Endurance and strength training effects on physiological and muscular parameters during prolonged cycling

International audiencePurpose: This study investigated the effects of a combined endurance and strength training on the physiological and neuromuscular parameters during a 2-hour cycling test.Methods: Fourteen triathletes were assigned to an endurance-strength training group (ES) and an endurance-only training group (E). They performed 3 experimental trials before and after training: an incremental cycling test to exhaustion, a maximal concentric lower-limbs strength measurement and a 2-hour cycling exercise. Physiological parameters, free cycling chosen cadence (FCC) and the EMG of Vastus Lateralis (VL) and Rectus Femoris (RF) were analysed during the 2-hour cycling task.Results: The results showed that the maximum strength and the isometric maximal voluntary contraction (isoMVC) after training were significantly higher (P<0.01) and lower (P<0.01) than before training, respectively in ES and E groups. The physiological variables measured during the cycling tests and the progressive increase (P<0.01) in EMGi (VL) and EMGi (RF) throughout the 2-hour cycling test did not differ between the two groups before and after training, except for the variation of EMGi (VL) over the cycle time which was stabilized during the second hour of the 2-hour cycling test due to training in ES group. The decrease in FCC observed in pre-training (P<0.01) was also replaced by a steady FCC for the ES-group during the second hour of exercise.Conclusion: This study confirmed the decrease in the FCC with exercise duration and demonstrated that a specific combined endurance and strength training can prevent this decrease during a 2-hour constant cycling exercise

Influence de l'expertise sur l'évolution de la cadence de pédalage au cours d'un test progressif maximal

International audienceAim. – The purpose of this work is the study of the evolution of the freely chosen cadence (FCC) during a pedalling test, applied to various populations with different physical and physiological capacities. Materials and methods. – Three groups of 8 subjects (less-trained non-cyclists, OCC – trained cyclists, CYC – trained runners, COU) participated in this experimentation. During a same session of evaluation, each subject realized a test of determination of the maximal dynamic strength of the lower limbs. This test was followed 1 hour later by a progressive, maximal and continuous test for determination of maximal oxygen uptake (_V O2max) on an electromagnetic brake-cycle ergometer. Results. – Our results show that trained cyclists adopt a constant FCC, while non-cyclists (i.e. OCC and COU) significantly increase their FCC between the beginning and the end of the test. Besides, although the FCC of the cyclists is significantly higher than the FCC of the noncyclists at the beginning of the exercise, one does not see any persisting difference between the FCC of the three populations, later on. Conclusion. – The stability of cyclists’ FCC can be explained through expertise, that is, throw the fact that the subjects develop specific skills inferred by a learning process.Objectifs. – L'objectif de ce travail est d'étudier la cadence librement choisie (CLC) au cours d'une épreuve de pédalage dite « triangulaire » chez différentes populations de sujets disposant d'aptitudes physiques et physiologiques différentes. Méthodes. – Trois groupes de huit sujets (sportifs occasionnels, OCC – cyclistes régionaux, nationaux, CYC – coureurs régionaux, COU) ont participé à cette expérimentation. Il leur a été demandé de réaliser, lors d'une même session d'évaluation, un test de détermination de force maximale dynamique des membres inférieurs suivi, une heure plus tard, d'un test progressif, maximal, continu de détermination de la consom-mation maximale d'oxygène (_ VO 2max) sur ergocycle à frein électromagnétique. Résultats. – Nos résultats mettent en évidence l'adoption d'une CLC constante chez les cyclistes alors que les non cyclistes (i.e. OCC et COU) augmentent significativement leur CLC entre le début et la fin du test. En outre, bien que la CLC des cyclistes soit significativement plus élevée que celle des non cyclistes en début d'exercice, il n'existe ensuite plus aucune différence significative entre la CLC des trois populations. Conclusion. – La stabilité de CLC des cyclistes peut être expliquée par l'expertise, c'est-à-dire, par le développement d'habiletés spécifiques induites par un processus d'apprentissage

Endurance and strength training effects on physiological and muscular parameters during prolonged cycling

International audiencePurpose: This study investigated the effects of a combined endurance and strength training on the physiological and neuromuscular parameters during a 2-hour cycling test.Methods: Fourteen triathletes were assigned to an endurance-strength training group (ES) and an endurance-only training group (E). They performed 3 experimental trials before and after training: an incremental cycling test to exhaustion, a maximal concentric lower-limbs strength measurement and a 2-hour cycling exercise. Physiological parameters, free cycling chosen cadence (FCC) and the EMG of Vastus Lateralis (VL) and Rectus Femoris (RF) were analysed during the 2-hour cycling task.Results: The results showed that the maximum strength and the isometric maximal voluntary contraction (isoMVC) after training were significantly higher (P<0.01) and lower (P<0.01) than before training, respectively in ES and E groups. The physiological variables measured during the cycling tests and the progressive increase (P<0.01) in EMGi (VL) and EMGi (RF) throughout the 2-hour cycling test did not differ between the two groups before and after training, except for the variation of EMGi (VL) over the cycle time which was stabilized during the second hour of the 2-hour cycling test due to training in ES group. The decrease in FCC observed in pre-training (P<0.01) was also replaced by a steady FCC for the ES-group during the second hour of exercise.Conclusion: This study confirmed the decrease in the FCC with exercise duration and demonstrated that a specific combined endurance and strength training can prevent this decrease during a 2-hour constant cycling exercise