Bei 22 Patienten mit Leberzirrhose wurde prospektiv der Ernährungszustand mit seinen Komponenten Energieverbrauch, Nahrungsaufnahme und Körperzusammensetzung sowohl vor Anlage eines TIPS, als auch 1, 6 und 12 Monate nach TIPS-Implantation untersucht und in Beziehung zu Daten gesunder Probanden gesetzt. Im Vergleich zu gesunden Kontrollpersonen waren bei Patienten vor TIPS-Anlage Körpergewicht und body-mass-index nicht vermindert, während Muskel- und Körperzellmasse (BCM) reduziert waren. Im Grundumsatz (REE) bestand kein Unterschied zu Kontrollen, wenn der gesamte Grundumsatz betrachtet wird. Dagegen war der spezifische, auf die Körperzellmasse bezogene Grundumsatz (REE/BCM) bei Patienten signifikant erhöht. Patienten wiesen also gegenüber Kontrollen einen hypermetabolen Status auf. Die Substratoxidation der Patienten war durch eine bevorzugte Verwendung von Lipiden gekennzeichnet. Nach TIPS-Anlage nahmen Körpergewicht und BMI der Patienten zu aufgrund einer Verbesserung in der Körperzusammensetzung mit signifikantem Anstieg von Muskelmasse, Körperzellmasse und dem Quotienten von Körperzellmasse und Körpermasse. Darüberhinaus war eine signifikante Abnahme der Aszitesmenge zu verzeichnen. Die Fettmasse blieb trotz Zunahme der Körpermasse unverändert. Entsprechend der Zunahme der Körpermasse stieg der Grundumsatz nach TIPS-Anlage signifikant an, die Betrachtung des spezifischen Energieumsatzes zeigte jedoch eine abnehmende Tendenz im Sinne einer Normalisierung des bei Zirrhosepatienten gegenüber Kontrollen erhöhten Energieumsatzes. Dieser Abnahme des spezifischen Energieverbrauchs stand eine zunehmende Nährstoffaufnahme gegenüber, so daß diese Verbesserung der Energiebilanz als eine der Ursachen für die Verbesserung des Ernährungzustandes zu sehen ist. Unbeeinflußt von der TIPS-Anlage blieb die Bevorzugung von Fett als oxidativem Substrat. Bezüglich der Organfunktionen war nach TIPS-Anlage eine partielle Verminderung der hepatischen Syntheseleistung (Quick, nicht aber Albumin) und eine signifikante Verbesserung der Nierenfunktion und psychometrisch gemessenen hirnorganischen Leistungsfähigkeit zu beobachten. Die Anlage und Funktionserhaltung eines TIPS war bei Patienten mit Leberzirrhose mit einer bedeutsamen Verbesserung des Ernährungszustandes und insbesondere des prognostisch relevanten Kompartiments Körperzellmasse und Muskelmasse verbunden. Bei unveränderten Ernährungsempfehlungen waren die Patienten in höherem Maße in der Lage, diese Empfehlungen zu realisieren und insbesondere eine höhere Eiweißmenge ohne Verschlechterung der Enzephalopathie zuzuführen. Welchen Einfluß die einzelnen Faktoren wie verminderte Aszitesmenge, Verbesserung der intestinalen Absorption oder Vermeidung erneuter kataboler Situationen (gastrointestinale Blutungen, Parazentese und Endotoxinämie durch Reduktion der portalen Hypertension) an diesem Ergebnis haben, muß durch weitere Untersuchungen geklärt werden. / 22 patients with liver cirrhosis were examined prospectively regarding their nutritional state and its components energy expenditure, energy intake and body composition before and 1, 6 and 12 months after implantation of a transjugular intrahepatic portosystemic stent - shunt (TIPS). These data were compared to those corresponding of a group of healthy control subjects. Compared to these healthy individuals body weigth and body mass index (BMI) of the patients were not reduced while muscle mass and body cell mass (BCM) were impaired before TIPS-implantation. There was no difference in resting energy expenditure (REE) between both groups. The ratio REE/BCM is called specific resting energy expenditure. This ratio was found to be increased in the patient group which means that patients were hypermetabolic when compared to controls. Lipids turned out to be the prefered fuel in patients. After TIPS-insertion body weight and BMI increased in patients because muscle mass, BCM and BCM/body weight all increased significantly in the patient group. Meanwhile the amount of ascites was reduced significantly. Fat mass remained stable after TIPS. Because of this increase of body weight energy expenditure had to increase, too. On the contrary, the specific REE showed a decrease which means normalization of the pathological high results of this parameter. A decrease in specific REE and an increase in energiy intake lead to an improvement of energy balance. This is probably one min cause of the improvement in the nutritional state of the patients after TIPS. After TIPS lipids remained to be the main source of substrate for oxidation. Partly, the synthetical function of the liver was impaired after TIPS (thromboplastin time, but not Albumin) while renal function and mental performance measured by psychometric tests improved significantly. The implantation of TIPS and surveillance of its function in patients with liver cirrhosis was accompanied by an improvement of their nutritional state. Even more important, there was an improvement of body cell mass and of muscle mass which both are of significantly prognostic value in this kind of patients. Dietary recommendations were not changed after TIPS but patients were able to realize them in a better way and they tolerated an increased intake of protein without an increase in the rate of hepatic encephalopathy. Furthe studies will have to be performed in order to find out the influences of different factors as reduced amount of ascites, improvement of intestinal absorption or avoiding of catabolic periods (gastrointestinal bleeding, paracentesis and endotoxinaemia by reduction of portal hypertension).

Estudos realizados em nosso laboratório encontraram que o aumento do conteúdo corporal de ácidos graxos N3, pela produção endógena via modificação genética, protege camundongos do ganho de peso corporal e obesidade induzida por dieta hiperlipídica. Objetivo: Investigar os mecanismos pelos quais o óleo de peixecontrola o balanço energético de camundongos C57BL6/J e UCP1selvagens e Knockout (KO) protegendo do desenvolvimento da obesidade induzida por dieta, com ênfase nos processos termogênicos dependentes e independentes da UCP1. Materiais e Métodos: Protocolo 1- Camundongos C57BL6/J alimentados por 8 semanas com dieta normal (DN) contendo 10% de lipídeos oriundos do óleo de soja e banha de porco, dieta normal N3 (DNN3) contendo 10% de lipídeos oriundos do óleo de soja e óleo de peixe, dieta hiperlipídica (HFD) contendo 60% de lipídeos oriundos do óleo de soja e banha de porco e dieta hiperlipídica (HFDN3) contendo 60% de lipídeos oriundos do óleo de soja e óleo de peixe foram avaliados para o peso corporal, a eficiência energética, a ingestão alimentar, a calorimetria indireta, a adiposidade, a tolerância à glicose e à insulina, o consumo de oxigênio tecidual e a análise lipidômica do tecido adiposo inguinal (TAI) e marrom (TAM). Protocolo 2- Camundongos selvagens e Knockout para a UCP1 alimentados por 8 semanas com dieta (HFD) e (HFDN3) foram avaliados para o peso corporal, a eficiência energética, a ingestão alimentar, a calorimetria indireta, a adiposidade, a tolerância à glicose, e o consumo de oxigênio tecidual. Resultados: Protocolo 1- Não houve diferenças significativas no ganho de peso, adiposidade, ingestão alimentar, consumo de oxigênio e tolerância à glicose entre camundongos C57BL6/J alimentados com as dietas DN e DNN3. Entretanto, aqueles alimentados com dieta HFDN3, apresentaram reduzido ganho de peso corporal, massa dos tecidos adiposos e eficiência energética quando comparados a camundongos alimentados com dieta HFD. Esses efeitos aconteceram na ausência de alterações significativas na ingestão alimentar medida tanto em gramas quanto em Kcal entre esses grupos. Corroborando a menor eficiência energética, camundongos C57BL6/J alimentados com dieta HFDN3 apresentaram maior consumo de oxigênio e similar atividade locomotora espontânea que camundongos alimentados com dieta HFD. Demonstramos que o consumo de oxigênio do TAI foi maior no grupo HFDN3 quando comparado ao grupo HFD. Por fim, a análise lipidômica do TAI e TAM revelou que a principal modificação ocorreu no enriquecimento dos triacilgliceróis (TAG) desses tecidos, sobretudo um aumento de ácidos graxos altamente insaturados (HUFA) nos TAG de camundongos alimentados com dieta HFDN3. Protocolo 2- Demonstramos que a dieta HFDN3 protege os camundongos UCP1 KO contra o ganho de peso corporal, aumenta o gasto energético e melhora à tolerância à glicose de maneira independente da UCP1. Além disso, observamos que o grupo UCP1 KO HFD aumentou a massa do TAM quando comparado aos outros grupos. Conclusão: A substituição da banha de porco pelo óleo de peixe na dieta aumenta o gasto energético de camundongos reduzindo o ganho de peso corporal e a adiposidade de maneira independente da UCP1. Digno de nota, o enriquecimento dos TAG com HUFA, pode ser um importante fenótipo para respostas observadas no balanço energético do grupo HFDN3 de ambos os protocolos. Acreditamos, em parte, que uma alta mobilização dos HUFA para a beta-oxidação possa estar acontecendo em paralelo com a ativação de vias alternativas de gasto energético. Os mecanismos responsáveis por estas ações serão investigados futuramente. / We have previously shown that diet-induced obesity is prevented by increasing N3 fatty acids content in the body of mice through genetic modification. Aim: In the present study, we investigated the mechanisms by which the fish oil control the energy balance protecting mice from diet-induced obesity, with emphasis at shivering and non-shivering thermogenesis. Materials and Methods: Protocol 1- C57BL6/J mice were fed during 8 weeks with normal diet (DN) containing 10% of lipids from soy oil and lard, normal diet N3 (DNN3) containing 10% of lipids from soy and fish oils, high fat diet (HFD) 60% of lipids from soy oil and lard and high fat diet (HFDN3) containing 60% of lipids from soy and fish oils. The evaluated parameters were body weight, energy efficiency, food intake, indirect calorimetry, adiposity, glucose and insulin tolerance, tissue oxygen consumption and lipidomic analysis of the white adipose tissue (WAT) and brown adipose tissue (BAT). Protocol 2- Wild type (WT) and UCP1 knockout (KO) mice were fed during 8 weeks with HFD and HFDN3. In Protocol 2, body weight, energy efficiency, food intake, indirect calorimetry, adiposity, glucose tolerance and tissue oxygen consumption were evaluated. Results: Protocol 1- No significant differences were observed in body weight, adiposity, food intake, oxygen consumption and glucose tolerance between mice fed with DN and DNN3. Mice fed with HFDN3, however, displayed reduced body weight gain, epididimal, inguinal and retroperitoneal adipose tissue masses, and energy efficiency when compared to mice fed with HFD. These effects occurred in the absence of significant alterations in food intake measured in grams and Kcal. Corroborating the decrease in energy efficiency, C57BL6/J mice fed with HFDN3 have increased oxygen consumption, but similar spontaneous locomotor activity when compared to mice fed with HFD. We show that oxygen consumption in the WAT in mice fed with HFDN3 was higher than in mice fed with HFD. Finally, the lipidomics analysis in both WAT and BAT revealed an enrichment of the triacylglycerol (TAG) linked to highly unsaturated fatty acids (HUFA, 46 double bonds) in mice fed with HFDN3. Protocol 2- The HFDN3 protects both WT and UCP1 KO groups from body weight gain, increases energy expenditure, and improves glucose tolerance. Moreover, we observe that UCP1 KO HFD group increased the weight of the TAM relative to the other groups. Conclusion: Our results indicate that replacement of lard by fish oil in the diet of mice increases energy expenditure independently of UCP1, decreasing the gain in body weight and adiposity in both protocols. To account for these findings, a model based on the higher mobilization of TAG linked to HUFA for beta-oxidation (relative to less unsaturated moieties) and activation of alternative mechanisms of energy expenditure are proposed to explain the lean phenotype of mice fed with HFDN3. This and other mechanisms of energy expenditure, however, require further investigations.

Zahlreiche Forschungsarbeiten haben gezeigt, dass nicht nur Menschen, sondern auch Tiere konstante individuelle Unterschiede im Verhalten aufweisen. Zu verstehen warum sich diese Verhaltensunterschiede im Laufe der Evolution entwickelt haben, ist ein Ziel dieses Forschungsbereiches. In dieser Arbeit wurde untersucht wie verschiedene Modulatoren das Nahrungssuchverhalten von Blütenfledermäusen (Glossophaginae) beeinflussen um individuelle Verhaltensunterschiede zu quantifizieren und theoretische Vorhersagen zu testen. Alle Experimente wurden in naturnaher Umgebung mit programmierbaren, künstlichen Blüten durchgeführt. Es wird angenommen, dass die Plastizität von Verhalten ein generelles Merkmal ist in dem sich Tiere unterscheiden, da manche Individuen allgemein stärker auf Reize aus der Umwelt reagieren könnten als andere. Um diese Vorhersage zu testen, wurde die Nahrungsverfügbarkeit experimentell manipuliert und zwei Arten von Verhaltensplastizität in denselben Individuen gemessen. Die Ergebnisse unterstützen diese Annahme jedoch nicht, da die beiden Arten von Verhaltensplastizität nicht korrelieren. Neben Umwelteinflüssen können auch innere Merkmale wie die Stoffwechselrate das individuelle Nahrungssuchverhalten beeinflussen. Die Ergebnisse zeigen, dass sich die Individuen in ihrem täglichen Energieverbrauch unterscheiden und dass diese Unterschiede mit dem Explorationsverhalten während der Nahrungssuche korrelieren. Zusätzlich kann das individuelle Nahrungssuchverhalten auch von sozialen Faktoren beeinflusst werden. Bei limitierter Nahrungsverfügbarkeit verteidigen einzelne Männchen Blüten gegen andere Männchen, jedoch nicht gegenüber Weibchen. Individuelle Unterschiede in der Aggression und Aktivität werden dagegen nicht von der sozialen Gruppenzusammensetzung beeinflusst. In dieser Arbeit wurden nicht nur individuelle Unterschiede im Nahrungssuchverhalten von Blütenfledermäusen bestimmt, sondern auch Vorhersagen aus dem Bereich der Persönlichkeitsforschung bei Tieren überprüft. / Animal personality research has shown that animals express individual differences in their behavior that are consistent over time and/or across situations. Furthermore, animal personality research aims to understand how these individual differences in behavior evolve and how they are maintained within populations. This thesis focuses on how different modulators influence the foraging behavior of nectar-feeding bats (Glossophaginae) in order to investigate consistent individual differences in their behavior and to test predictions proposed in the field of animal personality. All experiments were conducted in a semi-natural environment by using a setup of computer-controlled artificial flowers. One prediction of animal personality research is that behavioral plasticity is a single trait in which individuals differ because some individuals might be generally more responsive to changes in the environment than others. In order to test this prediction, resource availability was manipulated and two types of behavioral plasticity were quantified within the same individual. However, the two types of plasticity did not correlate and therefore this hypothesis was not supported. Individual foraging behavior can not only be modulated by changes in the environment but also by individual differences in internal traits like metabolic rates. Experiments confirmed that individual differences in daily energy expenditure correlated with consistent individual differences in exploration. Additionally, foraging behavior can also be modulated by social factors. When resources are limited some males started to defend flowers against other males but not against females. Furthermore, it could be shown that individual differences in aggression and activity are internally driven and not influenced by changes in the social group composition. This thesis not only assessed individual differences in the foraging behavior of nectar-feeding bats but also investigated predictions proposed in the field of animal personality research.

O gasto energético total (GET) pode ser usado como medida da ingestão energética (IE). Existe um constante sub-relato da IE obtida por métodos de avaliação do consumo alimentar, mas poucos estudos o investigaram em nações em desenvolvimento. Objetivos: a) comparar a validade das estimativas de IE de um questionário de freqüência alimentar, três recordatórios alimentares e um diário alimentar de três dias, segundo a água duplamente marcada; b) determinar a influência da prática de atividade física, do índice de massa corporal e de fatores psicossociais no sub-relato e; c) comparar as taxas de sub-relato entre agrupamentos de padrões alimentares. Métodos: Sessenta e cinco mulheres responderam aos métodos de inquérito supracitados, a partir dos quais foi estimada a IE. O GET foi medido pela água duplamente marcada. A prática de atividade física, índice de massa corporal, escolaridade, renda, idade, conhecimento nutricional, insatisfação corporal, restrição dietética, compulsão alimentar e o desejo de aceitação social foram correlacionados ao sub-relato. Os padrões alimentares foram obtidos pela análise de cluster. Resultados: O GET foi de 2.622 ± 490 kcal, enquanto que a IE, mensurada respectivamente pelo recordatório, diário e questionário, foi de 2.078 ± 430 kcal; 2.044 ± 479 kcal e 1.984 ± 832 kcal. A proporção de sub-relatores foi de 24,6% para o recordatório, 29,2% para o diário e 53,8% para o questionário (p < 0,005). Os sub-relatores apresentaram menores médias de renda e escolaridade e maiores valores de idade, insatisfação corporal e desejo de aceitação social. O sub-relato foi mais comum no padrão alimentar mais frugal. Conclusão: Os três métodos de avaliação do consumo alimentar apresentaram erros sistemáticos, embora o questionário de freqüência alimentar tenha tido o pior desempenho. O sub-relato foi influenciado por diversos fatores psicossociais e variou conforme o padrão alimentar relatado, o que pode comprometer a avaliação do consumo / Total energy expenditure (TEE) may be used as a measure of energy intake (EI). There is a constant underreporting of EI obtained by dietary assessment methods, but few studies have investigated it in developing nations. Objectives: a) to compare the validity of EI estimates obtained by a food-frequency questionnaire, three diet recalls and a three-day food record; b) to determine the influence of physical activity, body mass index and psychosocial factors on underreporting and; c) to compare underreporting rates between dietary pattern\'s clusters. Methods: Sixty-five women completed the dietary assessment methods, which were used to estimate EI. TEE was measured by doubly labeled water. Physical activity practice, body mass index, education, income, age, nutritional knowledge, body dissatisfaction, dietary restraint, binge eating and social desirability were correlated to underreporting. Dietary patterns were obtained by cluster analysis. Results: TEE was 2,622 ± 490 kcal, while EI, measured respectively by the diet recall, food record and food-frequency questionnaire, was 2,078 ± 430 kcal; 2,044 ± 479 kcal and 1,984 ± 832 kcal. Proportion of underreporters was 24.6% (recall), 29.2% (record) and 53.8% (questionnaire) (p < 0.005). Underreporters had smaller income and education and greater age, body dissatisfaction and social desirability. Underreporting was more common in the \'frugal foods\' pattern. Conclusions: The three dietary assessment methods presented systematic errors, although the foodfrequency questionnaire had the worst performance. Underreporting was influenced by psychosocial factors and varied according the reported dietary pattern, which may compromise dietary assessment

Os jogos de realidade virtual (JRV) são utilizados como estratégia complementar de reabilitação motora em indivíduos pós-acidente vascular cerebral (AVC). Porém, o impacto cardiovascular e metabólico desses jogos foi pouco investigado, o que é essencial para uma reabilitação completa. Com esse intuito, este estudo avaliou as respostas de frequência cardíaca (FC) e consumo de oxigênio (VO2) durante os JRV, comparando-as ao limiar anaeróbio (Lan) e ao ponto de compensação respiratória (PCR) e calculando o gasto energético (GE). Além disso, investigou-se as respostas da FC, pressão arterial (PA) e duplo produto (DP) no período pós-JRV e a reprodutibilidade de todas as respostas aos JRV. Para tanto, 12 indivíduos (84% homens, 56±12 anos) em fase crônica após um único AVC participaram, em ordem aleatória, de três sessões experimentais, sendo duas delas de JRV e uma controle. Nas sessões de JRV, os indivíduos foram submetidos a 4 blocos de jogos intercalados por 2 min de pausa; cada bloco foi composto por 3 min do jogo Tênis de Mesa, seguidos de 1 min de pausa e 4 min do jogo Boxe (Xbox360+Kinect). Na sessão controle, os indivíduos assistiram a um filme sentados por 38 min. A FC e o VO2 foram continuamente medidos durante as sessões, e a PA e FC foram medidas antes e aos 15 e 30 min após as intervenções. O GE foi calculado a partir do VO2. As respostas de FC e VO2 nos JRV tiveram boa reprodutibilidade (coeficiente de correlação intraclasse > 0,75 e baixo erro médio da medida). Os valores de FC medidos durante os JRV foram semelhantes ao Lan e significantemente inferiores ao PCR, com mais de 50% dos indivíduos apresentando FC abaixo do Lan em todos os JRV. O VO2 medido durante os JRV foi significantemente menor que o Lan e o PCR, com mais de 75% dos indivíduos com VO2 abaixo do Lan em todos os jogos. O GE médio da sessão de JRV foi de ? 4,6±0,1 kcal/min, totalizando 169±11 kcal. Após a sessão de JRV, a PA não se modificou, a FC e o DP permaneceram aumentados por 30 min. Conclui-se que, em indivíduos pós-AVC, a sessão de JRV proposta promoveu respostas fisiológicas reprodutíveis, que corresponderam a uma intensidade próxima e abaixo do Lan, gerando um GE médio de cerca de 4 kcal/min (3 METS) e mantendo o trabalho cardíaco aumentado por até 30 min após a sessão / Virtual reality games (VRG) has been used as a complementary strategy for motor rehabilitation in stroke survivors. However, the cardiovascular and metabolic impacts produced by these games has been poorly investigated, which is important for a complete rehabilitation. To investigate this impact, this study evaluated heart rate (HR) and oxygen consumption (VO2) responses during VRG, comparing these responses with anaerobic threshold (AT) and respiratory compensation point (RCP), and calculating the energy expenditure (EE). Furthermore, the responses of HR, blood pressure (BP) and rate pressure product (RPP) after the VRG session as well as the reproducibility of all the responses to VRG were evaluated. For that, 12 chronic post-stroke patients (84% men, 56±12 years) underwent, in random order, 3 experimental sessions: two composed by VRG and one control session. The VRG sessions were composed by 4 blocks of games interpolated by 2 min of rest, and each block was composed by 3 min of the table tennis game followed by 1 min of rest and 4 min of the boxing game (Xbox360+Kinect). In the control session, the subjects watched a film in the seating position for 38 min. HR and VO2 were continuously measured during the sessions, and HR and BP were also measured before and at 15 and 30 min after the interventions. EE was calculated from VO2. HR and VO2 responses to VRG showed good reproducibility (intraclass correlation index > 75% and low standard error of measurement). HR measured during the VRG was similar to AT and significantly lower than RCP, with more than 50% of the subjects presenting HR below AT in all the games. VO2 measured during the VRG was significantly lower than AT and RCP, with more than 75% of the subjects presenting VO2 below AT in all the games. VRG EE was ?4.6±0.1 kcal/min, totalizing 169±11 kcal. After the VRG session, BP did not change, while HR and RPP remained significantly increased up to 30 min. In conclusion, in post-stroke survivors, the proposed VRG session produced physiological responses that have good reproducibility and corresponded to an intensity near to and below the AT, generating a mean EE of 4 kcal/min (3 METs), and maintaining cardiac work elevated for at least 30 min after its end

Thesis (Ph.D. (Electronical Engineering))--North-West University, Potchefstroom Campus, 2008.

In schizophrenia, subtle aberrations in the brain cause functional disturbances like psychotic symptoms and social disability. There are, however, also disturbances outside the CNS indicating a systemic manifestation in the disease. The aim of the present thesis was to gain deeper understanding of the pathophysiological mechanisms underlying schizophrenia with a particular interest in peripheral and systemic manifestations with relevance for the increased risk of obesity and metabolic complications seen in the disease. Therefore, resting energy expenditure (REE), physical capacity, and relevant body composition variables were measured in patients with schizophrenia and in healthy controls. Also niacin skin flush response and electrodermal activity (EDA) were studied. Patients with schizophrenia exhibited significantly lower REE expressed as kJ/kg, and also lower values compared with predicted levels than the controls. The difference could not be attributed to medication or variations in body composition between the two groups. There was a gender difference with the lowest levels found in male patients. Male patients exhibited significantly lower physical capacity in terms of predicted maximal oxygen uptake capacity and faster increase in respiratory quotient than male controls. The oral niacin test revealed a significantly delayed skin flush reaction in patients compared with controls. The patients also exhibited lower EDA response. There was a significant association in response patterns for the niacin and the EDA tests in the patients, but not in controls. In a test-retest study in patients there was acceptable stability for EDA measures but low test-retest stability for niacin variables. The previously found association in responses for the two tests was, however, replicated. The results gain support for the concept of schizophrenia as a disease with systemic manifestations including metabolic dysregulation. The findings add to the understanding of the weight gain and the increased risk for cardiovascular morbidity seen in this condition.

Purpose: The purpose of this study was to investigate if there was any difference in energy expenditure (kcal/min) and oxygen consumption (VO2) between subjects walking with Masai Barefoot Technology ® (MBT) shoes and regular orthopedic shoes. The research hypothesis was that MBT shoes demand more energy expenditure than regular orthopedic shoes. Methods: Seven women aged 49-65 were recruited for the study. The subjects were tested in two sessions, with a minimum of two weeks in between each sesssion. On each test session the subjects walked with both MBT shoes and orthopedic shoes which were adjusted in mass (g) to match the mass of the MBT shoes. While the subjects walked on a treadmill, the oxygen consumption (VO2), heart rate (min-1) and self selected velocity (m/s) for each of the shoe types was measured. Results: Results showed that there is no significant difference in oxygen consumption (VO2) between the MBT and orthopedic shoes. Energy expenditure (kcal/min) was also calculated from the data and the results revealed that there is no significant differ-ence between MBT and orthopedic shoes in energy expenditure (kcal/min) either. The self selected velocity (m/s) between the two shoe types was also found to be insignificant. Conclusion: The results showed no significant difference between the shoes. This could indicate that the specific construction of the MBT shoe has no effect on the energy expenditure (kcal/min) of its user. This lack of difference may be due to the equal mass of the shoes, but since oxygen consumption (VO2) was not investigated in orthopedic shoes with different shoe masses, this conclusion cannot be confirmed. The self selected velocity (m/s) was found to be insignificant and this finding could suggest to that prolonged usage of the MBT shoe may diminish gait parameters dissimilarities during ambulation. This study should therefore be seen as a pilot study and further investigation in this area should be pursued.

Bewegungsmangel und seine Folgen bilden derzeit einen Forschungsschwerpunkt im Kontext sportwissenschaftlicher Fragestellungen. Der Fokus liegt dabei zumeist auf Berufsgruppen mit sitzender Tätigkeit und bestehendem Übergewicht. Unbe-rücksichtigt bleiben jedoch Zielgruppen mit intensiver berufsbedingter körperlicher Aktivität. Resultierend aus der Diskrepanz zwischen hoher körperlicher Aktivität im Beruf und gleichzeitigem Übergewicht bildet die Frage nach der Energiebilanz bei Forstwirten die Grundlage der vorliegenden Studie. Hierzu wird die Energieauf-nahme dem Energieumsatz gegenübergestellt, um Schlussfolgerungen aus der hohen körperlichen Aktivität und dem gleichzeitig bestehenden Übergewicht der Forstwirte ziehen zu können. Die Ermittlung des Energieumsatzes wurde mit Aktivitätsprotokollen und mit indi-rekter Kalorimetrie bei typischen beruflichen Tätigkeiten umgesetzt. Darüber hin-aus wurden Ernährungsprotokolle zur Bestimmung der Energieaufnahme und Er-hebungen zu äußeren Bedingungen und zur Körperkomposition durchgeführt. Die Messungen wurden über einen Messzeitraum von sieben Tagen zu drei Messzeit-punkten (t1=Winter, t2=Frühjahr, t3=Sommer) durchgeführt, um das saisonale Be-lastungsprofil der Forstwirte und die damit einhergehenden unterschiedlichen be-ruflichen Tätigkeiten zu berücksichtigen. Bei der Energieaufnahme konnte in t1 der höchste Wert verzeichnet werden (3135 kcal pro Tag). Bei allen drei Messzeitpunkten deckte die Energieaufnahme den Energiebedarf eines Mittelschwerarbeiters. Die Energieumsätze während der einzelnen beruflichen Tätigkeiten lagen zwischen 6,6 kcal/min beim Wegebau und 9,4 kcal/min bei der Holzernte und entsprechen einem Metabolic Equivalent of Task (MET) von 5-7, welche in den Bereich der Schwerstarbeit einzuordnen war. In allen drei Messzeitpunkten konnte eine negative Energiebilanz festgestellt wer-den, die im Gegensatz zur Entwicklung der Körperkomposition (t3=20,81%) und der steigenden BMI-Werte stand (t3=27,3). Es lässt sich ein Belastungsprofil ver-muten, das in verschiedene Phasen eingeteilt ist, welche in ihrer Belastungsinten-sität variieren und über einen mehrtägigen Zeitraum andauern.

No description available.