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1.
PLoS One ; 15(9): e0239158, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32966338

RESUMO

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


Assuntos
Atletas , Desempenho Atlético/fisiologia , Ciclismo/fisiologia , Corrida/fisiologia , Natação/fisiologia , Adulto , Biomarcadores/sangue , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade
2.
PLoS One ; 15(8): e0227394, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32866148

RESUMO

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


Assuntos
Exercício Físico/fisiologia , Condicionamento Físico Humano/métodos , Natação/fisiologia , Desempenho Atlético/fisiologia , Fenômenos Biomecânicos , Terapia por Exercício , Humanos , Masculino , Força Muscular/fisiologia , Músculos , Polônia , Treinamento de Resistência/métodos , Adulto Jovem
3.
Artigo em Inglês | MEDLINE | ID: mdl-32867383

RESUMO

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


Assuntos
Desempenho Atlético/fisiologia , Tempo de Reação/fisiologia , Natação/fisiologia , Desempenho Atlético/psicologia , Fenômenos Biomecânicos/fisiologia , Humanos , Manutenção , Masculino
4.
PLoS One ; 15(8): e0238197, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32841286

RESUMO

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


Assuntos
Música , Natação/fisiologia , Esportes Aquáticos/fisiologia , Adolescente , Adulto , Braço/fisiologia , Desempenho Atlético/fisiologia , Fenômenos Biomecânicos , Feminino , Humanos , Perna (Membro)/fisiologia , Masculino , Destreza Motora/fisiologia , Movimento/fisiologia , Amplitude de Movimento Articular/fisiologia , Adulto Jovem
5.
PLoS One ; 15(8): e0236504, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32745109

RESUMO

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


Assuntos
Fenômenos Biomecânicos/fisiologia , Mergulho/fisiologia , Golfinhos/fisiologia , Natação/fisiologia , Animais , Braço/fisiologia , Humanos , Masculino , Movimento/fisiologia
6.
J Int Soc Sports Nutr ; 17(1): 40, 2020 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-32711541

RESUMO

BACKGROUND: Investigations of ß-alanine supplementation shows effects on metabolic (aerobic and anaerobic) participation and performance on swimming by a possible blood acidosis buffering. Considering this background, the objective of the present study was to analyze the effects of ß-alanine supplementation on metabolic contribution and performance during 400-m swim. METHODS: Thirteen competitive swimmers underwent a 6-week, double-blind placebo-controlled study, ingesting 4.8 g.day- 1 of ß-alanine or placebo. Before and after the supplementation period, the total anaerobic contribution (TAn) and 30-s all-out tethered swimming effort (30TS) were assessed. Anaerobic alactic (AnAl) and lactic energy (AnLa) was assumed as the fast component of excess post-exercise oxygen consumption and net blood lactate accumulation during exercise (∆[La-]), respectively. Aerobic contribution (Aer) was determined by the difference between total energy demand and TAn. In addition to conventional statistical analysis (Repeated measures ANOVA; p > 0.05), a Bayesian repeated measures ANOVA was used to evidence the effect probability (BFincl). RESULTS: No differences and effects were found between groups, indicating no supplementation effects. Repeated measures ANOVA, with confirmation of effect, was indicate reduce in ∆Lactate (p: 0.001; BFincl: 25.02); absolute AnLa (p: 0.002; BFincl: 12.61), fatigue index (p > 0.001; BFincl: 63.25) and total anaerobic participation (p: 0.008; BFincl: 4.89). CONCLUSIONS: Thus, the results demonstrated that all changes presented were evidenced as a result of exposure to the training period and ß-alanine supplementation doesn't affect metabolic contribution and performance during 400-m freestyle.


Assuntos
Desempenho Atlético/fisiologia , Suplementos Nutricionais , Ácido Láctico/sangue , Natação/fisiologia , beta-Alanina/administração & dosagem , Adolescente , Adulto , Cápsulas , Método Duplo-Cego , Feminino , Humanos , Masculino , Adulto Jovem
7.
Chemosphere ; 255: 127020, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32679633

RESUMO

The effect of methylmercury (MeHg) was investigated in glass eel migration behavior and metabolism. To migrate up estuary, glass eels synchronize their swimming activity to the flood tide and remain on or in the substratum during ebb tide. Following seven days of exposure to MeHg (100 ng L-1), glass eels migration behavior was expressed by their swimming synchronization to the water current reversal every 6.2 h (mimicking the alternation of flood and ebb tides) and their swimming activity level. In relation to their behavior, we then analyzed the energy-related gene expression levels in individual head, viscera and muscle. Results showed that MeHg decreased the number of glass eels synchronized to the change in water current direction and their swimming activity level. This last effect was more pronounced in non-synchronized fish than in synchronized ones, supporting the idea that non-synchronized glass eels could be more vulnerable to stress. As regard the expression of energy-related genes, no significant difference was observed between control and MeHg-exposed fish. In contrast, when the swimming activity levels were plotted against transcriptional responses, positive correlations were evidenced in viscera and especially in the head of exposed glass eels but not in control. Finally, it is noteworthy that non-synchronized glass eels displayed lower expression level of metabolism genes than their synchronized counterpart, but only in the head. Altogether, these results support the interest of focusing on the head to investigate the facultative migration behavior in glass eels and the effect of environmental stressors on this rhythmic behavior.


Assuntos
Anguilla/fisiologia , Compostos de Metilmercúrio/toxicidade , Poluentes Químicos da Água/toxicidade , Anguilla/metabolismo , Migração Animal/efeitos dos fármacos , Migração Animal/fisiologia , Animais , Estuários , Compostos de Metilmercúrio/metabolismo , Natação/fisiologia
8.
PLoS Biol ; 18(7): e3000462, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32697779

RESUMO

Most fish swim with body undulations that result from fluid-structure interactions between the fish's internal tissues and the surrounding water. Gaining insight into these complex fluid-structure interactions is essential to understand how fish swim. To this end, we developed a dedicated experimental-numerical inverse dynamics approach to calculate the lateral bending moment distributions for a large-amplitude undulatory swimmer that moves freely in three-dimensional space. We combined automated motion tracking from multiple synchronised high-speed video sequences, computation of fluid dynamic stresses on the swimmer's body from computational fluid dynamics, and bending moment calculations using these stresses as input for a novel beam model of the body. The bending moment, which represent the system's net actuation, varies over time and along the fish's central axis due to muscle actions, passive tissues, inertia, and fluid dynamics. Our three-dimensional analysis of 113 swimming events of zebrafish larvae ranging in age from 3 to 12 days after fertilisation shows that these bending moment patterns are not only relatively simple but also strikingly similar throughout early development and from fast starts to periodic swimming. This suggests that fish larvae may produce and adjust swimming movements relatively simply, yet effectively, while restructuring their neuromuscular control system throughout their rapid development.


Assuntos
Análise Numérica Assistida por Computador , Natação/fisiologia , Peixe-Zebra/fisiologia , Animais , Fenômenos Biomecânicos , Fertilização , Larva/fisiologia , Modelos Biológicos , Movimento (Física) , Cauda
9.
Artigo em Inglês | MEDLINE | ID: mdl-32486151

RESUMO

Pacing in swimming has been investigated in pool swimming for elite-standard and age group freestyle swimmers, but little is known about pacing in age group swimmers competing at world class level in backstroke, breaststroke, and butterfly. The aim of this study was to investigate pacing for age group swimmers competing at world class level in 100 and 200 m in the four single disciplines (freestyle, backstroke, breaststroke and butterfly). Data on 18,187 unique finishers competing in four FINA Master World Championships between 2014 and 2019 were analyzed. The sample included 3334 women and 14,853 men. Swimming speed decreased with increasing age (p < 0.05). Freestyle was the fastest and breaststroke the slowest (p < 0.05) stroke. Women and men were faster in 100 m (p < 0.05) than in 200 m. Backstroke was the stroke with the lowest and butterfly with the highest coefficient of variation in swimming speed. One hundred meters had a higher coefficient of variation in swimming speed than breaststroke (p < 0.05). For 100 m, swimming speed decreased for all strokes and all age groups during the second lap. For 200 m, swimming speed was the fastest for all strokes and all age groups during the first lap. In summary, the FINA World Masters Championships presented the unique characteristic that, when all competitors were considered, (i) swimming speed decreased with increasing age, (ii) women and men were faster in 100 m than in 200 m, (iii) freestyle was the fastest stroke and (iv) the largest increase in swimming time for 100 m all strokes and all age groups occurred during the second (out of two) lap and for 200 m, swimming speed was the fastest for all strokes and age groups during the first lap. These findings should help coaches to develop age- and event-tailored pacing strategies.


Assuntos
Desempenho Atlético/fisiologia , Comportamento Competitivo/fisiologia , Natação/fisiologia , Adulto , Desempenho Atlético/estatística & dados numéricos , Feminino , Humanos , Masculino , Natação/estatística & dados numéricos
10.
J Sports Sci ; 38(19): 2253-2263, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32573343

RESUMO

This study examined the swimming competence of primary school children, and how it was related to swimming activity, non-fatal aquatic events, and demographic factors. Primary school students (N = 4959; female = 2705, male = 2241; age range = 5 to 14 years) across 28 schools in the 15 districts of Hong Kong completed the Swimming Competence Questionnaire, and questions about their swimming experience, non-fatal aquatic events, and demographic variables. Descriptive statistics showed that over 60% of children could swim more than 5m, but less than 50% could swim over 25m. Over 50% of children were able to perform some basic swimming skills (e.g., holding breath underwater, floating, poolside/kickboard kicking, and treading water). Swimming competence was positively predicted by the demographic factors (i.e., age, sex, family income, and parents' highest education level), swimming experience, learning experience, and swimming location. Treading water was the only factor of swimming competence that established asignificant negative association with non-fatal aquatic events. Current results can be used to target key groups to improve children's swimming competence and reduce non-fatal aquatic events; children from lower socio-economic backgrounds and with less swimming experience should be encouraged to participate in more formal learn to swim lessons.


Assuntos
Destreza Motora/fisiologia , Natação/fisiologia , Adolescente , Fatores Etários , Criança , Afogamento/prevenção & controle , Escolaridade , Feminino , Hong Kong , Humanos , Renda , Aprendizagem , Masculino , Pais/psicologia , Fatores Sexuais , Natação/psicologia
11.
J Sports Sci ; 38(18): 2092-2099, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32475220

RESUMO

This study aimed to investigate swimmer's use and coach prescription of recovery strategies during training and competition while examining perceived challenges, barriers, and beliefs in the importance of their effectiveness. A mixed-methods sequential explanatory design was implemented. Thirty-seven male and 45 female sub-elite to elite swimmers (age 18 ± 3 y), and 4 male and 6 female coaches (age 40 ± 9 y) completed an online, 78-item recovery strategy survey. Swimmers and coaches responded to questions regarding when, why, and how they used recovery strategies, perceived challenges and barriers to strategy inclusion during training and competition. Data were coded and analysed thematically. Fisher's Exact Test was conducted on 5-point Likert scale responses. Most recovery strategies were used and prescribed more during competition. Swimmers reported active recovery as the most effective recovery strategy (44%), whereas coaches rated sleep or napping (40%). Swimmers and coaches perceived most recovery strategies to be more effective and important during competition than in training. Swimmers used, and coaches prescribed, recovery strategies more during the competition, highlighting the discrepancies in use between training and competition. Targeted education programmes should enhance athletes and coach's recovery knowledge and practical application of strategies, while accounting for individual sport and life demands.


Assuntos
Atletas/psicologia , Fadiga/prevenção & controle , Tutoria , Mialgia/prevenção & controle , Percepção , Natação/fisiologia , Natação/psicologia , Adolescente , Adulto , Temperatura Baixa , Comportamento Competitivo , Exercício de Arrefecimento , Feminino , Humanos , Hidroterapia , Imersão , Masculino , Fadiga Muscular , Condicionamento Físico Humano , Sono , Adulto Jovem
12.
J Sports Sci ; 38(20): 2307-2313, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32552507

RESUMO

Body composition can substantially impact elite swimming performance. In practice, changes in fat and lean mass of elite swimmers are estimated using body mass, sum of seven skinfolds (∑7) and lean mass index (LMI). However, LMI may be insufficiently accurate to detect small changes in body composition which could meaningfully impact swimming performance. This study developed equations which estimate dual-energy x-ray absorptiometry (DXA)-derived lean and fat mass using body mass and ∑7 data. Elite Australian swimmers (n = 44; 18 male, 26 female) completed a DXA scan and standardised body mass and ∑7 measurements. Equations to estimate DXA-derived lean and fat mass based on body mass, ∑7 and sex were developed. The relationships between ∑7, body mass and DXA-derived lean and fat mass were non-linear. Fat mass (Adjusted R2 = 0.91; standard error = 1.0 kg) and lean mass (Adjusted R2 = 0.99; standard error = 1.0 kg) equations were considered sufficiently accurate. Lean mass estimates outperformed the LMI in identifying the correct direction of change in lean mass (82% correct; LMI 71%). Using the accurate estimations produced by these equations will enhance the prescription and evaluation of programmes to optimise the body composition and subsequent performance in swimmers.


Assuntos
Distribuição da Gordura Corporal/estatística & dados numéricos , Índice de Massa Corporal , Pregas Cutâneas , Natação/fisiologia , Absorciometria de Fóton , Adolescente , Adulto , Desempenho Atlético/fisiologia , Austrália , Feminino , Humanos , Masculino , Análise de Regressão , Adulto Jovem
13.
Artigo em Inglês | MEDLINE | ID: mdl-32429560

RESUMO

Swimming exercise at sea level causes a transient decrease in lung diffusing capacity for carbon monoxide (DLCO). The exposure to hypobaric hypoxia can affect lung gas exchange, and hypoxic pulmonary vasoconstriction may elicit pulmonary oedema. The purpose of this study is to evaluate whether there are changes in DLCO during a 14-day altitude training camp (1850 m) in elite swimmers and the acute effects of a combined training session of swimming in moderate hypoxia and 44-min cycling in acute normobaric severe hypoxia (3000 m). Participants were eight international level swimmers (5 females and 3 males; 17-24 years old; 173.5 ± 5.5 cm; 64.4 ± 5.3 kg) with a training volume of 80 km per week. The single-breath method was used to measure the changes in DLCO and functional gas exchange parameters. No changes in DLCO after a 14-day altitude training camp at 1850 m were detected but a decrease in alveolar volume (VA; 7.13 ± 1.61 vs. 6.50 ± 1.59 L; p = 0.005; d = 0.396) and an increase in the transfer coefficient of the lung for carbon monoxide (KCO; 6.23 ± 1.03 vs. 6.83 ± 1.31 mL·min-1·mmHg-1·L-1; p = 0.038; d = 0.509) after the altitude camp were observed. During the acute hypoxia combined session, there were no changes in DLCO after swimming training at 1850 m, but there was a decrease in DLCO after cycling at a simulated altitude of 3000 m (40.6 ± 10.8 vs. 36.8 ± 11.2 mL·min-1·mmHg-1; p = 0.044; d = 0.341). A training camp at moderate altitude did not alter pulmonary diffusing capacity in elite swimmers, although a cycling session at a higher simulated altitude caused a certain degree of impairment of the alveolar-capillary gas exchange.


Assuntos
Altitude , Natação , Adolescente , Feminino , Humanos , Pulmão , Masculino , Capacidade de Difusão Pulmonar , Troca Gasosa Pulmonar , Natação/fisiologia , Adulto Jovem
14.
Rev. esp. patol. torac ; 32(2): 100-105, mayo 2020. tab
Artigo em Espanhol | IBECS | ID: ibc-193902

RESUMO

OBJETIVO: Es controvertido el efecto que la natación en piscinas cubiertas puede tener sobre la función pulmonar y sobre los parámetros de inflamación bronquial. El objetivo del estudio fue estudiar la evolución de parámetros funcionales y de inflamación antes y después del baño en usuarios de piscinas cubiertas y sin patología respiratoria conocida. METODOLOGÍA: Estudio observacional prospectivo en el que se incluyeron nadadores habituales de piscinas cubiertas. Los individuos incluidos en el estudio no presentaban antecedentes de asma ni alteraciones funcionales o de inflamación bronquial en el momento de la inclusión. Se realizaron pruebas funcionales (espirometría) y medida de inflamación (FeNO) minutos antes y tras el baño en diferentes piscinas públicas. Se analizaron de forma paralela los parámetros físico-químicos del agua de dichas piscinas en el momento de la natación y que fueron proporcionados por la Inspección de Sanidad adscrita a dicha piscina pública. RESULTADOS: Fueron incluidos 50 nadadores, 26 hombres y 24 mujeres, de edad media 40,8 ± 10,8 años. El tiempo de inmersión fue de 32 minutos. Encontramos diferencias antes y tras la inmersión. En los nadadores incluidos mejoraron tras la inmersión de forma significativa la FVC (p < 0,05), y el FEV1 (p < 0,04) así como disminuyó el FENO (p < 0,01) Las características del agua de las piscinas, medidas según los protocolos habituales de sanidad, se encontraron en todos los casos dentro del rango habitual determinados en el Real Decreto 742/2013, de 27 de septiembre (BOE, Viernes 11 de octubre de 2013), por el que se establecen los criterios técnico-sanitarios de las piscinas. Tras el análisis estadístico, no se obtuvieron diferencias en parámetros de función e inflamación bronquial en relación con los datos físicos y químicos del agua de las piscinas y recogidos en el momento de la inclusión de los pacientes en el estudio. CONCLUSIONES: Hemos objetivado una mejoría significativa de los parámetros funcionales respiratorios en nadadores de piscinas cubiertas


INTRODUCTION: it is controversial the effect that swimming in indoor swimming pool can have on lung function and parameters of inflammation. The objective of the study was to study the evolution of functional parameters and inflammation before and after swimming in users of indoor swimming pools and without known respiratory pathology. MATERIAL AND METHODS: this was an observational prospective study in which regular swimmers were included. Individuals included in the study had no history of asthma or functional or inflammatory diseases at the time of inclusion. Functional tests (spirometry) and inflammation measurement (FENO) were performed minutes before and after bathing in different public swimming pools. The physical-chemical parameters of the water of these swimming pools were analyzed in parallel at the time of swimming and were provided by the sanitary inspection attached to said public swimming pool. RESULTS: were included 50 swimmers, 26 men and 24 women, mean age 40.8 ± 10.8 years. The immersion time was 32 minutes. In the swimmers included, FVC significantly improved after dipping (p < 0.05), FEV1 (p < 0.04) as did FENO (p < 0.01). The water characteristics of the swimming pools, measured according to the usual health protocols, were found in all cases within the usual range determined in Royal Decree 742/2013, de 27th September (BOE 11th October 2013). After statistical analysis, no differences were found in parameters of bronchial function and inflammation in relation to the physical and chemical data of the swimming pools included in the study. CONCLUSIONS: we have observed a significant improvement in respiratory functional parameters in indoor swimming pool swimmer


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Pulmão/fisiologia , Piscinas , Inflamação/fisiopatologia , Testes de Função Respiratória , Natação/fisiologia , Estudos Prospectivos , Espirometria , Microbiologia da Água
15.
PLoS One ; 15(4): e0231522, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32298322

RESUMO

PURPOSE: The Polar OH1 is an optical heart rate (HR) sensor which can be used on different parts of the body. The purpose of the study was to evaluate the validity of the OH1 as well as a wrist worn heart rate device (Polar M600) during swimming. METHODS: Twenty-six well-trained competitive swimmers performed a regular training session including different swimming intensities. During the training the swimmers wore a H10 HR sensor with Polar Pro strap (H10) underneath the swim suit, a Polar OH1 optical HR sensor (OH1) underneath the swimming cap at the temple, and a sports watch with optical HR sensor, Polar M600 smart watch (M600) on the wrist. RESULTS: No difference in HRmax, HRmean and HRmin between H10 and OH1 were evident. The HRmax and HRmean obtained by the M600 was significantly lower than the obtained by H10 and OH1 (p < 0.05). The ICC showed mostly excellent agreements between H10 and OH1 and poor to good agreements between H10 and M600. Bland-Altmann plot for M600 vs. H10 indicates upper and lower limits of agreement of -53.0 to 33.9 beats per minute. For OH1 vs. H10 the upper and lower limits of agreement were -26.9 to 24.7 beats per minute. CONCLUSION: The Polar OH1 optical HR sensor is a valid tool to monitor HR of different intensities during swimming whereas the Polar M600 smart watch as a wrist worn device is less accurate.


Assuntos
Frequência Cardíaca/fisiologia , Monitorização Ambulatorial/métodos , Natação/fisiologia , Adolescente , Feminino , Humanos , Masculino , Monitorização Ambulatorial/instrumentação , Dispositivos Ópticos , Reprodutibilidade dos Testes , Natação/educação , Dispositivos Eletrônicos Vestíveis , Punho
16.
J Sports Med Phys Fitness ; 60(7): 957-964, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32253897

RESUMO

BACKGROUND: Swimming relay events have the concern regarding a good start is shared between the incoming and outgoing swimmers. The aim of this study was to evaluate changes in exchange block time (EBT) for swimming relay events as a result of a four-week training program using the occlusion technique. METHODS: Twenty-eight national swimmers, 12 males (age: 17±1.83 years) and 16 females (age: 19.94±5.65 years) participated in this study. Subjects were required to undergo a training program on visual perception in relay swimming over the course of four weeks; they watched videos corresponding to the last movements of a swimmer during a 4×100m freestyle relay event. The videos were presented with temporal occlusion corresponding to predetermined approaching distances (7.5 m, 5.0 m, and 2.5 m). Swimmers were required to simulate a typical position for exiting the block and to estimate the time-to-contact of the incoming swimmer. The EBT was collected during a real 4×100-m freestyle competition before and after the application of the training program. RESULTS: Female swimmers showed a decreased in EBT, with an improvement of 1.42%, despite there not being a significant difference (P=0.68). The male swimmers had a higher improvement in EBT after the training, with a decrease of 13.34% (P=0.68). CONCLUSIONS: Visual perception practice using video occlusion techniques seems to have a positive effect. On EBT in swimming relay events, particularly in female swimmers.


Assuntos
Desempenho Atlético/fisiologia , Desempenho Atlético/psicologia , Comportamento Competitivo/fisiologia , Condicionamento Físico Humano/métodos , Natação/fisiologia , Natação/psicologia , Percepção Visual/fisiologia , Adolescente , Feminino , Humanos , Masculino , Fatores Sexuais , Software , Fatores de Tempo , Adulto Jovem
17.
J Sports Sci ; 38(14): 1666-1673, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32321367

RESUMO

Two studies were employed to test the reliability and validity of the Swimming Competence Questionnaire (SCQ) among primary school children. Study 1 was a cross-sectional survey in 4959 primary school children. Study 2 was a pre-post-test quasi-experiment among 1609 primary school children who underwent a 20-lesson learn-to-swim programme. In Study 1, exploratory structural equation modelling revealed excellent goodness-of-fit and scale reliability for a two-factor model comprising distance and skill factors, which supported the construct and convergent validity. SCQ scores were significantly and positively correlated with swimming outcomes (i.e., self-efficacy, intention, swimming frequency), which supported SCQ's concurrent and criterion validity. Average variance extracted for the SCQ factors exceeded cut-off criteria supporting discriminant validity. In Study 2, pre-test SCQ scores correlated significantly and positively with the SCQ scores, self-efficacy, intention, and swimming frequency at post-test, which supported SCQ's test-retest reliability and predictive validity. Positive intraclass correlation between SCQ scores and coach ratings at post-test provided evidence for SCQ's inter-rater reliability. SCQ scores significantly improved at post-test, which supported SCQ's ecological validity. In conclusion, findings indicate that the SCQ is a valid and reliable measure to assess primary school children's swimming competence, in terms of swimming distance and basic water survival skills.


Assuntos
Desempenho Atlético/fisiologia , Destreza Motora/fisiologia , Inquéritos e Questionários , Natação/fisiologia , Adolescente , Criança , Pré-Escolar , Estudos Transversais , Hong Kong , Humanos , Reprodutibilidade dos Testes , Autorrelato
18.
J Neuroeng Rehabil ; 17(1): 51, 2020 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-32299483

RESUMO

BACKGROUND: Participation in physical and therapeutic activities is usually severely restricted after a spinal cord injury (SCI). Reasons for this are the associated loss of voluntary motor function, inefficient temperature regulation of the affected extremities, and early muscle fatigue. Hydrotherapy or swim training offer an inherent weight relief, reduce spasticity and improve coordination, muscle strength and fitness. METHODS: We present a new hybrid exercise modality that combines functional electrical stimulation (FES) of the knee extensors and transcutaneous spinal cord stimulation (tSCS) with paraplegic front crawl swimming. tSCS is used to stimulate the afferent fibers of the L2-S2 posterior roots for spasticity reduction. By activating the tSCS, the trunk musculature is recruited at a motor level. This shall improve trunk stability and straighten the upper body. Within this feasibility study, two complete SCI subjects (both ASIA scale A, lesion level Th5/6), who have been proficient front crawl swimmers, conducted a 10-week swim training with stimulation support. In an additional assessment swim session nine months after the training, the knee extension, hip extension, and trunk roll angles where measured using waterproof inertial measurement units (IMUs) and compared for different swimming conditions (no stimulation, tSCS, FES, FES plus tSCS). RESULTS: For both subjects, a training effect over the 10-week swim training was observed in terms of measured lap times (16 m pool) for all swimming conditions. Swimming supported by FES reduced lap times by 15.4% and 8.7% on average for Subject A and Subject B, respectively. Adding tSCS support yielded even greater mean decreases of 19.3% and 20.9% for Subjects A and B, respectively. Additionally, both subjects individually reported that swimming with tSCS for 30-45 minutes eliminated spasticity in the lower extremities for up to 4 hours beyond the duration of the session. Comparing the median as well as the interquartile range of all different settings, the IMU-based motion analysis revealed that FES as well as FES+tSCS improve knee extension in both subjects, while hip extension was only increased in one subject. Trunk roll angles were similar for all swimming conditions. tSCS had no influence on the knee and hip joint angles. Both subjects reported that stimulation-assisted swimming is comfortable, enjoyable, and they would like to use such a device for recreational training and rehabilitation in the future. CONCLUSIONS: Stimulation-assisted swimming seems to be a promising new form of hybrid exercise for SCI people. It is safe to use with reusable silicone electrodes and can be performed independently by experienced paraplegic swimmers except for transfer to water. The study results indicate that swimming speed can be increased by the proposed methods and spasticity can be reduced by prolonged swim sessions with tSCS and FES. The combination of stimulation with hydrotherapy might be a promising therapy for neurologic rehabilitation in incomplete SCI, stroke or multiples sclerosis patients. Therefore, further studies shall incorporate other neurologic disorders and investigate the potential benefits of FES and tSCS therapy in the water for gait and balance.


Assuntos
Terapia por Estimulação Elétrica/métodos , Terapia por Exercício/métodos , Paraplegia/reabilitação , Traumatismos da Medula Espinal/reabilitação , Natação/fisiologia , Adulto , Terapia por Estimulação Elétrica/instrumentação , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Espasticidade Muscular/etiologia , Espasticidade Muscular/reabilitação , Paraplegia/etiologia , Projetos Piloto , Traumatismos da Medula Espinal/complicações
19.
Proc Natl Acad Sci U S A ; 117(19): 10585-10592, 2020 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-32341168

RESUMO

The anterior body of many fishes is shaped like an airfoil turned on its side. With an oscillating angle to the swimming direction, such an airfoil experiences negative pressure due to both its shape and pitching movements. This negative pressure acts as thrust forces on the anterior body. Here, we apply a high-resolution, pressure-based approach to describe how two fishes, bluegill sunfish (Lepomis macrochirus Rafinesque) and brook trout (Salvelinus fontinalis Mitchill), swimming in the carangiform mode, the most common fish swimming mode, generate thrust on their anterior bodies using leading-edge suction mechanics, much like an airfoil. These mechanics contrast with those previously reported in lampreys-anguilliform swimmers-which produce thrust with negative pressure but do so through undulatory mechanics. The thrust produced on the anterior bodies of these carangiform swimmers through negative pressure comprises 28% of the total thrust produced over the body and caudal fin, substantially decreasing the net drag on the anterior body. On the posterior region, subtle differences in body shape and kinematics allow trout to produce more thrust than bluegill, suggesting that they may swim more effectively. Despite the large phylogenetic distance between these species, and differences near the tail, the pressure profiles around the anterior body are similar. We suggest that such airfoil-like mechanics are highly efficient, because they require very little movement and therefore relatively little active muscular energy, and may be used by a wide range of fishes since many species have appropriately shaped bodies.


Assuntos
Fenômenos Biomecânicos/fisiologia , Peixes/fisiologia , Natação/fisiologia , Animais , Peixes/anatomia & histologia , Movimento , Perciformes/fisiologia , Fenômenos Físicos , Truta/fisiologia
20.
Arch Osteoporos ; 15(1): 64, 2020 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-32335776

RESUMO

This study investigated the impact and non-impact sports on bone mineral density accrual in adolescents over 18 months. The impact sports were beneficial for bone health (accrual of bone density). In contrast, swimmers had similar or lower bone mineral density compared with the control group depending on the skeletal site. PURPOSE: To investigate the impact and non-impact sports on bone mineral density (BMD) accrual in adolescents over a period of 18 months METHODS: The sample was composed of 71 adolescents, avarage age of 12.7 (± 1.7) years old at baseline. Bone outcomes were compared according to the loading of the sports practiced (impact sports, n = 33 [basketball, karate, and judo], non-impact sport, n = 18 [swimming], and control group, n = 20). Areal bone mineral density (aBMD) was measured by dual-energy X-ray absorptiometry (DXA) and bone mineral apparent density (BMAD) estimated through equation. The results were compared between the groups using analysis of variance and analysis of covariance. RESULTS: Adjusted aBMD at lower limbs, whole body less head (WBLH), and adjusted WBLH BMAD were significantly greater in the impact sport group than the non-impact sport group at all time points. Adjusted upper limbs aBMD was significantly higher at the impact sports group compared to the non-impact sport group at 9 months and 18 months, besides compared to the control group at baseline and 18 months. Non-impact sport group presented a significant lower adjusted aBMD compared with control group at lower limbs and WBLH at 9 months, and at 9 months and 18 months in WBLH BMAD. There was a significant interaction (time × sport group) at upper limbs (p = 0.042) and WBLH aBMD (p = 0.006), and WBLH BMAD (p < 0.001). CONCLUSION: Impact sports were more beneficial on accumulating aBMD and BMAD over a period of 18 months, while non-impact group (swimmers) had similar and lower aBMD and BMAD compared with the control group.


Assuntos
Desenvolvimento do Adolescente/fisiologia , Basquetebol/fisiologia , Desenvolvimento Ósseo/fisiologia , Artes Marciais/fisiologia , Natação/fisiologia , Absorciometria de Fóton/métodos , Adolescente , Análise de Variância , Densidade Óssea , Criança , Feminino , Humanos , Extremidade Inferior/diagnóstico por imagem , Masculino , Fatores de Tempo , Extremidade Superior/diagnóstico por imagem
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