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1.
Sports Biomech ; : 1-13, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39145738

RESUMEN

Successful performance in competitive swimming requires a swimmer to maximise propulsion and minimise drag, which can be assessed using instantaneous swimming velocity. Many systems exist to quantify velocity, and therefore, it is important to understand the agreement between systems. This study examined the agreement between an automated video-based system and a tethered system to measure instantaneous velocity. Twenty-two competitive swimmers (state level or higher) completed 25 m of each stroke at maximal intensity. The tethered speedometer was attached to the swimmer's waist, while videos of each trial were recorded. The swimmer's head was then automatically tracked using proprietary software, and instantaneous velocity was determined from each system. Bland-Altman plots showed good agreement between the two systems in backstroke (95% Limits of Agreement (LOA): -0.24-0.26 m.s-1) and freestyle (95% LOA: -0.36-0.38 m.s-1) but poorer agreement in butterfly (95% LOA: -0.51-0.53 m.s-1) and breaststroke (95% LOA: -0.88-0.92 m.s-1). The root mean square error was higher in butterfly (0.27 m.s-1) and breaststroke (0.46 m.s-1) compared to backstroke (0.13 m.s-1) and freestyle (0.19 m.s-1). Results demonstrated that the two systems are comparable for measuring instantaneous swimming velocity; however, larger discrepancies are evident for butterfly and breaststroke.

2.
J Funct Morphol Kinesiol ; 9(3)2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39189214

RESUMEN

The aim of this study was to compare swimming speed and speed fluctuations in front crawl between swimmers of different performance levels using discrete variables against statistical parametric mapping (SPM). The sample was composed of 34 male swimmers divided into three groups: (i) group #1-recreational swimmers; (ii) group #2-competitive swimmers aged 12 to 14 years; (iii) group #3-competitive swimmers aged 15 to 17 years. Swimming speed and speed fluctuations (calculated based on four different conditions) were used as discrete variables. Using these discrete variables, ANOVA one-way was used to verify differences between groups, and Bonferroni post-hoc correction for pairwise comparison whenever suitable. SPM (with similar statistical tests) was used to analyze the swimming speed and fluctuation as a continuous variable. Overall, both statistical approaches revealed significant differences (p < 0.001) in swimming speed and speed fluctuations. However, as discrete variables (in four different conditions), the speed fluctuation was not able to detect significant differences between groups #2 and #3. Conversely, SPM was more sensitive and did yield significant differences between these two groups. Therefore, researchers and coaches should be aware that the speed fluctuation as a discrete variable may not identify differences in swimming speed fluctuations when the average value between groups is marginal. On the other hand, SPM was more sensitive in analyzing all groups.

3.
Front Physiol ; 15: 1406518, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39129754

RESUMEN

Background: Resistance training is often a part of the routine training regimen for competitive swimmers. However, due to the variety of resistance training methodology, the results can be inconsistent and sometimes unsatisfactory. Clear recommendations are still lacking at present. Aims: 1) Quantify the impact of resistance training on swimmers' upper limb maximum strength, front crawl performance and key technical parameters; 2) Find out the key technical parameters for improving front crawl performance-stroke rate or length; 3) Through subgroup analysis determine the best methodology of resistance training to enhance the front crawl. Methods: Systematic search in the PubMed, Embase, and Web of Science databases. Meta-analyses using the inverse-variance are performed to compare swimmers' upper limb maximum strength, front crawl performance and key technical parameters in resistance training and habitual aquatic training. A subgroup analysis was performed to examine whether the results were affected by the methodology of resistance training. Results: Thirteen studies (267 competitive swimmers) met the inclusion criteria. The results of meta-analysis showed that resistance training significantly improved upper limbs maximum muscle strength, and 25, 50, 100, and 200 m front crawl performance in competitive swimmers. And improvements in swimming performance may simply resulted from resistance training increasing stroke rate rather than stroke length. In addition, the results of subgroup analysis showed that only concurrent resistance training (CRT) and power training (PT) ultimately improved swimming performance by increasing the maximum muscle strength of the upper limbs. Conclusion: Resistance training significantly enhances competitive swimmers' upper limb strength and front crawl performance across various distances. The improvement in performance is likely attributed to an increased stroke rate rather than stroke length. In addition, CRT and PT are particularly effective, indicating the importance of selecting the appropriate methodology of resistance training for optimal swimming performance enhancement. Systematic review registration: https://doi.org/10.17605/OSF.IO/3JEGW.

4.
J Hum Kinet ; 93: 53-68, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39132430

RESUMEN

This study aimed to evaluate the effects of a five-week training program on undulatory underwater swimming (UUS) in swimmers and to compare the specific effects prompted by two different training protocols on UUS performance and kinematics. Swimmers (n = 14) were divided into in-water only (WO) (18.61 ± 2.62 years, FINA points: 507 ± 60) and water + dry-land training groups (with conical pulleys) (WD) (18.38 ± 2.67 years, FINA points: 508 ± 83). Three countermovement jumps (CMJ) and three maximal UUS trials were performed before and after a five-week training period. The training program comprised 14 × 30-min sessions. The WO group repeated the same 15-min block twice, while the WD group performed one block of 15 min in the water and the other block on land performing lower limb exercises with conical pulleys. Seven body landmarks were auto-digitalized during UUS by a pre-trained neural network and 21 kinematic variables were calculated. The level of statistical significance was set at p < 0.05. Significant time × group interaction in favour of the WD group was observed for mean vertical toe velocity (p = 0.035, η p 2 = 0.32). The WD group experienced enhancements in mean and maximum underwater velocity, kick frequency, maximum shoulder angular velocity, as well as mean and maximum vertical toe velocity (p < 0.05). The WO group exhibited an enhancement in CMJ height (p < 0.05). In conclusion, UUS performance was improved in adolescent swimmers after five weeks of specific training, only when combining water and conical pulley exercises. Coaches should include dry-land specific lower limb exercises in addition to in-water training to improve UUS performance.

5.
ACS Appl Mater Interfaces ; 16(31): 41450-41460, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39042714

RESUMEN

Microscale swimmers are attractive for targeted drug delivery, noninvasive microsurgery and environmental remediation at different length scales, among which, Marangoni-based swimmers have garnered considerable attention due to their independence of external energy supply. However, applications of most existing chemical swimmers are limited by complex fabrication, high cost, utilization of organic (or even toxic) solvents, poor motility performance, and lack of controllability. To address these challenges, we propose an approach for all-aqueous soft milli-swimmers that utilizes biodegradable hydrogels and biocompatible fuels. This innovative method achieves swimmer body generation and fuel loading in one step by simply dripping one aqueous solution into another, saving fabrication time and minimizing fuel loss during transfer. These all-aqueous soft milli-swimmers have rove beetle-like self-propulsion, which stores low-surface-energy compounds within their body for propulsion on liquid surfaces. Isotropic and anisotropic all-aqueous soft milli-swimmers are formed with precise control over their dimension, morphology, and movement velocity. Through their motion within engineered channels, intricate labyrinths, dynamic air-liquid interfaces, and collective self-assemblies, their remarkable adaptability in complex aqueous environments is demonstrated. Furthermore, the integration of functional nanoparticles endows these all-aqueous milli-swimmers with multifunctionality, expanding their applications in cargo transportation, sensing, and environmental remediation.

6.
J Clin Med ; 13(13)2024 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-38999388

RESUMEN

Objective: This study aimed to assess the relative and absolute intra- and inter-rater reliability of supraspinatus tendon (SST) thickness. Materials: Thirty adolescent swimmers with supraspinatus (SS) tendinopathy (n = 15) and a control-matched group (n = 15) were evaluated. Tendon thickness was measured according to four different measure procedures, i.e., (1) at 15 mm, (2) at 10, 20, and 30 mm, (3) at 10, 15, and 20 mm, and (4) 5 and 10 mm lateral to the most hyperechogenic reference point of the biceps tendon. Each examiner took two US images for the test measurements with a 10 min rest period. After 30 min, the subjects underwent retest measurements that were also repeated 1 week later. Results: SST thickness was greater in swimmers with SS tendinopathy compared with the matched control group for each procedure and rater (p < 0.001). Intra- and inter-rater reliability was good to excellent (ICC2.3: 0.78-0.98 and 0.83-0.97, respectively) in both groups. The lowest intra- and inter-rater reliability was found in procedures no. 2 and 4 (ICC2.3: 0.78 and 0.83). However, procedure no. 3 was the most reliable with the lowest error rate (ICC2.3: 0.92-0.97; SEM: 0.05-0.10 mm; MDC: 0.14-0.28 mm). Conclusions: The study confirmed the diagnostic value of ultrasound in SS tendinopathy. A multiple-reference-point procedure including a simple methodology (10, 15, and 20 mm from biceps tendon), was defined as the most reliable, expressed by the highest intra- and inter-rater ICCs.

7.
Scand J Med Sci Sports ; 34(8): e14702, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39044665

RESUMEN

This study aimed to compare performance, kinematic, and physiological variables between open water and pool swimming conditions in elite triathletes and to examine the associations between conditions on these variables. Fourteen elite triathletes (10 males and 4 females [23.4 ± 3.8 years]) performed two 1500-m swimming tests in open water and in a 25-m pool. Swimming speed, stroke rate (SR), length (SL) and index (SI), heart rate (HR), blood lactate concentrations [La-], and end-exercise oxygen uptake (EEV̇O2) were assessed in both conditions. Lower SL and SI and higher SR were obtained in open water compared with pool swimming (p < 0.05). Moreover, kinematic variables changed as a function of distance in both conditions (p < 0.05). No differences were found in the main physiological variables (HR, [La-], and EEV̇O2) between conditions. Respiratory exchange ratio presented lower values in open water than in pool conditions (p < 0.05), while time constant was higher in open water (p = 0.032). The fastest triathletes in open water obtained the best performance in the pool (r = 0.958; p < 0.001). All kinematic variables, HR and peak [La-] presented positive associations between conditions (r > 0.6; p < 0.05). Despite physiological invariance, triathletes and coaches should monitor specific open water training to adapt their swimming technique to the competitive environment.


Asunto(s)
Rendimiento Atlético , Frecuencia Cardíaca , Ácido Láctico , Consumo de Oxígeno , Natación , Agua , Humanos , Natación/fisiología , Masculino , Femenino , Rendimiento Atlético/fisiología , Frecuencia Cardíaca/fisiología , Adulto Joven , Consumo de Oxígeno/fisiología , Adulto , Ácido Láctico/sangre , Fenómenos Biomecánicos , Piscinas
8.
J Sports Sci ; : 1-9, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38922324

RESUMEN

The study examined acute effects of dryland muscular endurance (ME) and maximum strength (MS) sessions on performance, physiological, and biomechanical variables during a subsequent sprint swimming session. Twenty-seven swimmers (16.5 ± 2.6 yrs) completed three experimental conditions including: i) ME, 55% of 1-repetition maximum, ii) MS, 90% of 1-repetition maximum, and iii) control (CON, no dry-land). Twenty minutes following ME, MS and CON sessions swimmers performed a 10-s tethered swimming sprint, four by 50-m (4 × 50-m), and a 100-m front crawl sprints. Performance time, blood lactate, heart rate (HR), stroke rate (SR), stroke length (SL), stroke index (SI), and stroke efficiency (ηF) were measured during 4 × 50-m and 100-m. Hand grip strength (HG), and shoulder muscles isometric strength (ISO) were measured after each session. Mean 4 × 50-m time increased in ME compared to CON by 1.7 ± 2.7% (p = 0.01), while 100-m time was similar among conditions (p > 0.05). ISO was lower after dry-land training in all conditions (p = 0.01). Tethered force, HG, HR, SR, SL, SI, and ηF were no different between conditions (p > 0.05). Dryland ME session decrease swimming performance; however, ME and MS sessions did not affect technical ability during a subsequent maximum intensity swimming.

9.
Angew Chem Int Ed Engl ; 63(37): e202408198, 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-38924323

RESUMEN

An electromagnet is a particular device that takes advantage of electrical currents to produce concentrated magnetic fields. The most well-known example is a conventional solenoid, having the form of an elongated coil and creating a strong magnetic field through its center when it is connected to a current source. Spontaneous redox reactions located at opposite ends of an anisotropic Janus swimmer can effectively mimic a standard power source, due to their ability to wirelessly generate a local electric current. Herein, we propose the coupling of thermodynamically spontaneous redox reactions occurring at the extremities of a hybrid Mg/Pt Janus swimmer with a solenoidal geometry to generate significant magnetic fields. These chemically driven electromagnets spontaneously transform the redox-induced electric current into a magnetic field with a strength in the range of µT upon contact with an acidic medium. Such on-board magnetization allows them to perform compass-like rotational motion and magnetotactic displacement in the presence of external magnetic field gradients, without the need of using ferromagnetic materials for the swimmer design. The torque force experienced by the swimmer is proportional to the internal redox current, and by varying the composition of the solution, it is possible to fine-tune its angular velocity.

10.
Sports (Basel) ; 12(6)2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38921834

RESUMEN

Diver training improves physical and mental fitness, which can also benefit other sports. This study investigates the effect of eight weeks of static apnea training on maximum apnea time, and on the physiological parameters of runners, swimmers, and sedentary participants, such as forced vital capacity (FVC), minimum heart rate (HR), and oxygen saturation (SpO2). The study followed 19 participants, including five runners, swimmers, sedentary participants, and four competitive divers for reference values. The minimum value of SpO2, HR, maximum duration of apnea, and FVC were measured. Apnea training occurred four times weekly, consisting of six apneas with 60 s breathing pauses. Apnea duration was gradually increased by 30 s. The measurement started with a 30 s apnea and ended with maximal apnea. There was a change in SpO2 decreased by 6.8%, maximum apnea length increased by 15.8%, HR decreased by 9.1%, and FVC increased by 12.4% for the groups (p < 0.05). There were intra-groups changes, but no significant inter-groups difference was observed. Eight weeks of apnea training improved the maximum duration of apnea, FVC values and reduced the minimum values of SpO2 and HR in all groups. No differences were noted between groups after training. This training may benefit cardiorespiratory parameters in the population.

11.
Front Nutr ; 11: 1381801, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38807642

RESUMEN

This cross-sectional study aims to explore the relationships between food habits, perceived barriers to healthy eating, and sports nutrition knowledge among adolescent swimmers. The study focuses on understanding how these factors interact and influence dietary choices in young athletes. A cohort of 52 adolescent swimmers aged 12-18 from Al Hussein Youth Club in Al-Hussein Sport City participated in the study. Data were collected through surveys assessing food habits, perceived barriers to healthy eating, and sports nutrition knowledge. Pearson Correlation analysis was employed to examine associations between variables, and stepwise regression analysis was used to identify predictors of food habits. The analysis revealed a significant positive association between food habits and sports nutrition knowledge (r = 0.393, p = 0.004). Knowledge emerged as a significant positive predictor of food habits (ß = 0.393, p = 0.004), highlighting the influential role of sports nutrition knowledge in shaping the dietary choices of adolescent swimmers. However, the introduction of Barriers lacked significance, and individual predictors did not reach statistical significance. These findings underscore the importance of targeted interventions aimed at enhancing nutritional education among adolescent swimmers. Understanding the interplay between knowledge, barriers, and food habits provides valuable insights into the complex dynamics that influence the dietary choices of young athletes. Addressing these factors through tailored educational programs can promote healthier eating habits and optimize performance among adolescent swimmers. This study highlights the critical role of sports nutrition knowledge in shaping the dietary behaviors of adolescent swimmers. By addressing knowledge gaps and overcoming perceived barriers, targeted interventions can help improve food habits and enhance the overall health and performance of young athletes.

12.
Bioinspir Biomim ; 19(3)2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38569526

RESUMEN

Computational models are used to examine the effect of schooling on flow generated noise from fish swimming using their caudal fins. We simulate the flow as well as the far-field hydrodynamic sound generated by the time-varying pressure loading on these carangiform swimmers. The effect of the number of swimmers in the school, the relative phase of fin flapping of the swimmers, and their spatial arrangement is examined. The simulations indicate that the phase of the fin flapping is a dominant factor in the total sound radiated into the far-field by a group of swimmers. For small schools, a suitable choice of relative phase between the swimmers can significantly reduce the overall intensity of the sound radiated to the far-field. The relative positioning of the swimmers is also shown to have an impact on the total radiated noise. For a larger school, even highly uncorrelated phases of fin movement between the swimmers in the school are very effective in significantly reducing the overall intensity of sound radiated into the far-field. The implications of these findings for fish ethology as well as the design and operation of bioinspired vehicles are discussed.


Asunto(s)
Peces , Modelos Biológicos , Animales , Fenómenos Biomecánicos , Natación , Instituciones Académicas
13.
Adv Sci (Weinh) ; 11(25): e2308561, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38590131

RESUMEN

Underwater organisms exhibit sophisticated propulsion mechanisms, enabling them to navigate fluid environments with exceptional dexterity. Recently, substantial efforts have focused on integrating these movements into soft robots using smart shape-changing materials, particularly by using light for their propulsion and control. Nonetheless, challenges persist, including slow response times and the need of powerful light beams to actuate the robot. This last can result in unintended sample heating and potentially necessitate tracking specific actuation spots on the swimmer. To tackle these challenges, new azobenzene-containing photopolymerizable inks are introduced, which can be processed by extrusion printing into liquid crystalline elastomer (LCE) elements of precise shape and morphology. These LCEs exhibit rapid and significant photomechanical response underwater, driven by moderate-intensity ultraviolet (UV) and green light, being the actuation mechanism predominantly photochemical. Inspired by nature, a biomimetic four-lapped ephyra-like LCE swimmer is printed. The periodically illumination of the entire swimmer with moderate-intensity UV and green light, induces synchronous lappet bending toward the light source and swimmer propulsion away from the light. The platform eliminates the need of localized laser beams and tracking systems to monitor the swimmer's motion through the fluid, making it a versatile tool for creating light-fueled robotic LCE free-swimmers.

14.
Rev. int. med. cienc. act. fis. deporte ; 24(95): 1-15, mar.-2024. graf, tab
Artículo en Inglés | IBECS | ID: ibc-ADZ-331

RESUMEN

In sports science, genetic testing has become a valuable tool for understanding the genetic foundations of athletic ability. This study investigates whether genetic testing may be used to customize training plans for French swimmers to optimize performance, reduce injury risk, and improve recovery. Coaches can determine genetic predispositions pertaining to muscle composition, metabolism, injury risk, and recovery capacity by analyzing the genetic profile of an athlete. With the use of this data, individualized training plans that target deficiencies, build on strengths and increase success rates in the pool may be created. The research was based on primary data analysis to determine whether the research used Smart PLS software and generated results, including descriptive statistics, and correlation coefficient analysis, which also explains the smart PLS Algorithm Model between them. Event specialization, dietary optimization, injury avoidance, recovery optimization, talent discovery, and long-term athlete development are some of the main uses of genetic testing. French swimming programscan acquire a competitive advantage and set up their athletes for success on the international scene by incorporating genetic information into coaching procedures. A discussion of the ethical issues surrounding the use of genetic data in sports is included, focusing on the value of informed consent and private rights. The overall research found the positive and significant role of genetic testing in tailoring training programs for French swimmers. Genetic testing has great potential to enhance training regimens and bring forth the hidden talent of French swimmers, solidifying France's standing as a dominant force in the world of competitive swimming. (AU)


Asunto(s)
Humanos , Deportes Acuáticos , Pruebas Genéticas , Atletas , Rendimiento Atlético , Heridas y Lesiones , Francia
15.
Int. j. morphol ; 42(1): 82-85, feb. 2024. ilus, tab
Artículo en Inglés | LILACS | ID: biblio-1528837

RESUMEN

SUMMARY: Hand size is part of the anthropometric parameters that are assessed in swimmers to select elite athletes, as certain anthropometric relationships involving hand measurements are significantly correlated with sports performance in various swimming disciplines. The authors present the results of the anthropometric study carried out on the hands of 15 elite male Italian swimmers from to the Italian national open water swimming team. All swimmers participated at least once in World Cup and Absolute Italian Championships, winning at least one medal in their sporting career. In particular, the sample includes a medallist at the World Championships, a winner of the World Cup ultra swim marathon circuit and medallists at the European Championships. The sample consisted of 15 elite male swimmers with a mean age of 28.93 years. The following anthropometric measurements were taken on each athlete: Stature; weight; seven dimensions on each hand: hand length; hand breadth metacarpal; palm length; middle finger length; index finger length; thumb distance; and the distance from the thumb root to first flexure line of the index finger - trigger length. The size of the hands is an important factor in the swimmer's propulsion and push as a larger hand allows for greater support in the water and consequently generates more resistance. The anthropometric characteristics of the hands of Italian swimmers are missing from the anthropometric data already reported in the literature and can be used to make comparisons with elite athletes from other nations. Furthermore, anthropometric measurements could be used as predictors to estimate the swimmers' chance of success.


El tamaño de la mano es uno de los parámetros antropométricos que se evalúan en los nadadores para seleccionar a los deportistas de élite. Los autores presentan los resultados de un estudio antropométrico realizado en las manos de 15 nadadores italianos masculinos de élite pertenecientes al equipo nacional de natación en aguas abiertas. Todos los nadadores participaron al menos una vez en Copas del Mundo y Campeonatos de Italia, ganando al menos una medalla en su carrera deportiva. En concreto, la muestra incluye un medallista en los Campeonatos del Mundo, un ganador de la Copa del Mundo del circuito de ultra maratón de natación y medallistas en los Campeonatos de Europa. La muestra consta de 15 nadadores masculinos de élite con una edad media de 28,93 años. Se tomaron las siguientes medidas antropométricas a cada atleta: estatura; peso; siete dimensiones en cada mano: longitud de la mano, anchura de la mano en el metacarpiano, longitud de la palma, longitud del primer, segundo y tercer dedo, distancia entre la raíz del primer dedo y la primera línea de flexión del segundo dedo. El tamaño de las manos es un factor importante para la propulsión y el empuje del nadador, ya que una mano más grande permite un mayor apoyo en el agua y, en consecuencia, genera más resistencia. Las características antropométricas de las manos de los nadadores italianos faltan en los datos antropométricos recolectados en la literatura y pueden utilizarse para hacer comparaciones con los atletas de élite de otras naciones. Además, las medidas antropométricas podrían utilizarse como predictores para estimar las posibilidades de éxito de los nadadores.


Asunto(s)
Humanos , Masculino , Adulto , Natación , Antropometría , Mano/anatomía & histología , Italia
16.
Physiol Rep ; 12(1): e15890, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38195247

RESUMEN

Swimmer athletes showed a decreased ventilatory response and reduced sympathetic activation during peripheral hypoxic chemoreflex stimulation. Based on these observations, we hypothesized that swimmers develop a diminished cardiorespiratory coupling due to their decreased hypoxic peripheral response. To resolve this hypothesis, we conducted a study using coherence time-varying analysis to assess the cardiorespiratory coupling in swimmer athletes. We recruited 12 trained swimmers and 12 control subjects for our research. We employed wavelet time-varying spectral coherence analysis to examine the relationship between the respiratory frequency (Rf ) and the heart rate (HR) time series during normoxia and acute chemoreflex activation induced by five consecutive inhalations of 100% N2 . Comparing swimmers to control subjects, we observed a significant reduction in the hypoxic ventilatory responses to N2 in swimmers (0.012 ± 0.001 vs. 0.015 ± 0.001 ΔVE /ΔVO2 , and 0.365 ± 0.266 vs. 1.430 ± 0.961 ΔVE /ΔVCO2 /ΔSpO2 , both p < 0.001, swimmers vs. control, respectively). Furthermore, the coherence at the LF cutoff during hypoxia was significantly lower in swimmers compared to control subjects (20.118 ± 3.502 vs. 24.935 ± 3.832 area under curve [AUC], p < 0.012, respectively). Our findings strongly indicate that due to their diminished chemoreflex control, swimmers exhibited a substantial decrease in cardiorespiratory coupling during hypoxic stimulation.


Asunto(s)
Atletas , Hipoxia , Humanos , Frecuencia Cardíaca , Frecuencia Respiratoria , Factores de Tiempo
17.
J Sci Med Sport ; 27(3): 143-148, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38071136

RESUMEN

OBJECTIVES: To monitor individual mucosal immunity and identify potential risk factors of upper respiratory symptoms in elite swimmers over a competitive season. DESIGN: Eight-month longitudinal study, observing mucosal immunity, Epstein-Barr virus status, training loads and illness symptoms of elite international swimmers, leading into the Commonwealth Games 2018. METHODS: Participants were fourteen elite swimmers (age ±â€¯standard deviation = 19.9 ±â€¯0.8 years, height = 178.9 ±â€¯6.3 cm, and mass = 75.0 ±â€¯7.7 kg). Self-reported upper respiratory symptoms, training load and saliva samples were collected weekly. Venous blood samples were taken at study commencement to determine Epstein-Barr virus status. RESULTS: Throughout the study, 70 episodes of upper respiratory symptoms were recorded resulting in 34 days of missed training. Incidence (p = 0.001), severity (p = 0.022), and duration of upper respiratory symptoms (p = 0.001) were significantly higher during high training loads, compared to low. Eight swimmers (61 %) had evidence of past infection with Epstein-Barr virus, but this had no relationship with incidence, severity, or duration of upper respiratory symptoms (p > 0.05). Relative individual salivary immunoglobulin A concentration was 12 % lower when upper respiratory symptoms were present but was not statistically significant (p = 0.101). CONCLUSIONS: This study highlights the importance of individual athlete monitoring, to identify swimmers at increased illness risk. Identification of possible risk factors for upper respiratory symptoms, such as increased training load, may allow for modifications in training or other illness preventative strategies for elite swimmers.


Asunto(s)
Infecciones por Virus de Epstein-Barr , Natación , Humanos , Estudios Longitudinales , Monitorización Inmunológica , Herpesvirus Humano 4
18.
Front Physiol ; 14: 1260346, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38156067

RESUMEN

This study aimed to evaluate the test-retest reliability of a sprint performance test with semi-tethered front crawl swimming to indirectly assess the current potential to perform at maximal anaerobic effort in adolescent swimmers. Eight adolescent swimmers participated in this study (gender: females (n = 4) aged 13.0 ± 0.8 years, body height 1.6 ± 0.0 m, body mass 50.1 ± 4.5 kg; and males (n = 4) aged 13.3 ± 1.3 years, body height 1.7 ± 0.1 m, body mass 59.0 ± 8.2 kg. The testing protocol consisted of two trials of 25 m semi-tethered front crawl swimming with maximal effort and with 1 kg resisted isotonic load. Velocity data were recorded automatically by the 1080 Sprint device for 15 m (between 3 m and 18 m). The Fast Fourier Transform algorithm filtered raw instantaneous swimming velocity data in distance (time) function. A third-degree polynomial was used to extract the individual velocity profile, from which the following variables were chosen for test-retest reliability and the assessment of sprint performance: ttrial15, vmax, vmin, tvto max, tvat max, Dto vmax, Dat vmax, fatigue index. Parameters such as vmax, vmin, and ttrial15 were estimated from swimming velocity profiles and considered as reliable. The CV showed low variance <5%; while ICC2,1 demonstrated respectively good (ICC2,1: 0.88), very good (ICC2,1: 0.95), and excellent (ICC2,1: 0.98) rate of relative reliability; and the Bland-Altman index revealed an acceptable agreement (LoA ≤5%) between two measurements. The sprint performance test based on semi-tethered front crawl swimming confirmed that ttrial15, vmax, and vmin were reliable variables to indirectly indicate a potential to perform the maximal anaerobic effort among adolescent swimmers. The evaluation of the swimming velocity profiles allows coaches to monitor the adaptive changes of performance during the training process.

19.
Clin Oral Investig ; 27(12): 7777-7785, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37924355

RESUMEN

INTRODUCTION: Competitive swimmers spend considerable time practicing their sport. Prolonged exposure to chlorinated water can alter salivary parameters and might compromise oral health. This study aimed to determine erosive tooth wear status and its related risk factors among competitive swimmers as compared to non-swimmers. MATERIALS AND METHODS: A cross-sectional study consisting of 180 athletes (90 competitive swimmers versus 90 competitive rowers "non-swimmers") was conducted. Participants were interviewed on the common erosion risk factors. The Basic Erosive Wear Examination system was used to assess the status of erosive tooth wear. Stimulated saliva sample was collected before and after a training session and pool pH was evaluated using pH strips for 7 days. Data were analyzed using descriptive statistics and multivariable analysis. RESULTS: The prevalence of dental erosion was significantly higher among competitive swimmers (60%) with higher BEWE scores compared to non-swimmers (25.6%). The salivary flow rate was reduced significantly after training sessions in both groups while salivary pH increased among swimmers. Evaluation of pool water revealed a continuous reduction in the pH level, reaching a very acidic pH level of 3.24. CONCLUSION: Erosive tooth wear is more prevalent among competitive swimmers. Years of practice and regular consumption of acidic drinks increase the odds of developing erosive lesions. A high incidence of erosive lesions may be attributed to a reduction in swimming pool pH level. Salivary parameters showed variations between groups after training sessions.


Asunto(s)
Erosión de los Dientes , Desgaste de los Dientes , Humanos , Erosión de los Dientes/epidemiología , Erosión de los Dientes/etiología , Estudios Transversales , Egipto/epidemiología , Desgaste de los Dientes/epidemiología , Prevalencia , Ácidos , Agua
20.
Behav Sci (Basel) ; 13(10)2023 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-37887478

RESUMEN

This work analyses the motivational regulation, achievement goals and sport commitment of Spanish Masters swimmers, being the first study of its kind. A total of 211 (106 women and 105 men) Masters swimmers from the Federation of Castilla-La Mancha (Spain) aged between 20 and 74 participated. Each participant completed the Sport Motivation Scale (motivation regulation), the Achievement Goals Questionnaire for Sport (achievement goals) and the Sport Commitment Questionnaire (sport commitment), all validated for the Spanish population. A mixed rANOVA was performed to analyse the results, using sex and age group as covariates, and the different groupings of the sample (weekly training days, weekly training hours and practice of other sports) as between-participants factors. The results showed that the participants presented a predominantly intrinsic-integrated and identified regulation, rather than introjected and external regulation. Mastery goals were more prevalent than performance-approach and performance-avoidance goals. In addition, current sport commitment was high, being greater than future commitment. Pearson's correlation analysis showed moderate relationships between our variables. We found no influence of either the covariates of sex and age or the grouping variables. These findings serve as the basis for further study of the motivation of Masters swimmers in Spain.

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