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1.
Sci Rep ; 14(1): 1113, 2024 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-38212427

RESUMO

Proper functioning of the respiratory system is one of the most important determinants of human health. According to current knowledge, the diaphragmatic breathing pattern seems to be the most favourable. However, recent reports indicate that athletes often have dysfunctional breathing patterns, which may be associated with an increased risk of musculoskeletal injuries. The influence of the type of breathing pattern on the mechanical airways in athletes has not been investigated. The aim of the present study was to determine the characteristics and relationships between breathing patterns and respiratory function in athletes. This study included 69 Polish elite endurance athletes (♂40, ♀29) in different sports disciplines and 44 (♂17, ♀27) healthy nonathletes as a control group. All participants underwent pulmonary function tests (spirometry, plethysmography, diffusion capacity for carbon monoxide) with assessment of breathing patterns by the Hi-Lo test. Inspiratory and expiratory resistance (R) and reactance (X) of the respiratory system at a given frequency (5 Hz, 11 Hz, and 19 Hz) were measured by a noninvasive forced oscillation technique. In this study, almost half of the athletes (44.92%) had dysfunctional breathing patterns, although at a lower rate than that in the control group. Diaphragmatic breathing patterns were characterized by higher spirometric, plethysmographic and DLCO values compared to thoracic or abdominal breathing patterns. Similarly, lower inspiratory reactance at 5 Hz (X5%pred.) was observed in the diaphragmatic pattern compared to the thoracic pattern. A diaphragmatic breathing pattern is associated with better pulmonary function test results. However, this study revealed a dysfunctional breathing pattern in almost half of the athletes. These results suggest that the assessment of breathing patterns and the implementation of breathing exercises in athletes are essential to promote proper breathing patterns.


Assuntos
Pulmão , Respiração , Humanos , Testes de Função Respiratória/métodos , Exercícios Respiratórios/métodos , Atletas
2.
Front Physiol ; 12: 726434, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34566688

RESUMO

Given the previous evidence that breath-hold diving is a cause of physiological stress, this study aimed to determine whether a combination static and dynamic apnea would affect total oxidant status, nitric oxide, heat shock proteins and cardiovascular parameters in elite freedivers. Thirteen finalists of the World and European championships in swimming pool breath-hold diving participated in the study. Whole-body plethysmography and electrocardiography was performed to determine the cardiorespiratory variables at baseline and during the simulation static apnea. An assessment of the heart rate, blood oxygen saturation and biochemical variables was performed before and in response to a combination of a static followed by a dynamic apnea. Static and dynamic breath-holding had a significant effect on oxidative stress, as evidenced by an increase in the total oxidant status/capacity (p < 0.001). The post apnea concentrations of heat shock proteins 27 (HSP27) were significantly elevated (p < 0.03, but total antioxidant status (TAS), HSP90, HSP70, and nitric oxide (NO) changes were not significant. levels under the influence of the static and dynamic breath-hold protocol. A significant positive correlation between HSPs and TAS (r = 0.63; p < 0.05) as well as NO levels was associated with beneficial cardiovascular adaptation. An increase in serum HSP27 levels mediated in nitric oxide levels could explain its important role in improving cardiovascular functions in elite freedivers. Further studies are necessary to explain the exact mechanisms of breath holds training of cardiovascular adaptation responsible for maintaining adequate oxygen supply in elite divers.

3.
J Hum Kinet ; 71: 155-166, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32148580

RESUMO

The aim of this study was to assess the effects of incremental and continuous exercise on the concentration of insulin-like growth factor-1 (IGF-1), growth hormone (GH), testosterone (T), and cortisol (C), as well as to investigate whether increased cardiac dimensions in cyclists were related to changes in these hormones and cardiac biomarkers. The study included 30 elite cyclists divided into two groups, i.e., athletes with left ventricle hypertrophy (a LVH group), and a control group (CG) without LVH. The study protocol included performance of a standard incremental exercise (IncEx) test to measure athletes' maximum power (Pmax), maximum oxygen uptake (VO2max), and lactate threshold (LAT). The IncEx test results were then used to determine the intensity of the continuous exercise (ConEx) test which was performed after the 1-week washout period. Cyclists with LVH and without LVH did not differ in resting hormone concentrations and cardiac biomarkers levels. There was a significant effect of exercise on serum IGF-1 levels (p < 0.05) in the LVH group and a combined effect of the type of exercise and LVH on IGF-1 (p < 0.05). Cyclists with LVH demonstrated higher post exercise T levels recorded in response to exercise compared to the CG (p < 0.01). Significantly higher serum T levels were observed in response to ConEx compared to IncEx in the LVH group and the CG (p < 0.05 and p < 0.05, respectively). In the LVH group, a significant positive correlation between the post-exercise T/C ratio and left ventricular mass index was observed (r = 0.98, p < 0.01). There were no effects of heart hypertrophy on cardiac standard biomarkers. Incremental and continuous exercise caused a marked increase in steroid hormone concentrations and moderate strengthening of insulin growth factors effects. Regular incremental exercise seems to induce beneficial cardiac adaptations via significant increases in the concentration of anabolic factors compared to the same training mode yet with constant exercise intensity.

4.
J Clin Med ; 8(5)2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-31096682

RESUMO

The aim of this study was to evaluate selected parameters of strain and rotation of the left ventricle (the basal rotation (BR) index, the basal circumferential strain (BCS) index, and the global longitudinal strain (GLS) of the left ventricle) in male athletes with physiological cardiac hypertrophy (LVH group), and athletes (non-LVH group) and non-athletes without hypertrophy (control group, CG). They were evaluated using transthoracic echocardiography and speckle tracking echocardiography before and after an incremental exercise test. The LVH group demonstrated lower BR at rest than the non-LVH group (p < 0.05) and the CG (p < 0.05). Physical effort had no effect on BR, nor was this effect different between groups (p > 0.05). There was a combined influence of LVH and physical effort on BR (F = 5.70; p < 0.05) and BCS (F = 4.97; p < 0.05), but no significant differences in BCS and GLS at rest between the groups. A higher BCS and lower GLS after exercise in the LVH group were demonstrated in comparison with the CG (p < 0.05). Left ventricular basal rotation as well as longitudinal and circumferential strains showed less of a difference between rest and after physical effort in subjects with significant myocardial hypertrophy. In conclusion, the obtained results may suggest that echocardiographic assessment of basal rotation and circumferential strain of the left ventricular can be important in predicting cardiac disorders caused by physical effort in individuals with physiological and pathological heart hypertrophy.

5.
J Clin Med ; 8(1)2019 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-30625976

RESUMO

The aim of the present study was to examine the acute effect of an ultra-endurance performance on N-terminal pro-brain natriuretic peptide (NT-proBNP), cardiac specific troponin T (cTnT), creatinine kinase-myocardial band (CK-MB), high sensitive C-reactive protein (hsCRP), ischemia modified albumin (IMA), heart-type fatty acid binding protein (H-FABP) and cardiovascular function. Cardiac biomarkers were evaluated in 14 male ultra-marathoners (age 40 ± 12 years) during a 24 h ultra-marathon at five points (i.e., Pre-race; Marathon, 12-h run, 24-h run, and 48-h post-race). All subjects underwent baseline echocardiography assessment at least 10 days prior to the ultra-marathon and 48 h post-race. The average distance covered during the race was 149.4 ± 33.0 km. Running the ultra-marathon led to a progressive increase in hsCRP and H-FABP concentrations (p < 0.001). CK-MB and cTnT levels were higher after a 24-h run compared to pre-race (p < 0.05). Diastolic function was altered post-race characterized by a reduction in peak early to late diastolic filling (p < 0.01). Running an ultra-marathon significantly stimulates specific cardiac biomarkers; however, the dynamic of secretion of biomarkers linked to myocardium ischemia were differentially regulated during the ultra-marathon race. It is suggested that both exercise duration and intensity play a crucial role in cardiovascular adaptive mechanisms and cause risk of cardiac stress in ultra-marathoners.

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