The global intent of this research was to confirm the validity of the interpolated twitch technique (ITT) to voluntary torque model (first study) and then to utilize this technique in developing definitive criterion measures enhancing the study of training strategies on central fatigue (second study) and velocity specific (third study) voluntary activation (VA) and force production outcomes. The first study assessed the contribution of non-stimulated synergists to the non-linearity of the ITT voluntary torque relationship for elbow flexion contraction. Since multiple synergist stimulation was found not to significantly improve the ITT to voluntary torque relationship, follow-up pilot work was conducted in which the quadriceps femoris was identified as a valid ITT test model muscle. The first training study investigated the effects of high volume, maximum voluntary isometric contraction (MVIC) resistance training of the quadriceps femoris on MVIC levels of force and VA prior to, during, and recovery from a standardized fatigue test protocol. Results showed significant increases in pre-fatigue MVIC VA and force, increases in resistance to early fatigue, but also increased overall rate of fatigue resulting in non-significant changes in total force volume and endurance time. Post-fatigue analysis showed significant training increases in rate and level of recovery for both MVIC VA and force production. The second training study investigated the effects of high resistance ramp versus ballistic type MVIC strength training of the quadriceps femoris on central adaptations in submaximal and maximal levels of MVIC VA and force production. Results showed similar ramp and ballistic group training increases in MVIC force and VA on both ramp and ballistic tests. Ballistic group, ballistic test change scores were significant but not for the ramp test, suggesting ballistic group test-training specificity. The ballistic group showed significant force increases on the submaximal 150ms ballistic test, while the ramp group showed non-significant training changes, further supporting test-training specificity for the ballistic group. Results support utility of the ITT and provide valuable information with regard to training and test-training specificity considerations.

L'optimisation de la performance oblige l'athlète à répéter des séances d'entraînement à haute intensité de travail avec peu de récupération, ce qui génère une fatigue neuromusculaire qui peut être préjudiciable. Ainsi, dans le but de limiter ce phénomène et d'améliorer l'efficacité des séances d'entraînement, le choix d'une récupération adéquate s'impose.La récupération active est la méthode la plus connue et la plus efficace relatée dans la littérature. En effet, de nombreuses études démontrent son effet bénéfique sur la fatigue provoquée lors d'exercices globaux (types course ou pédalage). Cette modalité de récupération correspond à un exercice musculaire léger permettant une augmentation du flux sanguin périphérique et une élimination plus rapide des métabolites. A l'heure actuelle, peu d'études se sont intéressées à la récupération active appliquée de manière locale pour des exercices de renforcement de groupes musculaires spécifiques.L'objectif de ce travail était donc d'étudier la méthode la plus efficace, en termes de modalité et de moment d'application, pour récupérer la force maximale de l'athlète lors d'un exercice de renforcement musculaire. De plus, afin d'assurer une application de cette récupération active, spécifiquement sur les groupes musculaires souhaités, nous avons utilisé l'électromyostimulation (EMS).Nos différents résultats suggèrent qu'il n'est pas nécessaire d'appliquer une modalité particulière pour la récupération des exercices de renforcement musculaire réalisés à intensité maximale. En effet, la récupération active par EMS appliquée au cours d'une séance (entre les séries) ou après une séance ne montre pas de différence avec une récupération passive. De plus, l'application proximale ou distale de l'EMS n'a pas d'influence sur la cinétique de récupération. L'approche neuromusculaire de la fatigue, montre cependant, qu'il s'avère nécessaire d'analyser l'origine des perturbations engendrées par l'exercice, afin de choisir la modalité de récupération la mieux adaptée

Neįprasti didelio intensyvumo (ypač ekscentriniai) raumenų susitraukimai gali sukelti raumenų pažaidą (Yanagisawa et al., 2011; Neme et al., 2013), kuri pasireiškia sumažėjusia raumenų susitraukimo jėga Byrne et al., 2004; Skurvydas et al., 2010) miofibrilių Z linijos morfologiniais pokyčiais (Feasson et al., 2002), baltymų ištekėjimu iš pažeistų raumens skaidulų, raumenų skausmu, patinimu ir padidėjusiu standumu (Malisoux et al., 2006; Chen et al., 2013). Pažaida dažna pradėjus intensyviai treniruotis po santykinai mažo fizinio aktyvumo laikotarpio arba kaitant krūvio parametrus (intensyvumą, apimtį) siekiant išvengti monotonijos ir sukelti didžiausią adaptacinį atsaką (Bompa, 1999; Issurin, 2010). Ankstesniuose tyrimuose taikyti vienodo dydžio krūviai neatitinka sportinių pratybų specifiškumo (Nosaka, Clarkson, 1995; Chen, Hsieh, 2001): pratybose krūvio apimtis ir intensyvumas nuolatos keičiami, taikomos įvairios krūvio didinimo strategijos. Išlieka neaišku, kaip kinta raumenų pažaida ir motorinė funkcija didinant fizinį krūvį taikant skirtingas strategijas. Kėlėme hipotezę, kad: 1) nuosekliai didinamas krūvis sukelia mažesnę raumenų pažaidą, palyginti su staigiai didinamu krūviu, nes motorinė sistema labai jautriai reaguoja į krūvio didinimo greitį; 2) treniruotės ciklo metu periodiškai pasireiškianti didesnė raumenų pažaida dėl superkompensacijos gali sukelti didesnę ilgalaikę griaučių raumenų adaptaciją (masės ir jėgos prieaugį). R. Lynn ir D. L. Morgan (1994) nustatė... [toliau žr. visą tekstą] / Unaccustomed muscle exercise, especially when it involves high-strain eccentric contractions, causes muscle damage (Yanagisawa et al., 2011; Neme et al., 2013). Muscle damage manifests in altered Z-disk morphology (Feasson et al., 2002), prolonged impairment of muscle force (Byrne et al., 2004; Skurvydas et al., 2010), protein leakage from injured muscle fibres, delayed-onset muscle soreness, and increased passive muscle stiffness and swelling (Malisoux et al., 2006; Chen et al., 2013). Muscle damage is frequently induced by sports training, where physical load parameters are being varied on the temporal scale to avoid monotony and maximize the adaptations (Bompa 1999; Issurin, 2010). However, there are limited data on the development of muscle damage and its impact on muscle function when variant exercise training schemes are applied. More needs to be learned about the impact of different strategies of load increase on exercise-induced muscle damage in order to identify progression regimes that can optimize neuromuscular adaptation processes. Therefore, we have followed the dynamics of muscle function during the stretch–shortening exercise with differently increasing load. We increased training stimulus by varying the volume, intensity, and range of motion. According to Nosaka (2008), these components of the eccentric contraction training are the most important for adaptation of the skeletal muscle. We hypothesized that the progressive increase in training load would induce... [to full text]

Syfte Syftet med litteraturstudien var att göra en granskning av vetenskapliga studier med avsikt att undersöka vilotidens effekt för styrkeutveckling i musculus quadriceps femoris. Med vilotid avses vilan mellan seten vid aktuellt träningstillfälle samt antal träningstillfällen per vecka.   Frågeställningar: 1. Hur ser sambandet ut med avseende på vilan mellan seten och styrkeutvecklingen? 2. Hur påverkar antal träningstillfällen per vecka styrkeutvecklingen?   Metod En systematisk litteraturstudie genomfördes i de utvalda databaserna PubMed, SportDiscus, Cochrane och PEDro. Specifika sökord och kombinationer av dessa utgjorde en grund för sökningarna. Inklusions- och exklusionskriterier formulerades för att hitta relevanta artiklar. Fem artiklar inkluderades och kvalitetsgranskades med hjälp av PEDro scale, för att sedan rangordnas efter kvalitet.   Resultat De inkluderade artiklarna hade en medelgod kvalitet enligt PEDro scale. En längre vila mellan seten gav mer ökning i styrka i m. quadriceps femoris än en kortare vila. Tre träningstillfällen per vecka gav en större styrkeutveckling än färre gånger hos vuxna män och kvinnor. För äldre gav en till två träningstillfällen per vecka samma styrkeutveckling som tre träningstillfällen per vecka.   Slutsats Det behövs mer forskning med högre kvalitet än den som hittats i denna studie. Detta för att kunna klargöra vilan mellan setens effekt på styrkeutveckling. En vila längre än 160 sekunder behöver också utforskas. Antal träningstillfällen per vecka verkar dock ha större betydelse för vuxna män och kvinnor än för äldre män och kvinnor.

Thesis (Ph.D.)--University of Alberta, 2009. / A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Doctor of Philosophy, Centre for Neuroscience. Title from pdf file main screen (viewed on October 11, 2009). Includes bibliographical references.

O exercício excêntrico é utilizado como uma estratégia de treinamento de força em atletas e sujeitos saudáveis de diferentes faixas etárias. Esse tipo de exercício também é largamente difundido na área da reabilitação musculoesquelética, sendo o quadríceps femoral o músculo mais frequentemente investigado devido à sua relevância clínica. O tema dessa tese de Doutorado é a adaptação do sistema neuromuscular ao treinamento excêntrico de extensores de joelho. No Capítulo I, um estudo de revisão procurou descrever os diferentes métodos empregados pelos cientistas para o treinamento excêntrico de extensores de joelho, assim como avaliar as adaptações neurais, morfológicas e na produção de força muscular de sujeitos saudáveis. Após busca sistematizada nas bases de dados, 26 estudos foram incorporados ao nosso estudo de revisão. Os programas de treinamento excêntrico realizados em dinamômetro isocinético e em equipamentos isotônicos (leg-press e cadeira extensora de joelho) foram descritos e discutidos. Os resultados desses estudos indicam um efeito positivo do treinamento excêntrico sobre a força e a ativação muscular, especialmente em testes excêntricos, assim como uma significativa resposta hipertrófica. Porém, resultados conflitantes e lacunas identificadas na literatura incentivaram a realização de dois estudos originais para verificar: (1) o comportamento temporal das adaptações neurais e morfológicas ao treinamento excêntrico de extensores de joelho e suas contribuições para os ganhos de força (Capítulo II); e (2) as adaptações específicas de músculos sinergistas da extensão de joelho: reto femoral (RF) e vasto lateral (VL) (Capítulo III). Vinte homens saudáveis realizaram um período controle de quatro semanas sem treinamento, seguido por um programa de 12 semanas de treinamento excêntrico em dinamômetro isocinético. Avaliações de torque, eletromiografia e ultrassonografia de extensores de joelho foram realizadas a cada quatro semanas. Um maior ganho de força foi verificado nos testes excêntricos, seguido pelos testes isométricos e concêntricos. A ativação muscular nos testes excêntricos e isométricos aumentou após quatro e oito semanas de treinamento, respectivamente, ao passo que os testes concêntricos não apresentaram alteração da atividade eletromiográfica. Os valores de espessura muscular, área de secção transversa anatômica e comprimento de fascículo aumentaram após quatro e oito semanas de treinamento, mas não modificaram entre a oitava e a 12ª semana de intervenção. As adaptações na geometria fascicular dos músculos RF e VL foram semelhantes ao longo do programa de treinamento. Nossos achados sugerem que: (1) existe um forte efeito da especificidade do exercício excêntrico sobre os aumentos de força e ativação muscular; (2) os ganhos de força excêntrica e isométrica até a oitava semana de treinamento estão relacionados a adaptações neurais e morfológicas mensuráveis, enquanto outros mecanismos podem estar relacionados aos ganhos nas quatro últimas semanas de intervenção; (3) o ganho de força concêntrica não é afetado por adaptações neurais; (4) o treinamento excêntrico aumenta o comprimento, mas não o ângulo de penação fascicular; (5) as adaptações na arquitetura muscular podem ocorrer nas primeiras semanas de treinamento; e (6) apesar das diferenças estruturais e funcionais, RF e VL apresentam índices semelhantes de adaptação. / Eccentric exercise is used as a strategy for strength training in athletes and healthy subjects with different ages. This type of exercise is also frequently used in musculoskeletal rehabilitation, and the quadriceps femoris is the most frequently investigated muscle due its clinical relevance. The theme of this PhD thesis is the adaptation of the neuromuscular system to knee extensor eccentric training. In Chapter I, a review study aimed at describing the different methods employed by scientists for knee extensor eccentric training, as well as for evaluating the neural, morphological and muscular strength adaptations in healthy subjects. After a systematized search in related data bases, 26 studies were incorporated to our review study. Eccentric training programs performed in isokinetic dynamometers and isotonic devices (leg-press and knee extension chair) were described and discussed. Results from these studies indicate a positive effect of eccentric training on muscle strength and activation, especially in eccentric tests, as well as a significant hypertrophic response. However, conflicting results and gaps observed in the literature encouraged us to perform two original studies to verify: (1) the time course of neural and morphological adaptations to knee extensor eccentric training and their contribution to strength gains (Chapter II); and (2) the specific adaptive responses from synergistic knee extensor muscles: rectus femoris (RF) and vastus lateralis (VL) (Chapter III). Twenty healthy men performed a four-week control period without training, followed by a 12-week eccentric training on an isokinetic dynamometer. Knee extensor evaluations of torque, electromyography and ultrasonography were made every four weeks. A higher strength increase was observed in eccentric tests, followed by isometric and concentric tests. Muscle activation in eccentric and isometric tests increased after four and eight weeks of training, respectively, while the concentric tests presented no change in the electromyographic activity. Muscle thickness, anatomical cross-sectional area and fascicle length values increased after four and eight weeks of training, but did not change between the eighth and twelfth intervention week. Adaptations in RF and VL fascicular geometry were similar throughout the training program. Our findings suggest that: (1) there is a strong specificity effect of eccentric exercise on increases in muscle strength and activation; (2) eccentric and isometric strength gains up to the eighth week of training are related to measurable neural and morphological adaptations, while other mechanisms may be related to strength increase in the last four weeks of intervention; (3) concentric strength gain is not affected by neural adaptations; (4) eccentric training increases fascicle length, but not pennation angle; (5) muscle architecture adaptations may occur in the first weeks of training; and (6) despite the structural and functional differences, RF and VL present similar adaptation levels.

ACL injuries are severe injuries and also the most common diagnosis among alpine skiers. The purpose of this study was to evaluate alpine skiers isokinetic strength and the risk of ACL injury. 31 alpine skiers were included in this study, 17 men and 14 women, who had conducted physiological assessments between 1999 and 2007 during their active careers. The participants were sent an online questionnaire in 2018 regarding ACL injuries during their active alpine careers. The risk of injury was then evaluated by comparing injured athletes concentric isokinetic strength, hamstring to quadriceps ratio and limb symmetry index with non-injured athletes. Results showed a significant likelihood of injury for having a lower hamstring to quadriceps ratio in the left limb but not in the right limb. There was no significant likelihood of injury and having a greater limb asymmetry. Because of the small number of participants and few ACL injured there is difficult to draw any conclusions. However, there seems to be a relationship of having a lower H/Q ratio on the left limb and the risk of ACL injury. Further research is recommended.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-02-03T21:41:35Z No. of bitstreams: 1 DinaLilliaOliveiraDeAzevedo_TESE.pdf: 1220898 bytes, checksum: ede080e8b66e3ed28eed0d6833c1ddf8 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-02-04T19:56:56Z (GMT) No. of bitstreams: 1 DinaLilliaOliveiraDeAzevedo_TESE.pdf: 1220898 bytes, checksum: ede080e8b66e3ed28eed0d6833c1ddf8 (MD5) / Made available in DSpace on 2016-02-04T19:56:56Z (GMT). No. of bitstreams: 1 DinaLilliaOliveiraDeAzevedo_TESE.pdf: 1220898 bytes, checksum: ede080e8b66e3ed28eed0d6833c1ddf8 (MD5) Previous issue date: 2014-09-30 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPq / As decis?es comportamentais de um animal n?o ocorrem de forma aleat?ria, uma vez que os comportamentos s?o ajustados para garantir a sobreviv?ncia e a reprodu??o do animal. Nesta pesquisa, examinei decis?es comportamentais no contexto de forrageamento da formiga Dinoponera quadriceps com rela??o ? orienta??o, avalia??o do alimento e din?mica do forrageio ao n?vel do indiv?duo. O estudo foi realizado no Laborat?rio de Biologia Comportamental na UFRN e em uma ?rea de Mata Atl?ntica secund?ria na FLONA-ICMBio de N?sia Floresta/RN. Em todas as observa??es e experimentos as formigas foram marcadas individualmente com uma etiqueta, com c?digo alfanum?rico, colada no t?rax. Na primeira parte do estudo analisei as pistas de orienta??o utilizadas por D. quadriceps. Em um labirinto de 17 compartimentos testei cada oper?ria forrageadora por 10 min em tr?s sess?es para seis tratamentos diferentes. Os tratamentos consistiam da presen?a ou aus?ncia de odor e de marcas visuais superiores ou frontais. As oper?rias demonstraram que a presen?a de odor ? indispens?vel e que marcas visuais frontais s?o mais eficazes do que as visuais superiores. Na segunda parte, investiguei a discrimina??o do alimento, considerando os par?metros tamanho, peso e volume. Em um experimento de ?cafeteria?, disponibilizei em uma placa de Petri, dentro de uma arena experimental de 1m?, peda?os de alimento (mortadela) de forma cil?ndrica. Inicialmente, os peda?os eram de quatro tamanhos diferentes; numa segunda etapa, os peda?os eram do mesmo tamanho, mas com peso diferente; na ?ltima etapa, os peda?os tinham mesmo peso, mas volume diferente. O resultado mostrou o efeito dos par?metros tamanho e peso para a escolha do alimento. Na terceira parte do estudo, avaliei a influ?ncia da atividade das forrageadoras ativas nas inativas. As col?nias foram observadas em ambiente natural. As observa??es aconteciam em tr?s dias consecutivos por 10 vezes, total de 30 dias para cada col?nia, 12 horas/dia. No primeiro dia, eu observava a sa?da e entrada das oper?rias; no segundo dia, foram retiradas as oper?rias mais ativas e devolvidas ao final das observa??es; no terceiro dia, as observa??es eram similares ao primeiro dia. Como resultado, as oper?rias de D. quadriceps realizam autoestimula??o e n?o facilita??o social e a col?nia compensa a falta das oper?rias mais ativas. Com base no exposto, eu concluo que as oper?rias de D. quadriceps usam pistas de orienta??o qu?mica e visual frontal e superior nos seus deslocamentos. Elas discriminam o alimento escolhido por tamanho e peso. A regula??o da din?mica de atividade das forrageadoras ? por autoestimula??o, uma oper?ria ativa n?o influencia a atividade de uma forrageadora inativa, o sucesso da busca pr?via ? um est?mulo para a pr?pria oper?ria bem sucedida continuar a atividade de forrageio / The behavioral decisions of animals do not occur randomly, because behaviors are adjusted to ensure the survival and reproduction of the animal. In this research, I examined behavioral decisions in the foraging context of the ant Dinoponera quadriceps with regard to orientation, food avaliation and foraging dynamic to individual level. The study was conducted at the Laboratory of Behavioral Biology at UFRN and in an area of secondary Atlantic Forest in FLONA-ICMBio N?sia Floresta/RN. In all observations and experiments, ants were marked individually with an alphanumeric code label fixed on the thorax. In the first part of the study, I analyzed the orientation cues used by D. quadriceps. The tests were performed in a maze of 17 compartments. Each forager was tested for 10 min in three sessions for six different treatments. The treatments consisted of the presence or absence of odor and superior or frontal visual cues. The workers demonstrated that the presence of odor is indispensable and front visual cues are more effective than superior visual cues. In the second part, I investigated the discrimination of food, considering the parameters, size, weight and volume. In a 'cafeteria' experiment, I offered cylindrical pieces of food (mortadella) in a Petri dish, within an experimental arena 1m?. Initially, the pieces were of four different sizes; in a second step, the pieces were of the same size but with different weight; in the last step, the pieces had the same weight but different volumes. The results showed the effect of the size and weight parameters for food choice. In the third part of the study, I evaluated the influence of the activity of active foragers on inactive ones. In this part, the colonies were observed in a natural environment. The observations took place on three consecutive days in 10 episodes, total of 30 days for each colony, 12 hours/day. On the first day, I registered the output and input of workers; on the second day, the most active ants on the first day were taken and given back at the end of the observations; on the third day, the observations were similar to the first day. As a result, the workers of D. quadriceps show autostimulation and they do not show social facilitation and the colony compensates the absence of the most active workers. Based on the stated, I conclude that workers of D. quadriceps use chemical, frontal and superior visual orientation cues during their displacements. They discriminate the chosen food by size and weight. The regulation of activity dynamics of foragers is by autostimulation, an active worker does not influence the activity of an inactive worker, the successful search previous is the stimulus to the successful worker itself to continue foraging activity.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-03-02T23:16:56Z No. of bitstreams: 1 WaldemarAlvesDaSilvaNeto_DISSERT.pdf: 468163 bytes, checksum: f08e3ba40bea69faf17f824fa2df41be (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-03-04T23:52:21Z (GMT) No. of bitstreams: 1 WaldemarAlvesDaSilvaNeto_DISSERT.pdf: 468163 bytes, checksum: f08e3ba40bea69faf17f824fa2df41be (MD5) / Made available in DSpace on 2016-03-04T23:52:21Z (GMT). No. of bitstreams: 1 WaldemarAlvesDaSilvaNeto_DISSERT.pdf: 468163 bytes, checksum: f08e3ba40bea69faf17f824fa2df41be (MD5) Previous issue date: 2014-08-26 / No presente trabalho, avaliamos o efeito da dist?ncia do alimento, sucesso de captura e tamanho do alimento e taxa de recompensa nas decis?es de forrageio tomadas por formigas da esp?cie Dinoponera quadriceps. Tamb?m investigamos, medindo o tempo de perman?ncia em cada ?rea, a influ?ncia do aprendizado no desempenho das oper?rias ao longo de sucessivas viagens. Foram simulados quatro cen?rios. Cada oper?ria realizou 10 viagens em cada cen?rio. Cen?rio 1: oper?rias sempre encontravam alimento de alta qualidade; Cen?rio 2: oper?rias encontravam alimento de alta qualidade em somente 50% das viagens; Cen?rio 3: oper?rias encontravam alimento de alta e baixa qualidade com probabilidades de ocorr?ncia de 0,5 para cada tamanho de alimento. Cen?rio 4: oper?rias tinham tr?s possibilidades, encontrar alimento de alta qualidade (33%), encontrar alimento de baixa qualidade (33%) e n?o encontrar alimento. Em todos os cen?rios, havia duas rotas poss?veis de explora??o, uma com 300 cm e outra com 600 cm de comprimento. A pesquisa mostrou que oper?rias da esp?cie D. quadr?ceps tendem a retornar ao mesmo local onde o alimento foi encontrado na viagem anterior, n?o importando a dist?ncia, tamanho do alimento ou taxa de recompensa. Nos casos de viagens sem captura, oper?rias eram mais propensas a trocar de ?rea em busca de alimento. No entanto, no cen?rio 4 essa decis?o de ?troca? foi menos evidente, possivelmente pela maior din?mica do cen?rio. Resultados tamb?m indicaram um processo de aprendizado das rotas de explora??o assim como das condi??es das ?reas de explora??o. Com a repeti??o das viagens, forrageadoras reduziram o tempo de busca nas ?reas nas viagens que n?o capturavam alimento e rapidamente trocavam de ?rea. / When searching for food, animals often make decisions of where to go, how long to stay in a foraging area and whether or not to return to the last visited spot. These decisions can be enhanced by cognitive traits and adjusted based on previous experience. In social insects such as ants, foraging efficiency have an impact on both individual and colony level. The present study investigated, in the laboratory, the effect of distance from food, capture success and food size, and reward rate on decisions of where to forage in Dinoponera quadriceps, a ponerine ant that forage solitarily and individually make their foraging decisions. We also investigated the influence of learning on the performance of workers over successive trips searching for food by measuring the patch residence time in each foraging trip. Four scenarios were created differing in food reward rates, food size offered and distances colony-food site. Our work has shown that as a rule-of-thumb, workers of D. quadriceps return to the place where a prey item was found on the previous trip, regardless of distance, food size and reward rate. When ants did not capture preys, they were more likely to change path to search for food. However, in one of the scenarios, this decision to switch paths when unsuccessful was less evident, possibly due to the greater variation of possible outcomes ants could experience in this scenario and cognitive constraints of D. quadriceps to predict variations of food distribution. Our results also indicated a learning process of routes of exploration as well as the food site conditions for exploration. After repeated trips, foragers reduced the patch residence time in areas that they did not capture food and quickly changed of foraging area, increasing their foraging efficiency.

Made available in DSpace on 2014-12-17T15:36:57Z (GMT). No. of bitstreams: 1 DinaLOA.pdf: 757673 bytes, checksum: dfcacad0b099f951e69bc556d1a78317 (MD5) Previous issue date: 2009-08-20 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / Investigamos nesta pesquisa, o papel das rotas e da obten??o de informa??es sobre a efici?ncia no forrageio de Dinoponera quadriceps. Foram observadas duas col?nias numa ?rea de mata atl?ntica secund?ria na FLONA-ICMBio de N?sia Floresta, Estado do Rio Grande do Norte, pelo menos uma vez por semana. Inicialmente, observamos as oper?rias, desde a sa?da do ninho at? o retorno, sem qualquer tipo de manipula??o, numa segunda fase, introduzimos uma placa de acr?lico (100 x 30 x 0,8 cm) diante da entrada observada. Todo o registro comportamental foi feito com a t?cnica do focal time sampling e todas as ocorr?ncias, como complementar; os focais eram de 15 min, com registro a cada minuto, e intervalo de 5 min entre eles. As oper?rias gastaram a maior parte do tempo fora do ninho no comportamento de forrageio. O tempo fora do ninho e a dist?ncia percorrido mostra uma rela??o positiva. Estas vari?veis influenciaram na propor??o do alimento, que requereu mais tempo e dist?ncia na busca. A propor??o tamb?m interferiu no tempo que a oper?ria ficava no ninho antes de uma nova viagem, maior propor??o menor tempo no ninho. Durante toda a pesquisa, as oper?rias individuais demonstraram fidelidade ? rota e a setores na ?rea de uso, mesmo na presen?a da placa, na qual elas desviavam e continuavam seu curso. As caracter?sticas no forrageio quanto ao tempo, dist?ncia, rota fixa e flexibilidade para desviar de obst?culos, apresentadas pelas oper?rias indicam que as decis?es ocorrem em n?vel individual e ? eficiente em rela??o ao balan?o custo-benef?cio. A estrat?gia adotada se encaixa na teoria do ponto central e no teorema do valor marginal, e demonstra ser flex?vel ? presen?a de informa??es novas, o que indica que as oper?rias s?o capazes de aprender novas pistas do ambiente para orient?-las / In this study, we investigated the role of routes and information attainment for the queenless ant species Dinoponera quadriceps foraging efficiency. Two queenless ant colonies were observed in an area of Atlantic secondary Forest at the FLONA-ICMBio of Nisia Floresta, in the state of Rio Grande do Norte, northeastern Brazil, at least once a week. In the first stage of the study, we observed the workers, from leaving until returning to the colony. In the second stage, we introduced a acrylic plate (100 x 30 x 0,8 cm) on a selected entrance of the nest early in the morning before the ants left the nest. All behavioral recordings were done through focal time and all occurence samplings. The recording windows were of 15 minutes with 1 minute interval, and 5 minute intervals between each observation window. Foraging was the main activity when the workers were outside the nest. There was a positive correlation between time outside the nest and distance travelled by the ants. These variables influenced the proportion of resource that was taken to the nest, that is, the bigger its proportion, the longer the time outside and distance travelled during the search. That proportion also influenced the time the worker remained in the nest before a new trip, the bigger the proportion of the item, the shorter was the time in the nest. During all the study, workers showed fidelity to the route and to the sectors in the home range, even when the screen was in the ant?s way, once they deviated and kept the route. The features of foraging concerning time, distance, route and flexibility to go astray by the workers indicate that decisions are made by each individual and are optimal in terms of a cost-benefit relation. The strategy chosen by queenless ants fits the central place foraging and marginal value theorem theories and demonstrate its flexibility to new informations. This indicates that the workers can learn new environmental landmarks to guide their routes