A anandamida, um dos principais endocanabinóides estudados, além de se ligar aos receptores CB1, em altas doses, também é capaz de ativar os receptores vanilóides de potencial transitório tipo-1 (TRPV1). Evidências experimentais indicam que a sinalização mediada por CB1 facilita, enquanto TRPV1 prejudica, a resposta de adaptação a situações de estresse, tornando o animal mais susceptível a suas consequências comportamentais. Estudos demonstram que a inibição da enzima amida hidrolase de ácidos graxos (FAAH), responsável pela hidrólise da anandamida, apresenta efeito tipo-antidepressivo, efeito este também observado quando administrado antagonista de TRPV1. Portanto, a ação combinada de inibição da FAAH e bloqueio de TRPV1 poderia ter potencial efeito antidepressivo. Diante destas evidências, o objetivo do presente trabalho foi investigar se a administração sistêmica de AA-5HT, droga que inibe a FAAH e bloqueia TRPV1, em camundongos submetidos ao teste do nado forçado, promove um efeito tipo-antidepressivo; e ainda, se esse comportamento estaria relacionado com a ativação de receptores canabinóides CB1 e com bloqueio dos receptores vanilóides TRPV1. Camundongos Swiss machos receberam injeção intraperitoneal de AA-5HT (0.1, 0.3, e 1 mg/kg), inibidor da FAAH (URB597 - 0.03, 0.1, 0.3, 1, e 3 mg/kg), antagonista TRPV1 (SB366791 - 0.03, 0.1, 0.3, 1 e 3 mg/kg) e antagonista CB1 (AM251 - 1 e 3 mg/kg) ou o veículo correspondente e, 30 minutos depois, os mesmos animais foram submetidos ao teste do campo aberto. Imediatamente após foram submetidos ao teste do nado forçado. O tratamento com AA-5HT na dose de 0.3mg/kg reduziu significativamente o tempo de imobilidade no teste do nado forçado, sem alterar a atividade locomotora. Por outro lado, as doses testadas de URB597, SB366791 e AM251 não reduziram significativamente o tempo de imobilidade quando comparadas ao grupo veículo. E ainda, não foi observada somação de efeito da coadministração de doses equipotentes e subefetivas de SB366791 e URB597 no teste do nado forçado. Por fim, a pré-administração do antagonista CB1 (AM251) não alterou o tempo de imobilidade de AA-5HT. Apesar disso, quando o AA-5HT foi pré-administrado com o veículo utilizado para diluir o AM251, apresentou aumento significativo no tempo de imobilidade quando comparado aos animais pré-tratados com salina, comprometendo assim a investigação sobre a participação dos receptores CB1 no efeito do AA-5HT. Sendo assim, nossos resultados sugerem que a administração sistêmica de AA-5HT produz um efeito tipo-antidepressivo no teste do nado forçado. Entretanto, mais estudos são necessários para avaliar o envolvimento dos receptores CB1 neste comportamento. / Anandamide, one of the most studied endocannabinoids, acts through interaction with CB1 cannabinoids receptors, and, in higher doses, activate TRPV1 receptor. Experimental evidence shows that CB1-mediated signaling improve, while TRPV1-signaling impairs the adaptative response to stressful situations, thus increasing the susceptibility to behavioral consequences. The administration of inhibitors of fatty acid amide hydrolase (FAAH), responsible for anandamide hydrolysis, exerts antidepressant-like effects in preclinical models. The same effect is observed when TRPV1 antagonist is administered. Therefore, the combined blockade of FAAH and TRPV1 could potentially represent an interesting pharmacological tool to induce antidepressant effects. Based on that, the aim of this study was to investigate if AA-5HT, a FAAH inhibitor and TRPV1 blocker, would induce antidepressant-like effect in mice, and to evaluate the participation of TRPV1 and CB1 receptors in this effect. Male Swiss mice received an intraperitoneal injection of AA-5HT (0.1, 0.3, e 1 mg/kg), FAAH inhibitor (URB597 - 0.03, 0.1, 0.3, 1, e 3 mg/kg), TRPV1 antagonist (SB366791 - 0.03, 0.1, 0.3, 1 e 3 mg/kg) and CB1 antagonist (AM251 - 1 e 3 mg/kg) or the corresponding vehicle and, 30 minutes later, they were individually submitted to the open field test. Immediately after this, the same animal was submitted to the forced swimming test. Our results showed that the treatment with AA-5HT at dose 0,3mg/kg significantly reduced the immobility time in the forced swim test without changing the locomotor activity. On the other hand, the tested dose range of URB597, SB366791 e AM251 did not significantly reduced the immobility time when compared to vehicle group. Furthermore, there was no observed effect of the coadministration of equipotent and sub-effective doses of SB366791 and URB597 on forced swim test. Finally, pre-administration of the CB1 antagonist (AM251) did not alter the immobility time of AA-5HT. However, when AA-5HT was pre-administered with the vehicle used to dilute AM251, it showed a significant increase in immobility time when compared to animals pretreated with saline, thus compromising the study about the participation of CB1 receptors in the effect of AA-5HT. Thus, our results suggest systemic administration of AA-5HT produces an antidepressant-like effect on FST. However, further studies are needed to evaluate the involvement of CB1 receptors in this behavior.

INTRODUÇÃO: No treinamento combinado (TC), a realização do treinamento aeróbio (TA) pode reduzir os ganhos de força e/ou potência decorrentes do treinamento de força (TF) quando ambos são realizados simultaneamente (efeito da interferência). O tipo de exercício aeróbio do TC tem sido investigado como possível fator determinante do efeito da interferência, porém não se sabe os efeitos do TC de força e natação na força muscular (FM). OBJETIVO: Analisar os efeitos do TF, treinamento de natação (TN) e TC de força e natação nas adaptações de FM, cardiorrespiratórias e desempenho de nado em adultos. MATERIAIS E MÉTODOS: 38 sujeitos de ambos os sexos foram randomicamente divididos nas condições TF (n=13; 29,5 ± 10,5 anos), TN (n=14; 30,71 ± 9,38 anos) e TC (n=11; 34,5 ± 9,8 anos). Destes, 14 participantes (29,2 ± 8,6 anos) realizaram um período controle (CON) de quatro semanas, previamente ao início do treinamento. O treinamento foi realizado três vezes por semana, durante 12 semanas. As avaliações da FM, aptidão cardiorrespiratória e desempenho de nado foram realizadas antes da condição CON (PRÉ-4), após condição CON/antes do treinamento (PRÉ0) e após treinamento (PÓS). As cargas do TF e volumes do TN entre os mesociclos de treinamento também foram comparados. Para a análise estatística foram utilizados procedimentos descritivos (média e desvio padrão) e teste de modelos mistos generalizados (GMM). RESULTADOS: Foi observado aumento significante (p<0,05) em todas as condições, sem diferença entre elas, para as variáveis de força dinâmica máxima (RM) de extensão de joelho (FMEJ), de extensão de cotovelo (FMEC) e resistência muscular localizada (RML) de extensão de cotovelos (RMLEC). Para as variáveis de RMLEJ e RM de extensão de ombro (FMEO) o aumento ocorreu apenas nas condições TF e TC, enquanto que a RML de extensão de ombro (RMLEO) só aumentou para o TN. Para a força isométrica, somente a força isométrica máxima de extensão de ombro, amentou significativamente nas condições TF e TC. A potência máxima em cicloergômetro aumentou apenas para o TF. As demais variáveis cardiorrespiratórias não se modificaram, com nenhum dos tipos de treinamento. Os tempos diminuíram e as velocidades de nado aumentaram em todas as distâncias, bem como a frequência de braçada (FB) nos 50 e 100 m e o índice de nado (IN) em 25 m aumentaram significativamente (p<0,05) para TC e TN, sem diferença entre as condições e nos 100 m o aumento ocorreu somente para o TC. Tanto no TN quanto no TF houve aumento significativo (p<0,05) dos volumes e cargas, respectivamente, entre os mesociclos, sem diferença entre as condições. CONCLUSÕES: Não há efeito da interferência nos ganhos de FM com o TC de força e natação. As variáveis cardiorrespiratórias não foram influenciadas por nenhum dos tipos de treino, porém aspectos relacionados à especificidade da medida podem ter afetado os resultados. A realização do TF associado a um TN parece não melhorar o desempenho de nado quando comparado ao TN isolado, em indivíduos adultos previamente destreinados. / INTRODUCTION: In combined training (CT), aerobic training (AT) can reduce strength and/or power gains resulting from strength training (ST) when both are simultaneously performed (interference effect). The type of aerobic exercise of the CT has been investigated as a possible determining factor of the interference effect, however the effects of the combined strength and swimming training on muscle strength (MS) are not known. OBJECTIVE: To analyze ST, swimming training (SW) and combined strength and swimming training effects on MS, cardiorespiratory and swimming performance adaptations in adults. MATERIALS AND METHODS: 38 subjects of both sexes were randomly divided into ST (n=13; 29.5 ± 10.5 years old), SW (n=14; 30.71 ± 9.38 years old) and CT (n=11; 34.5 ± 9.8 years old) conditions. Of them, 14 participants (29.2 ± 8.6 years old) performed a control period (COM) of four weeks, previously to the beginning of the training. The training was performed three times a week during 12 weeks. MS, cardiorespiratory fitness and swimming performance assessments were performed before CON condition (PRE-4), after CON condition/before training (PRE0) and after training (POST). ST loads and SW volumes between the training mesocycles were also compared. For statistical analysis, descriptive procedures (mean and standard deviation) and generalized mixed models (GMM) were used. RESULTS: a significant increase in all conditions were observed (p<0.05), without difference between them, for maximal dynamic strength (RM) of knee extension (RMKE), elbow extension (RMEE) and local muscular resistance (LMR) of elbow extension (LMREE) outcomes. For LMRKE and RM of shoulder extension (RMSE) outcomes, the increase only occurred in ST and CT conditions, whereas LMR of knee extension (LMRKE) only increased for SW. For isometric strength, only maximal isometric strength of knee extension significantly increased in ST and CT conditions. Maximal power in cycle ergometer only increased for ST. The other cardiorespiratory variables were not modified, with none of the training types. Swimming times decreased and swimming speeds increased in all distances, as well as stroke frequency (SF) in 50 and 100 m and index of swimming (IS) in 25 m significantly increased (p<0.05) for CT and SW, without difference between conditions, and in 100 m the increase only occurred for CT. In both SW and ST there was a significant increase (p<0.05) of the volumes and loads, respectively, between the mesocycles, without difference between the conditions. CONCLUSIONS: There is not an interference effect in MS gains with combined strength and swimming training. Cardiorespiratory outcomes were not influenced by any of the training types; nevertheless, aspects related to measurement specificity could have affected the results. The performance of ST associated to a SW does not seem to improve swimming performance when compared to isolated SW, in previously untrained adult individuals.

Exposição a estressores incontroláveis leva a mudanças comportamentais e neuroquímicas, que têm sido associadas ao mau funcionamento da via Núcleo Mediano da Rafe (NMnR) Hipocampo Dorsal (HD). Estas mudanças comportamentais podem ser atenuadas por injeções intra hipocampais de NMDA ou de agonistas 5-HT1a. Ativação de receptores NMDA (NMDAr) aumentam os níveis de serotonina tanto no NMnR quanto no HD. Neste trabalho, nosso obejtivo foi analisar, em animais expostos ao Teste do nado forçado, se a ativação ou bloqueio dos receptores NMDA antes da exposição ao agente estressor ou 24 horas após essa exposição podem prevenir ou atenuar os efeitos do estresse. Ratos Wistar machos receberam duas injeções intra-NMnR de Salina (Sal), NMDA (1nmoles/0,2µL; agonista NMDAr) e/ou AP-7 (3nmoles/0,2µL; antagonista NMDAr) compondo os grupos experimentais: Sal+Sal, Sal+NMDA, AP-7+Sal, AP-7+NMDA. As drogas foram administradas em dois grupos experimentais, antes da pré-exposição ao nado forçado ou 24 horas após a pré-exposição e antes do teste. Foram analisados o tempo de latência para o primeiro episódio de imobilidade e o tempo total de imobilidade. A análise dos resultados mostrou que a administração de AP-7 antes da pré-exposição ou antes do teste e a administração de NMDA antes do teste, atenuaram os efeitos comportamentais causados pelo estresse, mostrando o envolvimento desses receptores nos mecanismos de adaptação a eventos aversivo e também que o momento no qual ocorre a intervenção farmacológica influencia essa adaptação. / Exposure to uncontrollable stressors leads to behavioral and neurochemical changes, which has been associated to mal functioning of the Median Raphe Nucleus (MnRN)-Dorsal Hippocampus (DH) serotoninergic pathway. These deficits can be attenuated by intra-hippocampal injections of NMDA antagonists or 5-HT1a agonists. Activation of MnRN glutamatergic NMDA receptors (NMDAr) increases serotonin release in both MnRN and DH. We previously showed that MnRN injections of NMDA (NMDAr agonist) and/or AP7 (NMDAr antagonist) after pre-test attenuated total time spent immobile in the forced swim test (FST). In this study we used the forced swim test to investigated whether activation and/or blockade of MnRN NMDAr before exposure to swim stress or 24 hours after the exposure, could prevent the effects of this stressor. Rats with cannulas aimed to the MnRN received two intracerebral injections (0.2µl each) of Saline (Sal), AP7 (3nmols) and/or NMDA (1nmol)(5 min interval), administered as follows: Sal+Sal, Sal+NMDA, AP7+Sal and AP7+NMDA. The animals were forced to swim for 15 min and 24 hrs later rats were re-exposed to FST One group received the treatment before exposure to stress and another group received it 24 hrs later, right before the test. Latency to display immobility and total time spent immobile were registered. After test, all animals were sacrificed under deep anesthesia, perfused and had their brains removed for histological analysis to confirm site of injection. Only animals who had their sites of injection confirmed were used in the analysis (ONEWAY ANOVA/Tukey test). Our data suggest that blockade of glutamatergic neurotransmission in the MnRN before exposure and 24 hrs later, and activation of this transmission 24 hrs later to stress prevents the behavioral consequences of forced swim stress.

No description available.

Voluntary wheel running is rewarding and believed to activate the same brain reward system as in alcohol and drug addiction. Brain-derived neurotrophic factor (BDNF), a well-known growth factor widely expressed in the brain, is modulated by both voluntary exercise and alcohol consumption. The aim of this study was to evaluate how voluntary exercise affects the expression levels of BDNF and its receptor TrkB in brain regions involved in positive and negative reinforcement. Additionally we wanted to evaluate the effect it may have on alcohol drinking behaviors in C57BL/6 mice, a mouse model which are naturally prone for engaging in voluntary exercise and voluntary alcohol consumption. We found a small upregulation in DG and CA1 after three weeks of exercise, confirming findings by others, and a significant 3-fold downregulation of BDNF in NAc after both three weeks of exercise and exercise followed by a five week period of either ethanol intake or not. Interestingly, we here show a significant 100-fold increase in BDNF after exercise and a 120-fold increase after both exercise and alcohol consumption in amygdala, a region involved in regulation of anxiety-related behavior and negative reinforcement. Additionally a slightly lower 10-fold increase in BDNF was seen after exercise and a 15-fold increase after exercise followed by ethanol in prefrontal cortex, a structure contributing to reward-related behavior. Behaviorally, we could not either directly following exercise or at five weeks post-exercise detect any significant effect of wheel-running on depression-related behavior. However, we did find that exercise significantly increased the alcohol intake.

Guidelines for sustainable swim-with tourism for large whales are not welldeveloped, as researchers have focused on delphinids. Nations that signed the Convention on Biological Diversity at the Earth Summit in Rio de Janeiro in 1992 are obligated to consider sustainable use principles when allowing new ecotourism activities, yet the fast-growing worldwide swim-with-whales industry is lacking the research needed to create successful management guidelines that can be implemented by local communities. From September to November of 2005 and July to October of 2006, I collected movement and behavioral state data for southern right whales in proximity of swimmers at Península Valdés, Argentina. Whales were observed before, during, and after a series of directed interactions with swimmers. I quantified the behavioral and movement effects relative to group composition of whales (mother/calf pairs, juveniles or adult/mixed groups) and activity level of swimmers. Group composition had a significant effect on the response of whales to swimmers. Swimmer activity level did not substantially affect the reaction of whales. Resting and socializing activities significantly decreased and traveling activities significantly increased when boats approached and when swimmers entered the water. Resting and socializing bout length in the presence of swimmers decreased to less than a third of the length of bouts when swimmers were not present. Whales swam faster, reoriented more often, and followed a less linear path during interactions. Effects were greater for mother/calf pairs than juveniles, while mixed adult/juvenile groups showed no significant changes in behavior or movement. The initial reaction of whales to the approach of the boat and the entry of swimmers into the water was a good predictor of the magnitude of effects on the behavior and movement patterns of the whale. Increased levels of activity are a concern for the whales that are resting and not feeding in this area. To provide quality resource management guidelines for this activity, additional research is needed to determine long-term effects of boat and swimmer activities on the behavior of whales. It is also important to obtain energetic data for right whales to determine the magnitude of impacts.

No description available.

Selenium (Se) is known to cause chronic toxicity in aquatic species. In particular, dietary exposure of fish to selenomethionine (SeMet), the primary form of Se in the diet, is of concern. Previous studies reported that chronic exposure to elevated dietary SeMet altered swimming performance, aerobic metabolism, and energy and endocrine homeostasis in adult fish. However, little is known about the direct effects of dietary SeMet exposure in juvenile fish. Therefore, the overall objective of this thesis was to investigate sublethal pathophysiological effects of subchronic dietary SeMet exposure in two juvenile fish species, fathead minnow (Pimephales promelas) and rainbow trout (Oncorhynchus mykiss). In the first experiment, 20 days post hatch (dph) juvenile fathead minnow were exposed to different measured concentrations (2.8, 5.4, 9.9, 26.5 µg Se/g dry mass [dm]) of Se in food in the form of SeMet for 60 days. In the second experiment, 14 dph juvenile rainbow trout were exposed for 37 days to different measured concentrations (1.0, 4.1, 11.2, 26.1 µg Se/g dm) of Se in food in the form of SeMet. Following exposure, samples were collected for Se analysis and fish were subjected to a swimming performance challenge to assess critical swim speed (Ucrit), tail beat frequency and tail beat amplitude, oxygen consumption (MO2), cost of transport (COT), standard metabolic rate (SMR), active metabolic rate (AMR), and factorial aerobic scope (F-AS). Dietary SeMet exposure impaired swimming ability in both fathead minnow and rainbow trout. Juvenile fathead minnow showed alterations in aerobic metabolism with increased MO2, COT and AMR at the 9.9 and 26.5 µg Se/g diets, while dietary SeMet exposure did not appear to affect aerobic metabolism in juvenile rainbow trout. After swim performance experiments, swam fish were considered fatigued and metabolic and energy storage endpoints were compared to non-swam (non-fatigued) fish. Energy storage capacity was measured via whole body (fathead minnow) and liver and muscle (rainbow trout) triglyceride and glycogen concentrations. For fathead minnow, triglyceride concentrations in non-swam fish were significantly elevated in the 5.4 µg Se/g group relative to controls, and swam fish had significantly lower whole body triglycerides than non-swam fish. All non-swam SeMet exposure groups had significantly decreased whole body glycogen concentrations compared to controls while the 5.4 and 26.5 µg Se/g exposure groups had significantly greater whole body glycogen concentrations in swam versus non-swam fish. In juvenile rainbow trout, liver triglyceride concentrations were significantly lower in all SeMet exposed groups compared to controls in non-swam fish. Swimming decreased liver and muscle triglycerides in the control and 11.2 µg Se/g treatment groups. Liver glycogen concentrations were greater in swam trout in the 4.1 µg Se/g dm exposure group. Muscle glycogen concentrations in non-swam fish, were significantly decreased in the 4.1 and 11.2 µg Se/g exposed groups compared to controls, while muscle glycogen in swam fish was unaffected by dietary SeMet exposure. For the swim status factor, muscle glycogen concentrations were significantly greater in swam versus non-swam trout in all treatment groups. Therefore, dietary SeMet exposure caused impaired swimming performance and metabolic alterations in both juvenile fathead minnow and juvenile rainbow trout. Species differences were apparent, especially in the patterns of altered energy status between swam and non-swam fish exposed to Se. Overall, the pathophysiological implications of these sublethal effects are unclear, but suggest that dietary SeMet exposure may negatively influence juvenile fish survivability in natural habitats.

INTRODUÇÃO: No treinamento combinado (TC), a realização do treinamento aeróbio (TA) pode reduzir os ganhos de força e/ou potência decorrentes do treinamento de força (TF) quando ambos são realizados simultaneamente (efeito da interferência). O tipo de exercício aeróbio do TC tem sido investigado como possível fator determinante do efeito da interferência, porém não se sabe os efeitos do TC de força e natação na força muscular (FM). OBJETIVO: Analisar os efeitos do TF, treinamento de natação (TN) e TC de força e natação nas adaptações de FM, cardiorrespiratórias e desempenho de nado em adultos. MATERIAIS E MÉTODOS: 38 sujeitos de ambos os sexos foram randomicamente divididos nas condições TF (n=13; 29,5 ± 10,5 anos), TN (n=14; 30,71 ± 9,38 anos) e TC (n=11; 34,5 ± 9,8 anos). Destes, 14 participantes (29,2 ± 8,6 anos) realizaram um período controle (CON) de quatro semanas, previamente ao início do treinamento. O treinamento foi realizado três vezes por semana, durante 12 semanas. As avaliações da FM, aptidão cardiorrespiratória e desempenho de nado foram realizadas antes da condição CON (PRÉ-4), após condição CON/antes do treinamento (PRÉ0) e após treinamento (PÓS). As cargas do TF e volumes do TN entre os mesociclos de treinamento também foram comparados. Para a análise estatística foram utilizados procedimentos descritivos (média e desvio padrão) e teste de modelos mistos generalizados (GMM). RESULTADOS: Foi observado aumento significante (p<0,05) em todas as condições, sem diferença entre elas, para as variáveis de força dinâmica máxima (RM) de extensão de joelho (FMEJ), de extensão de cotovelo (FMEC) e resistência muscular localizada (RML) de extensão de cotovelos (RMLEC). Para as variáveis de RMLEJ e RM de extensão de ombro (FMEO) o aumento ocorreu apenas nas condições TF e TC, enquanto que a RML de extensão de ombro (RMLEO) só aumentou para o TN. Para a força isométrica, somente a força isométrica máxima de extensão de ombro, amentou significativamente nas condições TF e TC. A potência máxima em cicloergômetro aumentou apenas para o TF. As demais variáveis cardiorrespiratórias não se modificaram, com nenhum dos tipos de treinamento. Os tempos diminuíram e as velocidades de nado aumentaram em todas as distâncias, bem como a frequência de braçada (FB) nos 50 e 100 m e o índice de nado (IN) em 25 m aumentaram significativamente (p<0,05) para TC e TN, sem diferença entre as condições e nos 100 m o aumento ocorreu somente para o TC. Tanto no TN quanto no TF houve aumento significativo (p<0,05) dos volumes e cargas, respectivamente, entre os mesociclos, sem diferença entre as condições. CONCLUSÕES: Não há efeito da interferência nos ganhos de FM com o TC de força e natação. As variáveis cardiorrespiratórias não foram influenciadas por nenhum dos tipos de treino, porém aspectos relacionados à especificidade da medida podem ter afetado os resultados. A realização do TF associado a um TN parece não melhorar o desempenho de nado quando comparado ao TN isolado, em indivíduos adultos previamente destreinados. / INTRODUCTION: In combined training (CT), aerobic training (AT) can reduce strength and/or power gains resulting from strength training (ST) when both are simultaneously performed (interference effect). The type of aerobic exercise of the CT has been investigated as a possible determining factor of the interference effect, however the effects of the combined strength and swimming training on muscle strength (MS) are not known. OBJECTIVE: To analyze ST, swimming training (SW) and combined strength and swimming training effects on MS, cardiorespiratory and swimming performance adaptations in adults. MATERIALS AND METHODS: 38 subjects of both sexes were randomly divided into ST (n=13; 29.5 ± 10.5 years old), SW (n=14; 30.71 ± 9.38 years old) and CT (n=11; 34.5 ± 9.8 years old) conditions. Of them, 14 participants (29.2 ± 8.6 years old) performed a control period (COM) of four weeks, previously to the beginning of the training. The training was performed three times a week during 12 weeks. MS, cardiorespiratory fitness and swimming performance assessments were performed before CON condition (PRE-4), after CON condition/before training (PRE0) and after training (POST). ST loads and SW volumes between the training mesocycles were also compared. For statistical analysis, descriptive procedures (mean and standard deviation) and generalized mixed models (GMM) were used. RESULTS: a significant increase in all conditions were observed (p<0.05), without difference between them, for maximal dynamic strength (RM) of knee extension (RMKE), elbow extension (RMEE) and local muscular resistance (LMR) of elbow extension (LMREE) outcomes. For LMRKE and RM of shoulder extension (RMSE) outcomes, the increase only occurred in ST and CT conditions, whereas LMR of knee extension (LMRKE) only increased for SW. For isometric strength, only maximal isometric strength of knee extension significantly increased in ST and CT conditions. Maximal power in cycle ergometer only increased for ST. The other cardiorespiratory variables were not modified, with none of the training types. Swimming times decreased and swimming speeds increased in all distances, as well as stroke frequency (SF) in 50 and 100 m and index of swimming (IS) in 25 m significantly increased (p<0.05) for CT and SW, without difference between conditions, and in 100 m the increase only occurred for CT. In both SW and ST there was a significant increase (p<0.05) of the volumes and loads, respectively, between the mesocycles, without difference between the conditions. CONCLUSIONS: There is not an interference effect in MS gains with combined strength and swimming training. Cardiorespiratory outcomes were not influenced by any of the training types; nevertheless, aspects related to measurement specificity could have affected the results. The performance of ST associated to a SW does not seem to improve swimming performance when compared to isolated SW, in previously untrained adult individuals.

INTRODUÇÃO: No treinamento combinado (TC), a realização do treinamento aeróbio (TA) pode reduzir os ganhos de força e/ou potência decorrentes do treinamento de força (TF) quando ambos são realizados simultaneamente (efeito da interferência). O tipo de exercício aeróbio do TC tem sido investigado como possível fator determinante do efeito da interferência, porém não se sabe os efeitos do TC de força e natação na força muscular (FM). OBJETIVO: Analisar os efeitos do TF, treinamento de natação (TN) e TC de força e natação nas adaptações de FM, cardiorrespiratórias e desempenho de nado em adultos. MATERIAIS E MÉTODOS: 38 sujeitos de ambos os sexos foram randomicamente divididos nas condições TF (n=13; 29,5 ± 10,5 anos), TN (n=14; 30,71 ± 9,38 anos) e TC (n=11; 34,5 ± 9,8 anos). Destes, 14 participantes (29,2 ± 8,6 anos) realizaram um período controle (CON) de quatro semanas, previamente ao início do treinamento. O treinamento foi realizado três vezes por semana, durante 12 semanas. As avaliações da FM, aptidão cardiorrespiratória e desempenho de nado foram realizadas antes da condição CON (PRÉ-4), após condição CON/antes do treinamento (PRÉ0) e após treinamento (PÓS). As cargas do TF e volumes do TN entre os mesociclos de treinamento também foram comparados. Para a análise estatística foram utilizados procedimentos descritivos (média e desvio padrão) e teste de modelos mistos generalizados (GMM). RESULTADOS: Foi observado aumento significante (p<0,05) em todas as condições, sem diferença entre elas, para as variáveis de força dinâmica máxima (RM) de extensão de joelho (FMEJ), de extensão de cotovelo (FMEC) e resistência muscular localizada (RML) de extensão de cotovelos (RMLEC). Para as variáveis de RMLEJ e RM de extensão de ombro (FMEO) o aumento ocorreu apenas nas condições TF e TC, enquanto que a RML de extensão de ombro (RMLEO) só aumentou para o TN. Para a força isométrica, somente a força isométrica máxima de extensão de ombro, amentou significativamente nas condições TF e TC. A potência máxima em cicloergômetro aumentou apenas para o TF. As demais variáveis cardiorrespiratórias não se modificaram, com nenhum dos tipos de treinamento. Os tempos diminuíram e as velocidades de nado aumentaram em todas as distâncias, bem como a frequência de braçada (FB) nos 50 e 100 m e o índice de nado (IN) em 25 m aumentaram significativamente (p<0,05) para TC e TN, sem diferença entre as condições e nos 100 m o aumento ocorreu somente para o TC. Tanto no TN quanto no TF houve aumento significativo (p<0,05) dos volumes e cargas, respectivamente, entre os mesociclos, sem diferença entre as condições. CONCLUSÕES: Não há efeito da interferência nos ganhos de FM com o TC de força e natação. As variáveis cardiorrespiratórias não foram influenciadas por nenhum dos tipos de treino, porém aspectos relacionados à especificidade da medida podem ter afetado os resultados. A realização do TF associado a um TN parece não melhorar o desempenho de nado quando comparado ao TN isolado, em indivíduos adultos previamente destreinados. / INTRODUCTION: In combined training (CT), aerobic training (AT) can reduce strength and/or power gains resulting from strength training (ST) when both are simultaneously performed (interference effect). The type of aerobic exercise of the CT has been investigated as a possible determining factor of the interference effect, however the effects of the combined strength and swimming training on muscle strength (MS) are not known. OBJECTIVE: To analyze ST, swimming training (SW) and combined strength and swimming training effects on MS, cardiorespiratory and swimming performance adaptations in adults. MATERIALS AND METHODS: 38 subjects of both sexes were randomly divided into ST (n=13; 29.5 ± 10.5 years old), SW (n=14; 30.71 ± 9.38 years old) and CT (n=11; 34.5 ± 9.8 years old) conditions. Of them, 14 participants (29.2 ± 8.6 years old) performed a control period (COM) of four weeks, previously to the beginning of the training. The training was performed three times a week during 12 weeks. MS, cardiorespiratory fitness and swimming performance assessments were performed before CON condition (PRE-4), after CON condition/before training (PRE0) and after training (POST). ST loads and SW volumes between the training mesocycles were also compared. For statistical analysis, descriptive procedures (mean and standard deviation) and generalized mixed models (GMM) were used. RESULTS: a significant increase in all conditions were observed (p<0.05), without difference between them, for maximal dynamic strength (RM) of knee extension (RMKE), elbow extension (RMEE) and local muscular resistance (LMR) of elbow extension (LMREE) outcomes. For LMRKE and RM of shoulder extension (RMSE) outcomes, the increase only occurred in ST and CT conditions, whereas LMR of knee extension (LMRKE) only increased for SW. For isometric strength, only maximal isometric strength of knee extension significantly increased in ST and CT conditions. Maximal power in cycle ergometer only increased for ST. The other cardiorespiratory variables were not modified, with none of the training types. Swimming times decreased and swimming speeds increased in all distances, as well as stroke frequency (SF) in 50 and 100 m and index of swimming (IS) in 25 m significantly increased (p<0.05) for CT and SW, without difference between conditions, and in 100 m the increase only occurred for CT. In both SW and ST there was a significant increase (p<0.05) of the volumes and loads, respectively, between the mesocycles, without difference between the conditions. CONCLUSIONS: There is not an interference effect in MS gains with combined strength and swimming training. Cardiorespiratory outcomes were not influenced by any of the training types; nevertheless, aspects related to measurement specificity could have affected the results. The performance of ST associated to a SW does not seem to improve swimming performance when compared to isolated SW, in previously untrained adult individuals.