Ruddy Richard

Lung cancer: What are the links with oxidative stress, physical activity and nutrition

Oxidative stress appears to play an essential role as a secondary messenger in the normal regulation of a variety of physiological processes, such as apoptosis, survival, and proliferative signaling pathways. Oxidative stress also plays important roles in the pathogenesis of many diseases, including aging, degenerative disease, and cancer. Among cancers, lung cancer is the leading cause of cancer in the Western world. Lung cancer is the commonest fatal cancer whose risk is dependent on the number of cigarettes smoked per day as well as the number of years smoking, some components of cigarette smoke inducing oxidative stress by transmitting or generating oxidative stress. It can be subdivided into two broad categories, small cell lung cancer and non-small-cell lung cancer, the latter is the most common type. Distinct measures of primary and secondary prevention have been investigated to reduce the risk of morbidity and mortality caused by lung cancer. Among them, it seems that physical activity and nutrition have some beneficial effects. However, physical activity can have different influences on carcinogenesis, depending on energy supply, strength and frequency of exercise loads as well as the degree of exercise-mediated oxidative stress. Micronutrient supplementation seems to have a positive impact in lung surgery, particularly as an antioxidant, even if the role of micronutrients in lung cancer remains controversial. The purpose of this review is to examine lung cancer in relation to oxidative stress, physical activity, and nutrition.

Eccentric cycle exercise in severe COPD: feasibility of application.

Eccentric cycling may present an interesting alternative to traditional exercise rehabilitation for patients with advanced COPD, because of the low ventilatory cost associated with lengthening muscle actions. However, due to muscle damage and soreness typically associated with eccentric exercise, there has been reluctance in using this modality in clinical populations. This study assessed the feasibility of applying an eccentric cycling protocol, based on progressive muscle overload, in six severe COPD patients with the aim of minimizing side effects and maximizing compliance. Over 5 weeks, eccentric cycling power was progressively increased in all patients from a minimal 10-Watt workload to a target intensity of 60% peak oxygen consumption (attained in a concentric modality). By 5 weeks, patients were able to cycle on average at a 7-fold higher power output relative to baseline, with heart rate being maintained at ∼85% of peak. All patients complied with the protocol and presented tolerable dyspnea and leg fatigue throughout the study; muscle soreness was minimal and did not compromise increases in power; creatine kinase remained within normal range or was slightly elevated; and most patients showed a breathing reserve > 15 L.min−1. At the target intensity, ventilation and breathing frequency during eccentric cycling were similar to concentric cycling while power was approximately five times higher (p = 0.02). This study showed that an eccentric cycling protocol based on progressive increases in workload is feasible in severe COPD, with no side effects and high compliance, thus warranting further study into its efficacy as a training intervention.

Méthodologie et Pratique de l’Exploration Fonctionnelle à l’eXercice (EFX)

Le Conseil Scientifique de la SPLF nous a demande de reunir un groupe de travail pour elaborer un texte de reference en langue francaise sur les aspects theoriques et pratiques de la methodologie des Explorations Fonctionnelles a l’eXercice (EFX). La pneumologie est une specialite medicale qui appuie largement ses pratiques sur la physiopathologie et les explorations fonctionnelles. Depuis une vingtaine d’annee, l’exploration du sommeil puis celle des reponses fonctionnelles au cours de l’exercice ont contribue au developpement de la specialite. Il etait donc legitime de fournir aux pneumologues un texte de recommandation pour encourager et guider leur enthousiasme grandissant pour une approche physiologique integree des symptomes et des maladies pour les quelles ils sont consultes. Le groupe a ete constitue de pneumologues et de physiologistes d’origine universitaire, hospitaliere, ou liberale ayant une experience etablie dans le domaine de l’exercice, chez l’adulte ou chez l’enfant. Le groupe a travaille de facon continue tout au long de l’annee 2005 2006 avec plusieurs reunions et de tres nombreux echanges electroniques, Apres avoir defini un plan tres detaille, le travail de bibliographie et d’ecriture a ete reparti en fonction de l’experience de chacun. Chaque chapitre a fait l’objet d’une lecture critique en groupe, permettant de mieux preciser certains points et de proposer un texte qui ne soit pas l’avis d’un seul expert, mais qui reflete l’accord de tous en prenant en compte les donnees de la litterature scientifique. Plusieurs reunions de mise au point ont ete necessaires. La mise en forme finale et l’homogeneite du texte complet ont ensuite ete soigneusement revues par deux membres du groupe. Une lecture critique collective de ce texte a finalement permis d’obtenir un consensus sur le contenu et de s’accorder sur les contrastes qu’il fallait donner a ce texte. Chaque membre a eu par la suite, le temps de revoir l’integralite du texte pour une ultime verification. Une fois finalise ce texte a ete confie a deux physiologistes internationalement reconnus pour leur competence scientifiMots-cles : Exercice • Evaluation • Pneumologie • Test exercice • Methodologie.

Adaptation du transport cardiocirculatoire à l’exercice

This article examines the expected exercise-induced changes in the components of the oxygen transport system as described by the Fick equation with a view to enable a critical analysis of a standard incremental exercise test to identify normal and abnormal patterns of responses and generate hypotheses as to potential physiological and/or pathophysiological causes. The text reviews basic physiological principals and provides useful reminders of standard equations that serve to integrate circulatory, respiratory and skeletal muscle functions. More specifically, the article provides a conceptual and quantitative framework linking the exercise-induced increase in whole body oxygen uptake to central circulatory and peripheral circulatory factors with the view to establish the normalcy of response. Thus, the article reviews the exercise response to cardiac output determinants and provides qualitative and quantitative perspective bases for making assumptions on the peripheral circulatory factors and oxygen use. Finally, the article demonstrates the usefulness of exercise testing as an effective integrative physiological approach to develop clinical reasoning or verify pathophysiological outcomes.

Effect of prehabilitation in gastro-oesophageal adenocarcinoma: study protocol of a multicentric, randomised, control trial—the PREHAB study

Introduction Perioperative chemotherapy is the gold standard treatment of the resectable gastro-oesophageal adenocarcinoma. However, 70% of patients cannot receive the complete sequence because of a postoperative complication or a decrease in functional and nutritional reserves. Recently, a new concept appeared in digestive surgery: prehabilitation. This interventional process consists of patient preparation, between surgical consultation and surgery, and is based on 3 components: (1) physical management, (2) nutritional care and (3) psychological care. Prehabilitation should decrease postoperative complications and improve nutritional and physical status during the preoperative and postoperative periods. Therefore, it is becoming essential to evaluate the effect of prehabilitation, compared to conventional care, on the percentage of patients reaching the complete oncological treatment. Methods and analysis The PREHAB trial aimed to evaluate the efficacy of prehabilitation compared to conventional care, in patients with gastro-oesophageal cancer with perioperative chemotherapy. This trial is a prospective, randomised, controlled, open-blind and interventional study in 4 centres. Patients (n=60 per group) will be randomly assigned for management with either prehabilitation or conventional care. The primary outcome is the percentage of patients reaching the complete oncological treatment decided in a multidisciplinary tumour board. The secondary outcomes are the postoperative morbidity, disease-free survival, overall survival, feasibility of the protocol, length of stay, variation of the functional reserve after the preoperative chemotherapy (defined by the VO2peak, ventilatory threshold and 6-min walk test), preoperative and postoperative nutritional status, preoperative anxiety, quality of life, 30-day and 90-day mortality and cumulative dose of cytotoxic treatment received. Ethics and dissemination The study was approved by an independent medical ethics committee (IRB00008526, CPP Sud-Est VI, Clermont-Ferrand, France) and by the competent French authority (ANSM, Saint Denis, France) and registered on Clinicaltrial.gov. The results will be disseminated in a peer-reviewed journal. Trial registration number NCT02780921.

Exercise Cardiac Output Limitation in Pectus Excavatum.

Indication of pectus excavatum (PE) surgical treatment is a much-debated subject, especially regarding functional impact of the deformation. The pulmonary consequences of PE have been found not to be the limiting factor in exercise for these patients. On the other hand, the hemodynamic consequences

RecommandationsMéthodologie et Pratique de l’Exploration Fonctionnelle à l’eXercice (EFX)

Le Conseil Scientifique de la SPLF nous a demandé de réunir un groupe de travail pour élaborer un texte de référence en langue française sur les aspects théoriques et pratiques de la méthodologie des Explorations Fonctionnelles à l’eXercice (EFX). La pneumologie est une spécialité médicale qui appuie largement ses pratiques sur la physiopathologie et les explorations fonctionnelles. Depuis une vingtaine d’année, l’exploration du sommeil puis celle des réponses fonctionnelles au cours de l’exercice ont contribué au développement de la spécialité. Il était donc légitime de fournir aux pneumologues un texte de recommandation pour encourager et guider leur enthousiasme grandissant pour une approche physiologique intégrée des symptômes et des maladies pour les quelles ils sont consultés. Le groupe a été constitué de pneumologues et de physiologistes d’origine universitaire, hospitalière, ou libérale ayant une expérience établie dans le domaine de l’exercice, chez l’adulte ou chez l’enfant. Le groupe a travaillé de façon continue tout au long de l’année 2005 2006 avec plusieurs réunions et de très nombreux échanges électroniques, Après avoir défini un plan très détaillé, le travail de bibliographie et d’écriture a été réparti en fonction de l’expérience de chacun. Chaque chapitre a fait l’objet d’une lecture critique en groupe, permettant de mieux préciser certains points et de proposer un texte qui ne soit pas l’avis d’un seul expert, mais qui reflète l’accord de tous en prenant en compte les données de la littérature scientifique. Plusieurs réunions de mise au point ont été nécessaires. La mise en forme finale et l’homogénéité du texte complet ont ensuite été soigneusement revues par deux membres du groupe. Une lecture critique collective de ce texte a finalement permis d’obtenir un consensus sur le contenu et de s’accorder sur les contrastes qu’il fallait donner à ce texte. Chaque membre a eu par la suite, le temps de revoir l’intégralité du texte pour une ultime vérification. Une fois finalisé ce texte a été confié à deux physiologistes internationalement reconnus pour leur compétence scientifiMots-clés : Exercice • Évaluation • Pneumologie • Test exercice • Méthodologie.

A new equation based on the 6-min walking test to predict VO 2peak in women with obesity

Abstract Objective: The 6-min walking test (6 MWT) is commonly used to assess obese patients’ aerobic fitness, but it has rarely been compared with a direct measurement of maximal aerobic capacities (VO2max or VO2peak) in obese adults. The aim of this study was to investigate the relationship between the distance covered during a 6 MWT with objectively measured VO2peak and to propose a new equation to predict VO2peak from this walking test in obese patients. Methods: One hundred and thirty-seven obese patients (45.6 ± 12.5 years) admitted to our hospital for a multidisciplinary rehabilitation program were enrolled. After assessment of their body composition, the participants were asked to perform a 6 MWT and their maximal aerobic capacities (VO2peak) were measured. Result: There is a significant linear relation between VO2peak and the distance covered during the 6 MWT (p < 0.001; r = 0.349). The determinant of VO2peak was body mass index, waist-to-hip ratio, fat free mass, leading to the follow prediction equation VO2peak such as VO2peak (l/min) = (body mass index ×0.0150065) − (waist-to-hip-ratio × 0.8595088) + (fat-free-mass × 0.0295478) + (6-min walk test ×0.0020672) − 0.5853372. Conclusion: The 6-min walk test is a reliable method to reflect obese women’s aerobic capacities and the distance covered can be used to accurately estimate VO2peak according to our newly proposed equation. Implication for rehabilitation Obesity is a worldwide disease and physical capacity evaluation is a key point for rehabilitation. The six minutes’ walk test is commonly used in obese people to assess aerobic fitness. This study proposes a new equation using 6 MWT performance to estimate VO2peak.

Eccentric cycling is more efficient in reducing fat mass than concentric cycling in adolescents with obesity: XXXX

The benefits of eccentric (ECC) training on fat mass (FM) remain underexplored. We hypothesized that in obese adolescents, ECC cycling training is more efficient for decreasing whole‐body FM percentage compared to concentric (CON) performed at the same oxygen consumption (VO2). Twenty‐four adolescents aged 13.4 ± 1.3 years (BMI > 90th percentile) were randomized to ECC or CON. They performed three cyclo‐ergometer sessions per week (30 min per session) for 12 weeks: two habituation, 5 at 50% VO2peak, and 5 at 70% VO2peak. Anthropometric measurements, body composition, maximal incremental CON tests, strength tests, and blood samples were assessed pre‐ and post‐training. Whole‐body FM percentage decreased significantly after compared to pretraining in both groups, though to a larger extent in the ECC group (ECC: −10% vs CON: −4.2%, P < 0.05). Whole‐body lean mass (LM) percentage increased significantly in both groups after compared to pretraining, with a greater increase in the ECC group (ECC: 3.8% vs CON: 1.5%, P <0.05). The improvements in leg FM and LM percentages were greater in the ECC group (−6.5% and 3.0%, P = 0.01 and P < 0.01). Quadriceps isometric and isokinetic ECC strength increased significantly more in the ECC group (28.3% and 21.3%, P < 0.05). Both groups showed similar significant VO2peak improvement (ECC: 15.4% vs CON: 10.3%). The decrease in homeostasis model assessment of insulin resistance index was significant in the ECC group (−19.9%). In conclusion, although both ECC and CON cycling trainings are efficient to decrease FM, ECC induces greater FM reduction, strength gains, and insulin resistance improvements and represents an optimal modality to recommend for obese adolescents.

Eccentric Training Improves Body Composition by Inducing Mechanical and Metabolic Adaptations: A Promising Approach for Overweight and Obese Individuals

Skeletal muscle generates force by either shortening (concentrically) or lengthening (eccentrically). Eccentric (ECC) exercise is characterized by a lower metabolic demand and requires less muscle activity than concentric (CON) exercise at the same level of exerted force. However, the specific effect of ECC training vs. CON training on lean and fat mass remains underexplored. The first aim of this paper was to review the available evidence regarding the effects of ECC training on whole body and segmental lean and fat mass and, when possible, compare these with the effects of CON training. The second aim was to provide some insights into the main mechanical, physiological, and metabolic adaptations of ECC training that contribute to its effects on body composition. The third aim was to determine the beneficial effects of ECC exercise on health-related parameters in overweight and obese patients. ECC training is an effective modality to improve lean mass, but when matched for load or work, the difference between ECC and CON trainings seems unclear. A few studies reported that ECC training is also efficient at reducing fat mass. By increasing post-exercise resting energy expenditure, modifying metabolic substrate, and improving both blood lipid profile and insulin resistance, ECC training is a potential exercise modality for individuals with chronic conditions such as those who are overweight and obese. Further investigations using standardized experimental conditions, examining not only segmental but also whole body composition, are required to compare ECC and CON trainings.