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Summary Objectives To evaluate the effect of dorsiflexion shoes on the energy cost of running (Cr), with or without noticeable acute neuromuscular fatigue. Methods On four separate occasions, thirteen trained subjects (23.1 ± 4.2 y), wearing standard (twice) or dorsiflexion (twice) shoes, performed two successive 5-min submaximal running exercise bouts (Sub 1 and Sub 2 , 45% of the speed reached at the end of the 30–15 Intermittent Fitness Test), interspersed by a repeated sprint exercise aimed at inducing acute neuromuscular fatigue. Oxygen uptake ( V ˙ O 2 ), heart rate (HR), blood lactate (Δ[La] b ) and rating of perceived exertion (RPE) were computed for all tests. Cr was calculated using the mean V ˙ O 2 measured over the last three minutes of Sub 1 and Sub 2 , and expressed in ml kg −1 m −1 . Results HR, Δ[La] b and RPE were significantly higher for Sub 2 ( P b were lower for dorsiflexion compared with standard shoes ( P = 0.03), without a ‘shoe x repetition’ interaction for any parameter ( P > 0.46). Nevertheless, for Sub 2 , qualitative analyses suggested that HR, V ˙ O 2 and Cr tended to be higher, and Δ[La] b tended to be lower wearing dorsiflexion (i.e., ‘very likely’ (99%) substantial effect on Cr). Conclusions Present results suggest that wearing dorsiflexion shoes may reduce blood lactate levels but increase Cr under conditions of acute neuromuscular fatigue.

Resume Introduction Le 30-15 Intermittent Fitness Tests (30-15IFT) permet d’atteindre une vitesse maximale (VIFT) tres bien correlee avec la plupart des qualites determinantes en sport collectif : vitesse, explosivite, puissance maximale aerobie et recuperation cardiorespiratoire inter-efforts. Cependant, la relation entre VIFT et capacite de repetition de sprints n’avait pas encore ete evaluee. Synthese des faits Les resultats montrent que, chez 84 athletes, la VIFT est negativement correlee au temps moyen du test de repetition de sprints (p > 0,001). Conclusion Fortement correlee aux principaux determinants physiques de la performance en sport collectif, la VIFT peut ainsi etre utilisee pour evaluer de maniere globale le potentiel athletique des joueurs.

Resume Introduction Pour suivre le niveau de performance athletique d’une equipe de sport collectif au cours d’une saison, utiliser une batterie complete de tests est chronophage. L’ideal serait de ne proposer qu’un seul test de suivi regulier. Synthese des faits Nous avons tente de determiner lequel etait le plus sensible aux variations de performance au fil de la saison. Conclusion Il s’avere que les resultats obtenus au 30-15 Intermittent Fitness Test et a un test de repetition de sprint, a l’inverse de ceux obtenus aux tests de vitesse ou de detente, permettent de differencier le niveau global de performance athletique lors des differentes periodes de la saison.

The concept description formalisms of existing description logics systems allow the user to express local cardinality restrictions on the fillers of a particular role. It is not possible, however, to introduce global restrictions on the number of instances of a given concept. This article argues that such cardinality restrictions on concepts are of importance in applications such as configuration of technical systems, an application domain of description logics systems that is currently gaining in interest. It shows that including such restrictions in the description language leaves the important inference problems such as instance testing decidable. The algorithm combines and simplifies the ideas developed for the treatment of qualified number restrictions and of general terminological axioms.

Subsumption between queries is a valuable information, e.g., for semantic query optimization. We approach the subsumption problem in the setting of object-oriented databases, and find that reasoning techniques from Artificial Intelligence can be applied and yield efficient algorithms.