Inspiratory muscle fatigue in swimmers after a single 200 m swim

Inspiratory muscle fatigue may occur in as little as 6 min during high-intensity spontaneously breathing exercise. The aims of this study were to determine whether inspiratory muscle fatigue occurs during swimming exercise and whether inspiratory muscle strength differs between the supine and standing body positions. Seven competitive swimmers were recruited to perform a single 200 m front-crawl swim, corresponding to 90-95% of race pace. Inspiratory muscle strength was measured at residual volume using a hand-held mouth pressure meter that measured maximal inspiratory pressure in the upright and supine positions. At baseline, maximal inspiratory pressure in the supine position was significantly lower than maximal inspiratory pressure in the upright position (112±20.4 and 133±16.7 cmH₂O, respectively; P?0.01). Post-exercise maximal inspiratory pressure in the supine position (80±15.7 cmH₂O) was significantly lower than baseline maximal inspiratory pressure in the supine position (P?0.01). The results indicate that a single 200 m front-crawl swim corresponding to 90-95% of race pace was sufficient to induce inspiratory muscle fatigue in less than 2.7 min. Furthermore, although diaphragm muscle length is optimized when supine, our results indicate that the force output of the diaphragm and inspiratory accessory muscles is greater when upright than when supine.     

What Do Dragons Think About in their Dark Lonely Caves? [1] or Critical Studies: The Importance of Knowledge

Increasing numbers of Critical Studies publications are currently reaching the market, with teachers receiving numerous advertising materials and catalogues to persuade them to buy. This paper considers the content and approach of some of these materials, with particular reference to the teaching packs, and examines some of the issues that the decisions embodied in these publications raise for art teachers and for Critical Studies teaching. The orthodoxies that would seem to be developing are worrying, and rigorous debate is needed to expose and explore the grounds on which categories of inclusion and exclusion are constructed. It is argued that such debate needs to be underpinned by knowledge of the paradigms in operation, and that access to such knowledge is essential, for both teachers and students, if Critical Studies is not to degenerate into imaginative speculation or indoctrination.     

The demand for and use of outcomes information

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Teaching Post-structuralist Feminist Theory in Education: Student resistances

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