Introduction: There is an increasing endeavor to use Virtual Reality (VR) technologies in sports training. Because visual perception is crucial for sports performance, it should also be considered in the development of VR tools. The aim of this review is to summarise the literature on the application fields and domains of sport in VR and to examine what needs to be considered when developing such VR training tools with regard to visual perception and its manipulation. Furthermore, it is still unclear to what extent the user's body or that of their teammates or opponents must be visualized in VR.Methods: The literature search was conducted based on five databases: PsychInfo, Pubmed, Scopus, SportDiscus, and IEEE Explore. Review articles and original articles written in English and published between 1 January 2015 and 31 March 2024 were considered.Results: Through a qualitative analysis of the selected research, we identified 12 reviews and 46 research articles. While the applications of VR in sports initially focussed on endurance sports at the beginning of the development of VR tools, within the last 5 years VR was found in almost all sports, such as team sports, martial arts, and individual sports. The most common sports domains in which VR is used are motor learning, training of visual perception, decision making processes, and anticipation skills, as well as many sport-specific trainings. The review provides an overview of the extent to which visual aids in VR can be used to optimize motor learning and training, also taking into account the transfer to the real world.Discussion: VR offers many opportunities to visually support sports training and motor learning. It has been shown that training in VR based purely on visual perception can be successful in many sports and sports domains. The following visualization options are already being used: different viewing perspectives, variation of the demonstrated speed of movement, use of virtual mirrors, visualization of the necessary body parts, visual manipulation to identify important stimuli, display of movement trajectories, and graphic aids. In future, more studies should be conducted to compare training under virtual conditions with training under real conditions and to investigate transfer effects. Eye tracking should also be used for this purpose in order to compare visual perception in VR and in reality. Less is known about how VR training can be realized in terms of frequency, duration, and intensity and how VR training can be combined with training in the reality world.

Recent studies demonstrate a slowdown in deterioration of cognitive functioning in old age through aerobic training. There is evidence that the combination of aerobic, balance, and coordination exercises leads to an improvement or maintenance of cognitive functions. Such age-related exercises can especially be found in East Asian martial arts. The purpose of the current study is to verify whether karate training for older adults improves cognitive functioning and, if an improvement can be found, which cognitive fields are influenced. Eighty-nine older women and men (mean age: 70 years) participated in this study. The participants were randomized into 2 intervention groups (karate group and fitness group, duration of intervention: 5 months) and a control group. All participants had to accomplish a cognitive test battery before and after the intervention. In a secondary study the karate group had an additional intervention for another 5 months. The results show that there is a significant improvement in motor reactivity, stress tolerance, and divided attention only after the 5-month karate training period. Additionally, the results of the secondary study indicate further improvements after 10 months. The 5-month karate training can help to enhance attention, resilience, and motor reaction time, but a training period of 10 months is even more efficient.

Because of the complexity of sports movements, biomechanical analyses contain many kinematical or dynamical parameters and characteristic curves. Principal component analysis (PCA) is a technique for simplifying a dataset by reducing multidimensional datasets to lower dimensions for analysis. The purpose of this article is the presentation of several studies which used the PCA to solve various problems in the movement science in sports. In particular, we interpret the number of the components or also named components with relatively high eigenvalues as the number of degrees of freedom. For cyclic and automated movements, the first PCA component is dominant. The PCA was successfully applied to gait analyses in rehabilitation and in triathlon as well as in riding. Phase plots could be used to quantify the variability of the movement coordination.

Virtual reality (VR) training has become valuable in sports to improve motor behavior and train specific situations under standardized conditions. However, studies comparing conventional training with VR training are rare, especially for advanced athletes. Furthermore, it remains unclear whether the performance improvement achieved through VR training can be transferred to the real world (RW). Therefore, we present a study analyzing sports-specific response training using a head-mounted display (HMD) combined with conventional training and its transfer to RW. In ten training sessions over 6 weeks, a VR training group (VRG, n = 15) performed virtual karate training (10 min) combined with a conventional training (80 min), while a conventional training group (CG, n = 12) conducted only conventional training (90 min) at the same time. The VR training consisted of the athlete responding to various karate attacks performed by a virtual opponent in a karate-specific manner. The study design included a pretest, an intermediate test (after 5 training sessions), and a posttest. We analyzed sports-specific response behavior concerning the competition-relevant karate attacks Gyaku-Zuki jodan (GZj) and Kizami-Zuki (KZ) using the parameters ‘response time’, and the “response quality” when the athletes had to react to attacks of a virtual opponent in VR and a real opponent in RW. For the parameter “response time,” improvements were detected only for the VRG in VR concerning GZj and KZ. For the parameter “response quality” for both groups, no improvements could be found. Furthermore, athletes provided positive feedback regarding the integration of VR training into conventional training.

For realistic and reliable full-body visualization in virtual reality, the HTC VIVE Tracker could be an alternative to highly complex and cost- and effort-intensive motion capture systems such as Vicon. Due to its lighter weight and smaller dimensions, the latest generation of trackers is proving to be very promising for capturing human movements. The aim of this study was to investigate the accuracy of the HTC VIVE Tracker 3.0 compared to the gold-standard Vicon for different arrangements of the base stations and various velocities during an athletic movement. Therefore, the position data from three trackers attached to the hip, knee and ankle of one sporty participant were recorded while riding a bicycle ergometer at different pedaling frequencies and different base station arrangements. As parameters for the measurement accuracy, the trajectories of the linear motion of the knee and the circular motion of the ankle were compared between VIVE and Vicon by calculating the spatial distance from the raw data at each point in time. Both the pedaling frequency and the arrangement of the base stations significantly affected the measurement accuracy, with the lowest pedaling frequency of 80 rpm and the rectangular arrangement recommended by the manufacturer showing the smallest spatial differences of 10.4 mm ± 4.5 mm at the knee and 11.3 mm ± 5.1 mm at the ankle. As the pedaling frequency increased gradually (120 rpm and 160 rpm), the measurement accuracy of the trackers per step decreased less at the knee (approximately 5 mm) than at the ankle (approximately 10 mm). In conclusion, the measurement accuracy for various athletic skills was high enough to enable the visualization of body limbs or the entire body using inverse kinematics in VR on the one hand and, on the other hand, to provide initial insights into the quality of certain techniques at lower speeds in sports science research. However, the VIVE trackers are not suitable for exact biomechanical analyses.