Variabilité de la fréquence cardiaque en fonction de l'intensité de la pratique physique chez la femme ménopausée

Aim. – Study was to asses the heart rate variability related to the physical practice intensity in post menopausal women.Method. – Time domain measurement of heart rate variability has been realised from the electrocardiogram at rest and during exercice in 3 groups of 6 women : untrained, active and trained. At rest, no significant difference betwen groups appears. But, in the standing position, RR interval and the dispersion around RR interval decrease in trained group only. During submaximal exercise, this dispersion is more elevated in active and trained groups.Conclusion. – Physical practice induces a higher response of sinus node to vagal modulation during standing position and submaximal exercise.     

Réponses du cortisol et de la testostérone salivaires au cours de la récupération post-compétitive en rugby

Aim. – In order to evaluate the biological repercussions of the post-competitive tiredness state, we measured the progress of the salivary cortisol and testosterone levels in the players of a rugby-team during the week following an international match.Results. – The results reveal a fall of the cortisol levels during the first 4 days following the competition, compared to the values measured at the same hour of a resting day. Conversely, the testosterone levels present an increase during the same period. Consequently, 5 days of recovery are needed for these two biological variables chosen as tiredness markers to return to their basic values.     

Protéines et acides aminés dans la récupération post-effort

Recent data. – Recent evidence suggests an interest for the intake of nitrogenous substances during the anabolic post-exercise phase. Modest amounts of indispensable amino acids stimulate net protein gain and might contribute to long term training adaptations in muscle. Proteins play a subsidiary but limited role in glycogen resynthesis. Regarding other functions theoretically susceptible to be modulated by specific amino acids, for instance cysteine and glutamine, no quantitative evidence exists today demonstrating that amino acid-specific supplements would benefit healthy athletes.     

Médicaments et performance de la fonction d'équilibration

Introduction – Balance control in some sports discipline can be the aim of the action, and its breaking off can expose to severe trauma.Synthesis of facts – Some drugs' adverse effects can induce lower equilibrium performance, in relation for example with vigilance drop or vestibular ototoxicity. The drug effect site can concern one or more links in the chain (peripheral or central impact). Individual sensitivity is variable, as well as speed of reversibility.Conclusion – Symptoms induced by pathology for which therapy is prescribed are sometimes difficult to distinguish from those induced by therapy itself.     

Dynamique de la locomotion en fauteuil roulant manuel : influences de la masse totale et de sa répartition antéropostérieure sur la résultante des forces de freinage

Purpose. – This study presents a new method for determining the resultant braking force during wheelchair displacement and investigates the respective effects of the level and the distribution of the system’s mass.Method and results. – A three-dimensional accelerometer was fixed directly under the seat of wheelchair and was used to measure the deceleration of the mass-and-wheelchair’s system. Three masses (50, 70 and 90 kg) were laid on a support in 3 positions corresponding to three distributions (10, 40 and 70%) of the system’s total mass upon the front casters. A series of 15 deceleration trials was performed for each of the 9 combinations. Statistical results showed that the system’s deceleration was mainly explained by the mass distribution upon the front casters (92%) and in the least by the system’s total mass (8%).Conclusion. – Considering the fore-and-aft movements of the subject’s centre of mass during wheelchair locomotion, the results of this study let us assume that the resultant braking force does not remain constant along the propulsion cycle. Moreover, the present method could be used to investigate the influence of wheelchair’s adjustments and floor’s characteristics on the resultant braking force.     

Imagerie de la trachée de l'adulte

Imaging of normal and pathologic trachea at the thoracic and cervical levels is described extensively. Beside congenital abnormalities discovered in adulthood, acquired tracheal abnormalities are artificially divided in two subgroups. One group consists of diffuse abnormalities, with all but one diseases associated with a diffuse narrowing of the tracheal lumen. The other group comprises focal abnormalities that lead to tracheal stenoses of various lengths, with a postintubation stenosis as probably the most frequent cause, followed by tumours. The main modality for tracheal imaging is now multidetector-row spiral CT. This technique allows for faster volume coverage and higher spatial and temporal resolution. The improved spatial resolution impacts on both axial images and all reconstructions techniques that have become indispensable for interpretation of a vertical structure such as the trachea. Chest X-ray is no longer the frontline imaging technique. MRI has not yet reached all its potential as compared to CT.     

Approche biomécanique du cyclisme moderne,données de la littérature

Aims – To carry out a review of the literature in connection with optimisation of the body position in cycling.Current knowledge – Well-studied subject in the field of biomechanics of sport, it seems important in to draw up a bibliographic assessment in order to realise a physiological, ergonomic and mechanical interpretation of body position in cycling. This interpretation will be mainly based on a pedalling analysis, a definition of postural references which can influence energetic cost in cycling and the choice of parameters which allow repeatable measurements or which are easily found.Points of views and plans – This article opens the prospect for research dealing with multivariable and multidisciplinary postural optimization.