 16), eight (n = 15), and eleven (n = 14) and in one group of young adults (n = 15) during quiet stance with eyes closed, gaze fixed on a dot, and with gaze shifts between two dots. We adopted magnitude and irregularity of COP displacement as indexes of postural control and cross correlation between COP displacement and target oscillation as an index of the dynamical coupling between the postural and visual systems. Magnitude and irregularity of COP displacement decreased with age, which suggests a steady improvement of postural control from five to beyond eleven years of age. Cross correlations were weak and relative phases highly variable across age groups. Across conditions, and most prominently in the gaze shift conditions, 5-year-olds showed both more head movement and lower postural stability than other age groups. Finally, only in 5-year-olds did we find a marked deterioration of postural stability with gaze shifts. We thus conclude that excessive head movement, particularly during gaze shifts, may be a primary cause of lower postural stability in young children compared to older children and adults

Kinematic Analysis of the Coupling Between Calcaneal Eversion and Ankle Dorsiflexion in a Contemporary Dancer’s Demi-Plié

BACKGROUND: Dancing requires a high range of motion in the foot as well as a good shock-absorbing system formed by the foot and ankle joints. Although there is a broad consensus in dance that excessive calcaneal eversion can cause injury and should be avoided, calcaneal eversion is discussed controversially in the dance literature. An increased research focus on the biomechanics of dance, particularly research pertaining to the foot and ankle joints, might help to resolve this controversy. OBJECTIVES: The study’s main purpose was to generate hitherto lacking kinematic data of calcaneal eversion in a dancer’s demi-plié. METHODS: Thirty-two contemporary dancers performed three trials in two different conditions: demi-plié in parallel and in turned-out positions. The motion capture system FASTRAK was used to measure calcaneal eversion and foot and lower leg alignment during demi-plié. RESULTS: Maximal calcaneal eversion in turned-out demi-pliés was 3.36°±4° and total range of motion (i.e., maximal minus minimal angle) of calcaneal eversion was 3.73°±1.42°, where the large standard deviations indicate substantial variability across participants. Calcaneal eversion was significantly different between turned-out (3.36°±4°) and parallel (1.17°±4.06°) demi-pliés, as was the alignment of the lower leg and foot, where the lower leg tracked more medially relative to the foot during turned-out pliés. Crucially, both the magnitude of calcaneal eversion and its temporal coupling with ankle dorsiflexion were highly variable across participants. CONCLUSIONS: Average calcaneal eversion is a poor indicator of the role calcaneal eversion plays in the demi-plié of contemporary dancers. Rather, the temporal coupling between calcaneal eversion and ankle dorsiflexion needs to be considered

Design considerations for a theory-driven exergame-based rehabilitation program to improve walking of persons with stroke

Virtual rehabilitation approaches for promoting motor recovery has attracted considerable attention in recent years. It appears to be a useful tool to provide beneficial and motivational rehabilitation conditions. Following a stroke, hemiparesis is one of the most disabling impairments and, therefore, many affected people often show substantial deficits in walking abilities. Hence, one of the major goals of stroke rehabilitation is to improve patients' gait characteristics and hence to regain their highest possible level of walking ability. Because previous studies indicate a relationship between walking and balance ability, this article proposes a stroke rehabilitation program that targets balance impairments to improve walking in stroke survivors. Most currently, available stroke rehabilitation programs lack a theory-driven, feasible template consistent with widely accepted motor learning principles and theories in rehabilitation. To address this hiatus, we explore the potential of a set of virtual reality games specifically developed for stroke rehabilitation and ordered according to an established two-dimensional motor skill classification taxonomy. We argue that the ensuing “exergame”-based rehabilitation program warrants individually tailored balance progression in a learning environment that allows variable practice and hence optimizes the recovery of walking ability.ISSN:1813-7253ISSN:1861-690

Postural control and head stability during natural gaze behaviour in 6- to 12- year-old children

We investigated how the influence of natural exploratory gaze behaviour on postural control develops from childhood into adulthood. In a cross-sectional design, we compared four age groups: 6-, 9-, 12-year-olds and young adults. Two experimental trials were performed: quiet stance with a fixed gaze (fixed) and quiet stance with natural exploratory gaze behaviour (exploratory). The latter was elicited by having participants watch an animated short film on a large screen in front of them. 3D head rotations in space and centre of pressure (COP) excursions on the ground plane were measured. Across conditions, both head rotation and COP displacement decreased with increasing age. Head movement was greater in the exploratory condition in all age groups. In all children—but not in adults—COP displacement was markedly greater in the exploratory condition. Bivariate correlations across groups showed highly significant positive correlations between COP displacement in ML direction and head rotation in yaw, roll, and pitch in both conditions. The regularity of COP displacements did not show a clear developmental trend, which indicates that COP dynamics were qualitatively similar across age groups. Together, the results suggest that the contribution of head movement to eye-head saccades decreases with age and that head instability—in part resulting from such gaze-related head movements—is an important limiting factor in children’s postural control. The lack of head stabilisation might particularly affect children in everyday activities in which both postural control and visual exploration are required