Title: Movement economy and physiological response during differing climbing speeds in sport climbers. Aims: The work aims to evaluace climbing economy and physiological responses of intermediate and advanced climbers in different climbing speeds. Methodology: 32 climbers (11 advanced men, 11 intermediate men, 10 intermediate women) performed 3 submaximal tests in treadwall at slope of 90ř at speeds 4, 6 and 9 m.min-1 . Each of the tests lasted exactly 4 minutes. Oxygen consumption (VO2), heart rate (HR), ventilation (VE), respiratory ratio (RER) and energy expenditure were monitored. Results: Advanced men reported lower energy expenditure than intermediate men in all climbing speeds (4 m.min-1 : -0,06 kcal.kg-1 , P = 0,007; 6 m.min-1 : -0,06 kcal.kg-1 P = 0,048; 9 m.min-1 : -0,07 kcal.kg-1 P = 0,022). Intermediate women reported only slightly lower energy expenditure than intermediate men (4 m.min-1 : -0,01 kcal.kg-1 P = 0,051; 6 m.min-1 : 0,06 kcal.kg-1 P = 0,091; 9 m.min-1 : -0,03 kcal.kg-1 P = 0,115). Energy expenditure was significantly lower at 4 m.min-1 than at 6 m.min-1 (-9,82 kcal, p = 0,001) and also signicantly lower at 6 m.min-1 than at 9 m.min-1 (-8,3 kcal, p = 0,001). Advanced men reported significantly lower VO2 at speeds 4 a 6 m.min-1 (- 2,2 ml.kg- 1 .min-1, P = 0,022; -3,9 ml.kg-1...

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Bakgrund: Styrketräning är en viktig träningsform som medför flertalet hälsofördelar som minskad risk för sjukdomar och bättre hälsa. Forskning har visat att styrketräning ökar energiförbrukning under och efter träning. Marklyft är en helkroppsövning som har stor effekt inom styrketräning. Till författarnas vetskap har inga tidigare studier undersökt akut energiförbrukning (EE) och syreupptagning (V’O2) under marklyft med samma totala träningsvolym. Syfte: Syftet med studien var att ta reda på effekterna av akut respons av V’O2 och energiförbrukning under marklyft med två intensiteter men samma totala volym. Metod: 7 manliga deltagare rekryterades med en medelålder på 23,7. Testerna och datainsamlingen genomfördes under 3 separata tillfällen genom viloomsättnings-tester följt av marklyftstester och återtest. Deltagarna utförde ett set av 40% 1RM x 10 repetitioner under 30 sekunder och ett set av 80% 1RM x 5 repetitioner under 30 sekunder. Mellan 40% och 80% tester hade deltagarna 7 minuters vila. Resultat: Det visade tendenser till att 80% 1RM ökar energiförbrukningen och kräver högre V’O2 än 40% 1RM under arbetsfasen. Återhämtningsfasen visade signifikant skillnad i energiförbrukning mellan 40% 1RM och 80% 1RM (p=0,007). Återhämtningen visade även en signifikant skillnad i V’O2 mellan 40% 1RM och 80% 1RM (p=0,028). Slutsats: Studien indikerar att marklyft vid hög belastning resulterar i högre energiförbrukning och ökad V’O2 till jämfört med lägre belastning under arbetsfasen och återhämtningsfasen. / Background: Strength training is an important method of training that brings several health benefits including reduced risk of diseases and a better wellness. Studies have shown that strength training increases energy expenditure (EE) during and after training. Deadlift is a compound exercise which has a big impact within strength training. To the knowledge of the authors no studies has looked into the differences in EE and VO’2 during deadlift with the same amount of volume. Aim: The aim of this study was to examine acute response of V’O2 and EE during deadlift with two different intensities but same total amount of volume (dose). Method: 7 male participants were recruited with a mean age of 23,7. Testing and data collection were done on 3 separate occasions through RMR-testing followed by deadlifts and retest. The participants did one set of 40% 1RM x 10 repetitions under 30 seconds and one set of 80% 1RM x 5 repetitions under 30 seconds. In between 40% and 80% tests, the participants had 7 minutes of rest. Results: It shows tendencies that 80% 1RM increase EE more than 40% 1RM during workout phase. It also show tendencies that 80% 1RM demand higher V’O2 than 40% 1RM under the workout phase. Recovery phase showed a significant difference in EE between 40% 1RM and 80% 1RM (p=0,007). Recovery phase also showed a significant difference in V’O2 between 40% 1RM and 80% 1RM (p=0,028). Conclusion: The study shows that deadlift with heavier load result in higher EE and increased V’O2 compared to a lower load during the workout phase and recovery phase.

Le trail running, course nature de distances, dénivelés et technicités variables, est une discipline récente à la popularité croissante. La performance en trail dépend de nombreux facteurs génétiques, énergétiques, techniques, stratégiques et motivationnels. Parmi ces facteurs, le coût énergétique de la locomotion fait débat. Les études de cette Thèse s'attachent aux corrélations plat/montée de cette variable, au calcul d'un coût en pente à partir d'un coût à plat, à l'influence de la modification forcée de la fréquence de foulée sur l'énergie consommée, et à l'impact de la fatigue générée par un ultra trail sur le coût à plat et en montée. La prise en compte des contraintes musculaires et biomécaniques en trail d'une part, des facteurs influençant l'économie de course d'autre part, ainsi que des résultats de notre principale étude de terrain, nous laissent émettre l'hypothèse que le coût énergétique et ses variations pre/post course à plat/montée, ne sont pas des indicateurs de performance de l'activité. La force, l'endurance de force et le pacing, en plus de la puissance aérobie et de l'endurance, sont les variables testées les mieux corrélées à la performance en ultra trail / Trail running is a discipline with increasing popularity over the last 2 decades. Trail performance depends on many genetic, energetic, technical, strategic and motivational factors. Among these factors, the energy cost of locomotion is debated. The studies in this Thesis focus on the level/graded correlations of this variable, on the calculation of an uphill cost from a level cost, on the influence of a forced modification of stride frequency on running economy, and on the impact of fatigue generated by an ultra trail on level and uphill costs. Taking account of the muscular and biomechanical constraints on the one hand, and the factors influencing the running economy on the other hand, as well as the results of our main field study, we hypothesize that energy cost and its pre/post fatigue variations, are not performance indicators of the activity. Force, endurance of force and pacing, in addition to aerobic power and endurance, are the tested variables best correlated to ultra trail performance

O acúmulo intramuscular de íons H+ decorrente do exercício de alta intensidade inibe enzimas da via glicolítica, além de prejudicar diversas etapas do processo contrátil levando à fadiga. Especula-se que a suplementação combinada de betaalanina (via aumento da concentração de carnosina) e bicarbonato de sódio aumentaria a capacidade tamponante intra e extracelular refletindo em efeitos sinérgicos no metabolismo energético e no desempenho, do que quando suplementados isoladamente. Poucos estudos investigaram a eficácia da combinação dos suplementos durante o exercício e não há informações sobre os efeitos desta combinação nos sistemas energéticos. Portanto, esse estudo teve por objetivo investigar a eficácia da suplementação combinada ou isolada de betaalanina e bicarbonato de sódio enquanto estratégias de aumento da capacidade tamponante, bem como seu potencial na modulação do metabolismo energético e no desempenho do exercício intermitente de alta intensidade. O estudo contou com um desenho duplo-cego em que 77 voluntários (idade 38,6 ± 9,9 anos; massa corporal 76,6 ± 8,4 kg; VO2pico 59,3 ± 5,2 ml.kg-1.min-1) foram randomizados e aleatoriamente alocados em um dos 4 grupos sendo; beta-alanina (BA; n= 19), bicarbonato de sódio (BIC; n = 19), beta-alanina e bicarbonato de sódio (BA + BIC; n = 20) ou dextrose (PLA; n = 19). A eficácia das substâncias na contribuição dos sistemas energéticos foi comparada antes e após um período de 28 dias de suplementação de 6,4g/dia de beta-alanina e de 0,3g/kg de massa corporal de bicarbonato de sódio administrada 60 minutos antes de um exercício intermitente em cicloergômetro, que consistia de 4 séries de 1 minuto a 110% da potência aeróbia máxima com 1 minuto de intervalo e cadência constante. Após 10 minutos de repouso passivo, o desempenho era avaliado em um teste time-trial cuja meta era completar um trabalho total de 30 kJ, no menor tempo possível. Foram mensuradas as concentrações sanguíneas de pH, bicarbonato, excesso de base e lactato antes, durante e após os exercícios. As frações dos sistemas oxidativo e alático (ATP-CP) foram estimadas com base no consumo de oxigênio e o glicolítico pelo delta da concentração do lactato. O perfil energético do exercício intermitente consistiu na maior parte do sistema oxidativo (45 - 55%), seguido do sistema ATP-CP (35 - 40%) e do glicolítico (8 - 15%). A suplementação de bicarbonato de sódio elevou (P<0,001) as concentrações sanguíneas de bicarbonato (~ 6 mmol/L) e pH (~ 0,06 unidades) nos grupos BIC e BA + BIC, gerando uma maior concentração do lactato nas séries iniciais o que refletiu no aumento do custo energético glicolítico na primeira série do exercício intermitente, sendo estatisticamente significativo somente no grupo BIC (9,9 ± 7,2 kJ vs 18,7 ± 9,4 kJ; pré vs pós-suplementação). Não houve efeito da suplementação no tempo para completar o time-trial entre os grupos ou períodos de suplementação (BA -0,5%; BIC -1,4%; BA + BIC -4% e PLA 0%). A suplementação de bicarbonato de sódio, independentemente da suplementação de beta-alanina melhorou as variáveis de controle do equilíbrio ácido-base sanguíneo resultando na maior participação da via glicolítica, entretanto não conferiu benefícios adicionais ao desempenho / Intramuscular accumulation of H+ ions during high-intensity exercise inhibits glycolytic pathway enzymes and impairs several steps in the muscle-contraction process, causing fatigue. It has been suggested that a combined supplementation of betaalanine (through an increase in carnosine concentration) and sodium bicarbonate would increase intra- and extracellular buffering capacity causing synergetic effects on energy metabolism and performance, more than each supplement alone. Few studies investigate the effectiveness of combined supplements during exercise and there is no literature on the effects of this combination on energy system contribution. Therefore, the present study investigated the effectiveness of both beta-alanine and sodium bicarbonate alone and together in increasing buffering capacity as well as the potential for modulating energy metabolism and performance during high-intensity intermittent exercise. The study was double-blind and 77 volunteers (aged 38.6 ± 9.9 year, body mass 76.6 ± 8.4 kg; VO2peak 59,3 ± 5,2 ml.kg-1.min-1) were randomly assigned to four groups: beta-alanine (BA; n = 19), sodium bicarbonate (BIC; n = 19), beta-alanine and sodium bicarbonate (BA + BIC; n = 20), dextrose (PLA; n = 19). The efficacy of the substances in contributing to energy systems was compared before and after a 28-day period of supplementing 6.4g/day of beta-alanine and of 0.3g/kg of body mass of sodium bicarbonate administered 60 minutes before a cycling intermittent exercise, consisting of 4 sets of 1-minute each at 110% of maximum aerobic power with 1-minute intervals between each set and at an even pace. After 10 minutes of passive rest, performance was measured during a time-trial test in which participants were asked the complete 30 kJ of total work as fast as possible. Blood concentration of pH, bicarbonate, base excess, and lactate were measured before, during, and after intermittent and time trial protocols. The contributions of oxidative and anaerobic alactic (ATP-CP) were estimated based on oxygen consumption and the glycolytic system by the delta of lactate concentration. The energy demand of the intermittent exercises mostly consisted of the oxidative system (45-55%), followed by the ATP-CP system (35-40%), lastly glycolytic (8-15%). The sodium bicarbonate supplement elevated (P>0.001) blood concentration of bicarbonate (~6mmol/L) and pH (~0.06) units in the BIC and BA + BIC groups, generated a high concentration of lactate in the first sets, reflecting the increase in glycolytic energy cost in the first set of intermittent exercise, but was only statistically significant in the BIC group (9.9 ± 7.2 KJ vs 18.7 ± 9.4 KJ; pre vs postsupplementation). Supplementation did not have an effect on the time-trial times between groups or supplement periods (BA -0.5%, BIC -1.4%, BA + BIC -4%, PLA 0%). Supplementing with sodium bicarbonate, both alone and together with betaalanine improved blood acid-base control during high-intensity intermittent exercise resulting in high participation of the glycolytic metabolism, however it did not lead to additional performance

The electric power sector is undergoing significant changes with the development of Smart Grid technologies and is rapidly influencing the way we consume energy. Demand Response (DR) is an important element in the emerging smart grid paradigm and is paving way for the more sophisticated implementation of Energy Hub Management Systems (EHMSs). Utilities are looking at Demand Side Management (DSM) and DR services that allow customers to make informed decisions regarding their energy consumption which in return, can help the energy providers to reduce their peak demand and hence enhance grid sustainability. Ice rinks are large commercial buildings which facilitate various activities such as hockey, figure skating, curling, recreational skating, public arenas, auditoriums and coliseums. These have a complex energy system; in which an enormous sheet of ice is maintained at a low temperature while at the same time the spectator stands are heated to ensure comfortable conditions for the spectators. Since indoor ice rinks account for a significant share of the commercial sector and are in operation for more than 8 months a year, their contribution in the total demand cannot be ignored. There is significant scope for energy savings in indoor ice rinks through optimal operation of their climate control systems. In this work, a mathematical model of indoor ice rinks for the implementation of EHMS is developed. The model incorporates weather forecast, electricity price information and end-user preferences as inputs and the objective is to shift the operation of climate control devices to the low electricity price periods, satisfying their operational constraints while having minimum impact on spectator comfort. The inside temperature and humidity dynamics of the spectator area are modeled to reduce total electrical energy costs while capturing the effect of climate control systems including radiant heating system, ventilation system and dehumidification system. Two different pricing schemes, Real Time Pricing (RTP) and Time-of-Use (TOU), are used to assess the model, and the resulting energy costs savings are compared. The expected energy cost savings are evaluated for a 8 month period of operation of the rink incorporating the uncertainties in electricity price, weather conditions and spectator schedules through Monte Carlo simulations. The proposed work can be implemented as a supervisory control in existing climate controllers of indoor ice rinks and would play a significant role in the enforcement of EHMS in Smart Grids.

A tidal current turbine is a device functioning in a manner similar to wind turbine for harnessing energy from tidal currents, a group of which is called a farm. The existing approaches used to predict power from tidal current turbine farms oversimplify the hydrodynamic interactions between turbines, which significantly affects the results. The major focus of this dissertation is to study the relationship between turbine distribution (the relative position of the turbines) and the hydrodynamic interactions between turbines, and its impact on the power from a farm. A new formulation of the discrete vortex method (DVM-UBC) is proposed to describe the behavior of turbines and unsteady flow mathematically, and a numerical model is developed to predict the performance, the unsteady wake and acoustic emission of a stand-alone turbine using DVM-UBC. Good agreement is obtained between the results obtained with DVM-UBC and published numerical and experimental results. Then, another numerical model is developed to predict the performance, wake and acoustic emission of a two-turbine system using DVM-UBC. The results show that the power of a two-turbine system with optimal relative position is about 25% more than two times that of a stand-alone turbine under the same conditions. The torque such a system may fluctuate 50% less than that of a stand-alone turbine. The acoustic emission of such a system may be 35% less than that of a stand-alone turbine. As an extension, a numerical procedure is developed to estimate the efficiency of an N-turbine system by using a linear theory together with the two-turbine system model. By integrating above hydrodynamic models for predicting power and a newly-developed Operation and Maintenance (O&M) model for predicting the cost, a system model is framed to estimate the energy cost using a scenario-based cost-effectiveness analysis. This model can estimate the energy cost more accurately than the previous models because it breaks down turbine’s components and O&M strategies in much greater detail when studying the hydrodynamics and reliability of the turbine. This dissertation provides a design tool for farm planners, and shed light on other disciplines such as environmental sciences and oceanography.

A tidal current turbine is a device functioning in a manner similar to wind turbine for harnessing energy from tidal currents, a group of which is called a farm. The existing approaches used to predict power from tidal current turbine farms oversimplify the hydrodynamic interactions between turbines, which significantly affects the results. The major focus of this dissertation is to study the relationship between turbine distribution (the relative position of the turbines) and the hydrodynamic interactions between turbines, and its impact on the power from a farm. A new formulation of the discrete vortex method (DVM-UBC) is proposed to describe the behavior of turbines and unsteady flow mathematically, and a numerical model is developed to predict the performance, the unsteady wake and acoustic emission of a stand-alone turbine using DVM-UBC. Good agreement is obtained between the results obtained with DVM-UBC and published numerical and experimental results. Then, another numerical model is developed to predict the performance, wake and acoustic emission of a two-turbine system using DVM-UBC. The results show that the power of a two-turbine system with optimal relative position is about 25% more than two times that of a stand-alone turbine under the same conditions. The torque such a system may fluctuate 50% less than that of a stand-alone turbine. The acoustic emission of such a system may be 35% less than that of a stand-alone turbine. As an extension, a numerical procedure is developed to estimate the efficiency of an N-turbine system by using a linear theory together with the two-turbine system model. By integrating above hydrodynamic models for predicting power and a newly-developed Operation and Maintenance (O&M) model for predicting the cost, a system model is framed to estimate the energy cost using a scenario-based cost-effectiveness analysis. This model can estimate the energy cost more accurately than the previous models because it breaks down turbine’s components and O&M strategies in much greater detail when studying the hydrodynamics and reliability of the turbine. This dissertation provides a design tool for farm planners, and shed light on other disciplines such as environmental sciences and oceanography.

The electric power sector is undergoing significant changes with the development of Smart Grid technologies and is rapidly influencing the way we consume energy. Demand Response (DR) is an important element in the emerging smart grid paradigm and is paving way for the more sophisticated implementation of Energy Hub Management Systems (EHMSs). Utilities are looking at Demand Side Management (DSM) and DR services that allow customers to make informed decisions regarding their energy consumption which in return, can help the energy providers to reduce their peak demand and hence enhance grid sustainability. Ice rinks are large commercial buildings which facilitate various activities such as hockey, figure skating, curling, recreational skating, public arenas, auditoriums and coliseums. These have a complex energy system; in which an enormous sheet of ice is maintained at a low temperature while at the same time the spectator stands are heated to ensure comfortable conditions for the spectators. Since indoor ice rinks account for a significant share of the commercial sector and are in operation for more than 8 months a year, their contribution in the total demand cannot be ignored. There is significant scope for energy savings in indoor ice rinks through optimal operation of their climate control systems. In this work, a mathematical model of indoor ice rinks for the implementation of EHMS is developed. The model incorporates weather forecast, electricity price information and end-user preferences as inputs and the objective is to shift the operation of climate control devices to the low electricity price periods, satisfying their operational constraints while having minimum impact on spectator comfort. The inside temperature and humidity dynamics of the spectator area are modeled to reduce total electrical energy costs while capturing the effect of climate control systems including radiant heating system, ventilation system and dehumidification system. Two different pricing schemes, Real Time Pricing (RTP) and Time-of-Use (TOU), are used to assess the model, and the resulting energy costs savings are compared. The expected energy cost savings are evaluated for a 8 month period of operation of the rink incorporating the uncertainties in electricity price, weather conditions and spectator schedules through Monte Carlo simulations. The proposed work can be implemented as a supervisory control in existing climate controllers of indoor ice rinks and would play a significant role in the enforcement of EHMS in Smart Grids.

Running economy is well established as a primary determinant of endurance running performance. However, there is a lack of clarity about the preferred measurement of running economy, its primary limiting factors and the most robust methods enhance running economy in highly trained athletes. Therefore, this thesis investigated the running economy of highly trained runners, exploring the reliability and validity of measures of running economy to deduce its most appropriate quantification, the application of innovative methods to enhance our understanding of an athlete s running economy, and a novel training method to enhance running economy. Chapter 3 revealed that energy cost and oxygen cost were shown to provide similarly high levels of reliability (typical error of measurement ~3%) for highly trained endurance runners when assessed using a short-duration incremental submaximal exercise protocol. In chapter 4, the analysis of a large cohort of highly trained endurance runners revealed that energy cost increased in a stepwise manner with increments in running speed (P<0.001), however oxygen cost remained consistent (P=0.54) across running speed; indicating that oxygen cost might not be an appropriate measure of running economy. Chapter 5 demonstrated that the inter-individual variation in the magnitude of changes in energy cost between different gradients (i.e. from flat running to uphill/downhill running) in highly trained runners was low. However, a disparity between the energy saving of running on a -5% gradient (-17%) and the additional energy cost of running on a +5% gradient (+32%) was evident. The cross-sectional and longitudinal analysis of a large cohort of highly trained runners in chapter 6 revealed a small (r=0.25) and moderate (r=0.35) association between energy cost and maximal oxygen uptake, respectively. Finally, chapter 7 demonstrated that eight weeks of supplementary downhill run training at vLTP in existing training programmes does not enhance running economy in already well trained runners (1.22 vs 1.20 kcal kg-1 km-1; P=0.41), despite a significant increase (+2.4%) in the velocity at lactate turnpoint. In conclusion, this thesis demonstrates that energy cost, expressed as kcal kg-1 km-1, provides a reliable and valid method to quantify running economy in trained distance runners. However, further investigation is required to identify robust training methods to enhance running economy in this already highly trained population.