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The aim of the study was to assess the impact of proprioceptive training with the use of virtual reality (VR) on the level of postural stability of high–altitude workers. Twenty-one men working at height were randomly assigned to the experimental group (EG) with training (n = 10) and control group (CG) without training (n = 11). Path length of the displacement of the center of pressure (COP) signal and its components in the anteroposterior and medial–lateral directions were measured with use of an AccuGaitTM force plate before and after intervention (6 weeks, 2 sessions × 30 min a week). Tests were performed at two different platform heights, with or without eyes open and with or without a dual task. Two–way ANOVA revealed statistically significant interaction effects for low–high threat, eyes open-eyes closed, and single task-dual task. Post-training values of average COP length were significantly lower in the EG than before training for all analyzed parameters. Based on these results, it can be concluded that the use of proprioceptive training with use of VR can support, or even replace, traditional methods of balance training.

Introduction and objective. Systematic monitoring of physical activity of young populations from different regions may be useful for making international comparisons, better understanding trends in physical activity and designing public health interventions to increase physical activity. Thus, the aim of the study was to comprehensively review studies examining the level of physical activity of children and adolescents from the Visegrád countries, and indicate the percentage of children and adolescents meeting the recommended level of physical activity. Materials and method. A systematic search of the published literature was conducted. Included were reports with original research that consisted of the proportion of children and adolescents who met physical activity recommendations or guidelines. To provide a current picture of physical activity of children and adolescents, the review was restricted to studies published between January 2015-November 2018. Results. Moderate-to-vigorous physical activity recommendations were met by between 7.5%-69.4% of children and adolescents. Vigorous physical activity recommendations were met by between 33.6%-64.5% of children and adolescents. Daily recommendations for the number of steps taken were fulfilled by between 11.6%-69.0% of children and adolescents. Differences between age categories, genders and countries were observed. Conclusions. Public health interventions to increase physical activity are required to decrease insufficient levels of physical activity in children and adolescents, especially in girls. The review also highlights the need for studies with representative random samples that use validated measurement methods.

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The smartphone has recently become a commonly used tool for satellite navigation. The reliability of built-in smartphone Global Navigation Satellite Systems receivers was analyzed in terms of distance, velocity/speed and acceleration, but little is known about the accuracy of angular change-of-direction measurements. This might be important in the assessment of usefulness in sailing navigation. The aim of the study was to assess the reliability of the calculated change-of-direction angles, measured with the built-in smartphone Global Navigation Satellite Systems technology using the SoniSailing application. One individual completed five trials in an urban open space (sports ground), wearing six identical Samsung Galaxy J5 smartphones. The trials simulated an upwind sailing race (127 m), including two consecutive courses at 45° angle to the line of the tacking leg. To assess the reliability of change-of-direction angle measures the intra- and inter-device correlation coefficients were calculated. The analysis showed excellent reliability in change-of-direction angle measures—no less than 0.95 and 0.93 in case of correlation coefficients for inter- and intra-device, respectively. Correlation coefficients for average measures were no less than 0.99 in both cases. The study confirmed high reliability of the calculated change-of-direction angles, measured with the Global Navigation Satellite Systems technology using the SoniSailing application for smartphones.

Thus far, the differences in effect of auditory or visual feedback in motor learning have presented results derived from mixed groups and sex differences have not been considered. However, perception and processing of auditory stimuli and performance of visual motor tasks appear to be sex-related. The purpose of this study was to investigate the learning of the simple motor task of maintaining a requested handgrip force in separate male and female groups. A total of 31 volunteers (15 males, 16 females) were randomly assigned to one of four experimental groups with defined sex and training conditions (audio or visual feedback). Participants performed training sessions over a period of six days, for which auditory or visual feedback was provided, and the effectiveness of both types of signals was compared. The evident learning effect was found in all groups, and the main effect of sex was significant among visual groups in favor of the males (p < 0.05). On the other hand, the main effect of feedback conditions was found to be significant among females, beneficially in the case of auditory displays (p < 0.05). The results lead to the conclusion that an equal number of males and females in mixed experimental groups may be supportive to obtain reliable results. Moreover, in motor-learning studies conducted on females only, a design including auditory feedback would be more suitable.

The open-water training conditions in sailing sports limit the coach’s ability to provide instructions. Auditory feedback provided using a smartphone application in real-time seems to be a promising tool in the training process. The aim of the study was to assess the usefulness of a smartphone application created to support tactical decisions via an auditory display. Thirteen successful windsurfers competing in RS:X class took part in the study. The results, collected with the use of a questionnaire, related to the technical and aesthetic aspects of the functions as well as decision-making assistance of the application during upwind sailing races. Most of the competitors positively evaluated application function (54–85%). Real-time information about the deviation from the set course and information about potential tack change due to a changed wind direction were statistically significantly more helpful for less experienced windsurfers (rho = −0.68 and rho = −0.78, respectively) and those with lower sports level (rho = −0.63 and rho = −0.65, respectively). It can be concluded that the use of sound feedback in the conditions of training on-water in sailing has potential, primarily for younger and less experienced competitors. Quantitative evaluations of the sailing performance should be considered in further research on the functionality of the application.

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