The rapid development and constant spread of miniaturized sensor technology and its applications (e.g. apps, inertial sensors, smartphones, etc.) is influencing (almost) all dimensions of our social and societal environments and increasingly also those of sport and healthcare (Thompson, 2019). As computers and interfaces are not only becoming more powerful in the calculation and processing of increasing amounts of data, but are also becoming smaller and smaller (Waldrop, 2016), they therefore represent an essential basis for self-learning automation processes. In the context of sport and healthcare, the fields of application are explicitly training monitoring, competition, regeneration management and (performance) or medical diagnostics (Düking et al., 2020). In addition to the long-standing use of miniaturized sensor technology for performance and movement analysis directly at the interface between humans and sports equipment (e.g. rowing boats, bicycles or bobsleds, etc.), wearable and/or body-worn sensors (wearables or wearable sensor technology) are increasingly being used (Düking, Achtzehn, Holmberg, & Sperlich, 2018; Düking, Holmberg, & Sperlich, 2017). Nowadays, athletes and active sportspeople mainly use wearables as smartwatches or fitness or activity trackers, for example to measure heart rate, energy consumption, training or physical exertion or stress analysis, to determine activity or inactivity status, to assess fitness status and for sleep and recovery monitoring (Seshadri et al., 2019). Wearables are also increasingly being used in the form of "smart" clothing such as T-shirts, socks or shoes, in the ear (hearables) or smart headphones or as "smart" patches. There are also sensors built into pills (ingestibles/implantables) that telemetrically transmit biosignals such as core body temperature or monitor medication intake. The relevance and importance of wearables is not only confirmed every year by their top ranking in the global fitness trends published by the American College of Sports Medicine - first place among fitness trends in 2020 with an estimated turnover of 95 billion dollars - (Thompson, 2018, 2019), but various international organizations such as the World Health Organization also speak out in favour of the potential added value of wearables for maintaining and/or improving certain aspects of health. In addition, more and more top associations are allowing the use of various wearables during competitions, for example to obtain feedback on various biosignals (including core body temperature, heart rate, fatigue index, etc.). Although the development and application of wearables in a sports and health-related context is still in its infancy, it is opening up interesting career opportunities for sports scientists due to increasing market figures and the acceptance of various organizations, sports associations and clubs (Sports Performance Analysis). Since commercially marketed wearables (which address the sports market) are currently not regulated in Germany and are not subject to independent verification of reliability and validity, experts will be needed in the future who can evaluate and assess the quality of the data provided (Kobsar et al., 2020). Companies are entering the sporting goods and health market with aggressive marketing messages, and many wearables do not deliver what they promise in practice (Sperlich & Holmberg, 2017). Parameters of commercially available wearables must therefore often be interpreted with extreme caution and a high degree of expert knowledge is required. The increasing number of available wearables and the growing number of measurable parameters leads to a flood of data, which affects, among other things, interpretability, data management, research ethics and data security (RatSWD [German Data Forum], 2020). Appropriately qualified and specially trained personnel are therefore needed who can assess the relevance of individual parameters, as well as interpret and evaluate them in the context of a particular sport and training or competition phase.

Literature

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