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1.
Cell Mol Life Sci ; 81(1): 285, 2024 Jul 06.
Article de Anglais | MEDLINE | ID: mdl-38969941

RÉSUMÉ

Volume regulation is essential for cell homeostasis and physiological function. Amongst the sensory molecules that have been associated with volume regulation is the transient receptor potential vanilloid 4 (TRPV4), which is a non-selective cation channel that in conjunction with aquaporins, typically controls regulatory volume decrease (RVD). Here we show that the interaction between orthologous AQP4 (Aqp4a) and TRPV4 (Trpv4) is important for regulatory volume increase (RVI) in post-activated marine fish spermatozoa under high osmotic stress. Based upon electrophysiological, volumetric, and in vivo and ex vivo functional experiments using the pharmacological and immunological inhibition of Aqp4a and Trpv4 our model suggests that upon ejaculation and exposure to the hypertonic seawater, spermatozoon shrinkage is initially mediated by water efflux through Aqp1aa in the flagellar tail. The shrinkage results in an increase in intracellular Ca2+ concentration, and the activation of sperm motility and a Na+/K+/2Cl- (NKCC1) cotransporter. The activity of NKCC1 is required for the initiation of cell swelling, which secondarily activates the Aqp4a-Trpv4 complex to facilitate the influx of water via Aqp4a-M43 and Ca2+ via Trpv4 and L-type channels for the mediation of RVI. The inhibitory experiments show that blocking of each of these events prevents either shrinkage or RVI. Our data thus reveal that post-activated marine fish spermatozoa are capable of initiating RVI under a high hypertonic stress, which is essential for the maintenance of sperm motility.


Sujet(s)
Taille de la cellule , Pression osmotique , Mobilité des spermatozoïdes , Spermatozoïdes , Canaux cationiques TRPV , Animaux , Mâle , Canaux cationiques TRPV/métabolisme , Canaux cationiques TRPV/génétique , Spermatozoïdes/métabolisme , Mobilité des spermatozoïdes/physiologie , Aquaporine-4/métabolisme , Aquaporine-4/génétique , Calcium/métabolisme , Poissons/métabolisme , Poissons/physiologie , Natation , Membre-2 de la famille-12 des transporteurs de solutés/métabolisme , Membre-2 de la famille-12 des transporteurs de solutés/génétique
2.
Braz J Med Biol Res ; 57: e13452, 2024.
Article de Anglais | MEDLINE | ID: mdl-38958368

RÉSUMÉ

The misuse of anabolic androgenic steroid associated or not with physical workouts disrupts gastrointestinal (GI) function homeostasis. Our goal was to investigate the effects of nandrolone decanoate (ND) and moderate swimming on the GI transit of solid meals, GI motor contractility, and intestinal histology in rats. Male Wistar rats were allocated to four groups that received intramuscular injections of ND (5.0 mg/kg) or vehicle (60.0 µL) and were submitted or not to swimming sessions (60 min, 5% body weight overload) for 4 weeks. Gastric emptying, intestinal transit, in vitro GI contractility, intestinal morphometry, and duodenal mucosal mast cells were evaluated in all experimental groups. ND treatment accelerated gastric emptying, slowed small intestine transit time, enhanced gastric carbachol-mediated reactivity, decreased crypt depth and villus height, reduced mucosal thickness, and increased the circular and longitudinal muscle layer thickness of the duodenum in sedentary rats. Moderate exercise accelerated intestinal transit time and reduced submucosa thickness. In vehicle-treated animals, a strong negative correlation was found between intestinal transit and mucosal mast cells, which was reversed by ND treatment. Combining ND treatment and swimming accelerated gastric emptying, increased duodenal cholinergic reactivity, inhibited the sodium nitroprusside relaxing response, increased the number of duodenal mast cells, decreased villus height, and increased the thickness of all muscle layers. ND changed the morphological and functional properties of the GI tract over time, with intense dysmotility, especially in sedentary animals, but moderate exercise seemed to have played a compensatory role in these harmful effects in the gut.


Sujet(s)
Anabolisants , Duodénum , Motilité gastrointestinale , Décanoate de nandrolone , Nandrolone , Conditionnement physique d'animal , Rat Wistar , Animaux , Mâle , Décanoate de nandrolone/pharmacologie , Duodénum/effets des médicaments et des substances chimiques , Motilité gastrointestinale/effets des médicaments et des substances chimiques , Anabolisants/pharmacologie , Nandrolone/pharmacologie , Nandrolone/analogues et dérivés , Mastocytes/effets des médicaments et des substances chimiques , Rats , Natation , Vidange gastrique/effets des médicaments et des substances chimiques , Muqueuse intestinale/effets des médicaments et des substances chimiques , Transit gastrointestinal/effets des médicaments et des substances chimiques
3.
PLoS One ; 19(7): e0306700, 2024.
Article de Anglais | MEDLINE | ID: mdl-38990841

RÉSUMÉ

Cells and microorganisms are motile, yet the stationary nature of conventional microscopes impedes comprehensive, long-term behavioral and biomechanical analysis. The limitations are twofold: a narrow focus permits high-resolution imaging but sacrifices the broader context of organism behavior, while a wider focus compromises microscopic detail. This trade-off is especially problematic when investigating rapidly motile ciliates, which often have to be confined to small volumes between coverslips affecting their natural behavior. To address this challenge, we introduce Trackoscope, a 2-axis autonomous tracking microscope designed to follow swimming organisms ranging from 10µm to 2mm across a 325cm2 area (equivalent to an A5 sheet) for extended durations-ranging from hours to days-at high resolution. Utilizing Trackoscope, we captured a diverse array of behaviors, from the air-water swimming locomotion of Amoeba to bacterial hunting dynamics in Actinosphaerium, walking gait in Tardigrada, and binary fission in motile Blepharisma. Trackoscope is a cost-effective solution well-suited for diverse settings, from high school labs to resource-constrained research environments. Its capability to capture diverse behaviors in larger, more realistic ecosystems extends our understanding of the physics of living systems. The low-cost, open architecture democratizes scientific discovery, offering a dynamic window into the lives of previously inaccessible small aquatic organisms.


Sujet(s)
Microscopie , Microscopie/méthodes , Microscopie/instrumentation , Microscopie/économie , Animaux , Amoeba/physiologie , Locomotion/physiologie , Natation/physiologie
4.
Clinics (Sao Paulo) ; 79: 100435, 2024.
Article de Anglais | MEDLINE | ID: mdl-38996724

RÉSUMÉ

OBJECTIVE: This study mainly explores (2R,6R; 2S,6S)-HNK and its compounds whether there are antidepressant effects. METHODS: Four HNK compounds were obtained from 2-(Chlorophenyl) Cyclopentylmethanone. Forced swimming test, locomotor sensitization test, and conditioned location preference test were used to screen the antidepressant activity of the synthesized target compounds. RESULTS: In the case of 10 mg HNK treatment, compared with saline, the immobile time of mice in the HNK group, I5 group and I6 group at 1 h and 7 days had statistical significance. In the case of 10 mg HNK treatment, compared with saline, the immobile time of compound C and D groups in the glass cylinder area was significantly different. In the locomotor sensitization test, the movement distance of compound C and D groups on day 15 and day 7 mice increased significantly compared with the first day. In the conditioned place preference experiment, compound C and compound D induced conditioned place preference in mice compared with the Veh group. CONCLUSION: The results of the forced swimming test, locomotor sensitization test, and conditioned location preference test showed that compounds C and D may have certain anti-depressant activity. However, HNK exerts a rapid and significant antidepressant effect within 1 week, but the duration is short.


Sujet(s)
Antidépresseurs , Kétamine , Activité motrice , Natation , Animaux , Antidépresseurs/pharmacologie , Antidépresseurs/usage thérapeutique , Souris , Mâle , Kétamine/pharmacologie , Kétamine/analogues et dérivés , Activité motrice/effets des médicaments et des substances chimiques , Facteurs temps , Comportement animal/effets des médicaments et des substances chimiques , Dépression/traitement médicamenteux , Modèles animaux de maladie humaine , Reproductibilité des résultats
5.
J R Soc Interface ; 21(216): 20240141, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-38955227

RÉSUMÉ

Natural swimmers and flyers can fully recover from catastrophic propulsor damage by altering stroke mechanics: some fish can lose even 76% of their propulsive surface without loss of thrust. We consider applying these principles to enable robotic flapping propulsors to autonomously repair functionality. However, direct transference of these alterations from an organism to a robotic flapping propulsor may be suboptimal owing to irrelevant evolutionary pressures. Instead, we use machine learning techniques to compare these alterations with those optimal for a robotic system. We implement an online artificial evolution with hardware-in-the-loop, performing experimental evaluations with a flexible plate. To recoup thrust, the learned strategy increased amplitude, frequency and angle of attack (AOA) amplitude, and phase-shifted AOA by approximately 110°. Only amplitude increase is reported by most fish literature. When recovering side force, we find that force direction is correlated with AOA. No clear amplitude or frequency trend is found, whereas frequency increases in most insect literature. These results suggest that how mechanical flapping propulsors most efficiently adjust to damage may not align with natural swimmers and flyers.


Sujet(s)
Robotique , Animaux , Poissons/physiologie , Natation , Phénomènes biomécaniques , Modèles biologiques , Insectes/physiologie
6.
Nat Commun ; 15(1): 5936, 2024 Jul 15.
Article de Anglais | MEDLINE | ID: mdl-39009560

RÉSUMÉ

Jellyfish exhibit innovative swimming patterns that contribute to exploring the origins of animal locomotion. However, the genetic and cellular basis of these patterns remains unclear. Herein, we generated chromosome-level genome assemblies of two jellyfish species, Turritopsis rubra and Aurelia coerulea, which exhibit straight and free-swimming patterns, respectively. We observe positive selection of numerous genes involved in statolith formation, hair cell ciliogenesis, ciliary motility, and motor neuron function. The lineage-specific absence of otolith morphogenesis- and ciliary movement-related genes in T. rubra may be associated with homeostatic structural statocyst loss and straight swimming pattern. Notably, single-cell transcriptomic analyses covering key developmental stages reveal the enrichment of diapause-related genes in the cyst during reverse development, suggesting that the sustained diapause state favours the development of new polyps under favourable conditions. This study highlights the complex relationship between genetics, locomotion patterns and survival strategies in jellyfish, thereby providing valuable insights into the evolutionary lineages of movement and adaptation in the animal kingdom.


Sujet(s)
Scyphozoa , Analyse sur cellule unique , Natation , Animaux , Scyphozoa/génétique , Scyphozoa/physiologie , Diapause/génétique , Génomique/méthodes , Génome/génétique , Transcriptome , Analyse de profil d'expression de gènes
7.
J Physiol Sci ; 74(1): 36, 2024 Jul 16.
Article de Anglais | MEDLINE | ID: mdl-39014320

RÉSUMÉ

Exercise increases the pain threshold in healthy people. However, the pain threshold modulation effect of exercise and hawthorn is unclear because of its potential benefits in people with persistent pain, including those with Alzheimer's disease. Accordingly, after the induction of Alzheimer's disease by trimethyl chloride, male rats with Alzheimer's disease were subjected to a 12-week training regimen consisting of resistance training, swimming endurance exercises, and combined exercises. In addition, hawthorn extract was orally administered to the rats. Then, their pain threshold was evaluated using three Tail-flick, Hot-plate, and Formalin tests. Our results showed that Alzheimer's decreased the pain threshold in all three behavioral tests. Combined exercise with hawthorn consumption had the most statistically significant effect on Alzheimer's male rats' pain threshold in all three experiments. A combination of swimming endurance and resistance exercises with hawthorn consumption may modulate hyperalgesia in Alzheimer's rats. Future studies need to determine the effects of these factors on the treatment and/or management of painful conditions.


Sujet(s)
Maladie d'Alzheimer , Crataegus , Seuil nociceptif , Conditionnement physique d'animal , Animaux , Mâle , Maladie d'Alzheimer/physiopathologie , Maladie d'Alzheimer/thérapie , Maladie d'Alzheimer/induit chimiquement , Rats , Seuil nociceptif/effets des médicaments et des substances chimiques , Conditionnement physique d'animal/physiologie , Extraits de plantes/pharmacologie , Natation , Modèles animaux de maladie humaine , Rat Sprague-Dawley
8.
PLoS One ; 19(7): e0306320, 2024.
Article de Anglais | MEDLINE | ID: mdl-38968177

RÉSUMÉ

To achieve the accuracy and anti-interference of the motion control of the soft robot more effectively, the motion control strategy of the pneumatic soft bionic robot based on the improved Central Pattern Generator (CPG) is proposed. According to the structure and motion characteristics of the robot, a two-layer neural network topology model for the robot is constructed by coupling 22 Hopfield neuron nonlinear oscillators. Then, based on the Adaptive Neuro-Fuzzy Inference System (ANFIS), the membership functions are offline learned and trained to construct the CPG-ANFIS-PID motion control strategy for the robot. Through simulation research on the impact of CPG-ANFIS-PID input parameters on the swimming performance of the robot, it is verified that the control strategy can quickly respond to input parameter changes between different swimming modes, and stably output smooth and continuous dynamic position signals, which has certain advantages. Then, the motion performance of the robot prototype is analyzed experimentally and compared with the simulation results. The results show that the CPG-ANFIS-PID motion control strategy can output coupled waveform signals stably, and control the executing mechanisms of the pneumatic soft bionic robot to achieve biological rhythms motion propulsion waveforms, confirming that the control strategy has accuracy and anti-interference characteristics, and enable the robot have certain maneuverability, flexibility, and environmental adaptability. The significance of this work lies in establishing a CPG-ANFIS-PID control strategy applicable to pneumatic soft bionic robot and proposing a rhythmic motion control method applicable to pneumatic soft bionic robot.


Sujet(s)
Bionique , , Robotique , Robotique/méthodes , Robotique/instrumentation , Générateurs centraux de rythme/physiologie , Logique floue , Simulation numérique , Déplacement , Natation/physiologie , Algorithmes
9.
BMC Ecol Evol ; 24(1): 97, 2024 Jul 10.
Article de Anglais | MEDLINE | ID: mdl-38987674

RÉSUMÉ

BACKGROUND: The light organs of the splitfin flashlight fish Anomalops katoptron are necessary for schooling behavior, to determine nearest neighbor distance, and to feed on zooplankton under dim light conditions. Each behavior is coupled to context-dependent blink frequencies and can be regulated via mechanical occlusion of light organs. During shoaling in the laboratory individuals show moderate blink frequencies around 100 blinks per minute. In this study, we correlated bioluminescent blinks with the spatio-temporal dynamics of swimming profiles in three dimensions, using a stereoscopic, infrared camera system. RESULTS: Groups of flashlight fish showed intermediate levels of polarization and distances to the group centroid. Individuals showed higher swimming speeds and curved swimming profiles during light organ occlusion. The largest changes in swimming direction occurred when darkening the light organs. Before A. katoptron exposed light organs again, they adapted a nearly straight movement direction. CONCLUSIONS: We conclude that a change in movement direction coupled to light organ occlusion in A. katoptron is an important behavioral trait in shoaling of flashlight fish.


Sujet(s)
Natation , Animaux , Natation/physiologie , Luminescence , Poissons/physiologie , Comportement animal/physiologie
10.
PLoS One ; 19(7): e0305084, 2024.
Article de Anglais | MEDLINE | ID: mdl-38976706

RÉSUMÉ

To understand the locomotory mechanisms of flying and swimming animals, it is often necessary to develop assays that enable us to measure their responses to external gust perturbations. Typically, such measurements have been carried out using a variety of gusts which are difficult to control or characterize owing to their inherently turbulent nature. Here, we present a method of generating discrete gusts under controlled laboratory conditions in the form of a vortex rings which are well-characterized and highly controllable. We also provide the theoretical guidelines underlying the design of gust generators for specific applications. As a case study, we tested the efficacy of this method to study the flight response of freely-flying soldier flies Hermetia illucens. The vortex ring based method can be used to generate controlled gusts to study diverse phenomena ranging from a natural flight in insects to the artificial flight of insect-sized drones and micro-aerial vehicles.


Sujet(s)
Vol animal , Animaux , Vol animal/physiologie , Diptera/physiologie , Natation/physiologie
11.
PeerJ ; 12: e17708, 2024.
Article de Anglais | MEDLINE | ID: mdl-39006016

RÉSUMÉ

Background: An increase in training intensity could create changes in psychological and physiological variables in competitive athletes. For this reason, it is very relevant to know how an intensive training block could influence psychological variables in competitive swimmers. This study examined the effect of an intensive training block (HIT) for 2 weeks on the anxiety state and swimming performance compared to standard aerobic training. Methods: Twenty-two male competition swimmers were randomly assigned to two groups: HIT group (n = 11; age = 16.5 ± 0.29 years) and control group following the standard training program (n = 11; age = 16.1 ± 0.33 years). Psychological status variables (cognitive anxiety, somatic anxiety and self-confidence) and swimming performance (100-m front crawl) were measured pre-and post-test. Results: A significant effect of time was found for all psychological variables and swimming performance (F ≥ 17.6; p < 0.001; d ≥ 0.97). Furthermore, a significant group × time interaction effect was found in cognitive (F = 14.9; p < 0.001; d = 0.62) and somatic anxiety (F = 5.37; p = 0.031; d = 0.55) were found. Only a significant group effect was found in somatic anxiety (F = 27.1; p < 0.001; d = 1.2). Post hoc comparison revealed that both groups increased their cognitive anxiety and swimming performance, and decreased their self-confidence from pre to post test. However, cognitive anxiety increase significantly more in the HIT group compared to the control group. Furthermore, only the HIT training group significantly increased somatic anxiety over time, while somatic anxiety did not change significantly over time in the control group. Conclusion: Our findings indicated that a sudden increase in training intensity increased state anxiety more than standard training, but both conditions similarly enhanced swimming performance. Although the current level of psychological state is not affecting swimming performance negatively over this period, it should be regularly monitored by psychologists as it over a longer training period perhaps could have a negative influence on swimming performance.


Sujet(s)
Anxiété , Performance sportive , Natation , Humains , Natation/psychologie , Mâle , Anxiété/psychologie , Performance sportive/psychologie , Performance sportive/physiologie , Adolescent , Athlètes/psychologie , Concept du soi
12.
Nutrients ; 16(13)2024 Jun 27.
Article de Anglais | MEDLINE | ID: mdl-38999796

RÉSUMÉ

This study explored the impact of varying energy availability (EA) on the 24-h interstitial fluid glucose concentration (IGC) in five elite male Japanese triathletes at a training camp. Measurements of IGC, energy and macronutrient intake, and exercise energy expenditure (EEE) through metabolic equivalents (METs) from training logs were conducted. Three subjects were evaluated over two 4-day periods, and two subjects over one 4-day period. Findings revealed significant correlations of daily mean nocturnal IGC with daily EA (r = 0.553, p = 0.001) and energy intake (EI) (r = 0.595, p < 0.001). However, no significant correlation was found between mean daily nocturnal IGC and EEE (r = -0.278, p = 0.124). Daytime IGC was ≥110 mg/dL for >50% of the time in all subjects, except on 1 day in one subject, and never fell <70 mg/dL. Therefore, daily EA may influence nocturnal IGC in elite male triathletes, although high daytime IGC levels were maintained without hypoglycemia.


Sujet(s)
Athlètes , Ration calorique , Métabolisme énergétique , Liquide extracellulaire , Humains , Mâle , Liquide extracellulaire/métabolisme , Adulte , Métabolisme énergétique/physiologie , Glucose/métabolisme , Japon , Natation/physiologie , Jeune adulte , Glycémie/métabolisme , Peuples d'Asie de l'Est
13.
Zhonghua Liu Xing Bing Xue Za Zhi ; 45(7): 963-968, 2024 Jul 10.
Article de Chinois | MEDLINE | ID: mdl-39004968

RÉSUMÉ

Objective: To understand the epidemiological characteristics of fatal drowning in children in Zhejiang Province in 2022, analyze factors such as the swimming ability of children, the caregiver behavior at drowning site, types of first aid personnel and methods of first aid of unintentional fatal drowning and provide evidence for targeted intervention. Methods: Using the "Survey Form of Fatal Drowning Case in Children" designed by National Center for Chronic and Non-communicable Disease Control and Prevention of the China CDC, we collected case information of children aged 0-17 years who died due to drowning in Zhejiang in 2022 from medical history/death investigation records, telephone interviews, and home visits. Results: A total of 341 fatal drowning cases in children occurred in Zhejiang in 2022 and 330 cases were investigated (96.77%). The male to female of the cases was 2.33∶1, most cases were aged 15-17 years and 0-4 years, and 54.24% of fatal drowning cases occurred in children from other provinces. In the drowning cases, 83.33% were unintentional ones, and the proportion of intentional fatal drowning cases in children increased with age. Fatal drowning cases mainly occurred in open natural water bodies and public water storage facilities. More fatal drowning cases occurred in open natural water bodies in older children, while more fatal drowning cases occurred in public water storage facilities in younger children. In 275 children who died due to unintentional drowning, 73.09% could not swim, and only 1.09% were fully supervised by adults within an arm's length. First aid personnel, mainly medical staffs, bystanders and adult caregivers, were present for 47.63% fatal drowning cases. The proportion of the cases who had cardiopulmonary resuscitation as the first aid within 5 minutes was 2.18%. Conclusions: Drowning poses a serious threat to children's lives and there are differences in reasons and locations of fatal drowning in children in different age groups in Zhejiang Province in 2022. It is necessary to conduct to interventions to improve children's swimming skills, strengthen effective adult care and conduct health education about field first aid of drowning to reduce the incidence of drowning and related deaths in children.


Sujet(s)
Noyade , Humains , Noyade/mortalité , Noyade/épidémiologie , Adolescent , Enfant , Enfant d'âge préscolaire , Femelle , Mâle , Nourrisson , Chine/épidémiologie , Premiers secours , Nouveau-né , Natation
14.
Sci Am ; 330(6): 16, 2024 Jun 01.
Article de Anglais | MEDLINE | ID: mdl-39017558
15.
J Safety Res ; 89: 181-189, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38858041

RÉSUMÉ

PURPOSE: Drowning is 1 of the 10 leading causes of death due to unintentional injuries in children and adolescents worldwide. Knowing how to swim has been traditionally associated with water safety. However, its conceptualization may vary across studies, leading to different measurements and effects on the risk of drowning. This review sought to understand the current state of scientific evidence associating both issues. OBJECTIVES: To identify conceptualizations of knowing how to swim and to analyze the evidence indicating whether "knowing how to swim" may be a protective or a risk factor for unintentional drowning in children aged 10 to 14 years. METHOD: A systematic review of observational etiology studies was conducted, considering original peer-reviewed research published up to the year 2020. Databases including PubMed, Cochrane Central, Tripdatabase, Science Direct, Epistemonikos, Bvs and Bireme were searched for studies associating swimming skills as a risk or a protective factor for drowning (10-14 years). Study quality was assessed, and quantitative data were synthesized (without performing a meta-analysis). RESULTS: A total of 6,508 results were identified, with only 6 studies meeting the criteria for inclusion in the final cohort. It was evidenced that the exclusive possession of swimming skills, without a concurrent understanding of water safety, is associated with increased exposure to aquatic environments. Consequently, this may increase the risk of drowning. CONCLUSIONS: Among children aged 10 to 14 years, there is insufficient evidence regarding whether knowing how to swim serves as a protective factor against drowning compared to not knowing how to swim. PRACTICAL APPLICATIONS: The insufficiency of evidence and a lack of consensus in the conceptualization of swimming as a form of knowledge underscores the need for further research. Such research is crucial for informing investments in drowning prevention interventions, particularly during early adolescence.


Sujet(s)
Noyade , Natation , Humains , Enfant , Adolescent , Noyade/prévention et contrôle , Facteurs de risque
16.
Front Public Health ; 12: 1410707, 2024.
Article de Anglais | MEDLINE | ID: mdl-38883199

RÉSUMÉ

This study aimed to explore the potential effects of 8-week parents-accompanied swimming on the physical capacity and intelligence of preschool children in China. Thirty-six boys (mean age 3.56 ± 0.27 years) were divided into three groups: the traditional physical exercise group (TP, n = 12), the accompanied swimming group (AS, n = 12) and the independent swimming group (IS, n = 12). Participants' physical capacity was assessed before and after the intervention using the following indicators: height, weight, distance of tennis ball throw, standing long jump distance, time for the 10-meter shuttle run, time for a two-legged continuous jump, sit-and-reach distance, and time on the walking balance beam. Intelligence was assessed at three points: pre-test, mid-test after 4 weeks, and post-test. Data were analyzed using a two-way repeated measures ANOVA, Bonferroni test (p < 0.05) and effect size. The time of the AS and IS groups to walk the balance beam was significantly lower than the TP group, with a difference of 1.81 s (p < 0.01, [95% CI -3.22 to -0.40], ES = 1.53) and 1.25 s (p < 0.05, [95% CI -2.66 to 0.16], ES = 0.81). At the mid-test, the IQ scores of the TP group were lower than the AS group (p < 0.05, [95% CI -12.45 to -0.96], ES = 0.89). Additionally, at post-test, the IQ scores of the TP group were significantly lower than those of both AS (p < 0.01, [95% CI -14.12 to -2.74], ES = 1.15) and IS groups (p < 0.01, [95% CI -12.53 to -3.31], ES = 1.21). Swimming enhances children's balance and IQ scores more than traditional physical exercises. Involving parents in swimming leads to a more significant increase in IQ scores within 4 weeks of initial swimming exercise.


Sujet(s)
Intelligence , Parents , Natation , Humains , Mâle , Enfant d'âge préscolaire , Intelligence/physiologie , Natation/physiologie , Chine , Parents/psychologie , Exercice physique , Aptitude physique/physiologie
17.
J Strength Cond Res ; 38(7): 1295-1299, 2024 Jul 01.
Article de Anglais | MEDLINE | ID: mdl-38900175

RÉSUMÉ

ABSTRACT: Hill, V, Patterson, S, Buckthorpe, M, and Legg, HS. The acute effects of a preload upper-body power exercise on 50-m freestyle performance in youth swimmers. J Strength Cond Res 38(7): 1295-1299, 2024-This study aimed to investigate the acute effects of a medicine ball slam and the optimal recovery time required to induce a postactivation performance enhancement (PAPE) response on 50-meter freestyle swimming performance. Twenty-four (13 female, 11 male) competitive, adolescent swimmers (mean ± SD: age, 16.7 ± 1.2 years; height, 173.3 ± 6.7 cm; mass, 63.1 ± 6.4 kg) participated in a randomized crossover study. After the PAPE intervention (3 × 5 medicine ball slams), subjects had 1-minute, 4-minute, and 8-minute recovery periods before a 50-m maximal freestyle swim. A 1-way repeated-measures ANOVA revealed that different recovery times elicited changes in 50-m performance (F = 12.12, p < 0.0005). After 4 minutes of recovery, 50-m performance was 1.6% (0.47 seconds) faster (95% confidence interval [CI] [0.17-0.77], p < 0.001). When the data were split by sex, after 4 minutes of recovery, 50-m performance was 2% (0.64 seconds) faster for women (95% CI [0.279-0.998], p < 0.001). In conclusion, an upper-body power exercise, before performance, can induce a PAPE response and enhance 50-m freestyle performance after a 4-minute recovery period.


Sujet(s)
Performance sportive , Études croisées , Natation , Humains , Natation/physiologie , Femelle , Adolescent , Mâle , Performance sportive/physiologie , Membre supérieur/physiologie , Entraînement en résistance/méthodes , Force musculaire/physiologie
18.
Sci Rep ; 14(1): 12826, 2024 06 04.
Article de Anglais | MEDLINE | ID: mdl-38834813

RÉSUMÉ

Lamin A/C gene (LMNA) mutations contribute to severe striated muscle laminopathies, affecting cardiac and skeletal muscles, with limited treatment options. In this study, we delve into the investigations of five distinct LMNA mutations, including three novel variants and two pathogenic variants identified in patients with muscular laminopathy. Our approach employs zebrafish models to comprehensively study these variants. Transgenic zebrafish expressing wild-type LMNA and each mutation undergo extensive morphological profiling, swimming behavior assessments, muscle endurance evaluations, heartbeat measurement, and histopathological analysis of skeletal muscles. Additionally, these models serve as platform for focused drug screening. We explore the transcriptomic landscape through qPCR and RNAseq to unveil altered gene expression profiles in muscle tissues. Larvae of LMNA(L35P), LMNA(E358K), and LMNA(R453W) transgenic fish exhibit reduced swim speed compared to LMNA(WT) measured by DanioVision. All LMNA transgenic adult fish exhibit reduced swim speed compared to LMNA(WT) in T-maze. Moreover, all LMNA transgenic adult fish, except LMNA(E358K), display weaker muscle endurance than LMNA(WT) measured by swimming tunnel. Histochemical staining reveals decreased fiber size in all LMNA mutations transgenic fish, excluding LMNA(WT) fish. Interestingly, LMNA(A539V) and LMNA(E358K) exhibited elevated heartbeats. We recognize potential limitations with transgene overexpression and conducted association calculations to explore its effects on zebrafish phenotypes. Our results suggest lamin A/C overexpression may not directly impact mutant phenotypes, such as impaired swim speed, increased heart rates, or decreased muscle fiber diameter. Utilizing LMNA zebrafish models for drug screening, we identify L-carnitine treatment rescuing muscle endurance in LMNA(L35P) and creatine treatment reversing muscle endurance in LMNA(R453W) zebrafish models. Creatine activates AMPK and mTOR pathways, improving muscle endurance and swim speed in LMNA(R453W) fish. Transcriptomic profiling reveals upstream regulators and affected genes contributing to motor dysfunction, cardiac anomalies, and ion flux dysregulation in LMNA mutant transgenic fish. These findings faithfully mimic clinical manifestations of muscular laminopathies, including dysmorphism, early mortality, decreased fiber size, and muscle dysfunction in zebrafish. Furthermore, our drug screening results suggest L-carnitine and creatine treatments as potential rescuers of muscle endurance in LMNA(L35P) and LMNA(R453W) zebrafish models. Our study offers valuable insights into the future development of potential treatments for LMNA-related muscular laminopathy.


Sujet(s)
Animal génétiquement modifié , Carnitine , Créatine , Lamine A , Muscles squelettiques , Mutation , Danio zébré , Animaux , Lamine A/génétique , Lamine A/métabolisme , Muscles squelettiques/métabolisme , Muscles squelettiques/anatomopathologie , Muscles squelettiques/effets des médicaments et des substances chimiques , Créatine/métabolisme , Carnitine/métabolisme , Modèles animaux de maladie humaine , Laminopathies/génétique , Laminopathies/métabolisme , Natation , Transcriptome , Humains
19.
PLoS Biol ; 22(6): e3002501, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38843284

RÉSUMÉ

The ecological and evolutionary benefits of energy-saving in collective behaviors are rooted in the physical principles and physiological mechanisms underpinning animal locomotion. We propose a turbulence sheltering hypothesis that collective movements of fish schools in turbulent flow can reduce the total energetic cost of locomotion by shielding individuals from the perturbation of chaotic turbulent eddies. We test this hypothesis by quantifying energetics and kinematics in schools of giant danio (Devario aequipinnatus) and compared that to solitary individuals swimming under laminar and turbulent conditions over a wide speed range. We discovered that, when swimming at high speeds and high turbulence levels, fish schools reduced their total energy expenditure (TEE, both aerobic and anaerobic energy) by 63% to 79% compared to solitary fish (e.g., 228 versus 48 kj kg-1). Solitary individuals spend approximately 22% more kinematic effort (tail beat amplitude•frequency: 1.7 versus 1.4 BL s-1) to swim in turbulence at higher speeds than in laminar conditions. Fish schools swimming in turbulence reduced their three-dimensional group volume by 41% to 68% (at higher speeds, approximately 103 versus 33 cm3) and did not alter their kinematic effort compared to laminar conditions. This substantial energy saving highlights that schooling behaviors can mitigate turbulent disturbances by sheltering fish (within schools) from the eddies of sufficient kinetic energy that can disrupt locomotor gaits. Therefore, providing a more desirable internal hydrodynamic environment could be one of the ecological drivers underlying collective behaviors in a dense fluid environment.


Sujet(s)
Métabolisme énergétique , Natation , Animaux , Natation/physiologie , Métabolisme énergétique/physiologie , Phénomènes biomécaniques , Comportement animal/physiologie , Locomotion/physiologie , Cyprinidae/physiologie , Hydrodynamique , Comportement social
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