Background: Adults with sedentary lifestyles seem to face a higher risk of falling in their later years. Several causes, such as impairment of strength, coordination, and cognitive function, influence worsening health conditions, including balancing ability. Many modalities can be applied to improve the balance function and prevent falling. Several studies have also recorded the effects of balance training in elderly adults for fall prevention. Accordingly, the aim of this study is to define the effect of virtual reality-based balance training on motor learning and postural control abilities in healthy adults. Methods: For this study, ten subjects were randomly allocated into either the conventional exercise (CON) or the virtual reality (VR) group. The CON group underwent physical balance training, while the VR group used the virtual reality system 4 weeks. In the VR group, the scores from three game modes were utilized to describe the effect of motor learning and define the learning curves that were derived with the power law function. Wilcoxon Signed Ranks Test was performed to analyze the postural control in five standing tasks, and data were collected with the help of a force plate. Results: The average score was used to describe the effect of motor learning by deriving the mathematical models for determining the learning curve. Additionally, the models were classified into two exponential functions that relied on the aim and requirement skills. A negative exponential function was observed in the game mode, which requires the cognitive-motor function. In contrast, a positive exponential function was found in the game with use of only the motor skill. Moreover, this curve and its model were also used to describe the effect of learning in the long term and the ratio of difficulty in each game. In the balance performance, there was a significant decrease in the center of pressure parameters in the VR group, while in the CON group, there was a significant increase in the parameters during some foot placements, especially in the medio-lateral direction. Conclusion: The proposed VR-based training relies on the effect of motor learning in long-term training though different kinds of task training. In postural analysis, both exercise programs are emphasized to improve the balance ability in healthy adults. However, the virtual reality system can promote better outcomes to improve postural control post exercising. Trial registration Retrospectively registered on 25 April 2018. Trial number TCTR20180430005

Mental factors, such as arm length, sitting height, simple vision reaction time (SVRT), choice vision reaction time (CVRT), muscle strength, and range of motion (ROM) at the shoulder, elbow, and wrist joints to wheelchair basketball (WCB) performance as measured by season statistics and coaches’ evaluation. Methods: Thirty-seven Paralympic WCB players from seven countries participated in this study. A computerized reaction time system was used to test the SVRT and CVRT. The ROM and muscle strengths of the shoulder, elbow, and wrist joints were measured using a goniometer and MP DA100B BioPac force measurement system, respectively. Stepwise regression analysis was used to identify the contributions of these fundamental factors and “dimensional variables” (DV) derived from the selected factors fundamental to WCB performance. A DV represented a dimension or category of the factor, for example, the wrist flexion/extension DV represented the ROM of the wrist in flexion and extension, and the WCB performance DV represented average points, rebounds, assists, blocks, and steals per game. Results: The results of this study demonstrated that elbow extension and wrist extension had significant contributions to average points. Sitting height, shoulder internal rotation, and elbow flexion had significant contributions to the average rebounds. Arm length had a significant contribution to average assists, and SVRT had a significant contribution to the average blocks. Wrist flexion/extension ROM DV and wrist flexion/extension strength DV had significant contributions to the WCB performance DV. Conclusion: Shoulder internal rotation, elbow extension, and wrist flexion/extension ROM, CVRT, and wrist flexion/extension muscle strength are important to WCB performance and should be addressed in WCB training....

Excessive knee valgus during landing tasks is a contributing factor to knee injuries. Most studies have examined lower extremity biomechanics during the forward direction of a jump-landing task. Athletes perform many movements in the air and land in multi-directions. Therefore, the purpose of this study was to assess the peak knee valgus angle (PKVA) during one leg jump-landing in various directions.Eighteen male basketball and volleyball athletes participated in the study. Participants performed one leg jump-landing tests from a 30 cm height platform in four directions. Knee valgus motion was measured using Vicon motion system. The data were analyzed with repeated measures ANOVA.Direction significantly (P<0.001) influenced the PKVA during landing. Significantly higher PKVA was observed for the lateral (8.84.7) direction as compared to forward (5.84.6) direction (P<0.05). The PKVA in 30 diagonal (7.54.6) and 60 diagonal (7.75.7) directions was higher than in the forward direction (P<0.05).One leg jump-landing in lateral and diagonal directions results in a higher PKVA compared to landing in a forward direction and could lead to a higher risk of knee injury.

[Purpose] The purpose of this study was to assess the sagittal angles and moments of lower extremity joints during single-leg jump landing in various directions. [Subjects] Eighteen male athletes participated in the study. [Methods] Participants were asked to perform single-leg jump-landing tests in four directions. Angles and net joint moments of lower extremity joints in the sagittal plane were investigated during jump-landing tests from a 30-cm-high platform with a Vicon™ motion system. The data were analyzed with one-way repeated measures ANOVA. [Results] The results showed that knee joint flexion increased and hip joint flexion decreased at foot contact. In peak angle during landing, increasing ankle dorsiflexion and decreasing hip flexion were noted. In addition, an increase in ankle plantarflexor moment occurred. [Conclusion] Adjusting the dorsiflexion angle and plantarflexor moment during landing might be the dominant strategy of athletes responding to different directions of jump landing. Decreasing hip flexion during landing is associated with a stiff landing. Sport clinicians and athletes should focus on increasing knee and hip flexion angles, a soft landing technique, in diagonal and lateral directions to reduce risk of injury.