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1.
Br J Sports Med ; 2022 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-35680397

RESUMO

Exercise training is highly recommended in current guidelines on primary and secondary prevention of cardiovascular disease (CVD). This is based on the cardiovascular benefits of physical activity and structured exercise, ranging from improving the quality of life to reducing CVD and overall mortality. Therefore, exercise should be treated as a powerful medicine and critical component of the management plan for patients at risk for or diagnosed with CVD. A tailored approach based on the patient's personal and clinical characteristics represents a cornerstone for the benefits of exercise prescription. In this regard, the use of cardiopulmonary exercise testing is well-established for risk stratification, quantification of cardiorespiratory fitness and ventilatory thresholds for a tailored, personalised exercise prescription. The aim of this paper is to provide a practical guidance to clinicians on how to use data from cardiopulmonary exercise testing towards personalised exercise prescriptions for patients at risk of or with CVD.

2.
Br J Sports Med ; 56(5): 264-270, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34844952

RESUMO

BACKGROUND: SARS-CoV-2 infection might be associated with cardiac complications in low-risk populations, such as in competitive athletes. However, data obtained in adults cannot be directly transferred to preadolescents and adolescents who are less susceptible to adverse clinical outcomes and are often asymptomatic. OBJECTIVES: We conducted this prospective multicentre study to describe the incidence of cardiovascular complications following SARS-CoV-2 infection in a large cohort of junior athletes and to examine the effectiveness of a screening protocol for a safe return to play. METHODS: Junior competitive athletes suffering from asymptomatic or mildly symptomatic SARS-CoV-2 infection underwent cardiac screening, including physical examination, 12-lead resting ECG, echocardiogram and exercise ECG testing. Further investigations were performed in cases of abnormal findings. RESULTS: A total of 571 competitive junior athletes (14.3±2.5 years) were evaluated. About half of the population (50.3%) was mildly symptomatic during SARS-CoV-2 infection, and the average duration of symptoms was 4±1 days. Pericardial involvement was found in 3.2% of junior athletes: small pericardial effusion (2.6%), moderate pericardial effusion (0.2%) and pericarditis (0.4%). No relevant arrhythmias or myocardial inflammation was found in subjects with pericardial involvement. Athletes with pericarditis or moderate pericardial effusion were temporarily disqualified, and a gradual return to play was achieved after complete clinical resolution. CONCLUSIONS: The prevalence of cardiac involvement was low in junior athletes after asymptomatic or mild SARS-CoV-2 infection. A screening strategy primarily driven by cardiac symptoms should detect cardiac involvement from SARS-CoV-2 infection in most junior athletes. Systematic echocardiographic screening is not recommended in junior athletes.


Assuntos
COVID-19 , Cardiopatias , Adolescente , Adulto , Atletas , Humanos , Estudos Prospectivos , Volta ao Esporte , SARS-CoV-2
3.
Scand J Med Sci Sports ; 31(9): 1796-1808, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34170582

RESUMO

BACKGROUND: Although structured exercise training is strongly recommended in cardiac patients, uncertainties exist about the methods for determining exercise intensity (EI) and their correspondence with effective EI obtained by ventilatory thresholds. We aimed to determine the first (VT1 ) and second ventilatory thresholds (VT2 ) in cardiac patients, sedentary subjects, and athletes comparing VT1 and VT2 with EI defined by recommendations. METHODS: We prospectively enrolled 350 subjects (mean age: 50.7±12.9 years; 167 cardiac patients, 150 healthy sedentary subjects, and 33 competitive endurance athletes). Each subject underwent ECG, echocardiography, and cardiopulmonary exercise testing. The percentages of peak VO2 , peak heart rate (HR), and HR reserve were obtained at VT1 and VT2 and compared with the EI definition proposed by the recommendations. RESULTS: VO2 at VT1 corresponded to high rather than moderate EI in 67.1% and 79.6% of cardiac patients, applying the definition of moderate exercise by the previous recommendations and the 2020 guidelines, respectively. Most cardiac patients had VO2  values at VT2 corresponding to very-high rather than high EI (59.9% and 50.3%, by previous recommendations and 2020 guidelines, respectively). A better correspondence between ventilatory thresholds and recommended EI domains was observed in healthy subjects and athletes (90% and 93.9%, respectively). CONCLUSIONS: EI definition based on percentages of peak HR and peak VO2  may misclassify the effective EI, and the discrepancy between the individually determined and the recommended EI is particularly relevant in cardiac patients. A ventilatory threshold-based rather than a range-based approach is advisable to define an appropriate level of EI.


Assuntos
Atletas , Exercício Físico/fisiologia , Cardiopatias/fisiopatologia , Ventilação Pulmonar/fisiologia , Comportamento Sedentário , Adulto , Ecocardiografia , Teste de Esforço/métodos , Feminino , Cardiopatias/classificação , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio/fisiologia , Resistência Física , Estudos Prospectivos , Análise de Regressão , Função Ventricular Esquerda/fisiologia
4.
Scand J Med Sci Sports ; 30(3): 549-555, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31715047

RESUMO

BACKGROUND: Some concerns exist about possible detrimental effects on cardiac function of ultra-endurance competitions. The aim of this study was to evaluate the acute effects of an ultramarathon by comparing pre- and post-race 12-lead ECG features. METHODS: A total of 301 competitive athletes (mean age: 48 ± 9 years) running a 50-km ultramarathon were analyzed. Twelve-lead ECG was collected the day before the race and immediately at the finish line. According to the Italian law, athletes could have participated only after undergoing pre-participation screening that ruled out the presence of an underlying heart disease. RESULTS: After the race a significant increase in P-wave voltage (P < .001) and P-wave duration (P < .001) was found as compared to pre-race data with a higher percentage of athletes fulfilling the ECG criteria for right atrial enlargement (RAE; from 3% to 17%, P < .001). The presence of RAE post-race significantly correlated with age, hours of training/week, and years of training and inversely with time at the finish line and the final position in the ranking. T-wave and R-wave amplitude (P < .001) and QTc-interval duration (P < .001) significantly increased after the race. No significant differences in terms of supraventricular or ventricular arrhythmias were found. CONCLUSIONS: A sizeable proportion of athletes running a 50-km ultramarathon demonstrated post-race ECG signs of right heart overload but no arrhythmias. This finding supports the hypothesis that ultra-endurance races may induce transient right heart overload.


Assuntos
Arritmias Cardíacas/diagnóstico , Coração/fisiopatologia , Corrida/fisiologia , Adulto , Atletas , Comportamento Competitivo , Eletrocardiografia , Feminino , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Resistência Física
5.
Europace ; 21(10): 1566-1574, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31390465

RESUMO

AIMS: Twelve-lead electrocardiogram (ECG) is an established tool in the evaluation of athletes, providing information about life-threatening cardiovascular diseases, such as long QT syndrome. However, the interpretation of ECG is sometimes challenging in children, particularly for the repolarization phase. The aim of this prospective, longitudinal study was to determinate the distribution of QT interval in children practicing sport and to evaluate changes in QT duration overtime. METHODS AND RESULTS: A population of 1473 preadolescents practising sport (12.0 ± 1.8 years, 7-15 years) was analysed. Each athlete was evaluated at baseline, mid-term, and end of the study (mean follow-up: 3 ± 1 years). QT interval was corrected with Bazett (B) and Fridericia (F) formulae. At baseline QT interval corrected with the Bazett formula (QTcB) was 412 ± 25 ms and QT interval corrected with the Fridericia formula (QTcF) 387 ± 21 ms, with no changes during follow-up. Ten children (0.68%) had an abnormal QTc. In those with QTcB and QTcF ≥480 ms, QTc duration persisted abnormal during the follow-up and they were disqualified. Conversely, children with 460 ms < (QTcB) <480 ms had a normal QTc interval at the end of the study. These children had also a normal QTcF. Mean difference in the calculation of QT between the two formulae was 25 ± 11 ms (P < 0.0001). For resting heart rate (HR) ≥82 b.p.m., QTcF was independent from HR contrary to QTcB. CONCLUSION: Normal QTc interval does not change over time in preadolescents. A minority of them has a QTc ≥480 ms; in these subjects, QTc interval remains prolonged. The use of Bazett and Fridericia correction formulae is not interchangeable and the Fridericia correction should be preferred in preadolescents with a resting HR ≥82 b.p.m.


Assuntos
Algoritmos , Eletrocardiografia/métodos , Frequência Cardíaca/fisiologia , Síndrome do QT Longo/fisiopatologia , Esportes/fisiologia , Adolescente , Criança , Feminino , Seguimentos , Humanos , Masculino , Estudos Prospectivos
7.
J Sports Sci ; 36(22): 2608-2613, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29708859

RESUMO

Bioelectrical impedance vector-analysis (BIVA) describes cell-mass, cell function and hydration status of an individual or a group. The goal of the present investigation was to provide bioelectrical impedance data for 525 male road cyclists (155 professionals, 79 elite, 59 elite-youth, and 232 amateurs) at the time of their optimal performance level. Data were plotted on the resistance-reactance (R-Xc) graph to characterize cyclists group vectors using BIVA. Compared to the general male population, the mean vector position of the road cyclists indicates a higher body cell mass (BCM) and phase angle (p<0.001). The vector position of the high-performance, compared to the amateur cyclists showed similar patterns with higher BCM and phase angles and higher reactance values for the high-performance athletes (p<0.001). The bio-impedance data were used to calculate the 50%, 75%, and 95% tolerance ellipses of each group of cyclists. The characteristic vector positions of the road cyclists indicate normal hydration and greater muscle mass and function of the high-performance cyclists compared to amateur cyclists and the normal population. The cyclists specific tolerance ellipses, particularly the high-performance cyclists might be used for classifying a cyclist according to the individual vector position and to define target vector regions for lower level cyclists.


Assuntos
Desempenho Atlético/fisiologia , Ciclismo/fisiologia , Composição Corporal , Impedância Elétrica , Adolescente , Adulto , Desempenho Atlético/classificação , Ciclismo/classificação , Índice de Massa Corporal , Humanos , Masculino , Estado de Hidratação do Organismo , Condicionamento Físico Humano , Adulto Jovem
8.
Eur J Neurosci ; 43(4): 486-93, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26547276

RESUMO

Pain processing is associated with neural activity in a number of widespread brain regions. Here, we investigated whether functional connectivity at rest between these brain regions is associated with individual and sex-related differences in thermal pain and relief responsiveness. Twenty healthy volunteers (ten females) were scanned with functional magnetic resonance imaging in resting conditions. Half an hour after scanning, we administered thermal pain on the back of their right hand and collected pain and relief ratings in two separate runs of twelve stimuli each. Across the whole group, mean pain ratings were associated with decreased connectivity at rest between brain regions belonging to the default mode and the visual resting-state network. In men, pain measures correlated with increased connectivity within the visual resting-state network. In women, in contrast, decreased connectivity between this network and parietal and prefrontal brain regions implicated in affective cognitive control were associated with both pain and relief ratings. Our findings indicate that the well documented individual variability and sex differences in pain sensitivity may be explained, at least in part, by network dynamics at rest in these brain regions.


Assuntos
Mapeamento Encefálico , Encéfalo/fisiopatologia , Rede Nervosa/fisiopatologia , Dor/fisiopatologia , Descanso/fisiologia , Caracteres Sexuais , Adulto , Encéfalo/fisiologia , Mapeamento Encefálico/métodos , Feminino , Voluntários Saudáveis , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
9.
Exp Brain Res ; 234(7): 1997-2005, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26952051

RESUMO

Most of the cerebral functions are asymmetrically represented in the two hemispheres. Moreover, dexterity and coordination of the distal segment of the dominant limbs depend on cortico-motor lateralization. In this study, we investigated whether postural control may be also considered a lateralized hemispheric brain function. To this aim, 15 young subjects were tested in standing position by measuring center of pressure (COP) shifts along the anteroposterior axis (COP-Y) during dynamic posturography before and after continuous Theta Burst Stimulation (cTBS) intervention applied to the dominant or non-dominant M1 hand area as well as to the vertex. We show that when subjects were expecting a forward platform translation, the COP-Y was positioned significantly backward or forward after dominant or non-dominant M1 stimulation, respectively. We postulate that cTBS applied on M1 may have disrupted the functional connectivity between intra- and interhemispheric areas implicated in the anticipatory control of postural stability. This study suggests a functional asymmetry between the two homologous primary motor areas, with the dominant hemisphere playing a critical role in the selection of the appropriate postural control strategy.


Assuntos
Antecipação Psicológica/fisiologia , Lateralidade Funcional/fisiologia , Córtex Motor/fisiologia , Equilíbrio Postural/fisiologia , Postura/fisiologia , Estimulação Magnética Transcraniana/métodos , Adulto , Feminino , Humanos , Masculino , Ritmo Teta/fisiologia , Adulto Jovem
10.
Neurol Sci ; 36(9): 1611-5, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25896622

RESUMO

Increased mechanosensitivity of the median nerve in carpal tunnel syndrome (CTS) has been demonstrated during upper limb tension test 1 (ULTT1) when the nerve is passively elongated. However, the neurophysiological changes of the sensory axons during stressing activities are unknown. The aim of present study was to verify possible changes in the excitability of median nerve afferent axons following nerve stress in elongation, in subjects with and without CTS. Eight CTS hands and eight controls were selected. Recruitment properties of the median nerve were studied by analyzing the relationship between the intensity of electrical stimulation and the size of motor response, before and after intermittent-repetitive neural mobilization. Only in CTS hands, after the intervention, the stimulus-response curve was strikingly abnormal: both plateau and slope values were significantly lower. During anatomical stress across the median nerve in elongation, compressive forces may exert mechanical traction on the median nerve, since it is 'tethered' at the carpal tunnel, resulting inactivation of Na(+) channels at the wrist, or impairment of energy-dependent processes which affect axonal conduction block. We conclude that in entrapment neuropathies, neural mobilization during nerve elongation may generate conduction failure in peripheral nerve. Our study supports specific considerations for patient education and therapeutic approaches.


Assuntos
Síndrome do Túnel Carpal/fisiopatologia , Nervo Mediano/fisiopatologia , Postura/fisiologia , Adulto , Estimulação Elétrica , Eletromiografia , Potencial Evocado Motor/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estresse Fisiológico/fisiologia
11.
Eur J Appl Physiol ; 115(8): 1715-23, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25808863

RESUMO

PURPOSE: Although left atrial (LA) enlargement is a recognized component of athlete's heart, dynamic cavity changes occurring during the training period remain to be elucidated. We aimed to investigate the adaptive changes of LA reservoir, conduit, and active volumes in elite athletes vs. controls and their response to different training loads. METHODS: LA maximum, pre-P, and minimum volumes were assessed in 26 top-level athletes and 23 controls. In athletes, LA volumes were measured at pre-, mid-, end-training, and post-detraining time points using conventional 2D echocardiography. RESULTS: Athletes had larger maximum (27.5 ± 3.2 vs. 20.3 ± 5.8 mL/m(2), p = 0.001), pre-P (11.5 ± 0.9 vs. 9.8 ± 2.2 mL/m(2), p = 0.001), and minimum (6.6 ± 0.9 vs. 5.0 ± 1.2 mL/m(2), p < 0.001) LA indexed volumes, compared with controls. Total and passive emptying volume indices were also larger in athletes compared with controls (18.7 ± 3.1 vs. 15.3 ± 4.9 mL/m(2), p < 0.05 and 13.8 ± 2.9 vs. 10.5 ± 4.6 mL/m(2), p < 0.05, respectively), while active emptying volume was similar (p = 0.74). During training, LA maximum (p < 0.0001), pre-P (p < 0.0001), minimum (p < 0.0001), total (p < 0.005), and passive (p < 0.05) emptying volume indices progressively increased, while active emptying volume (p = 0.10) and E/e' ratio (p = 0.32) remained unchanged. After detraining, LA volume measurements were not different from pre-training ones. End-training left ventricular mass index was the only independent predictor of the respective maximum LA volume (ß = 0.74, p < 0.005). CONCLUSIONS: Top-level athletes exhibit a dynamic morphological and functional LA remodeling, induced by training, with an increase in reservoir and conduit volumes, but stable active volume. LA remodeling is closely associated with left ventricular adaptation to exercise and both completely regress after detraining.


Assuntos
Função do Átrio Esquerdo/fisiologia , Educação Física e Treinamento , Futebol/fisiologia , Adulto , Desempenho Atlético/fisiologia , Ecocardiografia , Humanos , Masculino , Tamanho do Órgão/fisiologia , Volume Sistólico/fisiologia , Função Ventricular Esquerda/fisiologia , Adulto Jovem
12.
J Strength Cond Res ; 29(10): 2758-64, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25785702

RESUMO

In water polo, many of the technical actions and the contacts with the opponent take place in quasi-vertical floating position using 2 types of lower limb actions: the eggbeater kick is used most often in fighting and passing and the breaststroke kick in jumping and throwing. The aim of this study was to identify a new system to evaluate and to train the eggbeater kick movement and to verify its applicability. Twenty amateur players and 22 elite players participated in the study. A jacket, homemade and easy to make, allowing the application of an overload submerged in water but not hindering breathing or mobility, was used. Standard anthropometry and a test consisting of different trials of the eggbeater kick action until exhaustion with an increasing overload (5, 7.5, 10, 12.5, 15, and 17.5 kg) were collected. Time to exhaustion and the overload estimated maximum value (OEMV) at second 2 were determined for each load. Body weight, height, and lower limb muscle performance of the elite and nonelite players were significantly different from each other (p ≤ 0.05). The effectiveness of the different measured variables in both subgroups and that of the OEMV was evaluated with receiver operating characteristic (ROC) curve analysis. Areas under the ROC curve for the different overloads were 0.72 (0.53-0.92) for 5 kg, 0.80 (0.68-0.90) for 7.5 kg, 0.87 (0.77-0.91) for 10 kg, and 0.88 (0.84-0.92) for 12.5 kg overload. Our results show that the test is sensitive enough and therefore can be used to plan and control training and injury recovery.


Assuntos
Extremidade Inferior/fisiologia , Movimento/fisiologia , Condicionamento Físico Humano/métodos , Esportes/fisiologia , Natação/fisiologia , Humanos , Masculino , Esforço Físico/fisiologia , Adulto Jovem
13.
Neurobiol Learn Mem ; 114: 186-92, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24954843

RESUMO

We aimed at investigating rapid effects of plasma cortisol elevations on the episodic memory phase of encoding or retrieval, and on the strength of the memory trace. Participants were asked either to select a word containing the letter "e" (shallow encoding task) or to judge if a word referred to a living entity (deep encoding task). We intravenously administered a bolus of 20mg of cortisol either 5 min before encoding or 5 min before retrieval, in a between-subjects design. The study included only male participants tested in the late afternoon, and neutral words as stimuli. When cortisol administration occurred prior to retrieval, a main effect of group emerged. Recognition accuracy was higher for individuals who received cortisol compared to placebo. The higher discrimination accuracy for the cortisol group was significant for words encoded during deep but not shallow task. Cortisol administration before encoding did not affect subsequent retrieval performance (either for deep or shallow stimuli) despite a facilitatory trend. Because genomic mechanisms take some time to develop, such a mechanism cannot apply to our findings where the memory task was performed shortly after the enhancement of glucocorticoid levels. Therefore, glucocorticoids, through non-genomic fast effects, determine an enhancement in episodic memory if administered immediately prior to retrieval. This effect is more evident if the memory trace is laid down through deep encoding operations involving the recruitment of specific neural networks.


Assuntos
Glucocorticoides/administração & dosagem , Hidrocortisona/administração & dosagem , Memória Episódica , Rememoração Mental/efeitos dos fármacos , Reconhecimento Psicológico/efeitos dos fármacos , Adulto , Método Duplo-Cego , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
14.
J Athl Train ; 2023 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-38069829

RESUMO

CONTEXT: Glenohumeral internal rotation deficit (GIRD) may affect overhead athletes and contribute to shoulder injury. The aim of our study was to assess data on passive shoulder ROM in young elite swimmers and to determine the prevalence of anatomical and pure GIRD (aGIRD and pGIRD) in a large sample size of asymptomatic elite swimmers with a new classification method. OBJECTIVE: to assess data on passive shoulder ROM in young elite swimmers and investigate possible association with anthropometric data and competitive practice routine. DESIGN: Cross-sectional study. SETTING: Research laboratory. PATIENTS OR OTHER PARTICIPANTS: A total of 752 asymptomatic elite swimmers were by voluntary participation (391 males, 361 females; mean age, 15.88 ± 2.31 years). Passive glenohumeral rotational ROM was measured bilaterally to investigate the prevalence of aGIRD and pGIRD. Evaluations were performed with athletes at rest before any training or competition. MAIN OUTCOME MEASURE(S): GIRD and associated aGIRD and pGIRD in elite youth swimmers by identifying a standard classification procedure. RESULTS: GIRD was found in 136 participants (18.1%); aGIRD was present in 28 cases (3.7% of all) whereas pGIRD was observed in 108 cases (14.4% of all). No significant differences were found regarding GIRD between sex, age, age group, years of training, breathing side and distance. Swimmers classified as pGIRD showed significant less dominant Internal rotation, Total range of motion and External rotation gain (P < 0.01) than aGIRD; conversely, aGIRD swimmers shows significant less non-dominant IR, ER and TROM than pGIRD (P < 0.01). CONCLUSIONS: GIRD is a relatively common condition in asymptomatic elite youth swimmers; In order to not overestimate this condition, anatomical and pure GIRD have to be distinguished. While they play a role, the respiratory side, dominant limb, and crawl did not have a significant impact when facing an elite swimmer with GIRD.

15.
Int J Sports Physiol Perform ; 18(2): 171-179, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36626910

RESUMO

PURPOSE: Wetsuits have been shown to change swim biomechanics and, thus, increase performance, but not all athletes are comfortable with their use because of possible modifications in motor coordination. The aim of this study was to evaluate the effects of wetsuit use on biomechanical, physiological, and perceptual variables. METHODS: Eleven national- and international-level triathletes, familiar with wetsuit use, performed 7 × 200-m front crawl at constant preset speed twice, with and without a full wetsuit. The trunk incline (TI) and index of coordination (IdC) were measured stroke by stroke using video analysis. Stroke, breaths, and kick count, and timing (as breathing/kick action per arm-stroke cycle); stroke length (SL); and underwater length were analyzed using inertial-measurement-unit sensors. Heart rate (HR), rating of perceived exertion (RPE), and swimming comfort were monitored during the task. RESULTS: A lower TI; IdC; number of strokes, kicks, and breaths; HR; and RPE for each 200 m were found in wetsuit compared with swimsuit condition. Higher values of SL and underwater length were found in wetsuit, whereas no differences were found in swimming comfort and timing of kicks and breaths. An increase for swimsuit condition in number of strokes and breaths, HR, and RPE was found during the task compared with the first 200 m. CONCLUSION: Wetsuit use reduces TI and, thus, drag; increases propelling proficiency; and shows lower fatigability, without modifying motor coordination, compared with swimsuit use at the same speed. The use of a wetsuit during training sessions is recommended to increase comfort and the positive effects on performance.


Assuntos
Respiração , Natação , Humanos , Fenômenos Biomecânicos , Natação/fisiologia , Braço/fisiologia
16.
Eur J Sport Sci ; 22(3): 390-398, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33487101

RESUMO

The aim of the present study was to test the effect of carbohydrate ingestion, simulating a 10-km open water race competition on energy cost (Csw), perceived exertion (RPE), heart rate (HR), stroke rate (SR) and performance. We hypothesized that carbohydrate ingestion would reduce Csw and RPE in elite open water swimmers (OW-swimmers) and improve performance. Eight elite OW-swimmers swam for 3 × 30 min with 20-s of interval necessary to collect data in the swimming flume at a pre-set pace corresponding to their 10-km race pace, followed by a time to exhaustion test (TTE) at 100% of the peak oxygen uptake (V̇O2peak). During the set, OW-swimmers ingested 45-g of carbohydrates (CHO) in 550-mL of water (8% solution) during each of the two intervals or a placebo solution (PLA). HR, RPE, V̇O2 and SR were measured. Shapiro-Wilk test was used to verify the normal distribution of data. Two-way repeated measures ANOVA and t-test was performed (p < 0.05). A significant difference emerged in TTE between the trials (169.00 ± 91.06 s in CHO; 102.31 ± 57.47 s in PLA). HR, RPE and SR increased during the TTE but did not differ between trials. Csw did not show a significant main effect between the two conditions and in time course in both conditions. CHO ingestion significantly increased TTE at 100% of V̇O2peak after 90-min of swimming at 10-km race pace. These findings indicate that CHO intake during a 10-km open water swimming competition should have a beneficial impact on performance in the final part of the race.


Assuntos
Desempenho Atlético , Natação , Desempenho Atlético/fisiologia , Carboidratos , Suplementos Nutricionais , Humanos , Natação/fisiologia , Água
17.
J Sports Med Phys Fitness ; 62(4): 485-491, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33871237

RESUMO

BACKGROUND: We intended to verify through time-motion analysis the characteristics of the sequences of actions in terms of occurrence during water polo matches: number, duration, and possible relationships with technical-tactical aspects. METHODS: Water polo matches played at the 18th FINA World Championships 2019, Gwangju, South Korea, were chosen for examination, and the analysis involved both single actions and Trains of Actions (ToAs). A ToA is a sequence of actions that occurs during the match without actual game interruption. RESULTS: A total of 1261 game actions were evaluated in the 17 matches analyzed. In 89% of cases the actions occurred in ToAs while in 11% of cases they took place as single actions. On average, each match included 74.4±5.3 actions; of these, only 7.9±3.4 (CI at 95%: lower bound 6.1 and upper bound 9.6) were single actions while 66.2±5.5 occurred in sequences (ToA2=29.6±9.0%; ToA3=26.1±9.7%; ToA4=16.5±10.6%). The winning team performed on average more actions than the losing one (42.1±6.1 vs. 32.0±6.4; effect size: 1.67; P value: 0.001). The ToAs had different compositions, from 2 to 18 actions, and then very different durations, from about 1 minute up to 8 minutes. 66% of goals were scored after ToAs and 34% after single actions. CONCLUSIONS: The study of ToAs provides useful information on the physiological demand of the game, which may help to plan and organize physical training making it as specific as possible. The description of ToAs can help coaches to better define the game scenario and understand which technical and tactical measures are needed to improve game organization.


Assuntos
Desempenho Atlético , Esportes Aquáticos , Desempenho Atlético/fisiologia , Exercício Físico , Humanos , Masculino , República da Coreia
18.
Artigo em Inglês | MEDLINE | ID: mdl-35409934

RESUMO

Despite the common belief that sleep quality at altitude is poor, the scientific evidence to support this notion is still modest. Therefore, the purpose of the present study was to evaluate possible changes of actigraphy-based and subjective sleep parameters in a group of elite open-water swimmers during a 14-day altitude training camp (ATC) at 1500 m. The study subjects were five Olympic-level open-water swimmers (mean age: 25.0 ± 3.2 years; 3 females and 2 males). All subjects wore a wrist activity monitor and filled a sleep diary for 18 consecutive nights, 4 nights before and 14 nights during ATC. The data were then analyzed at four different time points: before ATC (PRE), the first two days of ATC (T1), and after one (T2) and two weeks of ATC (T3). Training load, assessed as the covered distance (km), session rating of perceived exertion (sRPE), and heart rate (HR), was monitored during the week before and the first and second week of ATC. No significant differences in objective and subjective scores of sleep quality were detected, whereas the sleep onset time (p = 0.018; η2p = 0.83, large) and sleep offset time (p < 0.001; η2p = 0.95, large) significantly differed among PRE, T1, T2, and T3: elite athletes started to sleep and woke up ≃ 1 h earlier the first two days of ATC compared to PRE (sleep onset time: p = 0.049; sleep offset time: p = 0.016). Further, an increase in the training volume during the two weeks of the ATC was observed, with the most time spent in a low-intensity regime and an increase in time spent in a high-intensity regime compared to PRE. Sleep quality was not negatively influenced by a 14-day altitude training camp at 1500 m in a group of Olympic-level elite swimmers despite an increase in perceived exertion during training sessions. Nonetheless, early sleep onset and sleep offset times were observed for the first two nights of ATC: elite athletes started to sleep and woke up ≃ 1 h earlier compared to the baseline nights.


Assuntos
Altitude , Água , Adulto , Atletas , Feminino , Humanos , Masculino , Sono/fisiologia , Natação/fisiologia , Adulto Jovem
19.
J Clin Med ; 11(3)2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-35159979

RESUMO

BACKGROUND: Endurance sports practice has significantly increased over the last decades, with a growing proportion of master athletes. However, concerns exist regarding the potential proarrhythmic effects induced by ultra-endurance sports. This study aimed to analyse the acute effects of an ultramarathon race on atrial remodelling and supraventricular arrhythmias in a population of master athletes. METHODS: Master athletes participating in an ultramarathon (50 km, 600 m of elevation gain) with no history of heart disease were recruited. A single-lead ECG was recorded continuously from the day before to the end of the race. Echocardiography and 12-lead resting ECG were performed before and immediately at the end of the race. RESULTS: The study sample consisted of 68 healthy non-professional master athletes. Compared with baseline, P wave voltage was higher after the race (p < 0.0001), and more athletes developed ECG criteria for right atrial enlargement (p < 0.0001). Most of the athletes (97%) had ≥1 premature atrial beats (PAB) during the 24-h monitoring, also organised in triplets (17%) and non-sustained supraventricular tachycardias (NSSVTs) (19%). In contrast, exercise-induced PABs, triplets, and NSSVTs were rare. One athlete developed acute atrial fibrillation during the race. After the race, no significant differences were found in biatrial dimensions. Biatrial function, estimated by peak atrial longitudinal and contraction strains, were normal both before and after the race. CONCLUSIONS: In master athletes running an ultramarathon, acute exercise-induced atrial dysfunction was not detected, and exercise-induced supraventricular arrhythmias were uncommon. These results did not confirm the hypothesis of an acute atrial dysfunction induced by ultra-endurance exercise.

20.
Trends Cardiovasc Med ; 32(5): 299-308, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34166791

RESUMO

INTRODUCTION: The etiology of sudden cardiac death (SCD) in young people continues to attract much attention. This meta-analysis aimed to identify the most frequent causes of SCD in individuals aged ≤35 years, the differences between athletes and non-athletes and geographic areas. METHODS: Studies published between 01/01/1990 and 01/31/2020 and evaluating post-mortem the aetiology of SCD in young individuals (≤35 years) were included. Individuals were divided into athletes and non-athletes. Studies that did not report separate data between athletes and non-athletes were excluded. RESULTS: Thirty-four studies met the inclusion criteria, and a total population of 5,060 victims of SCD were analyzed (2,890 athletes, 2,170 non-athletes). Comparing the causes of SCD between athletes and non-athletes, non-ischemic left ventricular scar (NILVS) (5.1% vs. 1.1%, p=0.01) was more frequent in the former, while coronary artery disease (CAD) (19.6% vs. 9.1%, p=0.009), arrhythmogenic cardiomyopathy (ACM) (11.5% vs. 4.7%, p=0.03) and channelopathies (8.4% vs. 1.9%, p=0.02) were more frequent in the latter. In studies published in the last decade, hypertrophic cardiomyopathy (HCM) (p=0.002), dilated cardiomyopathy (p=0.047), and anomalous origin of coronary arteries (AOCA) (p=0.009) were more frequently the causes of SCD in athletes while aortic dissection (0.022) was the cause in non-athletes. HCM (p=0.01) and AOCA (p=0.004) were more frequently the causes of SCD in the US while ACM (p=0.001), structurally normal heart (p=0.02), and channelopathies (p=0.02) were more frequent in Europe. CONCLUSIONS: Among the causes of SCD, NILVS was the more frequent cause in athletes, while CAD, ACM and channelopathies were more frequent causes in non-athletes. The causes of SCD differ between the US and Europe.


Assuntos
Cardiomiopatia Hipertrófica , Canalopatias , Doença da Artéria Coronariana , Adolescente , Atletas , Canalopatias/complicações , Doença da Artéria Coronariana/complicações , Morte Súbita Cardíaca/epidemiologia , Morte Súbita Cardíaca/etiologia , Ventrículos do Coração , Humanos
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