Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “SWIMMING”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 865 records · Page 48Linked to original sources
PubMed1995

[In vivo neurochemical effects of electroconvulsive shock on the forced swimming rat].

The effects of electroconvulsive shock (ECS) on monoamine metabolism in the forced swimming rat were studied using on-line microdialysis. In the present experiment, we measured forced swimming-induced immobility time and interstitial concentrations of dopamine (DA), its metabolites 3,4-dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA) and serotonin (5-HT), its metabolite 5-hydroxyindoleacetic acid (5-HIAA) in the anterior hypothalamus. Mean immobility time was short in the ECS-treated group compared with shamECS group but the difference was not statistically significant. DA and 5-HT tended to increase following a single ECS. Interstitial concentration of 5-HIAA increased significantly. Forced swimming test caused an increase in both DA and 5-HT turnover in the hypothalamus. In contrast, pretreatment with ECS tends to suppress these forced swimming-induced increases in DA and 5-HT turnover. These data suggest that ECS may regulate excess activation in central dopaminergic and serotonergic system following forced swimming stress.

Animals↗
PubMed1993

Swimming performance of rainbow trout following exposure and recovery from the pyrethroid S-deltamethrin.

Oxygen consumption and swimming performance of rainbow trout exposed to sublethal concentrations (10-50 microliters/20 L) of pyrethroid (S-deltamethrin) pesticide was studied in a Brett-type respirometer during recovery. Results showed wide variations reflecting the varied responses of different individual fish to the test regime. In most cases values of oxygen consumption for the controls were higher at each swimming speed and this became significantly reduced following treatment with pesticide. Oxygen consumption soon after the treatment gave the highest values but these fish were unable to sustain swimming speeds as high as the controls or following recovery. The comparisons of swimming performance before and after treatments with deltamethrin have shown a significant effect on locomotory ability of rainbow trout which at the end of strong exposure (e.g. 50 min of 40 microliters/20 L) are almost incapable of swimming.

Animals↗
PubMed1993

Effect of water temperature on performance, lactate production and heart rate at swimming of maximal and submaximal intensity.

The effect of water temperature on performance effort, monitored heart rate and lactate production during freestyle swimming at maximal and submaximal speed has been studied. Fifteen male sprint swimmers performing 100 m swimming and fifteen comparable endurance competitors performing 30 min swimming at submaximal speed served as subjects. Water temperature in separate events was 20, 26 and 32 degrees C. At maximal performance there was a direct relationship between any two of the following parameters: water temperature, average swimming speed, heart rate during the competition and plasma lactate concentration after the event. Thus, the best effort (speed 1.704 m/s), the highest peak heart rate (185 beats/min) and the highest lactate level (19.8 mmol/l) were observed at 32 degrees C (all mean values). In contrast, these values were markedly lower at 20 degrees C. At the submaximal effort, water temperature was related to peak heart rate only. The highest peak heart rate (144 beats/min) was again obtained at 32 degrees C, while the lactate concentration (4.2-5.2 mmol/l) was independent of temperature. Water temperature appears to have a direct effect on performance effort, heart rate and lactate production during swimming at maximal intensity, whereas this effect seems to fade at submaximal efforts.

Adolescent↗
PubMed1995

Invertebrate swimming: integrating internal and external mechanics.

Challenges in understanding design for locomotion in any swimming animal revolve around the complex interactions between the mechanics of fluid motions around an animal and the mechanics of internal force production. The former is governed by force-velocity relationships that arise from fluid motion, whereas the latter is governed by force-velocity relationships of both active (e.g. muscle) and passive tissues. In reality, all such relationships must be satisfied simultaneously in any swimming creature. Towards this end, I combine traditional analyses of muscle contractility, soft tissue mechanics and hydrodynamic models to examine how organism morphology, muscle physiology and mode of propulsion interact to affect swimming performance. This combination involves a solution to a set of equations that describe the relevant internal and external mechanics. The solution has the unique benefit of providing predictions for both body and propulsor kinematics. Such predictions are examined for a variety swimming animals and are compared with existing kinematic data. Armed with such an approach, I re-examine traditional scaling arguments to show that classical approaches that neglect internal mechanics predict swimming performance relationships that may not be physiologically feasible.

Animals↗
PubMed1997

Neonatal administration of the selective serotonin reuptake inhibitor Lu 10-134-C increases forced swimming-induced immobility in adult rats: a putative animal model of depression?

Chronic administration of the tricyclic antidepressant clomipramine to neonatal rats from postnatal days 8 to 21 is reported to induce several behavioral changes in adult life, and it may serve as an animal model of human depressive disorder. Findings include increased immobility time in the forced swim test and locomotor hyperactivity in the open field test. Clomipramine is a serotonergic reuptake inhibitor, which suggests that altered development of the serotonergic system could account for the observed behavioral changes in the adult rat. The present study was carried out with a selective serotonin reuptake inhibitor (SSRI) to investigate whether the serotonin system, in particular, is involved in the neonatal animal model. The substance, Lu 10-134-C (LU), was characterized in monoamine reuptake and receptor binding assays and found to be an SSRI. Rats received LU during postnatal days 8 to 21 (2.5-15 mg/kg b. i.d.), and they were assessed in open field, forced swim and social interaction tests at the age of 4 months. Behavior of LU-treated rats and saline controls did not differ in the open field and social interaction tests. However, in the forced swim tests LU-treated neonates showed prolonged immobility time compared with saline controls. In conclusion, chronic LU treatment during neonatal life produces long-term changes in the forced swim test, but not in the open field and social interaction tests. The behavioral changes in the forced swim test suggest that the central serotonergic system may be involved in the putative neonatal animal model of depression.

Animals↗
PubMed1997

Swimming performances and stroking parameters in non skilled grammar school pupils: relation with age, gender and some anthropometric characteristics.

OBJECTIVE: It was hypothesized that swimming velocity (V) and stroking parameters such as stroke length (SL), stroke rate (SR) and stroke index (SI) are influenced by age, gender, and some anthropometric characteristics. EXPERIMENTAL DESIGN: Cross-sectional study. SETTING: Grammar school pupils from French schools. PARTICIPANTS: One thousand and ninety-seven males and 961 females non skilled swimmers aged from 11 to 17. INTERVENTIONS: Usual swimming sessions (6 +/- 2 h.year-1) during a physical education program at school. MEASURES: V, SL, SF and SI (SI = V.SL) were measured or calculated from a 50-m crawl sprint and height, arm span and body mass were measured for all subjects. RESULTS: The results showed that V, SL and SI increased regularly (p < 0.01) in relation to age in both genders. SL was never significantly different between males and females. SF remained unchanged according to age and was significantly higher in males than in females. V, SL and SI were influenced by age and arm span but not SF. CONCLUSIONS: As males and females were submitted to the same swimming teaching program at school, a higher increase in muscle power and anaerobic capacity in males could explain the gender differences. These results observed in non skilled swimmers showed that the differences in stroking parameters between genders were the reverse of those of top level swimmers and that they can be used by swimming teachers in order to build some assessment tools and to better understand the improvements in swimming in relation to growth and gender.

Adolescent↗
PubMed2006

Structure and autonomic innervation of the swim bladder in the zebrafish (Danio rerio).

Many teleosts actively regulate buoyancy by using a gas-filled swim bladder, which is thought to be under autonomic control. Here we investigated the swim bladder in the zebrafish to determine possible mechanisms of gas-content regulation. Fluorescently labelled phalloidin revealed myocytes that appeared to form a possible sphincter at the junction of the pneumatic duct and esophagus. Myocytes also formed thick bands along the ventral surface of the anterior chamber and bilaterally along the posterior chamber. Thinner layers of myocytes were located elsewhere. Staining of peroxidase within erythrocytes revealed a putative rete and smaller blood vessels in muscle bands and elsewhere. The antibodies zn-12, a general neuronal marker, and SV2, a synaptic vesicle marker labelling presynaptic terminals, revealed widespread innervation of the swim bladder system. Widespread innervation of the swim bladder was also indicated by acetylcholinesterase histochemistry, but choline acetyltransferase-immunoreactive (-IR) somata and fibers were limited to the junction of the pneumatic duct and esophagus. In contrast, varicose tyrosine hydroxylase-IR fibers innervated muscles and blood vessels throughout the system. Neuropeptide Y-IR somata were located near the junction of the duct and esophagus and varicose fibers innervated muscles and vasculature of the posterior chamber and duct. Vasoactive intestinal polypeptide immunoreactivity was abundant throughout the anterior chamber but sparsely distributed elsewhere. Serotonin-IR fibers and varicosities were located only along blood vessels near the junction of the pneumatic duct and posterior chamber. Our results suggest that the zebrafish swim bladder is a complex and richly innervated organ and that buoyancy-regulating effectors may be controlled by multiple populations of autonomic neurons.

Acetylcholinesterase↗
PubMed1990

Okadaic acid, an inhibitor of protein phosphatase 1 in Paramecium, causes sustained Ca2(+)-dependent backward swimming in response to depolarizing stimuli.

Backward swimming is a stereotypic behavioural response of Paramecium. It is triggered by depolarizing stimuli, which open calcium channels in the excitable ciliary membrane. The influx of Ca2+ causes the reversal of ciliary beat and initiates backward swimming. Here, we demonstrate that the protein phosphatase inhibitor okadaic acid does not affect the normal forward swimming pattern of Paramecium, but greatly extends the duration of backward swimming as initiated by depolarization caused by a rise in extracellular K+. Chelation of external Ca2+ results in an immediate resumption of forward swimming. The results suggest that the voltage-operated calcium channel is inactivated by a dephosphorylation event, and that okadaic acid blocks this dephosphorylation without any effect on the motile apparatus of the cilia. In addition, Paramecium is unique among eukaryotic cells, in that okadaic acid inhibits just one protein phosphatase, namely a type 1 enzyme, 75% of which is tightly associated with the excitable ciliary membrane. The type 2A protein phosphatases in Paramecium are unaffected by okadaic acid. The results indicate that protein phosphatase 1 is the enzyme responsible for the dephosphorylation and closure of the calcium channel in Paramecium.

Animals↗
PubMed2002

Membrane sorting during swimming internalization of Brucella is required for phagosome trafficking decisions.

Brucella infects macrophages by swimming internalization, after which it is enclosed in macropinosomes. We investigated the role of the uptake pathway in phagosome trafficking, which remains unclear. This study found membrane sorting during swimming internalization and is essential in intracellular replication of Brucella. The B. abortus virB mutant replicated intracellularly when it was in the macropinosome established by wild-type B. abortus that retained its ability to alter phagosome trafficking. Lipid rafts-associated molecules, such as GM1 ganglioside, were selectively included into macropinosomes, but Rab5 effector early endosome autoantigen (EEA1) and lysosomal glycoprotein LAMP-1 were excluded from macropinosomes containing B. abortus induced by swimming internalization. In contrast, when the swimming internalization was bypassed by phorbol myristate acetate (PMA)-induced macropinocytosis, lipid raft-associated molecules were excluded, and EEA1 and LAMP-1 were included into macropinosomes containing bacteria. The phosphatidylinositol 3-kinase inhibitor wortmannin that inhibits PMA-induced macropinocytosis blocked internalization of virB mutant, but not of wild-type of B. abortus and wortmannin treatment did not affect intracellular replication. Our results suggest that membrane sorting requires swimming internalization of B. abortus and decides the intracellular fate of the bacterium, and that Brucella -induced macropinosome formation is a different mechanism from PMA-induced macropinocytosis.

Animals↗
PubMed1995

Active behaviors in the rat forced swimming test differentially produced by serotonergic and noradrenergic antidepressants.

This study demonstrated that distinct patterns of active behaviors are produced by antidepressants that selectively inhibit norepinephrine (NE) or serotonin (5-HT) uptake in the rat forced swimming test (FST). A behavior sampling technique was developed to score the active behaviors swimming, climbing and diving, as well as immobility. The rat's behavior was recorded at the end of each 5-s period during the test session. The sampling technique was both reliable, as demonstrated by test-retest reliability and inter-rater reliability, and valid, as shown by comparison to the timing of behavior durations. Five different antidepressant drugs which block monoamine uptake and two 5-HT1A receptor agonists were shown to decrease immobility in the FST; however, they produced distinct patterns of active behaviors. The selective NE uptake inhibitors desipramine and maprotiline selectively increased climbing, whereas the selective serotonin reuptake inhibitors (SSRIs) fluoxetine, sertraline and paroxetine selectively increased swimming. The 5-HT1A receptor agonists 8-OH-DPAT and gepirone also selectively increased swimming. These results show that:1) SSRIs are not false negatives in the FST; 2) at least two behaviorally distinct processes occur in the FST; and 3) enhancement of NE neurotransmission may mediate climbing in the FST, whereas enhancement of 5-HT neurotransmission may mediate swimming.

Animals↗
PubMed1993

Impaired acquisition of swimming navigation in adult mice exposed prenatally to oxazepam.

Prenatally administered oxazepam (OX) impairs adult radial maze performance in mice, possibly by permanent hippocampal changes. CDI mice were tested in swimming navigation, a sensitive indicator for hippocampal damage. Ten males and ten females were exposed to OX on fetal days 12-16 by maternal administration PO of 30 mg/kg/day and fostered at birth to untreated dams, while control mice received vehicle solution. All mice were tested at 8-9 weeks for ability to find a submerged platform in a fixed location (acquisition: 18 trials, 6 trials per day) and for capacity to re-orient towards a new platform position (reversal: 12 trials, 6 trials per day). OX mice showed a slight but significant impairment of swimming navigation during the initial part of training, as indicated by longer swimming paths during the fourth and fifth trial (day 1), an impairment due both to delayed habituation to the novel stressfull condition and acquisition of platform climbing but unrelated to navigational abilities. No treatment-dependent differences were observed in the reversal phase. During reversal, both OX and control females spent significantly more time in swimming across the location of the old platform. Unrelated to navigational performance, females showed a slightly but significantly higher swimming speed than males. Due to the absence of any navigational impairment, data suggest that prenatal exposure to oxazepam exerts long-term influence on adult learning capacities primarily through interaction with brain systems located outside the hippocampus.

Animals↗
PubMed1985

Glucocorticoids facilitate the retention of acquired immobility during forced swimming.

The adrenalectomy-induced decrease in the level of immobility during a 5 min retest period in the Porsolt swimming test could be reversed by glucocorticoids administered s.c. 15 min after the initial forced swimming exposure. The synthetic glucocorticoids dexamethasone and RU 28362 were active in the microgram dose range while corticosterone was only active at a 500 times higher dose. Aldosterone and progesterone were both ineffective. Treatment of adrenalectomized rats with the synthetic antiglucocorticoid RU 38486 prior to dexamethasone administration dose dependently blocked the effect of the glucocorticoid. Intact rats treated with the antiglucocorticoid RU 38486 prior to the initial forced swimming exposure behaved like adrenalectomized animals during the 5 min retest period. Removal of the adrenal medulla only temporarily impaired swimming behavior. It is concluded that intact adrenocortical secretion of glucocorticoids is sufficient for retention of acquired immobility during forced swimming.

Abortifacient Agents, Steroidal↗
PubMed1995

Sex differences in the expression and antagonism of swim stress-induced analgesia in deer mice vary with the breeding season.

Swim stress-induced analgesia (SSIA) was examined in photoperiodically induced 'breeding' (reproductive) and 'non-breeding' (non-reproductive) adult male and female deer mice, Peromyscus maniculatus. Nociceptive responses (50 degrees C, hot-plate) of breeding and non-breeding deer mice were determined after either a 1- or 3-min swim in 20 degrees C water. The 1-min swim induced an immediate and relatively short-lasting naloxone (1.0 mg/kg) insensitive 'non-opioid' -mediated SSIA that was antagonized by the N-methyl-D-aspartate (NMDA) antagonist, MK-801 (0.10 mg/kg) in all of the groups of mice except the breeding (reproductive) females. Breeding females displayed a non-opioid analgesia that was insensitive to MK-801. The 3-min swim induced a relatively more prolonged mixed opioid and 'non-opioid' SSIA of which the initial portion was sensitive to antagonism by MK-801 in all groups of the mice except the breeding females, while the latter portion (15 min after swim) was induced by naloxone in all of the groups of mice. Overall, the breeding males displayed greater levels of SSIA than the breeding females, with no consistent sex differences in the non-breeding mice. Within sexes, the breeding males displayed greater levels of opioid and non-opioid SSIA than the non-breeding males, while the non-breeding females displayed greater levels of SSIA than the breeding females. These results show that both sex and reproductive status affect the expression and neurochemical mediation of non-opioid SSIA. These findings also suggest that reproductive females may have an unique or novel hormonally (estrogen) dependent mechanism associated with the expression of SSIA.

Analgesia↗
PubMed2004

Dietary fatty acid composition affects the repeat swimming performance of Atlantic salmon in seawater.

Repeated critical swimming performance trials (Ucrit) were performed on Atlantic salmon (Salmo salar) to test the null hypothesis that the source of dietary lipids (fish-based, poultry-based, and plant-based) does not influence exercise and recovery performance. Four diets were prepared by extensively replacing supplemental lipid from anchovy oil (AO; 100% AO at 150 g/kg) with cold pressed flaxseed oil (FO; 25% AO, 75% FO), sunflower oil (SO; 25% AO, 75% SO), or poultry fat (PF; 25% AO, 75% PF). These diets had equivalent protein and energy concentrations, but due to the different supplemental lipid sources, varied widely in their fatty acid composition. Fish fed AO had a significantly higher (P<0.05) first Ucrit (2.62+/-0.07 body lenght s(-1)) than those fed PF (2.22+/-0.12 body lenght s(-1)) that had low muscle ratios of n-3 highly unsaturated fatty acids (n-3 HUFA) to saturated fatty acids (SFA) and arachidonic acid (AA), and high levels of oleic acid. Fish in the FO and SO diet groups swam as well as AO-fed fish in both swimming trials. The performance of fish fed AO decreased significantly (P<0.05) during the second swimming trial (i.e. Ucrit2/Ucrit1=0.92+/-0.02). No significant differences occurred between diet groups for the second swim trial. There was a positive correlation between both n-3 HUFA/SFA and n-3 HUFA/AA ratios, and Ucrit1. A negative correlation was found between dietary AA and oleic acids, and Ucrit1. The present study suggests that low dietary n-3 HUFA/ SFA and n-3 HUFA/AA ratios may negatively affect swimming performance. The former possibly can be offset by increasing linoleic acid in the presence of nutritionally adequate n-3 HUFA (e.g. SO diet). Lipid supplements consisting largely of vegetable oils did not compromise fish cardiorespiratory physiology under the conditions of this study.

Animals↗
PubMed2004

Synergistic interaction between mazindol, an anorectic drug, and swim-stress on analgesic responses in the formalin test in mice.

The present study examined the interaction between mazindol (MZ), an anorectic drug extensively used in Brazil and opioid/non-opioid endogenous analgesic systems activated by swim-stress. Further, the role of opioid, dopamine and N-methyl-D-aspartate (NMDA) receptors in mediating the analgesic effect was evaluated. The stress-induced analgesia of a 3-min swimming at 32 degrees C (opioid/non-opioid) and 20 degrees C (non-opioid) were assessed using the formalin test. Male Swiss mice were intraperitoneally injected with naloxone (1.0 mg/kg), sulpiride (3.0 mg/kg), MK-801 (0.075 mg/kg) or saline/vehicle 15 min prior, and with MZ (0.5 mg/kg) or saline/vehicle 5 min prior to swimming. The dose of MZ (0.5 mg/kg) did not cause analgesic effect, however, the association of MZ and swim-stress at both temperatures displayed synergistic interaction on analgesia that was blocked by sulpiride and MK-801 but not by naloxone. The present results suggest that MZ and swim-stress acted synergistically on analgesic responses, involving mainly the non-opioid component and possibly mediated by dopamine D2 receptors and NMDA receptors.

Animals↗
PubMed1987

Aerobic and anaerobic swimming speeds of spermatozoa investigated by twin beam laser velocimetry.

The motility of bovine and ovine spermatozoa has been studied under aerobic and anaerobic conditions, using a dual beam laser velocimeter. Cells swimming under aerobic conditions were found to be characterized by a translational swimming speed and a rotation rate that were approximately double those of cells swimming in an anaerobic environment. Both types of spermatozoa have been found to exhibit a sudden coordinated transition between fast and slow swimming states when the available oxygen is exhausted. This transition from aerobic to anaerobic swimming states has also been shown to be reversible. Studies of the duration of aerobic motility using the same apparatus have shown that the cells have a constant motile efficiency over the temperature range 32 degrees-42 degrees C.

Aerobiosis↗
PubMed2001

Group housing of mice increases immobility and antidepressant sensitivity in the forced swim and tail suspension tests.

The forced swim test and tail suspension test are often used in laboratory practice to identify compounds that possess antidepressant-like activity. This experiment was conducted to determine whether housing conditions per se influence the response of mice in these antidepressant screening procedures. Male NIH Swiss mice were housed individually or in groups (five per cage) for 8 weeks prior to testing. After 8 weeks, the animals were exposed to the forced swim and tail-suspension tests. Group housed mice displayed high levels of immobility in the forced swim and tail suspension tests. Desipramine injection 60 min prior testing, in doses 7.5 and 15 mg/kg, produced significant reductions in the immobility time in forced swimming and tail suspension tests. Individually housed mice, when exposed to these tests, displayed lower levels of immobility with a magnitude comparable to the effect of desipramine in group housed mice. Desipramine given to individually housed mice did not reduce the duration of immobility either in the forced swim test or in the tail suspension test. These results indicate that both tests are sensitive to housing conditions. This observation suggests that long lasting group housing may be critical to the behavioral response in these preclinical screening procedures in mice.

Animals↗
PubMed1992

Poor in vitro fertilization outcome with semen yielding low sperm density "swim-ups" is not because of altered sperm motion parameters.

OBJECTIVE: To examine fertilization, cleavage, and pregnancy rates (PRs) with semen samples yielding numbers of total motile sperm per swim-up ranging from < 1 to > 20 x 10(6) and to correlate the findings with changes, if any, in the sperm motion parameters. DESIGN: Fertilization, cleavage, and pregnancy outcomes in 439 in vitro fertilization (IVF) cycles were correlated with the total number of motile sperm per swim-up and the sperm motion parameters as determined with an automated semen analyzer. SETTING: A university-based tertiary referral hospital center. PATIENTS: Patients undergoing IVF or intrauterine insemination treatments for multiple etiologies. RESULTS: Higher numbers of motile sperm per swim-up, most notably above the value of 3 x 10(6) motile sperm, were associated with improved fertilization rates and viable PRs. Sperm velocity, linearity, amplitude of lateral head displacement, and flagellar beat per cross frequency for sperm from swim-ups with poor or good pregnancy outcome, however, showed no significant differences. CONCLUSIONS: As a group, semen samples that yield < or = 3 x 10(6) motile sperm per swim-up are associated with poor fertilization rates, cleavage rates, and PRs. This relationship can not be attributed to differences in sperm motion parameters.

Cell Division↗