BackgroundNumerous daily activities require simultaneous application of motor and cognitive skills (dual-tasking). The execution of such tasks is especially difficult for the elderly and for people with (neuro-) degenerative disorders. Training of physical and cognitive abilities helps prevent or slow down the age-related decline of cognition. The aim of this review is to summarise and assess the role of combined physical-and-cognitive-training characteristics in improving cognitive performance and to propose an effective training scheme within the frame of a suitable experimental design.MethodsA systematic electronic literature search was conducted in selected databases. The following criteria were compulsory for inclusion in the study: 1. A (Randomized) Controlled Trial (RCT or CT) design; 2. Implementation of combined physical and cognitive training, either simultaneously (dual task) or subsequently - at least one hour per weekly over four weeks or more; 3. Cognitive outcomes as a study’s endpoint.ResultsTwenty articles met the inclusion criteria. It appears that either simultaneous or subsequently combined physical and cognitive training is more successful compared to single physical or single cognitive exercise. Training characteristics like length, frequency, duration, intensity and level of task difficulty seem to determine cognitive performance. However, the articles show that cognitive improvement seems to remain somewhat confined to trained cognitive functions rather than generalising to other cognitive or daily-living skills.ConclusionDue to methodological heterogeneity among studies, results need to be treated with caution. We critically discuss the role of training characteristics and propose a potentially effective training intervention within an appropriate experimental design.

BackgroundThe standardisation of the assessment methodology and case definition represents a major precondition for the comparison of study results and the conduction of meta-analyses. International guidelines provide recommendations for the standardisation of falls methodology; however, injurious falls have not been targeted. The aim of the present article was to review systematically the range of case definitions and methods used to measure and report on injurious falls in randomised controlled trials (RCTs) on fall prevention.MethodsAn electronic literature search of selected comprehensive databases was performed to identify injurious falls definitions in published trials. Inclusion criteria were: RCTs on falls prevention published in English, study population ≥ 65 years, definition of injurious falls as a study endpoint by using the terms "injuries" and "falls".ResultsThe search yielded 2089 articles, 2048 were excluded according to defined inclusion criteria. Forty-one articles were included. The systematic analysis of the methodology applied in RCTs disclosed substantial variations in the definition and methods used to measure and document injurious falls. The limited standardisation hampered comparability of study results. Our results also highlight that studies which used a similar, standardised definition of injurious falls showed comparable outcomes.ConclusionsNo standard for defining, measuring, and documenting injurious falls could be identified among published RCTs. A standardised injurious falls definition enhances the comparability of study results as demonstrated by a subgroup of RCTs used a similar definition. Recommendations for standardising the methodology are given in the present review.

Visual control has an influence on postural stability. Whilst vestibular, somatosensoric and cerebellar changes have already been frequency analytically parameterized with posturography, sufficient data regarding the visual system are still missing. The aim of this study was to evaluate the influence of pathologic and simulated visual dysfunctions on the postural system by calculating the frequency analytic representation of the visual system throughout the frequency range F1 (0.03-0.1 Hz) of Fourier analysis. The study was divided into two parts. In the first part, visually handicapped subjects and subjects with normal vision were investigated with posturography regarding postural stability (stability effect, Fourier spectrum of postural sway, etc.) with open and closed eyes. The visually impaired and the normal group differed significantly in the frequency range F1 (p = 0.002). Significant differences of the postural stability between both groups were found only in the test position with open eyes (NO). The healthy group showed a significant loss of stability, whereas the impaired group showed an increased stability due to sufficient somatosensoric processes. Visually handicapped persons can compensate the visual information deficit through improved peripheral-vestibular and somatosensoric perception and cerebellar processing. In the second part, subjects with normal vision were examined under simulated visual conditions, e.g., hyperopia (3.0 D), reduced visual acuity (VA = 20/200), yoke prisms (4 cm/m) and pursuits (pendulum). Changes in postural parameters due to simulations have been compared to a standard situation (open eyes [NO], fixation distance 3 m). Visual simulations showed influence on frequency range F1. Compared to the standard situation, significant differences have been found in reduced visual acuity, pursuits and yoke prisms. A loss of stability was measured for simulated hyperopia, pendulum and yoke prisms base down. Stability regulation can be understood as a multi-sensoric process by the visual, vestibular, somatosensoric and cerebellar system. Reduced influence of a single subsystem is compensated by the other subsystems. Obviously the main part of reduced visual input is compensated by the vestibular system. Moreover, the body sway, represented by the stability indicator, increased in this situation.

The aim of this investigation was to establish the validity of a GPS-based tracking system (Polar Team Pro System, PTPS) for estimating sprint performance and to evaluate additional diagnostic indices derived from the temporal course of the movement velocity. Thirty-four male soccer players (20 ± 4 years) performed a 20 m sprint test measured by timing gates (TG), and while wearing the PTPS. To evaluate the relevance of additional velocity-based parameters to discriminate between faster and slower athletes, the median-split method was applied to the 20-m times. Practical relevance was estimated using standardized mean differences (d) between the subgroups. Differences between the criterion reference (TG) and PTPS for the 10 and 20 m splits did not vary from zero (dt10: -0.01 ± 0.07 s, P = 0.7, d < -0.1; dt20: -0.01 ± 0.08 s, P = 0.4, d < -0.2). Although subgroups revealed large differences in their sprint times (d = -2.5), the average accelerations between 5 and 20 km/h as well as 20 and 25 km/h showed merely small effects (d < 0.5). Consequently, analyses of velocity curves derived from PTPS may help to clarify the occurrence of performance in outdoor sports. Thus, training consequences can be drawn which contribute to the differentiation and individualization of sprint training.

RehaWatch and the Interactive Balance System are able to measure two of the most important fall risk factors, but their current predictive ability is not satisfactory yet. The correlation with physiological mechanisms is only shown by the Interactive Balance System.