Institute of Sport Didactics and Physical Education, German Sport University, Cologne, Germany
Institute of Professional Sport Education and Sport Qualifications, German Sport University, Cologne, Germany
Institute of Outdoor Sports and Environmental Science, German Sport University, Cologne, Germany
Faculty of Sport Sciences, Waseda University, Shinjuku, Tokyo, Japan
Copyright © 2019 Daniel Klein, Tobias Vogt et al. This is
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