Problem: Walking cadence (steps/minute) is used to prescribe walking intensity. For healthy adults, the recommended cadence is generally 100 steps per minute to reach moderate intensity. However, the required walking cadence to reach that intensity for people having risk factors for cardiovascular diseases (CVD) is unknown. Methods: Ninety-one people presenting risk factors for CVD completed a graded exercise test to assess maximum oxygen consumption. In a separate session, when participants reached moderate intensity based on their maximum oxygen consumption, walking cadence was recorded. Results: Mean walking cadence to reach moderate intensity was 115.8 ± 10.3 steps per minute. Using linear regression analysis, only body weight (ß=0.24; P=0.018) significantly predicted the walking cadence required to reach moderate intensity. Conclusions: The walking cadence needed for people presenting risk factors for CVD to reach moderate intensity is about 116 steps per minute. Body weight influences the walking cadence needed to reach moderate intensity. / October 2015

abstract: Obesity prevalence is high in the United States, in part due to increased fat storage following consumption of high fat/carbohydrate (sugar) foods. Following a meal, carbohydrate stimulates its own oxidation, while simultaneously suppressing fat oxidation, ultimately leading to fat storage. Aerobic exercise preceding a meal increases fat oxidation in the postprandial period, which may reduce fat storage. The ideal exercise prescription for optimal postprandial fat oxidation is unknown. The effect of low and moderate intensity continuous exercise (MIE) has been studied extensively, while the effects of high-intensity interval exercise (HIIE) on post-prandial substrate oxidation has not been examined. The purpose of this study was to compare the effects of MIE and HIIE on postprandial substrate oxidation after consumption of an isocaloric meal (2 glazed donuts; 520 kcal) in healthy adults. Ten subjects (8 males, 2 females; age=24yr, BMI=24 kg/m2) completed three conditions in random order: 1) no exercise control; 2) MIE: cycling at 60-75%HRmax; 3) HIIE: cycling at 90-95%HRmax. The duration of each exercise bout was sufficient to expend approximately 520 kcal, the energy equivalent of the donuts, which were consumed 1 hour post-exercise. Immediately after consuming the donuts, pulmonary ventilation and gas exchange were measured breath-by-breath continuously and recorded (min-by-min) for 5 hours. Repeated measures analysis of covariance was used to compare the mean differences in outcome variables accounting for gender. Absolute postprandial fat oxidation (g/5 hours) was 17.3±5.4, 27.1±9.6 and 23±1.2 for control, MIE and HIIE trials respectively, with the postprandial fat oxidation significantly greater for the two exercise conditions compared to control. Relative to baseline values, both exercise conditions resulted in cumulative net postprandial fat oxidation significantly greater than control (control = -1.79±3.99g; MIE = 11.51±8.41g, HIIE= 9.51±5.20g). Therefore, results indicate that exercise most certainly increases postprandial fat oxidation, and that exercise type, either MIE or HIIE, is not as important as total energy expended. The fact that exercise of ~1 hour was required to oxidize the amount of fat in two donuts, that required only a few minutes to consume, highlights the challenges of using exercise for weight control in an obesogenic environment. / Dissertation/Thesis / Masters Thesis Nutrition 2018

abstract: The winter holiday period has been highlighted as a major risk period for weight gain due to excess caloric intake in the form of fat and sugar. Furthermore, diets high in fat and sugar have been implicated in the pathogenesis of diabetes and cardiovascular disease. Exercise aids in the prevention of weight/fat gain, and prevents deleterious changes in cardiometabolic function. The objective of this study was to examine the effects of a fat-sugar supplemented diet, with and without two different exercise training protocols, on body composition, glycemic control and other markers of cardiovascular disease in an at-risk population of overweight and obese males. Twenty-seven, healthy overweight/obese (BMI >25 kg/m2) males were fed 2 donuts per day, 6 days/week, for four weeks, while maintaining their current diet. In addition, all subjects were randomized to one of the following conditions: sedentary control, 1,000 kcal/week moderate-intensity continuous training (MICT) (50% of peak oxygen consumption), or 1,000 kcal/week high-intensity interval training (HIIT) (90-95% of peak heart rate). Supervised exercise training was performed 4 days/week on a cycle ergometer. Changes in body weight and composition, endothelial function, arterial stiffness, glycemic control, blood lipids and cardiorespiratory fitness (CRF) were assessed before and after the intervention. Body weight, lean mass and visceral fat increased significantly in HIIT (p<0.05) and were unchanged in MICT. There was a trend for a significant increase in body weight (p=0.07) and lean mass (p=0.11) in control. Glycemic control during the 2-h OGTT improved significantly in MICT and control, with no change in HIIT. Hepatic insulin resistance index (IRI) and 30-min insulin during the OGTT improved significantly after MICT and worsened following control (p=0.03), while HIIT was unchanged. CRF increased significantly in both HIIT and MICT, with no change in control (p<0.001). There were no significant changes in other markers of cardiovascular disease. The addition of a fat-sugar supplement (~14,500 kcal) over a 4-week period was not sufficient to induce deleterious changes in body composition and cardiometabolic health in overweight/obese young males. Exercise training did not afford overweight/obese males additional health benefits, with the exception of improvements in fitness and hepatic IRI. / Dissertation/Thesis / Doctoral Dissertation Physical Activity, Nutrition and Wellness 2016

Research hypothesis The dependence of maximal and submaximal indices of aerobic fitness and cardio respiratory system function on the type of ergometry will change due to specific impact of slow adaptation of the researched athletes. The functional indices of persons of different athletic fitness and sports specialization responsible for general adaptation of the human body to physical loads should vary less performing different continuously increasing loads or constant physical loads compared to those fitness indices which more depend on the adaptation specificity of trained muscles. The aim of the research was to establish the peculiarities of indices of athletes’ aerobic fitness and cardio respiratory system function in dependence on ergometry and the specificity of slow adaptation. Research objectives: 1. To compare maximal and submaximal values of indices of cardio respiratory system function of swimmers and untrained persons during cycling and arm ergometry. 2. To compare maximal values of indices of cardio respiratory system function of athletes in dependence on ergometry and the specificity of slow adaptation. 3. To compare submaximal values of indices of cardio respiratory system function of athletes in dependence on ergometry and the specificity of slow adaptation. 4. To compare the changes in the indices of cardio respiratory system function of athletes in the transitional phases of different constant physical load in dependence on ergometry and the specificity of... [to full text] / Tyrimo hipotezė. Maksimalių ir submaksimalių aerobinio pajėgumo ir vegetacinių sistemų funkcijos rodiklių priklausomumas nuo ergometrijos pobūdžio pakis dėl specifinio tiriamų sportininkų lėtos adaptacijos poveikio. Skirtingo treniruotumo ir sportinės specializacijos asmenų organizmo funkcijos rodikliai, atsakingi už bendrąją organizmo adaptaciją fiziniams krūviams, turėtų mažiau skirtis atliekant skirtingo pobūdžio nuosekliai didinamus ar pastovius fizinius krūvius, negu tie pajėgumo rodikliai, kurie labiau priklauso nuo treniruojamų raumenų adaptacijos specifikos. Tyrimo tikslas - nustatyti sportininkų aerobinio pajėgumo ir vegetacinių sistemų funkcijos rodiklių ypatumus priklausomai nuo ergometrijos ir lėtosios adaptacijos specifikos. Tyrimo uždaviniai: 1. Palyginti plaukikų ir nesportuojančių asmenų maksimalias ir submaksimalias vegetacinių sistemų funkcijos rodiklių reikšmes įvairaus pobūdžio darbe. 2. Palyginti sportininkų maksimalias vegetacinių sistemų funkcijos rodiklių reikšmes įvairaus pobūdžio darbe priklausomai nuo ergometrijos ir lėtosios adaptacijos specifikos. 3. Palyginti sportininkų submaksimalias vegetacinių sistemų funkcijos rodiklių reikšmes įvairaus pobūdžio darbe priklausomai nuo ergometrijos ir lėtosios adaptacijos specifikos. 4. Palyginti sportininkų vegetacinių sistemų funkcijos rodiklių kaitą pereinamosiose pastovaus intensyvumo įvairaus pobūdžio darbo fazėse priklausomai nuo ergometrijos ir lėtosios adaptacijos specifikos. Tyrimo rezultatų... [toliau žr. visą tekstą]

L’exercice fractionné de haute intensité (HIIT) et continu d’intensité modéré (MOD) représentent les 2 grandes modalités d'endurance. Cependant, leur impact spécifique sur la performance physique et la plasticité cérébrale et musculaire reste controversé du fait de la diversité des protocoles d’exercice proposés chez les sédentaires. Notre 1er axe dégage chez des rats sains l’effet de ces 2 modalités sur la performance physique, la plasticité musculaire et cérébrale sur 8 semaines d’entrainement standardisée dont l'intensité est basées sur le seuil lactique. Nos résultats montrent des gains de performance d’endurance plus rapides et importants suite aux HIIT. La neuroplasticité serait stimulée par les HIIT uniquement et la plasticité musculaire semble spécifique à chacune. L’engouement pour les HIIT se répercute chez les patients subissant un accident vasculaire cérébral où l’efficacité des méthodes d’endurance n’est pas clairement justifiées. Une étude antérieure a montré l’intérêt majeur des HIIT dans la phase aiguë de la pathologie malgré une récupération sensorimotrice incomplète. D’où l’intérêt d’approfondir dans notre second axe l’effet des différentes formes de HIIT (longs et courts) dans la récupération. Nos résultats montrent principalement que ces deux formes de HIIT améliorent la capacité d’endurance et la force de la patte antérieure lésée avec une précocité pour les HIIT longs. Les deux formes de HIIT semblent induire une angiogenèse cérébrale. Néanmoins, ils n’améliorent pas les fonctions sensorimotrices et cognitives. Ainsi, il est nécessaire d’approfondir les répercussions de ces deux entrainements HIIT dans la plasticité musculaire et cérébrale. / Endurance exercise is essential for different reasons in athlete and also in aging and pathological people. Two training modalities were found: high intensity interval training (HIIT) and moderate intensity aerobic training (MOD). However, the specific outcomes of these modalities on physical performance and cerebral and muscular plasticity are controversial because many exercise protocols exist. The 1st study explore the impact of these 2 training on endurance and functional capacity and also on muscular and cerebral molecular modifications throughout 8 weeks in healthy rats. HIIT and MOD programs are work-matched and training intensity are determined thanks to the lactate threshold. Our results show a superior and fast effect on endurance capacity after HIIT compared to MOD. Hippocampal plasticity is stimulated only after HIIT and muscular modifications appear to be specific to each modality. A great interest of HIIT is found in stroke patients for whom evidence of endurance modalities efficiency is still missing. A previous study has shown a beneficial effect of HIIT in the acute phase of stroke despite incomplete sensorimotor recuperation. Hence, the interest to deepen in second part of this manuscript the impact of two HIIT modalities (short and long) in recovery optimisation. Our results show that 2 HIIT strongly improve endurance performance and strength of injured paw with a fast effect for long HIIT. The 2 modalities seem to induce cerebral angiogenesis. However, these 2 training do not increase sensorimotor and cognitive functions. In perspective, it appears necessary to develop muscular and cerebral outcomes induced by these 2 HIIT modalities.

Background: There are over 300 Primary Immunodeficiency diseases (PID) that are a result of a genetic or idiopathic dysfunction of any aspect of the immune system. These conditions result in a higher frequency of infections, autoimmune conditions, or malignancies. Moderate intensity exercise is thought to help the immune system, while high intensity exercise may have a negative impact on immune function. The impact of exercise on individuals with an impaired immune system due to PID is not yet understood. Purpose: The purpose of this study was to investigate whether a low to moderate intensity exercise program would have an effect on stress, fatigue, and quality of life (QoL) for individuals diagnosed with PID. Methods: 34 participants were included in this eight-week, mixed-methods, randomized controlled trial, either as part of the control group, or as part of the exercise intervention group. Participants completed pre- and post-study outcome measures, reflective journaling, and a post-study interview. Results: There were no statistically significant differences between the groups for the outcome measures, infection incidence, or need for non-routine medical care. There was a clinically significant decline in the Physical Component Summary score of the SF-36v2 for the control group at the end of the study. The scores for the SF-36v2, for all participants, were below normative scores for all domains, at the beginning and end of the study. Four main themes emerged from the qualitative interviews: living with a ‘new normal’, the challenges of living with a chronic disease, facing the stigma of a chronic disease, and wanting to exercise, but were too exhausted to do so. Conclusions: Individuals with a diagnosis of PID have lower QoL scores as compared to population norms. They face high levels of stress, overwhelming fatigue, social isolation, and decreased emotional well-being. Exercise programs for this patient population did not result in increased infections or need for non-routine medical care but did result in emotional implications that need to be considered. Healthcare providers need to address emotional well-being and provide coping strategies. Exercise programs should be designed with a slow, methodical ramp-up to avoid increasing fatigue or stress, while exercise goals must be highly achievable and realistic. Physical therapists should collaborate with other healthcare professionals for a more holistic and interprofessional approach to working with patients with a diagnosis of PID.

No description available.

Au laboratoire comme sur le terrain, le choix de la cadence lors de l’exercice de pédalage est un élément important dans la réalisation d’un exercice. De nombreux travaux ont porté sur l’effet de la cadence de pédalage sur différents aspects tels que la performance, les paramètres cardiorespiratoires, la participation du métabolisme « anaérobie » et le recrutement musculaire. Cependant, très peu de travaux ont étudié l’effet de la cadence de pédalage sur la disponibilité et l’utilisation d’O2 au niveau musculaire et cérébral. L’objectif principal de cette thèse était de comprendre les effets de la cadence de pédalage sur la disponibilité en O2 ainsi que l’utilisation d’O2 au niveau musculaire et cérébral. Le but de nos trois plans expérimentaux était d’étudier d’une part l’effet de la cadence de pédalage sur l’hétérogénéité de la déoxygénation musculaire lors de l’exercice modéré et d’autre part l’effet de la cadence sur l’oxygénation musculaire et cérébrale et sur la performance lors de l’exercice intense chez des sujets non entraînés ainsi que chez des sujets entraînés à l’endurance.Ce travail nous a permis de montrer que, lors de l’exercice d’intensité modérée, V ̇O2 de l’organisme entier et l’hétérogénéité de la déoxygénation musculaire étaient plus élevées à cadence élevée qu’à cadence faible, bien que la déoxygénation n’était pas modifiée par la cadence de pédalage chez les sujets non entraînés à l’endurance. D’autre part, lors de l’exercice intense mené jusqu’à l’épuisement, la performance était améliorée à 40 rpm par rapport à 100 rpm chez les sujets non entraînés tandis qu’aucune différence significative n’était observée entre les deux cadences chez les triathlètes. De plus, l’extraction d’O2 au niveau du vastus lateralis était dépendante de la cadence de pédalage chez les sujets non entraînés mais ne l’était pas chez les sujets entraînés à l’endurance. Enfin, nous avons observé un effet de la cadence de pédalage sur l’oxygénation cérébrale et en particulier une possible élévation de la disponibilité en O2 au niveau cérébral à faible cadence de pédalage chez les deux populations. Pour conclure, ce travail nous a permis de mettre en évidence des différences liées à l’aptitude aérobie des sujets et à l’intensité de l’exercice dans les réponses de l’oxygénation cérébrale et musculaire et de la performance lors d’exercices effectués à différentes cadences. / Choosing the pedalling cadence during the cycling exercise, in the laboratory as well as on the field, is a crucial element in fulfilling an exercise. Many studies have examined the effect of pedal cadence on various aspects such as performance, cardiorespiratory parameters, the participation of the “anaerobic” metabolism and muscle recruitment. However, few studies have investigated the effect of pedal cadence on the O2 availability and its utilization in the muscle as well as in the brain. This is why the main objective of this thesis was to understand this subject which is underdeveloped. The aim of our three experimental procedures was on one hand to study the effect of pedal cadence on the heterogeneity of the muscle’s deoxygenation during moderate exercise. On the other hand, to study the effects of pedal cadence on muscle and cerebral oxygenation and also on the performance during heavy exercise in untrained subjects, as well as in endurance-trained subjects.This work allows us to show that at moderate-intensity exercise, whole body V ̇O2 and the heterogeneity of muscle deoxygenation were higher at high cadence than at a lower one, even if the deoxygenation was not altered by the pedalling cadence in non-endurance-trained subjects. On the other hand, during intense exercise performed until exhaustion, the performance improved at 40 rpm than at 100 rpm in untrained subjects, while no significant difference was observed between the two cadences among triathletes. In addition, the O2 extraction in the vastus lateralis depended on the pedal cadence in untrained subjects and the opposite in endurance-trained subjects. Finally, we observed an effect of pedal cadence on cerebral oxygenation and in particular a possible rise in the availability of O2 in the brain on a lower cadence in both population levels. In conclusion, this work has allowed us to highlight the differences in the aerobic fitness of the subjects and in the intensity of the exercise in brain and muscle oxygenation responses and performance during exercises performed at different cadences.