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.     

Évaluation de la fréquence cardiaque au cours d'exercices en apnée chez des plongeurs experts et débutants

Introduction – The aim of this study was designed to measure the evolution of the heart rate (FC) during pool repeated short breath hold at rest and at different underwater swimming velocities.Methods and results – The population was composed of ten male subjects subdivided into two groups: trained (expert) and beginners. Each subject had to perform one series of breath hold divings at rest and three series to different underwater swimming velocities. A series corresponded to six divings of 30 second duration separated by a recovery period of 30 second. Results pointed out, a bradycardia more important for the experts at rest and some tachycardia after the emersion less important for the experts.Conclusion – This difference between the two populations, measured during the series in breath hold with muscular efforts, was identical with the difference obtained during the measure of bradycardia at rest. For the trainer, the determination of a bradycardia in immersion during a breath hold at rest allowed evaluation of the training of the diver and to optimise the underwater swimming velocities according to avoid the breath hold breaking point.     

Fréquence cardiaque chez des adolescents âgés de 11 à 16 ans lors de séances d'éducation physique intensifiées

Introduction – Exercise physiologists notice sometimes that Physical Education (PE) sessions are lacking of intensity. This lack of intensity would not allow obtaining desired physiological responses. Thus, we measured heart rate (HR) in adolescents (boys and girls) aged 11–16 years old during intensified EP lessons.Method and results – Sessions consisted in short intermittent running (G1) and jumping exercises (G2). Heart rate was averaged over 30 min. There was no significant difference between mean HR for G1 and G2 (154±12 vs 155±12 bpm, p<0.001). Nevertheless, for both G1 and G2, mean HR was significantly higher for girls than for boys (153±12 vs 156±12 bpm, p<0.001).Conclusion – This type of intensified lessons request at a high level adolescents HR (75.4±5.4% of maximal HR) to reach health objectives.     

Évolution de la puissance maximale anaérobie au cours de la croissance chez le footballeur

Purpose – The aim of the study was to assess the improvement in Maximal Anaerobic Power (PMAna) from two tests in soccer players during growth.Methods – The experiment was carried out in 328 players, 11–18 years old, during their stay at the Clairefontaine National Soccer Center. PMAna was measured from the last 10 meters of the a 40 m-sprint test (ST) and a jump test (JT). The skeletal age (AO) is used as reference, and not the chronological one.Results – The results of the two tests are highly correlated (r= 0.8–0.9), PMAna values being always higher in the ST than in the JT.The most significant increase in PMAna occurs between 13 and 14 years AO (+47% for the ST, +27% for the JT), remains still significant up to 16 AO (respectively +38% and +24% between 14 and 16 AO), but the maximum value is reached at 17 AO. Between 12 and 16 AO, the PMAna value is multiplied by 2.29 for the ST and 1.81 for the JT.Conclusions – Sprint and jump tests seem well adapted to estimate PMAna in soccer players. The measure of the skeletal age during growth is needed for a better interpretation of the results. In addition, results obtained during growth allow a reliable estimation of PMAna in adulthood.