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1.
PLoS One ; 17(10): e0275332, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36194592

RESUMO

PURPOSE: Effects of intense and/or prolonged exercise have been studied extensively in male athletes. Nevertheless, data are scare on the effect of long duration events on cardiac function in female athletes. Our aim was to investigate the effect of a long-lasting moderate-intensity stage cycling event on cardiac function of young female athletes. METHODS: Seven well-trained female cyclists were included. They completed a cycling event of 3529 km on 23 days. All underwent an echocardiography on 6 time-points (baseline and at the arrival of day (D) 3, 7, 12, 13 and 23). Cardiac function was assessed by conventional echocardiography, tissue Doppler imaging and speckle tracking techniques. Daily exercise load was determined by heart rate (HR), power output and rate of perceived exertion data (RPE, Borg scale). RESULTS: All stages were mainly done at moderate intensity (average HR: 65% of maximal, average aerobic power output: 36% of maximal, average RPE: 4). Resting HR measured at the time of echocardiography did not vary during the event. Resting cardiac dimensions did not significantly change during the 23 days of cycling. No significant modification of cardiac function, whatever the studied cavity, were observed all along the event. CONCLUSION: The results suggest that, in the context of our case study, the long-lasting moderate-intensity stage cycling event was not associated with cardiac function alteration. Nevertheless, we must be careful in interpreting them due to the limits of an underpowered study.


Assuntos
Ciclismo , Esforço Físico , Atletas , Ciclismo/fisiologia , Teste de Esforço , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Esforço Físico/fisiologia
2.
Front Neurosci ; 14: 576308, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33343278

RESUMO

BACKGROUND: Heart rate (HR) and HR variability (HRV) indices are established tools to detect abnormal recovery status in athletes. A low HR and vagally mediated HRV index change between supine and standing positions reflected a maladaptive training stress-recovery status. OBJECTIVES: Our study was focused on a female multistage cycling event. Its overall aim was twofold: (1) quantify the correlation between (a) the change in HR and HRV indices during an active orthostatic test and (b) subjective/objective fatigue, physical load, and training level indicators; and (2) formulate a model predicting the stress-recovery status as indexed by Δ â¢ R ⁢ R ¯ and ΔLnRMSSD (defined as the difference between standing and supine mean RR intervals and LnRMSSD, respectively), based on subjective/objective fatigue indicators, physical load, and training levels. METHODS: Ten female cyclists traveled the route of the 2017 Tour de France, comprising 21 stages of 200 km on average. From 4 days before the beginning of the event itself, and until 1 day after its completion, every morning, each cyclist was subjected to HR and HRV measurements, first at rest in a supine position and then in a standing position. The correlation between HR and HRV indices and subjective/objective fatigue, physical load, and training level indicators was then computed. Finally, several multivariable linear models were tested to analyze the relationships between HR and HRV indices, fatigue, workload, and training level indicators. RESULTS: HR changes appeared as a reliable indicator of stress-recovery status. Fatigue, training level, and Δ â¢ R ⁢ R ¯ displayed a linear relationship. Among a large number of linear models tested, the best one to predict stress-recovery status was the following: Δ â¢ R ⁢ R ¯ = 1,249.37+12.32V̇O2 max + 0.36 km⋅week-1-8.83 HR max -5.8 RPE-28.41 perceived fatigue with an adjusted R 2 = 0.322. CONCLUSION: The proposed model can help to directly assess the adaptation status of an athlete from RR measurements and thus to anticipate a decrease in performance due to fatigue, particularly during a multistage endurance event.

3.
PLoS One ; 14(3): e0213472, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30845249

RESUMO

OBJECTIVES: This study aimed to analyze the daily heart rate variability (HRV) in well-trained female cyclists during the 2017 Tour de France circuit and to relate it to the load and perceived exertion response. METHODS: Ten female cyclists volunteered to participate in the study. HRV was recorded with a portable heart rate monitor each morning at rest in supine (7 min.) and upright (7 min.) positions, as well as throughout each day's stage. Pre-Tour baseline HRV recordings were made, as well as during the four weeks following completion of the Tour. Exercise daily load was assessed using the training impulse score (TRIMPS). Post-exercise rate of perceived exertion (RPE) was assessed daily using the Borg CR-10 scale. RESULTS: The results show a HRV imbalance, increase of sympathetic and decrease of vagal activities respectively, along the event that correlated with rate of perceived exertion (r = 0.46), training impulse score (r = 0.60), and kilometers (r = 046). The greatest change in HRV balance was observed the days after the greatest relative physical load. Mean heart rate and heart rate variability values returned to their baseline values one week after completion of the event. CONCLUSIONS: Despite incomplete recovery from day-to-day, fatigue is not summative or augmented with each successive stage and its physical load. Just one week is sufficient to restore baseline values. Heart rate and HRV can be used as a tool to strategically plan the effort of female cyclists that participate in multi-stage events.


Assuntos
Ciclismo/fisiologia , Frequência Cardíaca/fisiologia , Esforço Físico/fisiologia , Adulto , Atletas , Fadiga , Feminino , França , Humanos
4.
Eur J Sport Sci ; 15(2): 85-93, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-24942164

RESUMO

Prior reports have described the limitations of quantifying internal training loads using hear rate (HR)-based objective methods such as the training impulse (TRIMP) method, especially when high-intensity interval exercises are performed. A weakness of the TRIMP method is that it does not discriminate between exercise and rest periods, expressing both states into a single mean intensity value that could lead to an underestimate of training loads. This study was designed to compare Banister's original TRIMP method (1991) and a modified calculation procedure (TRIMPc) based on the cumulative sum of partial TRIMP, and to determine how each model relates to the session rating of perceived exertion (s-RPE), a HR-independent training load indicator. Over four weeks, 17 elite swimmers completed 328 pool training sessions. Mean HR for the full duration of a session and partial values for each 50 m of swimming distance and rest period were recorded to calculate the classic TRIMP and the proposed variant (TRIMPc). The s-RPE questionnaire was self-administered 30 minutes after each training session. Both TRIMPc and TRIMP measures strongly correlated with s-RPE scores (r = 0.724 and 0.702, respectively; P < 0.001). However, TRIMPc was ∼ 9% higher on average than TRIMP (117 ± 53 vs. 107 ± 47; P < 0.001), with proportionally greater inter-method difference with increasing workload intensity. Therefore, TRIMPc appears to be a more accurate and appropriate procedure for quantifying training load, particularly when monitoring interval training sessions, since it allows weighting both exercise and recovery intervals separately for the corresponding HR-derived intensity.


Assuntos
Frequência Cardíaca , Educação Física e Treinamento , Esforço Físico/fisiologia , Natação/fisiologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Consumo de Oxigênio , Percepção , Descanso/fisiologia , Inquéritos e Questionários , Adulto Jovem
5.
Rev. psicol. deport ; 23(1): 173-180, ene.-jun. 2014. tab, ilus
Artigo em Espanhol | IBECS | ID: ibc-118656

RESUMO

El objetivo de este estudio fue caracterizar la estructura de las rutinas de solo y dúo de natación sincronizada. Para ello se utilizó un diseño observacional puntual, nomotético y multidimensional. El instrumento observacional ad hoc fue validado por 12 especialistas. Se utilizó como instrumento de registro el programa LINCE. La fiabilidad en la observación se determinó mediante el grado de concordancia intra e interobservador. Dieciocho nadadoras (seis medallistas olímpicas) participaron en el estudio. Se analizaron 39 rutinas: solo técnico (n = 9), solo libre (n = 11), dúo técnico (n = 10) y dúo libre (n = 9). El 61.6 ± 6.4 %) del tiempo de competición las nadadoras estaban con la cara dentro del agua, con apneas máximas de 21.1 ± 4.0 s. La posición más utilizada en el conjunto de rutinas fue la inferior (43.2 ± 5.3 %), siendo la fase de inmersión alta inferior la más reproducida (35.3 ± 5.0 %). En conclusión: 1) se dispone de una herramienta válida para el análisis de la estructura de las rutinas en natación sincronizada, 2) existen diferencias significativas en la estructura de las rutinas atendiendo a la duración total, las fases relativas de apnea y a la inmersión en distintas posiciones corporales


The aim of this study was to characterize the structure of solo and duet-based synchronized swimming routines. This was done using a specific nomothetic multidimensional observational design. The ad hoc observational instrument was validated by 12 specialists. The data was recorded using LINCE software, and observational reliability was determined by calculating the degree of intra-observer and inter-observer agreement. The participants were 18 female swimmers (including six Olympic medallists), and 39 routines were analysed: technical solos (n = 9), free solos (n = 11), technical duets (n = 10) and free duets (n = 9). The swimmers spent 61.6 ± 6.4 % of the competition time with their faces immersed in the water, with maximum apnea of 21.1 ± 4.0 s. The inverted-vertical position was the most widely taken in routines (43.2 ± 5.3 %), with the phase of deep immersion in that position being the most commonly reproduced (35.3 ± 5.0 %). In conclusion: 1) the observational instrument is a valid tool for analysing the structure of routines in synchronized swimming; and 2) there are significant differences in the structure of routines as regards their total duration, episodes of apnea, and the degree of immersion in different body positions


Natação sincronizada, Metodologia observacional, Apneia, Posição corporal, Imersão. RESUMO: O objectivo deste estudo foi caracterizar a estrutura das rotinas individuais e duplas de natação sincronizada. Para tal foi utilizado um delineamento observacional pontual, nomotético e multidimensional. O instrumento observacional ad hoc foi validado por 12 especialistas. Utilizou-se como instrumento de registo o programa LINCE. A fidelidade na observação foi determinada mediante o grau de concordância intra e interobservador. Dezoito nadadoras (seis medalhistas olímpicas) participaram no estudo. Foram analisadas 39 rotinas; solo técnico (n = 9), solo livre (n = 11), duo técnico (n = 10) e duo livre (n = 9). As nadadoras estavam totalmente imersas na água em 61.6 % (± 6.4 %) do tempo de competição, com apneias máximas de 21.1 ± 4.0 s. A posição mais utilizada no conjunto de rotinas foi a imersão inferior (43.2 ± 5.3 %), sendo a fase de imersão total a mais reproduzida (35.3 ± 5.0 %). Em suma: 1) dispõem-se de uma ferramenta válida para a análise da estructura das rotinas na natação sincronizada, 2) existem diferenças significativas na estructura das rotinas atendendo à duração total, às fases relativas de apneia e à imersão em distintas posições corporais


Assuntos
Humanos , Masculino , Feminino , Natação/psicologia , Natação/estatística & dados numéricos , Natação/normas , Apneia/epidemiologia , Apneia/prevenção & controle , Apneia/psicologia , Síndromes da Apneia do Sono/psicologia , Estudos Observacionais como Assunto , Natação/classificação , Natação/educação , Natação/tendências , Imersão/fisiopatologia
6.
J Strength Cond Res ; 28(3): 742-51, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23820563

RESUMO

The aim of the study is to compare the heart rate (HR) and rate of perceived exertion (RPE) responses as internal load indicators while performing duet routines during training and competition, both in the technical and free programs of synchronized swimming (SS). Participants were 10 SS Olympic medalists (age, 17.4 ± 3.0 years; height, 164.0 ± 6.1 cm; body mass, 52.0 ± 6.4 kg; training, 36.3 ± 6.2 h·wk; experience, 9.2 ± 2.6 years). They were monitored while performing the same technical duet or free duet, during a training session (T) and during an official competition (C). Heart rate was continuously monitored. Rate of perceived exertion was assessed using the Borg CR10 scale. Heart rate responses during T and C were almost identical: pre-exercise mean HR (b·min) was 130.5 ± 13.9 (T) and 133.6 ± 7.7 (C) and quickly increased yielding mean peak values of 184.8 ± 5.8 (T) and 184.8 ± 6.6 (C), with interspersed bradycardic events down to 86.6 ± 4 (T) and 86.3 ± 5 (C). Routines were perceived as "hard" to "extremely hard" by the swimmers in both conditions, and mean RPE scores (0-10+) were equally high during C (7.9 ± 1.2) and T (7.5 ± 1.2) (p = 0.223). Rate of perceived exertion inversely correlated with minimum (R = -0.545; p = 0.008) and mean HR (R = -0.452; p = 0.026) and positively correlated with HRrange (R = 0.520; p = 0.011). The internal load imposed by SS duets performed during training is virtually identical to that elicited in a real competitive situation. Therefore, practicing competitive routines is suitable for developing and maintaining the cardiovascular fitness that is needed for specific conditioning in elite synchronized swimmers, with the added value of favoring exercise automaticity, interindividual coordination, and artistic expression simultaneously.


Assuntos
Comportamento Competitivo/fisiologia , Frequência Cardíaca , Esforço Físico/fisiologia , Prática Psicológica , Natação/fisiologia , Adolescente , Humanos , Monitorização Fisiológica , Condicionamento Físico Humano/métodos , Condicionamento Físico Humano/fisiologia , Aptidão Física/fisiologia , Adulto Jovem
7.
Nutrients ; 7(1): 209-22, 2014 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-25558906

RESUMO

UNLABELLED: The nutritional strategy during an ultra-endurance triathlon (UET) is one of the main concerns of athletes competing in such events. The purpose of this study is to provide a proper characterization of the energy and fluid intake during real competition in male triathletes during a complete UET and to estimate the energy expenditure (EE) and the fluid balance through the race. METHODS: Eleven triathletes performed a UET. All food and drinks ingested during the race were weighed and recorded in order to assess the energy intake (EI) during the race. The EE was estimated from heart rate (HR) recordings during the race, using the individual HR-oxygen uptake (Vo2) regressions developed from three incremental tests on the 50-m swimming pool, cycle ergometer, and running treadmill. Additionally, body mass (BM), total body water (TBW) and intracellular (ICW) and extracellular water (ECW) were assessed before and after the race using a multifrequency bioimpedance device (BIA). RESULTS: Mean competition time and HR was 755 ± 69 min and 137 ± 6 beats/min, respectively. Mean EI was 3643 ± 1219 kcal and the estimated EE was 11,009 ± 664 kcal. Consequently, athletes showed an energy deficit of 7365 ± 1286 kcal (66.9% ± 11.7%). BM decreased significantly after the race and significant losses of TBW were found. Such losses were more related to a reduction of extracellular fluids than intracellular fluids. CONCLUSIONS: Our results confirm the high energy demands of UET races, which are not compensated by nutrient and fluid intake, resulting in a large energy deficit.


Assuntos
Atletas , Metabolismo Energético , Resistência Física , Adulto , Ciclismo , Composição Corporal , Índice de Massa Corporal , Ingestão de Líquidos , Impedância Elétrica , Ingestão de Energia , Teste de Esforço , Frequência Cardíaca , Humanos , Modelos Lineares , Masculino , Consumo de Oxigênio/fisiologia , Corrida , Sódio na Dieta/administração & dosagem , Inquéritos e Questionários , Natação , Equilíbrio Hidroeletrolítico
8.
PLoS One ; 7(11): e49098, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23155452

RESUMO

PURPOSE: We aimed to characterize the cardiovascular, lactate and perceived exertion responses in relation to performance during competition in junior and senior elite synchronized swimmers. METHODS: 34 high level senior (21.4 ± 3.6 years) and junior (15.9 ± 1.0) synchronized swimmers were monitored while performing a total of 96 routines during an official national championship in the technical and free solo, duet and team competitive programs. Heart rate was continuously monitored. Peak blood lactate was obtained from serial capillary samples during recovery. Post-exercise rate of perceived exertion was assessed using the Borg CR-10 scale. Total competition scores were obtained from official records. RESULTS: Data collection was complete in 54 cases. Pre-exercise mean heart rate (beats·min(-1)) was 129.1 ± 13.1, and quickly increased during the exercise to attain mean peak values of 191.7 ± 8.7, with interspersed bradycardic events down to 88.8 ± 28.5. Mean peak blood lactate (mmol·L(-1)) was highest in the free solo (8.5 ± 1.8) and free duet (7.6 ± 1.8) and lowest at the free team (6.2 ± 1.9). Mean RPE (0-10+) was higher in juniors (7.8 ± 0.9) than in seniors (7.1 ± 1.4). Multivariate analysis revealed that heart rate before and minimum heart rate during the routine predicted 26% of variability in final total score. CONCLUSIONS: Cardiovascular responses during competition are characterized by intense anticipatory pre-activation and rapidly developing tachycardia up to maximal levels with interspersed periods of marked bradycardia during the exercise bouts performed in apnea. Moderate blood lactate accumulation suggests an adaptive metabolic response as a result of the specific training adaptations attributed to influence of the diving response in synchronized swimmers. Competitive routines are perceived as very to extremely intense, particularly in the free solo and duets. The magnitude of anticipatory heart rate activation and bradycardic response appear to be related to performance variability.


Assuntos
Frequência Cardíaca/fisiologia , Esforço Físico/fisiologia , Natação/fisiologia , Adolescente , Atletas , Feminino , Humanos , Ácido Láctico/sangue , Consumo de Oxigênio/fisiologia
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