Ce projet se concentre sur la prise en charge non pharmacologique des patients atteints d'insuffisance cardiaque (HF), en mettant l'accent sur l'entraînement physique selon ses différentes modalités. Le but de cette étude est d'évaluer l'effet d'un programme combiné de deux ou trois modalités: entraînement aérobie en intervalles (AIT), entraînement musculaire inspiratoire (IMT) et entraînement contre résistance (RT) sur plusieurs paramètres tels que: la fonction des muscles cardiopulmonaire et squelettique, la dyspnée et la qualité de vie. En outre, cette thèse vise à chercher le meilleur type d'entraînement qui pourrait avoir des avantages supplémentaires sur les paramètres mesurés, fournissant ainsi une nouvelle application dans les programmes de réadaptation cardiaque. 60 patients atteints d'HF et de faiblesse musculaire inspiratoire (IMW) ont été répartis par randomisation dans l'un des groupes suivants: AIT (n = 10), IMT (n = 10), RT (n = 10), AIT + IMT (n = 10) et AIT + IMT + RT (n = 10). Les protocoles d'entraînements ont été effectués 3 fois par semaine pendant 12 semaines. Aucun changement n'a été détecté dans le groupe témoin. Tous les groupes ont montré des effets positifs significatifs sur presque tous les paramètres mesurés Cette thèse a permis de vérifier que la combinaison de l'AIT et de l'IMT a entraîné une amélioration supplémentaire des paramètres mesurés. Mais l'ajout de l'RT à l'AIT et à l'IMT a eu des avantages bénéfiques supplémentaires sur certains des paramètres mesurés par rapport au groupe combiné de deux modalités et à toutes les modalités d'entraînement, ce qui fait de la combinaison de deux modalités ou plus, le protocole le plus recommandé dans les programmes de réadaptation cardiaque / The present study shed lights on the non-pharmacological management in patients with heart failure (HF), with special focus on exercise training by its different modalities. The aim of this study is to evaluate the effect of a combined program of two or three modalities: aerobic interval training (AIT), inspiratory muscle training (IMT), and resistance training (RT), on several outcomes such as: cardiopulmonary and skeletal muscle function, dyspnea and quality of life (QoL). Moreover, this study aims to find the best training exercise that could have additional benefits on measured parameters, thus providing a novel application in cardiac rehabilitation programs. 60 patients with HF (New York Heart Association, NYHA≤45) and inspiratory muscle weakness (IMW) were randomly assigned to one of the six following groups (n=10, for each group): Control, AIT, IMT, RT, AIT+IMT and AIT+IMT+RT. The training regimens were performed 3 times per week for 12 weeks. No changes were detected in the control group. All groups showed significant positive effects on almost all the measured parameters. However, the combination of IMT to AIT and the addition of RT to IMT and AIT were the most powerful modalities and resulted in additional benefits over all training modalities. This study verified that, in patients with CHF and IMW, any exercise training, whether it is AIT, IMT or RT, improves the inspiratory muscle function, QoL, exercise performance and dyspnea. Moreover, the combination of the AIT and the IMT resulted in an additional improvement in the measured parameters. However, the addition of RT to AIT and IMT resulted in additional benefits in some of the measured parameters over the double combined group and all training modalities, which make the combination of two or more exercise training the most recommended protocol in cardiac rehabilitation programs

An increase in myofibrillar protein accretion can occur in the very early post-exercise period and can be potentiated by dietary protein intakes. The positive effect of nutrition on net muscle protein balance is credited to essential amino acids (EAAs), and particularly to the branched-chain amino acid leucine. Thus, leucine plays a key role in feeding-induced muscle protein synthesis by its unique ability to activate signalling pathways modulating translational initiation (Dreyer et al. 2008). Furthermore, strength exercise induces important disturbances in protein turnover, especially in novice athletes, and unaccustomed physical exercise, particularly repeated eccentric muscle contractions, induces muscle soreness and alterations in muscle cellular structure. Still, muscle strength gains induced by resistance training are mainly attributed to neural adaptations in the initial part of training, and subsequently to changes in the force capacity of muscle fibres due to hypertrophy (Duchateau et al. 2006; Sale, 1988). Since acute post-exercise muscle protein accretion does not inform on chronic muscle adaptations, the main purpose of this work is to test the effectiveness of an EAA supplementation on muscle hypertrophy and strength gains in response to resistance training, and on repair-oriented remodelling of disrupted muscle fibres in the early recovery period of an unaccustomed exercise. The first investigations aim at evaluating the effects of an EAA supplementation on muscle mass, architecture, and strength in the early stages of a heavy-load training programme, and at establishing if the enrichment of the supplement with leucine induces greater improvements in these muscle functional adaptations. In a second part, central and peripheral adaptations are examined following training to compare whether EAA supplementation modifies the relative contribution of neural and muscular factors to the increase in muscle torque, and promotes adaptations in muscle mechanical and contractile properties. The purpose of the third investigation is to study the potential effects of an EAA supplementation on the reduction in the efflux of indirect markers of muscle damage and the delayed onset muscle soreness in the week following a heavy-load eccentric training session.In the first and in the second investigation, young males trained for 12 weeks. They were divided into a placebo (PLA) group (n = 14), an EAA group (n = 15) and a leucine (LEU) group (n = 14). At baseline, daily food intakes and nitrogenous balance were assessed with a food questionnaire over 7 days and two 24h urine collections. The effect of training on muscle mass was assessed by anthropometric techniques. Muscle thickness and pennation angle were recorded by ultrasonography of the medial gastrocnemius (MG). Maximal strength during squat and bench press exercises was tested on an isokinetic ergometer. The torque produced by the plantar flexors and the surface electromyogram (EMG) from the soleus (Sol) and MG were recorded during maximal voluntary isometric contractions (MVC). Central activation was tested by the superimposed electrical stimulation method during MVC and by computing the ratio between voluntary average EMG and compound muscle action potential (M wave) induced by electrical stimulation (average EMG/M-wave). Contractile properties of the plantar flexor muscles were investigated by recording the mechanical responses to single and paired maximal stimuli. In the third investigation, young males performed a bench press exercise in eccentric condition. They were subdivided into a PLA group (n=11) and an EAA group (n=12). The effect of the training session was assessed by analysing two indirect markers of muscle damage, namely creatine kinase (CK) and myoglobin (Mb). Plasma concentrations were measured before, immediately after, and on post-workout days 1, 2, 3, 4 and 7. Muscle soreness was evaluated by a visual analogic scale (VAS) at the same time points as the markers of muscle damage.Resistance training resulted in significant increases in muscle mass and strength in all PLA, EAA and LEU groups with no statistical differences between groups. A positive linear regression was found between nitrogen balance and the increase in muscle mass in the PLA group only. When strength was normalised to skeletal muscle mass, negative linear regressions were observed between the normalised initial strength and the increase in muscle strength in both EAA and LEU groups. EAA and LEU ingestion induced changes in MG muscle architecture in response to training. After training, plantar flexor torque recorded during MVC was increased in PLA, EAA and LEU groups. Central activation level was enhanced with no effect of EAA supplementation. Twitch torque evoked by single and paired supramaximal stimuli, maximal rate of torque development to single stimulus and rate of torque relaxation to single and paired stimulus were significantly improved in the LEU group in response to training. The eccentric training session induced a significant increase in muscle soreness in both PLA and EAA groups. Plasma CK release increased significantly at D+3 and D+4 and Mb efflux rose at D+3 in PLA group only. No statistical differences were observed between groups for the two indirect markers of muscle damage. Gaussian distribution was found to be the best fit model for plasma Mb and CK concentration curves. F-test showed that individual curves were statistically distinguishable when comparing the best-fit values of the three parameters (area, SD and mean) between PLA and EAA group data sets (P < 0.01).In summary, the data indicates that EAA supplementation results in similar muscle mass and strength adaptations in response to resistance training with no additional effect by the enrichment of the supplement with LEU. However, the nutritional interventions appear to be more effective in subject having a lower initial nitrogen balance and/or a lower initial strength, potentially by promoting changes in muscle architecture. EAA ingestion does not potentiate neural adaptations, but leucine-enriched EAA supplementation may induce earlier peripheral adaptations, resulting in enhanced torque production and transmission. Finally, EAA supplementation could have minor effects on the overall plasmatic release of indirect markers of muscle damage during the recovery period without any impact on delayed onset muscle soreness. / Doctorat en Sciences de la motricité / info:eu-repo/semantics/nonPublished