No description available.

Low back pain (LBP) remains the most prevalent and costly work-related disability worldwide and is directly associated with "physical" risk factors prevalent in manual material handling (MMH) tasks. Back-support exoskeletons (BSEs) are a promising ergonomic intervention to mitigate LBP risk, by reducing muscular exertion and spine loading. The purpose of this work was to help better understand both the "intended" and "unintended" consequences of BSE use on physical risk factors for LBP, as an essential prerequisite for the safe and effective implementation of this technology in actual workplaces. The first study assessed the effects of using two BSEs on objective and subjective responses during repetitive lifting involving symmetric and asymmetric postures. Wearing both BSEs significantly reduced peak levels of trunk extensor muscle activity and reduced energy expenditure. Such reductions, though, were more pronounced in the symmetric conditions and differed between the two BSEs tested. The second study quantified the assistive torque profiles of two passive BSEs using a computerized dynamometer, with both human subjects and a mannequin. Clear differences in torque magnitudes were evident between the BSEs, though both generated more assistive torques during flexion than extension. The third study estimated the effects of BSE use on lumbosacral compressive and shear forces during repetitive lifting using an optimization-based model. Using both BSEs reduced peak compression and anteroposterior shear forces, but these effects differed between tasks and BSE designs. Reductions in composite measures of trunk muscle activity did not correspond consistently with changes in spine forces when using a BSE. The fourth study quantified the effects of two passive BSEs on trunk stability and movement coordination during repetitive lifting. Some adverse effects on stability were evident for pelvis and thorax movements and coupling of these body segments, suggesting that caution is needed in selecting a BSE for a given MMH task. Overall, we found that the efficacy of BSEs is design- and task-specific. Important safety features of the exoskeletons were also identified, providing insights on their performance boundaries. Overall, the BSEs tested were more effective and safer in tasks closer to the mid-sagittal plane and with moderate degrees of trunk flexion. / Doctor of Philosophy / Low back pain (LBP) remains the most prevalent and costly work-related disability worldwide, and the risk of LBP is related to "physical" risk factors common in manual material handling (MMH) tasks. Back-support exoskeletons (BSEs) are a new ergonomic intervention that may reduce the risk of occupational LBP, by reducing muscular efforts and loads on the spine. For the safe use of BSEs, though, it is critical to better understand both the "intended" and "unintended" consequences of this emerging technology. In this dissertation, such consequences of BSE use were evaluated in the context of repetitive lifting tasks. The first study assessed the efficacy of two BSEs in terms of physical demands during repetitive lifting tasks involving a range of torso bending and twisting. Wearing both BSEs reduced the physical demands on back muscles and decreased energy consumption. Larger reductions, though, were observed in forward bending and such reductions differed between the two BSEs tested. The second study measured the amount of support provided by two BSEs using a new measurement method, which was examined for both human subjects and a mannequin. Clear differences in the BSE support were evident between the BSEs, and both devices generated more support during torso forward bending than returning upright. The third study estimated the effects of BSE use on low back loadings during repetitive lifting using a computational model. Using both BSEs reduced loads on the low back region, though such reductions were task-specific and depended on the BSE design. The fourth study quantified the effects of the BSE use on torso stability and movement patterns during repetitive lifting. Some adverse effects on stability were evident for lower and upper torso, suggesting that caution is needed in selecting a BSE for a given MMH task. Findings from this work show the potential benefits of BSEs for use in MMH tasks, yet such benefits can depend on the BSE design and the MMH task they are used for. Further, BSE use can lead to adverse effects, especially with tasks involving extreme working postures.

Consistently, reports in the literature have identified that a sedentary lifestyle contributes to the progression of a range of chronic degenerative diseases. The measurement of energy expenditure and physical activity pattern in children is a challenge for all professionals interested in paediatric health and from a broader perspective, the public health fraternity charged with considering longer term health consequences of physical inactivity. The primary objective of this thesis was to identify a suitable indirect and objective measurement technique for the assessment of energy expenditure and physical activity pattern in children. The ideal characteristics of such a technique are that it should be reproducible and have been validated against a criterion reference method. To achieve this goal, a series of methodological studies were undertaken (Chapters II and III). This work was essential to increase accuracy during the individualised laboratory calibration process and further minimise prediction errors when analysing data from 7 days of monitoring under free-living conditions in the second part of the study (Chapters IV and V). In the first study to verify the combined effect of body position, apparatus and distraction on children's resting metabolic rate (RMR), experiments were carried out on 14 children aged 8-12 (mean age = 10.1 years ± 1.4). Each participant underwent 2 test sessions, one week apart under three different situations: a) using mouthpiece and nose-clip (MN) or facemask (FM); b) sitting (SEAT) or lying (LY) and c) TV viewing (TV) or no TV viewing. In the first session, following 20 min rest and watching TV, the following protocol was used: LY: 20 min - stabilisation; 10 min using MN and 10 min using FM. Body position was then changed to seated: 20 min stabilisation; 10 min using FM; 10 min using MN. In the second session, FM and MN order was changed and participants did not watch TV. Data were analysed according to the eight combinations among the three studied parameters. Repeated measures ANOVA indicated statistically significant differences for &VO2 (p=0.01) and RMR (p=0.02), with TVMNSEAT showing higher values than TVFMLY. Bland-Altman analysis showed a bias for &VO2, &VCO2, RQ and RMR between TVFMLY and TVMNSEAT of -17.8±14.5 ml.min-1, -8.8±14.5 ml. min-1, 0.03±0.05 and -115.2±101.9 kcal.d-1, respectively. There were no differences in RMR measurements due to body position and apparatus when each variable was isolated. Analyses of distraction in three of four combinations indicated no difference between TV and no TV. In summary, different parameter combinations can result in increased bias and variability and thereby reported differences among children's RMR measurement. The second study dealt with treadmill adaptation and determination of self-selected (SS) walking speed. Assessment of individual and group differences in metabolic energy expenditure using oxygen uptake requires that individuals are comfortable with, and can accommodate to, the equipment being utilised. In this study, a detailed proposal for an adaptation protocol based on the SS was developed. Experiments were carried out on 27 children aged 8-12 (mean age = 10.3±1.2 yr). Results from three treadmill tests following the adaptation protocol showed similar results for step length with no significant differences among tests and lower and no statistically significant variability within- and between-days. Additionally, no statistically significant differences between SS determined over-ground and on a treadmill were verified. These results suggest that SS speed determined over-ground is reproducible on a treadmill and the 10 min familiarisation protocol based on this speed provided sufficient exposure to achieve accommodation to the treadmill. The purpose of the third study was to verify within- and between-day repeatability and variability in children's oxygen uptake ( &VO2), gross economy (GE) [ &VO2 divided by speed] and heart rate (HR) during treadmill walking based on SS. 14 children (mean age = 10.2±1.4 yr) undertook 3 testing sessions over 2 days in which four walking speeds, including SS, were tested. Within- and between-day repeatability was assessed using the Bland and Altman method and coefficients of variability (CV) were determined for each child across exercise bouts and averaged to obtain a mean group CV value for &VO2, GE and HR per speed. Repeated measures ANOVA showed no statistically significant differences in within- or between-day CV for &VO2, GE or HR at any speed. Repeatability within and between-day for &VO2, GE and HR for all speeds was verified. These results suggest that submaximal &V O2 during treadmill walking is stable and reproducible at a range of speeds based on children's SS. In the fourth study, the objective was to establish the effect of walking speed on substrate oxidation during a treadmill protocol based on SS. Experiments were carried out on 12 girls aged 8-12 (mean age = 9.9±1.4 yr). Each participant underwent 2 test sessions, one week apart. Workloads on the treadmill included 2 speeds slower than SS (1.6 [V1] and 0.8 km.h-1 [V2] slower than SS), SS (V3), and a speed 0.8 km.h-1 faster than SS (V4). Indirect calorimetry from respired gas measurements enabled total fat (FO) and carbohydrate (CHO) oxidation rates to be calculated according to the non-protein respiratory quotient (Peronnet and Massicote, 1991) and percentage of CHO and FO calculations using equations from McGilvery and Goldstein (1983). Repeated measures ANOVA followed by a Tukey Post Hoc test (p< 0.05) was used to verify differences in CHO and FO rates among speeds. Paired T-test was used to verify differences in CHO and FO rates between tests per velocity. The reliability between-day was assessed using intraclass correlation coefficient (ICC). Results showed significant differences for CHO among all speeds, as well as significant differences for FO between V1 and V2 against V3 and V4 in both tests. Analyses between trials per velocity showed no significant substrate use differences as well as acceptable reliability. At the self-selected speed (V3) there was an accentuation in FO reduction as well as an increase in CHO oxidation. The purpose of the fifth study was to determine whether there were differences in substrate oxidation between girls (G) and women (W) during a treadmill protocol based on SS. Experiments were carried out on 12 G aged 8-12 (mean age = 9.9±1.4 yr) and 12 W aged 25-38 (mean age = 32.3±3.8 yr). The treadmill protocol included 6 min workloads followed by 5 min rest periods. Workloads included 2 speeds slower than SS (1.6 (V1) and 0.8 km.h-1 (V2) slower than SS), SS (V3), and a speed 0.8 km.h-1 faster than SS (V4). Total fat and carbohydrate (CHO) oxidation rates were calculated from indirect calorimetry according to the non-protein respiratory quotient. Repeated measures ANOVA followed by a Tukey Post Hoc test was used to verify intra-test differences in CHO and fat oxidation rates among speeds. Intergroup differences were analysed using paired T-test. Fat utilisation in W achieved a plateau at a relative velocity 0.8 km.h-1 slower than SS, but for G, fat utilisation increased until SS, and then stabilised upon reaching the higher velocity. CHO oxidation curves rose abruptly above V2 for W, while for G the acute increase occurred after SS (V3). Collectively, these results indicate that as walking intensity increases G are able to meet the energy demands of the work by increasing fat oxidation together with the increased CHO oxidation up to SS. In contrast for W, increasing CHO oxidation is associated with an early decrease in fat utilisation at a velocity slower than the self-selected speed. The sixth study dealt with validation of indirect techniques for the measurement of energy expenditure in free-living conditions against the DLW technique. Experiments were carried out on 19 children aged 8-12 (mean age = 10.3±1.0 yr). To indirectly predict energy expenditure 12 different procedures were used. Only one procedure, combining activity and heart rate (AHbranched), was based on a group equation, the others were based on individualised regression. Three of the individually-based techniques were able to accurately predict energy expenditure in free-living conditions. These tecniques were HRPAnetRMR using HRnet [HR exercise minus sleep HR (SHR)] against PAnet (measured PA exercise minus measured RMR) and upper and lower body equations corrected by RMR; HRPAnet4act using the same procedure but corrected by the mean resting &VO2 for 4 resting activities [(4act) = supine watching TV, sitting watching TV, sitting playing computer games and standing], and HRPALBnet4act using only lower body activities and corrected by 4act. HRPAnetRMR was only slightly more accurate than HRPAnet4act and HRPALBnet4act, but this technique is only adjusted by RMR whereas the other two are heavily dependent on more complex laboratory calibration. Bland and Altman (1986) analyses showed no significant differences between AHbranched predicted and measured TEE using the DLW technique. A SEE of 79 kcal.d-1 and a mean difference of 72 kcal.d-1, with a 95% CI ranging from -238 to 93.9 kcal.d-1 was found. In addition, no significant differences between predicted HRPAnetRMR and measured TEE using DLW were found, showing an SEE of 99 kcal.d-1 and a mean difference of -67 kcal.d-1, and a 95% CI ranging from -276.6 to 141.9 kcal.d-1. AHbranched and HRPAnetRMR were both valid and similarly suitable for the prediction of energy expenditure in children under free-living conditions. Significant associations between DLWAEE and the after-school time window indicated that this time window as an important discretionary period representative of children physical activity. However, the duration of the after-school time windows should be more carefully considered. Accelerometer data showed a better association between the largest after-school time window (3.5 hr) and measured TEE. The final study, completed with 19 children aged 8-12 (10.3±1.0 yr) highlighted, under laboratory conditions across a range of walking and running speeds, the inadequacy of the use of the standard MET in children. This traditional approach overestimates energy expenditure with an increased difference linearly related to speed increments. Minute-by-minute analyses of 7 days of free-living monitoring showed an average overestimation of 64 minutes per day for moderate-to-vigorousphysical- activity (MVPA) using the standard MET compared with the individually measured MET. For all intensities, these differences were statistically significant (p< 0.001). The second part of this study showed a variability of 20% in the average time spent at MVPA when comparing HR I 140 bpm and HR > 50%P &VO2 (P &VO2 = the highest &VO2 observed during an exercise test to exhaustion). Results of the current study compared to observations in the literature showed that HR I 140 bpm consistently estimates lower MVPA time than HR > 50%P &VO2. When these two PA indices were compared with individual and standard MET measured minute-byminute, statistically significant differences were verified among all of them at MPA, but no differences were verified at VPA, except between individual and standard METs. However, whether each one of the PA indices used are under- or overestimating time at MVPA is still debatable due to the lack of a gold standard. Finally, each index used in this study classified different numbers of participants as achieving the PA target of 60 min.d-1. The wide variability between indices when attempting to classify children who are achieving the recommended target is cause for great concern because habitually these indices are utilised as screening tools in paediatric and public health settings and used to guide behavioural interventions.

Le risque cardiométabolique (RCM) représente l’ensemble de tous les facteurs de risque pour les maladies cardiovasculaires et le diabète de type 2, incluant les facteurs de risque traditionnels et ceux émergents. Les évidences indiquent que la résistance à l’insuline, l’inflammation et le stress oxydant jouent un rôle clé dans le RCM, bien que l’acteur initiateur des altérations métaboliques caractéristiques du RCM reste encore à définir. Les femmes post-ménopausées constituent un sous-groupe important de la population puisque le risque de complications cardiométaboliques augmente après la ménopause. Les facteurs de RCM peuvent être modulés par l’alimentation, l’activité physique et la perte de poids. Alors que l’étude de nutriments / aliments spécifiques a permis de mieux comprendre l’implication de l’alimentation dans le RCM, celle de la qualité de l’alimentation est prometteuse. L’activité physique a des effets bénéfiques sur le RCM bien démontrés chez des personnes actives. Cependant, la relation entre la dépense énergétique et le RCM chez des individus sédentaires a été moins investiguée. De même, peu ou pas de données existent quant à une interaction synergique possible entre l’alimentation et l’activité physique sur le RCM. L’objectif de la présente thèse est d’investiguer les relations entre l’alimentation, l’activité physique, le stress oxydant et le RCM chez des femmes post-ménopausées en surpoids ou obèses, sédentaires et sans autres complications métaboliques. Les résultats montrent que d’une part, chez ces femmes sédentaires, une dépense énergétique active (DÉAP) élevée est associée à un meilleur profil inflammatoire, indépendamment de l’adiposité. D’autre part, il existe une relation synergique entre la qualité alimentaire et la DÉAP associée à un meilleur RCM. Une qualité alimentaire élevée combinée à une DÉAP élevée est associée à un meilleur profil lipidique et lipoprotéique et à une inflammation sub-clinique moindre, indépendamment de l’adiposité. Par ailleurs, dans une étude pilote, seuls des effets indépendants des changements de la qualité alimentaire et de la DÉAP sur les changements dans les facteurs de RCM ont été observés suite à cette diète hypocalorique de 6 mois, indépendamment du changement de l’adiposité encouru. En effet, au-delà de la réduction de l’adiposité et de l’amélioration du profil lipoprotéique induites par l’intervention, l’amélioration de la qualité alimentaire et de la DÉAP est associée, indépendamment l’une de l’autre, à une meilleure pression artérielle et un meilleur profil lipidique. Par ailleurs, une modification du système glutathion, un des systèmes antioxydants les plus communs de l’organisme, est associée à un RCM élevé. Une activité élevée de la glutathion peroxydase est associée à une résistance à l’insuline et à une épaisseur plus importante de l’intima-media de la carotide. Ces relations pourraient être médiées par un stress réducteur. En conclusion, l’adoption d’une saine alimentation et la pratique d’activités physiques doivent être encouragées dans les interventions visant à contrer l’obésité et ses complications, même en absence d’un changement d’adiposité. D’autre part, l’activité de la glutathion peroxydase pourrait être un paramètre impliqué dans le développement de désordres cardiométaboliques sub-cliniques et asymptomatiques chez des femmes obèses. D’autres investigations sont requises pour confirmer ces observations et élucider les mécanismes d’action impliqués. / The cardiometabolic risk represents all risk factors for cardiovascular diseases and type 2 diabetes, including the traditional and the emerging risk factors. Accumulating evidences indicate that insulin resistance, inflammation and oxidative stress are key players in the cardiometabolic risk, although the main cause initiating the metabolic alterations associated with the cardiometabolic risk has to be identified. Postmenopausal women are an important sub-group of the general population because the risk of developing cardiometabolic complications increases after menopause. The cardiometabolic risk factors can be modulated by dietary intake, physical activity and weight loss. Despite the fact that the study of specific nutrients or foods provided a better understanding of the implication of nutrition in the cardiometabolic risk, the relationship between diet quality and cardiometabolic risk has been less studied. Beneficial effects of physical activity on the cardiometabolic risk have been demonstrated in physically active individuals. However, the relationship between energy expenditure and the cardiometabolic risk in sedentary individuals has been less investigated. Similarly, it is unknown whether dietary intake interacts with physical activity in order to have greater beneficial effects on the cardiometabolic risk. The objective of this thesis is to determine the relationships between diet quality, physical activity and oxidative stress on the cardiometabolic risk in sedentary postmenopausal overweight and obese women without cardiometabolic complications. The results showed that, in these sedentary women, physical activity energy expenditure is associated with reduced inflammation, independently of adiposity. Moreover, there is a synergistic relationship between quality and physical activity energy expenditure (PAEE) which is associated with a reduced cardiometabolic risk compared to their separate effects. Indeed, high diet quality combined to high PAEE levels is associated with a better lipid and lipoprotein profile and a lower inflammatory status, independently of adiposity. However, in a pilot study, only independent effects of changes in diet quality and PAEE on the changes in cardiometabolic risk factors was observed following a 6-month hypocaloric diet. Indeed, beyond the reduction of adiposity and improvement of the lipoprotein profile induced by this diet, improved diet quality and increased PAEE are associated with beneficial changes in blood pressure and lipid profile. On the other hand, modification in the glutathione system, which is one of the most common antioxidant systems in the body, is associated with a higher cardiometabolic risk. Greater glutathione peroxidase activity is associated with insulin resistance and greater intima-media thickness of blood vessels. These relationships may be mediated through a reductive stress. In conclusion, a healthy diet and physical activity should be emphasized in interventions aimed to reduce obesity and its related complications, even in absence of change in adiposity. Moreover, glutathione peroxidase activity may be a parameter contributing to the development of sub-clinical but clinically relevant asymptomatic cardiometabolic abnormalities in obese women. Further investigations are needed to confirm these results and to elucidate the underlying mechanisms.

Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Biological and Medical Sciences Student: Terezie Poláková Supervisor of master thesis: PharmDr. Miroslav Kovařík, Ph.D. Title of master thesis: Assessment of energy metabolism in patients with chronic obstructive pulmonary disease. Chronic obstructive pulmonary disease (COPD) is the name for lung disease with systemic consequences. Besides the respiratory symptoms there are also described changes in body metabolism, which could lead to the development of serious metabolic syndrome called cachexia. The main aim of this study was to compare the resting energy expenditure (REE) and nutrition substrate utilization in 12 patients with advanced form of COPD from the Czech Multicentre Research Database of COPD (5 females and 7 males, mean age 68 ± 6 years) and in 9 patients of control group without respiratory impairment (5 females and 4 males, 62 ± 4 years). Assessment of body metabolism was determined by method of indirect calorimetry. Measured REE was then compared with prediction based on Harris-Benedict equation. The utilization of main nutrition substrates was determined from the respiratory quotient and urea nitrogen loss in urine. We found that measured REE in COPD patients was about 20 % higher than in control group....

Title: Functional Profile of Performance Billiard Players Objectives: The main aim of thesis was to find out maximal functional characteristics and body composition of performance billiard players by using laboratory testing. Next step was to define load intensity during simulated match. Methods: There were used biomedical measurements as a body measuring, bioelectrical impedance, laboratory spiroergometric measuring by maximal stress testing. Field spiroergometric measuring was provide during simulated match in pool hall. To find the role of physical fitness in performance billiard were used half structured interview with open questions and online survey. Results: The findings show that tested billiard players achieve levels of physical fitness from average to very good values. But some of them are classified as overweight and obese. Long-time playing billiard does not have any important influence on asymetric composition of muscle mass of upper limbs. During playing billiard an oxygen consumption didn't get over 30% of VO2max and values of heart rate were between 39 to 59% HRmax. During playing billiard an energy expenditure grows from 222 to 330% of BM. Billiard energetic demands of tested players are moving between 14,6 kJ to 29,3 kJ. Another result of thesis is a statement about the role of...

Title: Appropriateness of choice to walk or run, depending on the speed of a quick relocation with load carriage Objectives: Comparison of physiological response of organism during the walk and run at speed 6 - 7,4 km.h-1 with carried load 15 kg with follow-up determination of critical speed in connection with economy of these activities where there were discovered sizes of correlation with proportional representation of fat free mass and working length of lower limb. Methods: The method applied in this research was the quantitative research based on intra-individual and inter-individual comparative analysis. Results: Based on the measured data it has been found out that there is a critical speed at 7,43 km.h-1 (±0,53), with respect to economy of walk compared to run with 15 kg load. The average heart rate during the critical speed was 129 BPM (±9,67). The average energy expenditure per minute during the critical speed was 11,9 kcal (±2,04). In addition there were discovered sizes of correlation between critical speed and the working length of lower limb where rP = 0,9203 was statiscitally significant. (α = 0,05) and between critical speed and proportional representation of fat free mass, where rP = 0,1529 was not found to be statistically significant (α = 0,05). Keywords: quick relocation, load...

Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Biological and Medical Sciences Student: Magdaléna Doleželová Supervisor of master thesis: PharmDr. Miroslav Kovařík, Ph.D. Title of master thesis: Body composition parameters in dependence on the metabolism degrese in patiens with COPD Chronic Obstructive Pulmonary Disease (COPD) is a very serious illness characterized by incompletely reversible airflow obstruction and lung emphysema. Contributes to its overall severity are extrapulmonary manifestations, especially cachexia and loss of lean tissue mass. Chronic inflammation of the respiratory airways and increased respiratory effort cause the hypermetabolic state to some patients with COPD. This thesis investigates the impact of increased metabolism on body composition in patients with COPD. Our study included 50 COPD patients (38 men, 12 women) who were examined by bioelectrical impedance. In this study, we compared the parameters of body composition of men with resting energy expenditure REE > 130% (hereinafter Men over 130%) (n = 9) and the group of men with REE < 130 % (hereinafter Men below 130 %) (n = 29). In the group of Men over 130 % we found a lower average value of body weight by 18 % compared to Men below 130 %. Total body and intracellular water were 12 %...

Uma sessão de exercício aeróbio provoca queda da pressão arterial (PA) e aumento da freqüência cardíaca (FC) pós-exercício. Diversos fatores, como a massa muscular, a intensidade e o gasto energético total do exercício podem influenciar esta resposta. Este estudo verificou as respostas pós-exercício da PA, da FC e de seus mecanismos, avaliando a influência dos fatores citados. Vinte e quatro jovens submeteram-se a quatro sessões: controle(C); exercício com um membro inferior (mmii) em 50% do VO2pico(E1); exercício com dois mmii em 50% do VO2pico (E2); e exercício com dois mmii com a mesma potência de E1(E2/1). As PA sistólica (PAS), média (PAM) e diastólica (PAD), o débito cardíaco (DC), a resistência vascular periférica (RVP), o volume sistólico (VS), a FC e a modulação autonômica cardíaca foram medidos. Após o exercício, a PAS e o DC diminuíram e a RVP aumentou em E2. A PAD e PAM não se alteraram. A FC aumentou e o VS e o componente de alta freqüência da variabilidade da FC diminuíram em E1 e E2 (maior em E2). Concluindo: o exercício aeróbio promove hipotensão pós-exercício, devido à queda do DC pela redução do VS. O gasto energético total do exercício é o principal determinante desta resposta. A FC permanece elevada pós-exercício devido ao retardo da reativação vagal. A intensidade e o gasto energético do exercício são os principais determinantes desta resposta / A single bout of aerobic exercise reduces blood pressure (BP) and increases heart rate (HR) during the recovery period. Many factors, such as exercise intensity, muscle mass and total energy expenditure might influence this response. This study verified post-exercise responses of BP, HR and their mechanisms, evaluating the influence of previous factors. Twenty-four subjects underwent four sessions: control (C); exercise with one leg at 50% of VO2peak (E1); exercise with two legs at 50% of VO2peak (E2); and exercise with two legs and the same workload employed in E1 (E2/1). Systolic, mean, and diastolic BPs (SBP, MBP, DBP), systemic vascular resistance (SVR), cardiac output (CO), stroke volume (SV), HR, and cardiac autonomic modulations were measured before and after interventions. After exercise, SBP and CO decreased, while SVR increased in E2. DBP and MBP did not change. HR increased, while SV and the high frequency band of HR variability decreased in E1 and E2 (more in E2). In conclusion: aerobic exercise produced post-exercise hypotension by a decrease in CO, via a decrease in SV. This response is determined by the exercise total energy expenditure. HR is elevated after exercise due to a delay in the restoration of vagal activity to the heart. Exercise intensity and total energy expenditure influence this response. Key-words: aerobic exercise, muscle mass, total energy expenditure, relative intensity, blood pressure, heart rate, autonomic modulation

O exercício físico e a alimentação adequada apresentam estreita relação. O triatlon é uma modalidade que apresenta elevada demanda energética por associar três diferentes tipos de exercício. Objetivos -Verificar a adequação do valor energético total em relação ao dispêndio energético diário, a adequação de macronutrientes da alimentação em relação à recomendação e a contribuição de complemento nutricional. Métodos - Foi mensurado peso corporal de triatletas adultos, de ambos os sexos, a fim de predizer o dispêndio energético diário. Para análise da alimentação foi utilizado diário alimentar de três dias e, para obtenção do dispêndio energético diário, optou-se pelo diário de atividade física de três dias, proposto por Bouchard et al. (1983). Análise estatística - Para análise dos dados utilizou-se estatística descritiva com medidas de tendência central (média e mediana) e dispersão (desvio-padrão, valores mínimos e máximos), teste de Wilcoxon e t-Student. Os resultados foram analisados ao nível de 5% de significância. Resultados - Os 22 triatletas avaliados apresentam idade entre 20 e 45 anos (33±6 anos). O complemento nutricional foi utilizado por 95,4% dos atletas. Dentre os complementos, 76,2% eram compostos à base de carboidrato, 71,4% bebida esportiva, 33,3% compostos protéicos, 9,5% vitamínico-minerais e lipídicos. A alimentação forneceu, em média, 2.800 kcal/dia e, a alimentação associada ao complemento nutricional, representou 3.000 kcal/dia. A maioria dos atletas (90,9%) consumiu proteína em quantidades elevadas, 72,7% ingeriram carboidratos em quantidades inferiores ao recomendado e, 57,7% ingeriram lipídios adequadamente, considerando-se somente a alimentação. Com complemento nutricional, observa-se o mesmo desequilíbrio de macronutrientes. O dispêndio energético diário médio foi de 3.490 kcal, sendo que 83,4% dos atletas apresentam dispêndio maior do que a ingestão alimentar, na ausência de complemento. Conclusões - A alimentação destes triatletas é insuficiente para atender o dispêndio energético diário; o consumo de proteína é superior ao recomendado; o consumo de carboidratos é inferior ao recomendado; o consumo de lipídios é adequado; o uso de complemento nutricional é pratica habitual por triatletas e não contribui de forma estatisticamente significativa para atingir às necessidades energéticas e recomendações de carboidratos (p>0,05), embora contribua para o aumento das proteínas e, alteração do percentual de lipídios de forma significativa (p&#8804;0,05). / Physical exercise and proper diet are closely related, since what is eaten influences physical performance. Triathlon has a high energy demand as it is associated to three types of exercise. Objectives - To find the suitability of the energy intake in relation to the daily energy expenditure, suitability of macronutrients in food in relation to the recommendation of and the contribution of nutritional supplements. Methods - The body weight of adult triathletes of both sexes was measured in order to forecast the daily energy expenditure. A daily food intake of a three day period was used for diet analysis. The daily physical activity of a three day period was used to obtain the daily energy expenditure as proposed by Bouchard et al. (1983). Statistical Analysis - For the analysis of data, descriptive statistics was used with center tending measurements (average and median) and dispersion (standard deviation, minimum and maximum values), Wilcoxon and t-Student tests. The results were analyzed at the level of 5% significance. Results - The 22 triathletes were aged between 20 and 45 (age 33±6). Nutritional supplements were used by 95.4% of the athletes, of which: 76.2% of carbohydrates base compound, 71.4% sport drinks, 33.3% protein compound, 9,5% vitamin-minerals and lipids. The diet supplied on average 2.800 kcal/day and, with the nutritional supplements, 3.000 kcal/day. Of all the triathletes, 90,9% consumed high quantities of protein, 72,7% had intake of carbohydrates below the recommended level and 57,7% ingested lipids in adequate quantities, taking only food into account. With nutritional supplements, the same unbalance of macronutrients was observed. The average daily energy expenditure was 3.490 kcal, with 83,4% of the athletes showing a higher consumption than food intake in the absence of the supplements. Conclusions - The diet of these triathletes is insufficient to meet the daily energy expenditure; consumption of protein is higher than the recommended quantity; consumption of carbohydrates is lower than the recommended quantity; consumption of lipids is adequate; use of nutritional supplements is habitual to the triathletes and do not contribute in a statistically significant manner to achieve the energy requirements and carbohydrates recommendation (p>0,05), although they contribute to an increase of proteins and a change of the lipid percentage (p&#8804;0,05).