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1.
Mar Pollut Bull ; 160: 111680, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33181953

RESUMO

Anthropogenic sound can affect fish behaviour and physiology which may affect their well-being. However, it remains a major challenge to translate such effects to consequences for fitness at an individual and population level. For this, energy budget models have been developed, but suitable data to parametrize these models are lacking. A first step towards such parametrization concerns the objective quantification of behavioural states at high resolution. We experimentally exposed individual Atlantic cod (Gadus morhua) in a net pen to the playback of seismic airgun sounds. We demonstrated that individual cod in the net pen did not change their swimming patterns immediately at the onset of the sound exposure. However, several individuals changed their time spent in three different behavioural states during the 1 h exposure. This may be translated to changes in energy expenditure and provide suitable input for energy budget models that allow predictions about fitness and population consequences.


Assuntos
Gadus morhua , Animais , Comportamento Animal , Metabolismo Energético , Humanos , Som , Natação
2.
Nat Commun ; 11(1): 5408, 2020 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-33106484

RESUMO

It has long been proposed that flying and swimming animals could exploit neighbour-induced flows. Despite this it is still not clear whether, and if so how, schooling fish coordinate their movement to benefit from the vortices shed by others. To address this we developed bio-mimetic fish-like robots which allow us to measure directly the energy consumption associated with swimming together in pairs (the most common natural configuration in schooling fish). We find that followers, in any relative position to a near-neighbour, could obtain hydrodynamic benefits if they exhibit a tailbeat phase difference that varies linearly with front-back distance, a strategy we term 'vortex phase matching'. Experiments with pairs of freely-swimming fish reveal that followers exhibit this strategy, and that doing so requires neither a functioning visual nor lateral line system. Our results are consistent with the hypothesis that fish typically, but not exclusively, use vortex phase matching to save energy.


Assuntos
Peixes/fisiologia , Animais , Fenômenos Biomecânicos , Biomimética , Hidrodinâmica , Sistema da Linha Lateral/química , Sistema da Linha Lateral/fisiologia , Robótica , Natação
3.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 4620-4623, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33019023

RESUMO

Wearable body area networks (BANs) have been widely used in activity measurements for kinematic information collection. This paper presents the design and implementation of a wearable device used as a training tool in freestyle swimming. The device supplies a close-loop control mechanism via a fuzzy logic controller. Swimming posture data is collected quantitatively and audibly fed back to swimmers in real time through bone conductors. Two recreational swimmers were invited to participate in a series of experiments including 7 days of baseline capability test (no feedback), 7 days of feedback training, and 2 days of retention test. It was found that both swimmers could well adapt to the feedback instructions. A maximum of 7.62% of lap time improvement and 29.64% of trunk roll improvement were observed in FB training, and such pattern was maintained after feedback was removed. We conclude that real-time fuzzy logic feedback can be used to improve recreational swimmers performance.


Assuntos
Lógica Fuzzy , Natação , Biorretroalimentação Psicológica , Retroalimentação , Humanos , Postura
4.
Artigo em Inglês | MEDLINE | ID: mdl-32867383

RESUMO

BACKGROUND AND AIM: To identify kinematic variables related to short course 100 m breaststroke performance. METHODS: An automatic race analysis system was utilized to obtain start (0-15 m), turn (5 m before the wall until 10 m out), finish (95-100 m), and clean swimming (the rest of the race) segment times as well as cycle rate and cycle length during each swimming cycle from 15 male swimmers during a 100 m breaststroke race. A bivariate correlation and a partial correlation were employed to assess the relationship between each variable and swimming time. RESULTS: Turns were the largest time contributor to the finishing time (44.30 ± 0.58%), followed by clean swimming (38.93 ± 0.50%), start (11.39 ± 0.22%), and finish (5.36 ± 0.18%). The finishing time was correlated (p < 0.001) with start segment time (r = 0.979), clean swimming time (r = 0.940), and 10 m turn-out time (r = 0.829). The clean swimming time was associated with the finishing time, but cycle rate and cycle length were not. In both start and turns, the peak velocity (i.e., take-off and push-off velocity) and the transition velocity were related to the segment time (r ≤ -0.673, p ≤ 0.006). CONCLUSIONS: Breaststroke training should focus on: (I) 15 m start with generating high take-off velocity, (II) improving clean swimming velocity by finding an optimal balance between cycle length and rate, (III) 10 m turn-out with maintaining a strong wall push-off, and (IV) establishing a high transition velocity from underwater to surface swimming.


Assuntos
Desempenho Atlético/fisiologia , Tempo de Reação/fisiologia , Natação/fisiologia , Desempenho Atlético/psicologia , Fenômenos Biomecânicos/fisiologia , Humanos , Manutenção , Masculino
5.
Aquat Toxicol ; 228: 105611, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32949974

RESUMO

Bifenthrin is a pyrethroid insecticide commonly used in agricultural and urban sectors, and is found in watersheds worldwide. As a sodium channel blocker, at sublethal concentrations it causes off-target effects, including disruption of calcium signaling and neuronal growth. At the whole organism level, sublethal concentrations of bifenthrin cause behavioral effects in fish species, raising concerns about the neurotoxic properties of the compound on fish populations. Here we describe the application of a high-throughput behavioral system to evaluate contaminant impacts on the sensitive early-life stages of Delta smelt (Hypomesus transpacificus), a critically endangered teleost species endemic to the San Francisco Bay Delta (SFBD), California, USA. Leveraging the natural behavior of early-larval Delta smelt, whereby they increase movement in bright light and decrease movement in the dark, we developed a test using a cycle of light and dark periods in a closed chamber to test hyper- or hypoactivity for this species. We show that early-larval Delta smelt have a significant preference to move toward light, and utilized the behavioral test to evaluate the impact of exposure to bifenthrin at concentrations found in habitats where Delta smelt reportedly spawn, ranging up to concentrations detected in tributaries to these habitats. All tested concentrations of bifenthrin (nominal 2, 10, or 100 ng/L) caused hyperactivity, over a 96 h exposure, with noted significance determined during the light period of the test. To further understand the impact of bifenthrin exposure, expression of a suite of genes relevant to neurodevelopment, the mechanistic target of rapamycin (mTOR) signaling pathway, and biotransformation in exposed larvae were also measured. Following exposure to picomolar concentrations of bifenthrin, expression of genes in the mTOR signaling and neurogenesis pathways were altered alongside behavior. This study demonstrates how light and dark cycle behavioral tests can be used to assess sensitive alterations in swimming activity in Delta smelt at early developmental stages and how gene expression can complement these assays. This approach can be used to assess the impact of multiple compounds that occur within the restricted habitat of Delta smelt, thus having the potential to greatly inform conservation management strategies for this critically sensitive life stage.


Assuntos
Espécies em Perigo de Extinção , Larva/efeitos dos fármacos , Atividade Motora/efeitos dos fármacos , Osmeriformes/crescimento & desenvolvimento , Piretrinas/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Relação Dose-Resposta a Droga , Ecossistema , Osmeriformes/fisiologia , Estações do Ano , Natação
6.
PLoS One ; 15(9): e0239627, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32997701

RESUMO

In spite of many decades of research, the spawning migration of the European eel Anguilla anguilla from the European coast to the Sargasso Sea remains a mystery. In particular, the role of the swimbladder as a buoyancy regulating structure is not yet understood. In this study, we exercised silver eels in a swim tunnel under elevated hydrostatic pressure. The transcriptome of gas gland tissue of these exercised eels was then compared to the known transcriptome of not exercised (control) silver eel gas gland cells. Due to the high infection rate of the eel population with the swimbladder parasite Anguillicola crassus, the comparison also included an exercised group of silver eels with a heavily damaged swimbladder, and we compared the previously published transcriptome of not exercised silver eels with a highly damaged swimbladder with the exercised group of silver eels with a heavily damaged swimbladder. The comparisons of unexercised (control) silver eels with exercised silver eels with functional swimbladder (EF), as well as with exercised silver eels with damaged swimbladder (ED), both showed a significant elevation in transcripts related to glycolytic enzymes. This could also be observed within the comparison of unexercised silver eels with a highly infected swimbladder with exercised eels with a damaged swimbladder (DED). In contrast to EF, in ED a significant elevation in transcript numbers of mitochondrial NADH dehydrogenase was observed. While in EF the transcriptional changes suggested that acid production and secretion was enhanced, in ED these changes appeared to be related to thickened tissue and thus elevated diffusion distances. The remarkable number of differentially expressed transcripts coding for proteins connected to cAMP-dependent signaling pathways indicated that metabolic control in gas gland cells includes cAMP-dependent pathways. In contrast to ED, in EF significant transcriptional changes could be related to the reconstruction of the extracellular matrix, while in ED tissue repair and inflammation was more pronounced. Surprisingly, in exercised eels hypoxia inducible transcription factor expression was elevated. In EF, a large number of genes related to the circadian clock were transcriptionally modified, which may be connected to the circadian vertical migrations observed during the spawning migration.


Assuntos
Sacos Aéreos/metabolismo , Enguias/metabolismo , Glândulas Exócrinas/metabolismo , Glicólise , Pressão Hidrostática , Migração Animal , Animais , Dióxido de Carbono/metabolismo , Enguias/fisiologia , Ácido Láctico/metabolismo , Natação , Transcriptoma
7.
Chemosphere ; 254: 126872, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32957284

RESUMO

The distribution of 20 personal care products (PCPs), including seven preservatives, six UV filters, five anticorrosion agents, and two antimicrobials, were determined in 40 swimming pools using solid phase extraction followed by liquid chromatography-tandem mass spectrometry. Among 14 targets detected, 1H-benzotriazole and triclocarban were observed in all samples. The detected concentrations of preservatives, UV filters, anticorrosion agents, and antimicrobials were in the ranges of not detected (nd)-179 ng L-1, nd-289 ng L-1, nd-58.4 ng L-1, and nd-56.9 ng L-1, respectively. The presence of preservatives, UV filters and antimicrobials in pool waters might be mainly brought in by human activities while anticorrosion agents were mainly from the source water. Furthermore, the concentrations of methylparaben, ethylparaben, 1H-benzotriazole, 5-methyl-1H-benzotriazole, 5-chloro-1H-benzotriazole, and 5,6-dimethyl-1H-benzotriazole in indoor pools were found higher than those in outdoor pools. The longer opening time and weaker light intensity for indoor pools might cause the difference. The redundancy analysis showed significantly negative correlations between the concentrations of parabens and the contents of residual chlorine in the pool waters. A higher chlorine residue may promote the decomposition of parabens. Health risk assessment showed that skin penetration would be the main approach for the intake of PCPs by swimmers while swimming. Compared with the non-athletic swimmers, the athletic swimmers might be more sensitive, but the health risks for both groups of swimmers could be negligible.


Assuntos
Cosméticos/análise , Monitoramento Ambiental , Poluentes Químicos da Água/análise , Carbanilidas , Cloro/análise , Cromatografia Líquida , Humanos , Parabenos , Medição de Risco , Extração em Fase Sólida , Natação , Piscinas , Triazóis
8.
Chemosphere ; 254: 126891, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32957291

RESUMO

Gut microbiota executes many beneficial functions. In this study, the relationship between gut microbiota and ovarian development in the swimming crab P. trituberculatus was explored for the first time. A total of 28 phyla and 422 genera were identified across all samples. However, 105 differential operational taxonomic units, and four differential phyla (Gemmatimonadetes, Actinobacteria, Firmicutes, Marinimicrobia_(SAR406_clade)) were identified. At the genus level, 42 differential genera were identified and 144 bacterial indicators were identified. A key finding was that the relative abundance of 139 indicator bacteria detected in the anisomycin-2 mg/kg group (AK group) was higher than that of blank group (BK group), control group (CK group), SP600125-15 mg/kg group (SK group). In addition, the relative abundance of three indicator bacteria (OTU_236, OTU_1395, OTU_552) detected in the SK group was higher than that of the BK, CK and AK groups. It was also found that the relative abundance of 20 differential genera (Methyloversatilis, Coprococcus_1, Erysipelotrichaceae_UCG_003, Rikenella, Corynebacterium, Ruminiclostridium, Fusicatenibacter, [Eubacterium]_ruminantium_group, Rikenellaceae_RC9_gut_group, Bifidobacterium, Lachnospiraceae_NK4A136_group, Ruminococcaceae_UCG_014, Christensenellaceae_R_7_group, uncultured_Bacteroidales_bacterium, Coprococcus_2, Desulfovibrio, Aggregatibacter, Ambiguous_taxa, Alloprevotella and Ruminococcaceae_NK4A214_group) in the SK, BK, CK, and AK group samples were increasing. These differential genera may reveal the relationship between gut microbial communities and ovarian development in P. trituberculatus after injection with the JNK pathway inhibitor SP600125 or the activator anisomycin. In summary, this study provides a new understanding into the relationship between gut microbiota and ovarian development in response to stimulation with inhibitor or activator.


Assuntos
Braquiúros/fisiologia , Microbioma Gastrointestinal/fisiologia , Animais , Bactérias/genética , Feminino , Microbioma Gastrointestinal/genética , Microbiota , RNA Ribossômico 16S/genética , Natação
9.
PLoS One ; 15(9): e0237716, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32886676

RESUMO

Bull trout (Salvelinus confluentus) are challenging to detect as a result of the species cryptic behavior and coloration, relatively low densities in complex habitats, and affinity for cold, high clarity, low conductivity waters. Bull trout are also closely associated with the stream bed, frequently conceal in substrate, and this concealment behavior is poorly understood. Consequently, population assessments are problematic and biologists and managers often lack quantitative information to accurately describe bull trout distributions, estimate abundance, and assess status and trends; particularly for stream-dwelling populations. During controlled laboratory trials, we recorded concealment, resting, and swimming behavior of juvenile wild bull trout in response to: (1) constant and fluctuating water temperature, (2) presence or absence of light, and (3) substrate size. Light level had the strongest influence on wild fish concealment and more fish concealed as light levels increased from darkness to daylight. Wild fish were 14.5 times less likely to conceal in constant darkness and 4.1 times more likely to conceal in 12 h light x 12 h darkness compared to constant light. Wild fish were 6.2 times less likely to conceal in small (26-51 mm) substrate compared to larger (52-102 mm) substrate. As water temperature increased, fewer wild fish concealed. Knowledge of wild bull trout concealment will improve field sampling protocols and increase detection efficiencies. These data also enhance knowledge of bull trout niche requirements which illuminates ecological differences among species and informs conservation and restoration efforts.


Assuntos
Truta/fisiologia , Distribuição Animal , Animais , Comportamento Animal , Fotoperíodo , Rios/química , Natação , Temperatura
10.
PLoS One ; 15(9): e0239158, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32966338

RESUMO

Prolonged exercise is known to cause changes in common biomarkers. Occasionally, competition athletes need medical assistance and hospitalisation during prolonged exercise events. To aid clinicians treating patients and medical teams in such events we have studied common biomarkers after at The Norseman Xtreme Triathlon (Norseman), an Ironman distance triathlon with an accumulated climb of 5200 m, and an Olympic triathlon for comparison. Blood samples were collected before, immediately after, and the day following the Norseman Xtreme Triatlon (n = 98) and Oslo Olympic Triathlon (n = 15). Increased levels of clinical significance were seen at the finish line of the Norseman in white blood cells count (WBC) (14.2 [13.5-14.9] 109/L, p < 0.001), creatinine kinase (CK) (2450 [1620-3950] U/L, p < 0.001) and NT-proBNP (576 [331-856] ng/L, p < 0.001). The following day there were clinically significant changes in CRP (39 [27-56] mg/L, p < 0.001) and Aspartate Aminotransferase (AST) (142 [99-191] U/L, p < 0.001). In comparison, after the Olympic triathlon distance, there were statistically significant, but less clinically important, changes in WBC (7.8 [6.7-9.6] 109/L, p < 0.001), CK (303 [182-393] U/L, p < 0.001) and NT-proBNP (77 [49-88] ng/L, p < 0.01) immediately after the race, and in CRP (2 [1-3] mg/L, p < 0.001) and AST (31 [26-41] U/L, p < 0.01) the following day. Subclinical changes were also observed in Hemoglobin, Thrombocytes, K+, Ca2+, Mg2+, Creatinine, Alanine Aminotransferase and Thyroxine after the Norseman. In conclusion, there were significant changes in biomarkers used in a clinical setting after the Norseman. Of largest clinical importance were clinically significant increased WBC, CRP, AST, CK and NT-proBNP after the Norseman. This is important to be aware of when athletes engaging in prolonged exercise events receive medical assistance or are hospitalised.


Assuntos
Atletas , Desempenho Atlético/fisiologia , Ciclismo/fisiologia , Corrida/fisiologia , Natação/fisiologia , Adulto , Biomarcadores/sangue , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade
11.
PLoS One ; 15(8): e0227394, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32866148

RESUMO

The aim of this study was to assess the impact of a 6-week specialized training program aimed at strengthening core muscles to improve the effectiveness of selected elements of a swimming race on a group of Polish swimmers. Sixteen male national level swimmers (21.6 ± 2.2 years) participated in the research. The competitors were randomly assigned to 1 of 2 groups before the data collection process: an experimental (EG, n = 8) and a control (CG, n = 8) group. Both groups of swimmers underwent the same training program in the water environment (volume and intensity), while swimmers from the EG additionally performed specific core muscle training. The task of the swimmers was an individual front crawl swim of 50 m, during which the kinematic parameters of the start jump, turn and swimming techniques were recorded using a video camera system. In both groups, a minor increase in the flight phase was observed at the start (EG = 0.06 m, 1.8%; p = 0.088; CG = 0.08 m, 2.7%; p = 0.013). The time to cover a distance of 5 m after the turn and the recorded average speed in swimming this distance for the EG statistically significantly improved by 0.1 s (-28.6%; p < 0.001) and 3.56 m∙s-1 (23.2%; p = 0.001), respectively. In the EG, a statistically significant improvement in 50 m front crawl swimming performance of 0.3 s (-1.2%, p = 0.001) was observed. The results of the research show that the implementation of isolated strengthening of the stabilizing muscles seems to be a valuable addition to the standard training of swimmers.


Assuntos
Exercício Físico/fisiologia , Condicionamento Físico Humano/métodos , Natação/fisiologia , Desempenho Atlético/fisiologia , Fenômenos Biomecânicos , Terapia por Exercício , Humanos , Masculino , Força Muscular/fisiologia , Músculos , Polônia , Treinamento de Resistência/métodos , Adulto Jovem
12.
Mar Environ Res ; 161: 105054, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32823176

RESUMO

Rising water temperature and increased uptake of CO2 by the ocean are predicted to have widespread impacts on marine species. However, the effects are likely to vary, depending on a species' sensitivity and the geographical location of the population. Here, we investigated the potential effects of elevated temperature and pCO2 on larval growth and survival in a New Zealand population of the Australasian snapper, Chrysophyrs auratus. Eggs and larvae were reared in a fully cross-factored experiment (18 °C and 22 °C/pCO2 440 and 1040 µatm) to 16 days post hatch (dph). Morphologies at 1 dph and 16 dph were significantly affected by temperature, but not CO2. At 1dph, larvae at 22 °C were longer (7%) and had larger muscle depth at vent (14%), but had reduced yolk (65%) and oil globule size (16%). Reduced yolk reserves in recently hatched larvae suggests higher metabolic demands in warmer water. At 16 dph, larvae at elevated temperature were longer (12%) and muscle depth at vent was larger (64%). Conversely, survival was primarily affected by CO2 rather than temperature. Survivorship at 1 dph and 16 dph was 24% and 54% higher, respectively, under elevated CO2 compared with ambient conditions. Elevated temperature increased survival (24%) at 1 dph, but not at 16 dph. These results suggest that projected climate change scenarios may have an overall positive effect on early life history growth and survival in this population of C. auratus. This could benefit recruitment success, but needs to be weighed against negative effects of elevated CO2 on metabolic rates and swimming performance observed in other studies on the same population.


Assuntos
Dióxido de Carbono , Mudança Climática , Animais , Larva , Água do Mar , Natação , Temperatura
13.
Artigo em Inglês | MEDLINE | ID: mdl-32858995

RESUMO

(1) Background: The aim of this study was to design and analyze the validity of the SMACC (Scale to Measure Aquatic Competence in Children) to evaluate aquatic competence in three- to six-year-old children. In addition, the relation between real competence obtained with the SMACC and perceived aquatic competence was verified as well as its differences according to sex and age. (2) Methods: Content validation was performed through the consensus of nine experts using the Delphi technique, and comprehension validity was determined through a pilot study on a sample of 122 children. An exploratory and confirmatory factor analysis was performed with two independent samples of 384 and 444 school children between three and six years old, respectively. (3) Results: After the pertinent adjustments, the final questionnaire comprised 17 items, which showed a good fit for both comprehension and content validity. The results of the exploratory and confirmatory analyses support the use of three dimensions in aquatic competence: motor, socio-affective, and cognitive. The correlations support construct validity showing a positive relation with perceived aquatic competence. (4) Conclusions: These promising validity data are discussed from a global and integrative perspective in relation to the improvement of children's development in the aquatic environment during the early stages of their lives.


Assuntos
Desenvolvimento Infantil , Destreza Motora , Inquéritos e Questionários/normas , Natação , Criança , Pré-Escolar , Análise Fatorial , Humanos , Projetos Piloto , Psicometria/instrumentação , Psicometria/estatística & dados numéricos , Reprodutibilidade dos Testes , Água
14.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 36(2): 161-164, 2020 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-32744012

RESUMO

Objective: To observe the effects of 10-week swimming training on blood pressure and prethrombotic state in spontaneously hypertensive rats (SHR). Methods: Eighteen 10-week-old male SHR were randomly divided into control group (8 rats) and training group (10 rats). The SHR training group underwent weightless swimming training for 10 weeks, five times a week, 60 minutes a time, and blood pressure was measured every two weeks. The platelet aggregation rate, von willebrand factor(vWF), tissue plasminogen activator(t-PA), plasminogen activator inhibitor -1(PAI-1) in plasma were measured after 10 weeks of training. Results: Compared with the control group, blood pressure in SHR training group was decreased significantly(P<0. 05) after 4-week of swimming training, and blood pressure, platelet aggregation rate, plasma vWF level, PAI-1 activity were decreased significantly(P<0. 01), while plasma t-PA activity was increased significantly (P<0. 01) after 10-week of swimming training. Conclusion: Suitable swimming training will effectively reduce the blood pressure of SHR and has a significant effect if persisting in training for 4 weeks, and it also can improve pre-thrombotic state, prevent hypertensive thrombotic complications significantly in SHR.


Assuntos
Pressão Sanguínea , Hipertensão , Condicionamento Físico Animal , Animais , Hipertensão/terapia , Masculino , Distribuição Aleatória , Ratos , Ratos Endogâmicos SHR , Natação
15.
Artigo em Inglês | MEDLINE | ID: mdl-32784446

RESUMO

The avoidance of respiratory muscle fatigue and its repercussions may play an important role in swimmers' health and physical performance. Thus, the aim of this study was to investigate whether a six-week moderate-intensity swimming intervention with added respiratory dead space (ARDS) resulted in any differences in respiratory muscle variables and pulmonary function in recreational swimmers. A sample of 22 individuals (recreational swimmers) were divided into an experimental (E) and a control (C) group, observed for maximal oxygen uptake (VO2max). The intervention involved 50 min of front crawl swimming performed at 60% VO2max twice weekly for six weeks. Added respiratory dead space was induced via tube breathing (1000 mL) in group E during each intervention session. Respiratory muscle strength variables and pulmonary and respiratory variables were measured before and after the intervention. The training did not increase the inspiratory or expiratory muscle strength or improve spirometric parameters in any group. Only in group E, maximal tidal volume increased by 6.3% (p = 0.01). The ARDS volume of 1000 mL with the diameter of 2.5 cm applied in moderate-intensity swimming training constituted too weak a stimulus to develop respiratory muscles and lung function measured in the spirometry test.


Assuntos
Força Muscular , Espaço Morto Respiratório , Natação , Adulto , Humanos , Pulmão , Músculos Respiratórios , Adulto Jovem
16.
Ecotoxicol Environ Saf ; 202: 110963, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32800234

RESUMO

Harmful Phaeocystis blooms disrupt seawater recreation and pose serious challenges to aquatic animals. The growth performance, phenotypic traits, and antioxidant responses of Brachionus plicatilis Müller to different proportions of Phaeocystis globosa were evaluated. B. plicatilis rotifers were exposed to cultures with Chlorella sp. and P. globosa alone and in mixtures of these two algae with proportions of 25%, 50%, and 75%. The total proportions of the two algae were maintained at 100%. Results showed that P. globosa inhibited the rotifer net reproduction rate, intrinsic growth rate, and finite rate of increase (P < 0.01). It induced the formation of defense phenotypic traits in terms of the increased posterolateral spine length and the reduced body length, swimming speed, and grazing rate of B. plicatilis (P < 0.001). Superoxide dismutase and catalase activities decreased, but the reactive oxygen species levels increased as the proportions of P. globosa increased (P < 0.01). The mixture of 50% Chlorella and 50% Phaeocystis positively affected the glutathione content, glutathione peroxidase activity, and generation time of rotifers (P < 0.01). Although P. globosa released toxicants with harmful effects on the growth performance of B. plicatilis, rotifers changed their antioxidant defense system and formed defense phenotypic traits in response to eutrophic conditions.


Assuntos
Antioxidantes/metabolismo , Haptófitas/crescimento & desenvolvimento , Proliferação Nociva de Algas , Rotíferos/crescimento & desenvolvimento , Animais , Chlorella/crescimento & desenvolvimento , Glutationa/metabolismo , Fenótipo , Espécies Reativas de Oxigênio/metabolismo , Rotíferos/metabolismo , Rotíferos/fisiologia , Água do Mar/química , Natação
17.
PLoS One ; 15(8): e0238197, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32841286

RESUMO

The aim of this study was to compare artistic swimmers (ASs) and water polo players (WPs) in their polyrhythmic production ability and entrainment between arm and leg motion frequency. Nine ASs and nine WPs participated in the study. First, we assessed the natural eggbeater kick frequency of each participant without any additional motion for 20 s. We then required the participants to perform a circular arm movement in synchronization with two sequences of metronome rhythms (either 100%, 80% and 120% or100%, 120% and 80% of their natural eggbeater kick frequency) while maintaining their natural eggbeater kick frequency. All tasks were repeated three times. The participants' performances were recorded by a motion capture system synchronized with the metronome. A two-way mixed-design ANOVA was performed on the coefficient of variation of natural eggbeater kick frequency obtained from the first task to confirm the consistency of participants' kicking motion. In the second task, a three-way mixed-design ANOVA was performed on the average frequency of the arm and leg motions to assess the entrainment between the two. In the first task, there were no significant main effects and interaction between group and trial in the coefficient of variation of eggbeater kick frequency, suggesting that both WPs and ASs maintained their natural eggbeater kick frequency equally consistently. In the second task, however, WPs were not able to maintain their natural eggbeater kick frequency when they were required to do circular arm movements at 120% tempo (p < .01). On the other hand, ASs successfully maintained their natural eggbeater kick frequency with all metronome rhythms, suggesting that they have a better polyrhythmic production ability than WPs.


Assuntos
Música , Natação/fisiologia , Esportes Aquáticos/fisiologia , Adolescente , Adulto , Braço/fisiologia , Desempenho Atlético/fisiologia , Fenômenos Biomecânicos , Feminino , Humanos , Perna (Membro)/fisiologia , Masculino , Destreza Motora/fisiologia , Movimento/fisiologia , Amplitude de Movimento Articular/fisiologia , Adulto Jovem
18.
Chemosphere ; 261: 127753, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32745739

RESUMO

Selective serotonin reuptake inhibitors (SSRIs) have been shown to interfere with various physiological functions of aquatic organisms, yet the neuroactive potential of low concentrations of SSRIs in the aquatic environment is unclear. The current study investigated the effects of fluoxetine and citalopram on the visual motor response (VMR) of 107 h old zebrafish (Danio rerio) embryos. Results document a reduction in stress-related swimming activity of zebrafish embryos at environmentally relevant concentration levels, with fluoxetine being more effective than citalopram. Further experiments were designed to elucidate (1) if the lower neuroactive potential of citalopram is due to differences in uptake kinetics, (2) if the metabolite of fluoxetine, norfluoxetine, contributes to the neuroactive potential of fluoxetine, (3) and how SSRIs and their metabolites interact in equimolar mixtures. At the stage of 120 h, zebrafish embryos accumulate citalopram at significantly lower rates (up to 127 times) than fluoxetine. Moreover, it was demonstrated that norfluoxetine reduces the embryonic VMR similarly to fluoxetine resulting in additive effects of these substances on stress-related behavior in zebrafish embryos. In contrast, the interaction of fluoxetine, norfluoxetine and citalopram varied with test concentrations of the equimolar mixtures. Findings provide evidence that environmentally relevant concentrations of fluoxetine reduce stress-related behavior of zebrafish embryos, while these effects may be enhanced by the interaction of multiple SSRIs and their metabolites in environmental exposure scenarios.


Assuntos
Comportamento Animal/efeitos dos fármacos , Embrião não Mamífero/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Inibidores de Captação de Serotonina/toxicidade , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/fisiologia , Animais , Bioacumulação/efeitos dos fármacos , Citalopram/metabolismo , Citalopram/toxicidade , Embrião não Mamífero/metabolismo , Embrião não Mamífero/fisiologia , Exposição Ambiental , Fluoxetina/metabolismo , Fluoxetina/toxicidade , Inibidores de Captação de Serotonina/metabolismo , Natação , Poluentes Químicos da Água/metabolismo
19.
Bull Environ Contam Toxicol ; 105(3): 387-392, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32757041

RESUMO

Systematic studies on the impact of environmental pollution on the survival adaptability of amphibians are relatively few. In this study, Bufo raddei tadpoles from two places with totally different backgrounds of heavy metal pollution were chosen to explore the effects of heavy metal pollution on fitness and swimming performance of tadpoles, the physiological effects were investigated as well. The tadpoles at GS 25, GS 30 and GS 35 were collected randomly from the two study sites and were exposed to different environmental temperatures. The results showed that heavy metal enrichment and antioxidant levels were significantly higher in the tadpoles under long-term heavy metal stress. Meanwhile, heavy metal pollution affected the adaptability of tadpoles to environmental change and decreased the swimming performance of the tadpoles. Unexpected, the tadpoles from heavy metal-polluted area also showed some adaptive changes, mainly reflected in the increase in swimming endurance.


Assuntos
Larva/fisiologia , Metais Pesados/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Bufonidae , Poluentes Ambientais , Poluição Ambiental , Larva/efeitos dos fármacos , Metais Pesados/análise , Natação
20.
PLoS One ; 15(8): e0236504, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32745109

RESUMO

The aim of this study was to compare underwater fin swimming performance using dolphin, flutter and breaststroke kicks with and without diving gear. Performance was evaluated in terms of average swimming velocity. The parameters of spatiotemporal structure of the stroke reflecting to the swimming economy were employed. Conscious modifications in propulsion technique were considered here with the aim of controlling swimming performance. A total of ten professional scuba divers swam at maximal speed underwater for 50m using each of three techniques: dolphin, flutter, or breaststroke kicks. Swimmers' performance was compared between holding their breath and using breathing apparatus. Two cameras recorded their movements in sagittal and transverse planes. The average swimming velocity (vav), stroke length (SL), stroke rate (SR), index of variation of intracycle velocity (VIVIndex) and stroke index (SI) were estimated. Relative to the other techniques, the dolphin kick without a diving gear demonstrated the highest vav and low SI and VIVIndex values, which reflects the most advantageous economy of propulsion at given velocity. Given the lack of statistical differences, using the breaststroke kick and flutter kick when swimming with a diving gear seems to be comparable to dolphin-kick in terms of average velocity and parameters reflecting the economy of propulsion. Thus, a search for fin swimming techniques with the aim of achieving specific goals seemed reasonable. The results suggest, that performance achieved while using various fin swimming techniques was probably controlled by different strategies of leg movements. These strategies revealed differences in a spatiotemporal (SR-SL) structure of the stroke and they were closely associated in terms of the velocity variation decrease.


Assuntos
Fenômenos Biomecânicos/fisiologia , Mergulho/fisiologia , Golfinhos/fisiologia , Natação/fisiologia , Animais , Braço/fisiologia , Humanos , Masculino , Movimento/fisiologia
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