Les caractéristiques électrocardiographiques et échocardiographiques du rugbyman

Aim. – To describe the electrocardiographic and echocardiographic patterns of a group of high level trained French rugbymen.Patients and methods. – Thirty-five French first league’s rugbymen were studied with a resting electrocardiogram and left ventricular echocardiography. They performed two field tests to assess their maximal anaerobic power (MAP) and their maximal aerobic velocity (MAV).Results. – Resting electrocardiogram showed neither significant arrhythmia nor atrioventricular or intraventricular delay. A high prevalence of lateral early repolarisation was notified. Echocardiography found moderately dilated left ventricles with no significant increase of parietal thickness or left ventricular mass index. Resting systolic as diastolic function was unaltered. Cardiac patterns and field tests parameters were not significantly correlated. However, we noted a trend between P wave size and MAP as well as maximal heart rate; and between left ventricular end-diastolic diameter and MAV.Conclusion. – This study suggests that the high level of isometric and dynamic physical training sustained by French first league’s rugbymen do not induce major alterations of their electrocardiogram or of their left ventricle echocardiographic patterns.     

L'enfant diabétique à l'exercice : étude multiparamétrique

Methods and results – A multiparametric study was realised on insulinodependant diabetic children (n=11) and on control children (n=24) during linear incremental test on ergocycle, normalised with respect to their own maximal aerobic power. It consist in quantifying electromyographic signal of quadriceps muscle (total energy and mean power frequency of the signal), and cardiorespiratory variables (maximal oxygen consumption, heart rate) and metabolic variables (glycemia, lactatemia). Results showed no significant difference of cardiorespiratory changes and significant difference with metabolic changes between diabetic or control children. Changes in electromyographic variables exhibit different profiles between children but not between groups. A discriminant analysis realised on the set of mean power frequency profiles showed difference between diabetic or control children.Conclusion – Thus, electromyographic changes allowed to characterise exercise aptitude for diabetic children.     

Estimation de la dépense énergétique lors d'une régate en dériveur

Introduction. – Assess the energetic cost during small craft competition.Methods. – Height healthy sailors have been tested during three regattas. Heart rate, vertical jump, glycemia, cortisol and testosterone have been recorded.Results and discussion. – Regattas did not show significant difference for hormones. However, a significant 10% decrease of glycemia was presented. Heart rate increased during competition, but it was different according to the wind velocity and wind direction. The oxygen cost of sailing is relatively light. However, this cost could be increase with bad conditions of sailing. It seems that aerobic capacity is important regarding performance.     

Facteurs mécaniques du coût énergétique dans trois locomotions humaines

Objectives – The aim of this review is to detail the mechanical factors of the energy cost in three human locomotions, which are swimming, cycling and running.Topics – The hydro- or aero-dynamic drags (i.e., pressure and friction drags) are the most important external resistances, encountered by the locomotion in swimming and cycling. The influence of the gradient of the slope, the body mass, the additional weights, the velocity, the cycle frequency and length, the mechanical power and the stretch-shortening-cycle on the energy cost is also reported.Future prospects – The measure of the gas exchanges in situ during the training sessions with portable devices could be linked to the quantification of the mechanical energy and would make possible the evaluation of the muscular efficiency of athletes in their real activity and allowing also an objective measurement of their technical ability in the locomotion.     

Peut-on encore améliorer la méthodologie des épreuves d’effort maximales pour un suivi longitudinal plus informatif de la filière énergétique aérobie ?

Introduction  – The aim of this work was in a first time to propose the validation of the concept of fractional uses of reserves (Fu r) and especially, in a second time to test the pertinence of this concept in the appreciation of the possible effects of training on aerobic endurance.Synthesis of facts – The first set regrouped 89 athletic males (49 endurance sportsmen and 40 team sportsmen) with aerobic endurance clearly different. The second set reassembled 27 sportsmen of all disciplines in the course of a period of endurance training.Conclusion – The Fu r of the three magnitudes (HR–W–VO₂) selected provides effectively submaximal indices of aerobic endurance. Fu r to VT₁ and to R = 1,00 appear as excellent indicators of aerobic endurance, particularly for VT₁, the Fu r follow the long-term evolution of aerobic endurance on several years. Fu r to R = 1,00 (HR–W–VO₂) and to VT₂ (HR and W but not for VO₂) appear, for a sportsman’s longitudinal follow up, as indicators of variation of the aerobic endurance in response to training during the course of a sports season.