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1.
Res Q Exerc Sport ; : 1-9, 2020 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-31986105

RESUMO

Purpose: The aim of the study was to verify the agreement between preplanned and executed pacing during a 3-km race and determine whether adjustments are mediated by the rating of perceived exertion (RPE). Method: Thirteen young runners (eight males and five females, 17.5 ± 2.1 and 17.0 ± 1.6 years old, respectively) with national and international experience participated in the study. Before the simulated competition, the athletes informed of their preplanned pacing for the distance through a dashboard with the most common pacing profiles and were also asked to complete a questionnaire communicating their preplanned RPE for each lap of race. During 3-km, heart rate (HR), executed RPE and lap time were recorded. Results: Our results showed no significant association between preplanned and executed pacing (p = .631). Moreover, no significant difference between preplanned and executed RPE was found, including the analysis by laps and phases. RPE and HR increased over time during the race (p < .001). Conclusions: The athletes changed from their preplanned pacing, however, their RPE were similar in the preplanned and executed during the 3-km race. These findings indicate that the RPE could be responsible for adjustments in the pacing strategy.

2.
Int J Cardiol ; 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31761399

RESUMO

BACKGROUND: The optimal cutoff for systolic blood pressure (SBP) level to define high-risk pulmonary embolism (PE) remains to be defined. METHODS: To evaluate the relationship between SBP levels on admission and mortality in patients with acute symptomatic PE, the current study included 39,257 consecutive patients with acute symptomatic PE from the RIETE registry between 2001 and 2018. Primary outcomes included all-cause and PE-specific 30-day mortality. Secondary outcomes included major bleeding and recurrent venous thromboembolism (VTE). RESULTS: There was a linear inverse relationship between admission SBP and 30-day all-cause and PE-related mortality that persisted after multivariable adjustment. Patients in the lower SBP strata had higher rates of all-cause death (reference: SBP 110-129 mmHg) (adjusted odds ratio [OR] 2.9; 95% confidence interval [CI], 2.0-4.2 for SBP <70 mmHg; and OR 1.7; 95% CI, 1.4-2.1 for SBP 70-89 mmHg). The findings for 30-day PE-related mortality were similar (adjusted OR 4.4; 95% CI, 2.7-7.2 for SBP <70 mmHg; and OR 2.6; 95% CI, 1.9-3.4 for SBP 70-89 mmHg). Patients in the higher strata of SBP had significantly lower rates of 30-day all-cause mortality compared with the same reference group (adjusted OR 0.7; 95% CI, 0.5-0.9 for SBP 170-190 mmHg; and OR 0.6; 95% CI, 0.4-0.9 for SBP >190 mmHg). Consistent findings were also observed for 30-day PE-related death. CONCLUSIONS: In patients with acute symptomatic PE, a low SBP portends an increased risk of all-cause and PE-related mortality. The highest mortality was observed in patients with SBP <70 mmHg.

3.
Eur J Sport Sci ; : 1-10, 2019 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-31154905

RESUMO

The aim of this study was to describe the pacing during a 6-h ultramarathon (race 1) and to investigate whether a slow-start affects performance, running kinematic changes, ratings of perceived exertion (RPE) and fatigue (ROF) (race 2). After a critical speed test, participants completed two 6-h ultramarathons. Race 1 (n = 16) was self-paced, whereas in race 2 (n = 10), athletes performed the initial 36 min at speeds 18% below the mean speed of the initial 36 min of race 1. In race 1, participants adopted an inverse sigmoid pacing. Contact times increased after 1 h, and flight times decreased after 30 min (all P ≤ .009); stride length reduced after 1 h 30 min (all P = .022), and stride frequency did not change. Despite the lower speeds during the first 10% of race 2, and higher speeds at 50% and 90%, performance remained unchanged (57.5 ± 10.2 vs. 56.3 ± 8.5 km; P = .298). However, RPE and ROF were lowered for most of race 2 duration (all P < .001). For the comparison of kinematic variables between races, data were normalised by absolute running speed at each time point from 1 h onwards. No differences were found for any of the kinematic variables. In conclusion, decreasing initial speed minimises RPE and ROF, but does not necessarily affect performance. In addition, running kinematic changes do not seem to be affected by pacing manipulation.

4.
Am J Reprod Immunol ; 81(3): e13090, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30624814

RESUMO

PROBLEM: B cells are vital for the normal evolution of pregnancy due to their humoral and possible regulatory activities. Our group and others have documented that circulating B-cell subsets undergo changes from normal late pregnancy to the postpartum period. However, the underlying mechanisms are poorly understood. Therefore, this study examined the degree of B-cell activation in normal pregnancy by analyzing the levels of serum markers in healthy pregnant women during the third trimester of pregnancy, the day of delivery, and the postpartum period. METHOD OF STUDY: A prospective study including pregnant and non-pregnant women attending routine care was undertaken at a hospital clinic. Sociodemographic and clinical data were collected, along with peripheral blood samples. The serum levels of soluble CD23 (sCD23), B-cell-activating factor (BAFF), kappa (κ) and lambda (λ) free light chains (FLC), IgA, IgG, and IgM were quantified. RESULTS: Our study included 43 third trimester pregnant and 35 non-pregnant women. In the pregnant women, the median levels of sCD23, BAFF, IgG, and κ FLC were significantly higher during the postpartum period than during the third trimester of pregnancy. Compared to the non-pregnant women, the third trimester pregnant women had higher median BAFF levels and lower sCD23, IgA, IgG, and FLC levels. CONCLUSION: Changes in serum markers of B-cell kinetics that occur during pregnancy often persist into the postpartum period and affect the secretion of immunoglobulins from different classes. Further studies are needed to clarify the biological significance of our observations.

5.
J Crohns Colitis ; 13(1): 39-49, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30239648

RESUMO

Background and Aims: There is a clinical need to identify biomarkers able to select patients who are most likely to develop aggressive/complicated disease, for early selection for appropriate therapy. Changes in the glycosylation profile of intestinal lymphocytic infiltrate were previously demonstrated to regulate T cell activity, being associated with disease severity in ulcerative colitis [UC] patients. We interrogated whether this heterogeneous expression of branched N-glycans in intestinal inflammatory infiltrate predicts therapy response early in disease course. Methods: The expression levels of the branched N-glycans in colonic biopsies collected around time of diagnosis from a well-characterised cohort of 131 UC patients were correlated with response to standard therapy. Receiver operating characteristic analysis and specificity/sensitivity were determined. Results: Branched N-glycans levels around time of diagnosis predict non-response to conventional therapy with 75% specificity. Moreover, high levels of branched N-glycans predict 78% of UC patients who will display a favourable disease course [exclusively under 5-aminosalicylate therapy for more than 5 years of disease]. The best predictive performance was observed in severe UC patients with Mayo endoscopic subscore 3 and in those that were naïve to therapy. Multivariable analysis revealed that low levels of branched N-glycans and high levels of C-reactive protein [CRP] around time of diagnosis act as independent predictors of non-response to standard therapy. A powerful effect of the combined use of the branched N-glycans and CRP was observed. Conclusions: Our results reveal a potential [glyco]biomarker that predicts, early in the disease course, patients who will fail to respond to standard therapy, benefiting thereby from other therapeutic strategies such as biologics.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/metabolismo , Mucosa Intestinal/metabolismo , Mesalamina/uso terapêutico , Polissacarídeos/metabolismo , Adolescente , Corticosteroides/uso terapêutico , Adulto , Idoso , Biomarcadores/metabolismo , Proteína C-Reativa/metabolismo , Colite Ulcerativa/sangue , Colite Ulcerativa/diagnóstico , Quimioterapia Combinada , Feminino , Humanos , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Curva ROC , Estudos Retrospectivos , Índice de Gravidade de Doença , Falha de Tratamento , Adulto Jovem
6.
Endocrine ; 63(1): 182-187, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30155846

RESUMO

BACKGROUND: Pituitary adenomas and paragangliomas/pheocromocytomas are rare endocrine tumours, which can be sporadic or familial. During many years their coexistence in the same individual was considered a coincidental finding. However, an association between these two entities was recently demonstrated, with the possible involvement of SDHx genes. CASE REPORT: We describe a 57-year-old female patient, who was under surveillance since 1997 for a malignant paraganglioma with vertebral bone metastasis, and harboured a germline frameshift mutation in exon 6 of SDHB gene [c.587-591DelC]. Seventeen years later, she was diagnosed with acromegaly and underwent transesphenoidal endoscopic resection of a somatotropinoma. Three months after surgery she started treatment with lanreotide for residual disease. Despite initial good response, she developed resistance to first generation of somatostatin analogues and treatment had to be switched to pegvisomant. In the immunohistochemical staining, the pituitary adenoma was positive for SDHA expression, while SDHB showed an heterogeneous staining pattern, with areas markedly positive and others with positive and negative cells. CONCLUSIONS: Our findings provide useful data for understanding the link between paragangliomas/pheocromocytomas and somatotropinomas. While we confirm the well-established link between SDHB mutations and paragangliomas/pheocromocytomas, particularly with malignant paragangliomas, the preservation-at least partially-of SDHB expression in the somatotropinoma tissue does not allow drawing definite conclusions about the involvement of the SDHB mutation in pituitary adenoma.


Assuntos
Adenoma/genética , Neoplasias das Glândulas Endócrinas/genética , Mutação da Fase de Leitura/genética , Adenoma Hipofisário Secretor de Hormônio do Crescimento/genética , Paraganglioma/genética , Succinato Desidrogenase/genética , Acromegalia/etiologia , Adenoma/complicações , Adenoma/patologia , Terapia Combinada , Neoplasias das Glândulas Endócrinas/complicações , Neoplasias das Glândulas Endócrinas/patologia , Éxons/genética , Feminino , Mutação em Linhagem Germinativa , Adenoma Hipofisário Secretor de Hormônio do Crescimento/complicações , Adenoma Hipofisário Secretor de Hormônio do Crescimento/patologia , Humanos , Pessoa de Meia-Idade , Paraganglioma/complicações , Paraganglioma/patologia , Linhagem
7.
Artigo em Inglês | LILACS-Express | ID: biblio-1042021

RESUMO

Abstract It is necessary to clarify if BM and track and field performance can modulate the perception about RPE-session. The purpose of the present study was to verify if biological maturity and track and field-specific performance can be associated with training load (RPE-session method). Seventy-five young athletes (13-15 years old) of both genders participated in the present study. The experimental protocol lasted seven consecutive days. Performance tests (75-m running, long jump, 250-m running, shot put and 1000-m running) were made on the first day. After 48 hours, five days of track and field training it was prescribed, each day represents a training of each performance test. All training sessions had the same duration (120 min). The value of the training load was obtained multiplying the RPE value with training session duration (in minutes). For girls, the training load of 250-m training was correlated with biological maturity (r = -0.36, p = 0.02, n = 37) and specific performance (r = 0.33, p = 0.04, n = 37). All other analyzes indicate that biological maturity and track and field-specific performance do not influence the training load based on RPE-session method. Training load based on RPE-session is not influenced by biological maturity and track and field-specific performance, therefore can be used to control the training load of young track and field athletes. To girls it is necessary a care to control the training sessions intensity of 250-m running.


Resumo É necessário esclarecer se a maturação biológica e o desempenho no atletismo podem modular a PSE da sessão. O objetivo do presente estudo foi verificar se a maturidade biológica e o desempenho específico no atletismo podem estar associados à carga de treinamento (método de PSE da sessão). Setenta e cinco jovens atletas (13-15 anos) de ambos os sexos participaram do presente estudo. O protocolo experimental durou sete dias consecutivos. Testes de desempenho (75 m de corrida, salto em distância, 250 m de corrida, arremesso de peso e 1000 m de corrida) foram feitos no primeiro dia. Após 48 horas, cinco dias de treinamento de atletismo foram prescritos, cada dia representa um treinamento de cada teste de desempenho. Todas as sessões de treinamento tiveram a mesma duração (120 min). O valor da carga de treinamento foi obtido multiplicando o valor do PSE com a duração da sessão de treinamento (em minutos). Para as meninas, a carga de treinamento de 250 m foi correlacionada com a maturidade biológica (r = -0,36, p = 0,02, n = 37) e desempenho específico (r = 0,33, p = 0,04, n = 37). Todas as outras análises indicam que a maturidade biológica e o desempenho específico no atletismo não influenciam a carga de treinamento com base no método da PSE da sessão. A carga de treinamento com base na PSE da sessão não é influenciada pela maturidade biológica e desempenho específico no atletismo, portanto, pode ser usada para controlar a carga de treinamento de jovens atletas de atletismo. Para as meninas é necessário cuidado para controlar a intensidade das sessões de treino de 250m de corrida.

8.
Arch Endocrinol Metab ; 62(5): 530-536, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30462806

RESUMO

OBJECTIVE: The aim was to evaluate the quality of life (HRQoL) in women with subclinical hypothyroidism (sHT) after 16 weeks of endurance training. SUBJECTS AND METHODS: In the first phase, a cross-sectional study was conducted in which 22 women with sHT (median age: 41.5 (interquartile range: 175) years, body mass index: 26.2 (8.7) kg/m2, thyroid stimulating hormone > 4.94 mIU/L and free thyroxine between 0.8 and 1.3 ng/dL were compared to a group of 33 euthyroid women concerned to HRQoL. In the second phase, a randomized clinical trial was conducted where only women with sHT were randomly divided into two groups: sHT-Tr (n = 10) - participants that performed an exercise program - and sHT-Sed (n = 10) - controls. Exercise training consisted of 60 minutes of aerobic activities (bike and treadmill), three times a week, for 16 weeks. The HRQoL was assessed by the SF-36 questionnaire in the early and at the end of four months. RESULTS: Women with sHT had lower scores on functional capacity domain in relation to the euthyroid ones (770 ± 23.0 vs. 88.8 ± 14.6; p = 0.020). The sHT-Tr group improved functional capacity, general health, emotional aspects, mental and physical component of HRQoL after training period, while the sHT-Sed group showed no significant changes. CONCLUSION: After 16 weeks of aerobic exercise training, there were remarkable improvements in HRQoL in women with sHT.


Assuntos
Terapia por Exercício/métodos , Exercício/fisiologia , Hipotireoidismo/terapia , Qualidade de Vida , Adulto , Análise de Variância , Autoanticorpos/sangue , Estudos Transversais , Feminino , Humanos , Hipotireoidismo/fisiopatologia , Iodeto Peroxidase/sangue , Iodeto Peroxidase/imunologia , Medições Luminescentes/métodos , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Inquéritos e Questionários , Tireotropina/sangue , Tiroxina/sangue , Fatores de Tempo , Resultado do Tratamento
9.
Arch. endocrinol. metab. (Online) ; 62(5): 530-536, Oct. 2018. tab
Artigo em Inglês | LILACS-Express | ID: biblio-983789

RESUMO

ABSTRACT Objective: The aim was to evaluate the quality of life (HRQoL) in women with subclinical hypothyroidism (sHT) after 16 weeks of endurance training. Subjects and methods: In the first phase, a cross-sectional study was conducted in which 22 women with sHT (median age: 41.5 (interquartile range: 175) years, body mass index: 26.2 (8.7) kg/m2, thyroid stimulating hormone > 4.94 mIU/L and free thyroxine between 0.8 and 1.3 ng/dL were compared to a group of 33 euthyroid women concerned to HRQoL. In the second phase, a randomized clinical trial was conducted where only women with sHT were randomly divided into two groups: sHT-Tr (n = 10) - participants that performed an exercise program - and sHT-Sed (n = 10) - controls. Exercise training consisted of 60 minutes of aerobic activities (bike and treadmill), three times a week, for 16 weeks. The HRQoL was assessed by the SF-36 questionnaire in the early and at the end of four months. Results: Women with sHT had lower scores on functional capacity domain in relation to the euthyroid ones (770 ± 23.0 vs. 88.8 ± 14.6; p = 0.020). The sHT-Tr group improved functional capacity, general health, emotional aspects, mental and physical component of HRQoL after training period, while the sHT-Sed group showed no significant changes. Conclusion: After 16 weeks of aerobic exercise training, there were remarkable improvements in HRQoL in women with sHT.

10.
Dis Model Mech ; 11(8)2018 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-29991569

RESUMO

Cancer stem cells are a subpopulation of cells within a tumour believed to confer resistance to standard cancer therapies. Although many studies have addressed the specific mechanisms of tumour recurrence driven by cancer stem cells, cellular metabolism is an often-neglected attribute. The metabolic features of cancer stem cells are still poorly understood, and they thus constitute a promising field in cancer research. The findings published so far point to a distinct metabolic phenotype in cancer stem cells, which might depend on the cancer type, the model system used or even the experimental design, and several controversies still need to be tackled. This Review describes the metabolic phenotype of cancer stem cells by addressing the main metabolic traits in different tumours, including glycolysis and oxidative, glutamine, fatty acid and amino acid metabolism. In the context of these pathways, we also mention the specific alterations in metabolic enzymes and metabolite levels that have a role in the regulation of cancer stemness. Determining the role of metabolism in supporting resistance to therapy driven by cancer stem cells can raise the opportunity for novel therapeutic targets, which might not only eliminate this resistant population, but, more importantly, eradicate the whole tumour in a relapse-free scenario.


Assuntos
Células-Tronco Neoplásicas/metabolismo , Animais , Humanos , Modelos Biológicos , Terapia de Alvo Molecular , Células-Tronco Neoplásicas/patologia , Fenótipo , Células-Tronco/metabolismo
12.
Percept Mot Skills ; 125(3): 566-580, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29558842

RESUMO

This study compared the effects of different conditioning activities on the 100-m dash performance of 11 male, high school track and field athletes (mean age = 16.3; SD = 1.2 years). Participants performed a 100-m dash seven minutes after each of four randomized conditioning protocols, with each condition and 100-m dash separated by 3-10 days. The conditioning protocols were (a) control, no conditioning activity; (b) weighted plyometric, three sets of 10 repetitions of alternate leg bounding with additional load of 10% of the body mass; (c) free sprint, two 20-m sprints; and (d) resisted sprint (RS), two 20-m resisted sprints using an elastic tubing tool. We obtained session ratings of perceived exertion (SRPE) immediately after each conditioning protocol. There were no significant differences between any of the three experimental conditioning activities on 100-m sprint time, but the RS protocol improved 100-m sprint time compared with the control (no conditioning) protocol ( p < .001). The RS also led to greater sprint velocity and higher SRPE compared with the control condition ( p < .01). There was no significant association between SRPE and 100-m performance ( p = .77, r = .05). These results suggest a benefit for young male track and field athletes to the elastic tubing warm-up activities prior to the 100-m dash.


Assuntos
Atletas , Desempenho Atlético/fisiologia , Condicionamento Físico Humano/fisiologia , Estudantes , Atletismo/fisiologia , Adolescente , Humanos , Masculino , Condicionamento Físico Humano/métodos , Distribuição Aleatória , Instituições Acadêmicas
13.
Head Neck ; 40(6): 1271-1278, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29469959

RESUMO

BACKGROUND: Nuclear factor erythroid 2-like 2 (NFE2L2) encodes Nrf2, transcription factor of antioxidative genes. In the presence of reactive oxygen species, Keap1 (Kelch-ECH-associating protein-1) inhibitor complex undergoes conformational changes disrupting Keap1-Nrf2 binding and Nrf2 translocates into nucleus. We evaluated the presence of mutations in NFE2L2 and KEAP1 in papillary thyroid carcinomas (PTCs) and correlated them with clinical presentation. METHODS: Coding regions of NFE2L2 and KEAP1 were sequenced in 131 patients with PTC. Clinical and histopathological features were analyzed. Immunohistochemical analysis of Nrf2 expression was performed in mutated carcinomas. RESULTS: Although no mutations were found in NFE2L2, missense mutations in KEAP1 were observed in 6 patients with PTC (4.6%). Immunohistochemistry showed increased Nrf2 expression in nuclei of all mutated carcinomas, which presented poor prognostic features in histopathology. CONCLUSION: We identified mutations in KEAP1 associated with Nrf2 overexpression in PTC. Mutations favored disruption of inhibitory interaction Nrf2-Keap1 to enable increased antioxidant Nrf2 activity, possibly with prognostic consequences.


Assuntos
Proteína 1 Associada a ECH Semelhante a Kelch/genética , Mutação/genética , Fator 2 Relacionado a NF-E2/genética , Câncer Papilífero da Tireoide/genética , Neoplasias da Glândula Tireoide/genética , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fator 2 Relacionado a NF-E2/metabolismo , Câncer Papilífero da Tireoide/patologia , Câncer Papilífero da Tireoide/cirurgia , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/cirurgia , Tireoidectomia
14.
Res Q Exerc Sport ; 89(1): 47-56, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29333996

RESUMO

PURPOSE: This study aimed to compare the energy expenditure and intensity of active video games to that of treadmill walking in children and adolescents. METHOD: Seventy-two boys and girls (aged 8-13 years) were recruited from local public schools. Energy expenditure and heart rate were measured during rest, during 3-km/hr, 4-km/hr, and 5-km/hr walks, and during active games (Adventure, Boxing I, Boxing II, and Dance). During walking and active games, we also assessed physical activity using an accelerometer. RESULTS: The energy expenditure of the active games Adventure, Boxing I, Boxing II, and Dance was similar to that of treadmill walking at 5 km/hr in boys and girls. Heart rate was significantly higher for the game Adventure compared with walking at 3 km/hr, 4 km/hr, and 5 km/hr and the game Dance in both genders. The heart rate of girls during the games Adventure and Dance was significantly higher compared with boys. There was a statistically significant difference (p < .05, with an effect size ranging from 0.40 to 3.54) in the counts·min-1, measured through accelerometry, between activities. CONCLUSION: XBOX 360 Kinect games provide energy expenditure and physical activity of moderate intensity for both genders. The use of active video games can be an interesting alternative to increase physical activity levels.


Assuntos
Metabolismo Energético , Exercício , Jogos de Vídeo , Adolescente , Metabolismo Basal , Criança , Feminino , Frequência Cardíaca , Humanos , Masculino , Consumo de Oxigênio , Caminhada/fisiologia
15.
Blood Press Monit ; 23(2): 64-70, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29227294

RESUMO

AIM: This study aimed to investigate the clinic and 24-h postexercise hypotension (PEH) after a moderate-intensity arm crank exercise session in individuals with traumatic lower-limb amputation. PARTICIPANTS AND METHODS: Nine men (46±17 years) with unilateral traumatic lower-limb amputation participated in two experimental sessions conducted randomly: an aerobic exercise (EXE: arm crank ergometer, 30 min) or a control session (CON: participants remained seated on the cycle ergometer, 30 min). Clinic and 24-h systolic, diastolic, and mean blood pressure (BP) response were measured after both sessions. The clinical measurements of blood flow and forearm vascular resistance (FVR) were also performed. RESULTS: Compared with the preintervention period, the BP levels did not change in the CON session. However, EXE resulted in a significant hypotensive effect in systolic (-10±0.9 mmHg, P≤0.05), diastolic (-11±1.5 mmHg, P≤0.05), and mean BP (-11±1.2 mmHg, P≤0.05) during the entire postexercise period. The PEH was accompanied by a decreased FVR over the entire postintervention period (P≤0.05). Significant reductions were found for 24-h average systolic, diastolic, and mean BP levels (P=0.03, 0.01, and 0.02, respectively) following EXE compared with the CON session. CONCLUSION: These results showed, for the first time, that individuals with traumatic lower-limb amputation presented immediate and 24-h PEH after a single bout of arm crank exercise testing. The PEH at the clinic condition was justified, at least in part, by the reduction in peripheral FVR.


Assuntos
Amputação Traumática/fisiopatologia , Pressão Sanguínea , Hipertensão/fisiopatologia , Hipotensão/fisiopatologia , Extremidade Inferior/lesões , Adulto , Amputação Traumática/complicações , Amputação Traumática/terapia , Braço/fisiopatologia , Estudos Cross-Over , Exercício , Terapia por Exercício , Humanos , Hipertensão/complicações , Hipertensão/terapia , Hipotensão/etiologia , Extremidade Inferior/fisiopatologia , Masculino , Pessoa de Meia-Idade , Resistência Vascular
16.
J Sports Med Phys Fitness ; 58(6): 810-815, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28480693

RESUMO

BACKGROUNDː The aim of the present study was to identify determinant variables on 800-m running performance in young male athletes derived from field tests and biological maturity. METHODSː A total of 89 athletes, aged between 13 and 15 years old, performed a 800-m running trial and a battery of tests which involved anthropometric measurements, a running anaerobic test (RAST), a flexibility test (sit-and-reach), a counter movement jump test and progressive test for aerobic fitness evaluation. A stepwise multiple regression model selected three independent variables to explain the variance in 800-m running performance trial: peak of aerobic speed (PAS), total time of all sprints (RAST) and predicted mature stature (PMS). RESULTSː The PAS speed explained 73.6% (P<0.01) of the variance, whereas the RAST and PMS accounted for additional 7.7% (P<0.01) and 0.9% (P<0.05), respectively. Taken together, these variables explained 82.2% of the overall 800-m running performance. CONCLUSIONSː The results indicate that the 800-m running performance might be explained mainly by aerobic (PAS) and anaerobic metabolisms (RAST). Beyond the traditional variables of performance in 800-m running trial, the biological maturity must be considered in regard of endurance performance of young athletes.


Assuntos
Atletas , Desempenho Atlético/fisiologia , Teste de Esforço , Corrida/fisiologia , Adolescente , Fatores Etários , Limiar Anaeróbio/fisiologia , Estatura , Humanos , Masculino , Consumo de Oxigênio/fisiologia , Puberdade/fisiologia
17.
Ann Noninvasive Electrocardiol ; 23(3): e12521, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29219220

RESUMO

BACKGROUND: Postexercise heart rate (HR) recovery presents an exponential decay, with two distinct phases: a fast phase, characterized by abrupt decay of HR, and determined by parasympathetic reactivation; and a slow phase, characterized by gradual decay of HR, and predominantly determined by sympathetic withdrawal. Although several methods have been proposed to assess postexercise HR recovery, none of those methods selectively assesses the time of transition from the fast to the slow phase of the HR recovery curve (HRRPT ), and the magnitude of decay prior to (HRRFP ) and after this point (HRRSP ). Therefore, the aim of the present study was to propose a method to identify HRRPT , HRRFP , and HRRSP and to verify the effects of exercise intensity and physical fitness on such parameters. METHODS: Ten healthy young participants (24 ± 3 years; 23.6 ± 1.7 kg/m2 ) randomly underwent two exercise sessions (30 min of cycling), at moderate (MI) and high intensity (HI); followed by 5 min of inactive recovery. HR was continuously recorded during the sessions. The algorithm for HRRPT analysis was written in Python and is freely available online. RESULTS: HRRPT and HRRSP were increased in HI session compared with MI (81 ± 24 vs. 60 ± 20 s; 8 ± 10 vs. 1 ± 5 bpm; p = .04), and there was no difference in HRRFP between sessions (49 ± 15 vs. 46 ± 10 bpm; p = .17). In addition, HRRPT for MI exercise session was significantly and negatively associated with VO2max (r = -0.85, p < .05). CONCLUSION: The method herein presented was sensitive to exercise intensity, and partially responsive to aerobic fitness. Next studies should perform the pharmacological and clinical validations of the method.


Assuntos
Eletrocardiografia/métodos , Frequência Cardíaca/fisiologia , Aptidão Física/fisiologia , Adulto , Humanos , Masculino , Valores de Referência , Adulto Jovem
18.
Motriz (Online) ; 24(4): e101848, 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-976255

RESUMO

The aims of this study were: i) to verify whether player internal load (PIL) monitored via heart rate (HR) varies with game-time and playing position; ii) whether intermittent running capacity (IRC) is related to the maintenance of within-match PIL in elite youth (U-15) soccer players. Method: Twenty-one elite soccer players (14±0.5 yrs, 172±7 cm, 63±6 kg) had their heart rate monitored (beats/min) in five matches and were tested twice for IRC (Yo-YoIR2, distance [m]) over a seven-week competitive season. Percentage of maximal heart rate (%HRmax) and time spent (TS%) in five zones (Z1[<70%]; Z2[71-85%]; Z3[86-90%]; Z4[91-95%] and Z5[>96%]) were our PIL indexes. Data from three complete games in the same position of each player were analyzed and matches halves, time intervals (T1 to T6), and playing positions (fullbacks, central defenders and forwards [N=5 each], midfielders [N=6]) were compared, and the relationship between IRC and within-match PIL was determined. Results: PIL was higher in 1st (86±3%) than in the 2nd half (84±4%; p<.001). The 2nd half had more TS% in Z1 and Z2 (p<.05). PIL in T4 was the lowest (p<.01), and in T6, it was lower than T1 and T2 (p<.01). Fullbacks and midfielders showed higher PIL and higher TS% in Z4 (p<.05) than the other positional roles. The average IRC correlated with PIL in T6 (r=.56, p<.01) only. Conclusion: In conclusion, the internal load in elite youth (U-15) soccer players varies with game-time and playing position; and their IRC is related to the maintenance of within-match PIL.(AU)


Assuntos
Humanos , Masculino , Adolescente , Futebol/fisiologia , Desempenho Atlético/fisiologia , Frequência Cardíaca/fisiologia , Atletas , Esportes Juvenis
19.
Chronobiol Int ; 34(10): 1354-1365, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29053066

RESUMO

Incidence of cardiovascular events follows a circadian rhythm with peak occurrence during morning. Disturbance of autonomic control caused by exercise had raised the question of the safety in morning exercise and its recovery. Furthermore, we sought to investigate whether light aerobic exercise performed at night would increase HR and decrease HRV during sleep. Therefore, the aim of this study was to test the hypothesis that morning exercise would delay HR and HRV recovery after light aerobic exercise, additionally, we tested the impact of late night light aerobic exercise on HR and HRV during sleep in sedentary subjects. Nine sedentary healthy men (age 24 ± 3 yr; height 180 ± 5 cm; weight 79 ± 8 kg; fat 12 ± 3%; mean±SD) performed 35 min of cycling exercise, at an intensity of first anaerobic threshold, at three times of day (7 a.m., 2 p.m. and 11 p.m.). R-R intervals were recorded during exercise and during short-time (60 min) and long-time recovery (24 hours) after cycling exercise. Exercise evoked increase in HR and decrease in HRV, and different times of day did not change the magnitude (p < 0.05 for time). Morning exercise did not delay exercise recovery, HR was similar to rest after 15 minutes recovery and HRV was similar to rest after 30 minutes recovery at morning, afternoon, and night. Low frequency power (LF) in normalized unites (n.u.) decreased during recovery when compared to exercise, but was still above resting values after 60 minutes of recovery. High frequency power (HF-n.u.) increased after exercise cessation (p < 0.05 for time) and was still below resting values after 60 minutes of recovery. The LF/HF ratio decreased after exercise cessation (p < 0.05 for time), but was still different to baseline levels after 60 minutes of recovery. In conclusion, morning exercise did not delay HR and HRV recovery after light aerobic cycling exercise in sedentary subjects. Additionally, exercise performed in the night did change autonomic control during the sleep. So, it seems that sedentary subjects can engage physical activity at any time of day without higher risk.


Assuntos
Ritmo Circadiano/fisiologia , Exercício/fisiologia , Frequência Cardíaca/fisiologia , Comportamento Sedentário , Adulto , Teste de Esforço , Humanos , Masculino , Descanso/fisiologia , Fatores de Tempo , Adulto Jovem
20.
Rev. bras. med. esporte ; 23(5): 390-393, set.-out. 2017. tab, graf
Artigo em Português | LILACS-Express | ID: biblio-898995

RESUMO

RESUMO Introdução: A frequência cardíaca fornece informações úteis para os treinamentos de marcha atlética. Objetivo: O objetivo do estudo foi analisar o comportamento da frequência cardíaca (FC) e seus pontos de inflexão (PIFC) e deflexão (PDFC) em teste progressivo de marcha atlética (TPMA) antes e depois de 20 sessões de treinamento. Métodos: Participaram 13 jovens atletas (12,46 ± 1,61 anos, 44,29 ± 10,25 kg, 157,93 ± 12,03 cm, 24,39 ± 7,60 %G). O TPMA foi realizado em uma pista oficial de atletismo, antes e depois do treinamento. Os dados de FC e carga foram plotados a cada minuto para identificação dos PIFC e PDFC. Resultados: A FC apresentou comportamento sigmoide, com identificação dos pontos de transição (PT), sendo no pré-treinamento: a) oito sujeitos PIFC (5,31 km·h-1; 125 bpm) e PDFC (7,63 km·h-1; 169 bpm); b) um sujeito somente PIFC (7,00 km·h-1; 149 bpm); c) um sujeito somente PDFC (8,00 km·h-1; 170 bpm); d) três sujeitos sem detecção de PT e no pós-treinamento: a) em 12 sujeitos PIFC (5,46 km·h-1; 125 bpm) e PDFC (7,75 km·h-1; 168 bpm); b) um sujeito somente PDFC (7,50 km·h-1; 184 bpm). O PIFC foi encontrado em carga significativamente inferior ao PDFC no pré (p < 0,001) e no pós-treinamento (p < 0,001). Quando comparamos o PIFC e o PDFC pré e pós, não encontramos diferença significativa, seja em relação à carga (p = 0,87 e p = 0,61) ou FC (p = 0,60 e p = 0,99). Conclusão: Conclui-se que a FC tem relação curvilínea com a carga, sendo possível detectar os seus pontos de transição em TPMA.


ABSTRACT Introduction: Heart rate provides useful information for race walking training. Objective: The objective of study was to analyze the behavior of heart rate (HR) and inflection points (HRIP) and deflection points (HRDP) in a progressive test of race walking (PTRW) before and after 20 training sessions. Methods: Participants were 13 young athletes (12.46 ± 1.61 years, 44.29 ± 10.25 kg, 157.93 ± 12.03 cm, 24.39 ± 7.60 F%). The PTRW was held at an official athletics track before and after training. The HR data and load were plotted every minute to identify the HRIP and HRDP. Results: The HR showed sigmoid behavior with the identification of transition points (TP), being in the pre-training: a) eight subjects HRIP (5.31 km·h-1; 125 bpm)and HRDP (7.63 km·h-1; 169 bpm); b) one subject only HRIP (7.00 km·h-1; 149 bpm); c) one subject only HRDP (8,00 km·h-1; 170 bpm); d) three subjects had no TP observed, and post-training: a) 12 subjects HRIP (5.46 km·h-1; 125 bpm) and HRDP (7.75 km·h-1; 168 bpm); b) one subject HRDP (7.50 km·h-1; 184 bpm). The HRIP was found to be significantly lower than the HRDP in pre-training (p<0.001) and post-training (p<0.001). When we compared HRIP and HRDP in the pre- and post-training we found no significant difference either in relation to the load (p=0.87 and p=0.61) or HR (p=0.60 and p=0.99). Conclusion: It is concluded that the HR has curvilinear relation with the load, and that it is possible to detect its transition points during PTRW.


RESUMEN Introducción: La frecuencia cardiaca proporciona información útil para los entrenamientos de marcha atlética. Objetivo: El objetivo del estudio fue analizar el comportamiento de la frecuencia cardiaca (FC) y sus puntos de inflexión (PIFC) y de deflexión (PDFC) en prueba progresiva de marcha atlética (PPMA) antes y después de 20 sesiones de entrenamiento. Métodos: Participaron 13 atletas jóvenes (12,46 ± 1,61 años, 44,29 ± 10,25 kg, 157,93 ± 12,03 cm, 24,39 ± 7,60 %G). El PPMA fue realizado en una pista oficial de atletismo antes y después del entrenamiento. Los datos de FC y carga fueron trazados cada minuto para identificación de PIFC y PDFC. Resultados: La FC presentó comportamiento sigmoideo, con identificación de los puntos de transición (PT), siendo en el pre-entrenamiento: a) ocho sujetos PIFC (5,31 km·h-1, 125 lpm) y PDFC (7,63 km·h-1; 169 lpm); b) un sujeto solamente PIFC (7,00 km·h-1; 149 lpm); c) un sujeto solamente PDFC (8,00 km·h-1, 170 lpm); d) tres sujetos sin detección de PT y post-entrenamiento: a) 12 sujetos PIFC (5,46 km·h-1, 125 lpm) y PDFC (7,75 Km·h-1; 168 lpm); b) un sujeto solamente PDFC (7,50 km·h-1, 184 lpm). El PIFC fue encontrado en carga significativamente inferior que el PDFC en el pre (p < 0,001) y en el post-entrenamiento (p < 0,001). Al comparar el PIFC y el PDFC pre y post-entrenamiento, no se encontró ninguna diferencia significativa, sea en relación a la carga (p = 0,87 y p = 0,61) o FC (p = 0,60; p = 0,99). Conclusión: Se concluye que la FC tiene relación curvilínea con la carga, siendo posible detectar sus puntos de transición en PPMA.

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