Influence of a proprioceptive training on functional ankle stability in young speed skaters – a prospective randomised study

The influence of a 12-week-proprioceptive training on functional ankle stability was investigated in young speed skaters. Twenty-eight speed skaters were randomly divided into an intervention (n = 14) and into a control group (n = 14). A 15-min circle training was performed 5 times per week over a 12-week period. Measurements were taken prior to the training, after 6 and 12 weeks of training. Kinaesthesia was evaluated with the Isomed2000 in all movements of the ankle joint. Dynamic balance was tested with the Biodex Stability System at the stable level 8 and at the unstable level 2, measuring the overall stability index, the anterior/posterior and the medial/lateral scores. Static single-leg stance was evaluated using the Kistler force platform. Kinaesthesia of the intervention group improved significantly for plantarflexion of the right foot (P = 0.001) after 12 weeks. Dynamic balance showed significant differences in the intervention group after 12 weeks in comparison with the first measurement for each foot in the overall stability index, the anterior/posterior and the medial/lateral scores (P ≤ 0.017, respectively) at the unstable level 2. Functional ankle stability improved in terms of dynamic balance after 12 weeks of proprioceptive training. Therefore, inclusion of proprioceptive exercises in the daily training programme is recommended for young speed skaters.     

Selbstkonzeptförderung im Sportunterricht

Previous intervention studies in school sports designed to test the socialisation hypothesis have tried to raise students’ self-concepts. However, this goal seems to be of questionable functionality: From both an educational and a psychological perspective, it would seem preferable to aim toward making self-concepts as realistic as possible. Underestimating self-concepts might impede performance-related behaviour, whereas overestimating might be dysfunctional, particularly in social interactions. This dichotomy is used to examine which manifestations of the self-concept physical education needs to promote from a psychological perspective. It creates a new perspective for future interventions designed to promote the self-concept in physical education.     

Outside directors on the board and innovative firm performance

We investigate how outside directors on supervisory boards influence innovative activities of the firms they advise and monitor. Based on panel data on the largest German companies, the econometric analysis shows a positive influence of external executives on innovative firm performance, measured by patent applications. Differentiating between outside directors from innovative and non-innovative companies reveals that only outside directors from innovative firms increase patenting activities at the firms they advise and monitor. This effect increases with the technological proximity between the appointing firm and the outsider's home firm. Outside directors from non-innovative firms are negatively associated with the appointing firm's innovativeness. The results indicate that external executives with an appropriate professional background can provide valuable specific knowledge and expertise to the board.