Efeitos do exercício físico sobre a pressão arterial, variabilidade da frequência cardíaca e na função vascular de indivíduos com e sem hipertensão
Data
2021-10-15
Autores
Montrezol, Fábio Tanil 
Orientadores
Medeiros, Alessandra
Tipo
Tese de doutorado
Título da Revista
ISSN da Revista
Título de Volume
Resumo
As doenças cardiovasculares são as principais causa de morte no mundo e uma das principais causas destas patologias é a hipertensão arterial sistêmica. O envelhecimento é acompanhado de aumentos pressóricos. O senescente é acometido de desequilíbrio simpato-vagal, a deterioração do controle autonômico cardíaco é linear com a idade. Contudo, estudos mostram que ao tratar a hipertensão com exercício físico há um grande impacto na redução de mortalidade por doenças cardiovasculares. Porém, os mecanismos envolvidos na hipotensão pós exercício físico não estão bem claros. Também carece de mais estudos, a eficácia do exercício físico na redução do risco de eventos isquêmicos, assim como sua eficácia na atenuação da disfunção vascular. A fim de avaliar estes desfechos do exercício físico, o presente estudo foi dividido em duas fases, a primeira conduzida no Brasil com o objetivo de verificar o efeito de uma sessão aguda de exercício aeróbio sobre o balanço simpato-vagal, pressão arterial e função vascular de indivíduos hipertensos (estudo I). E a segunda etapa conduzida na Liverpool John Moores University com o objetivo de avaliar o efeito do exercício resistido agudo em atenuar a disfunção vascular de adultos jovens e idosos saudáveis (estudo II). Para tanto, no estudo I foram recrutados indivíduos hipertensos com idade entre 40 e 55 e também entre 60 e 80 anos. Avaliou-se a pressão arterial pela monitorização ambulatorial da pressão arterial, variabilidade da frequência cardíaca e também a reatividade vascular carotídea. Todos indivíduos foram submetidos a avaliação cardiorrespiratória a fim de estabelecer a velocidade referente ao primeiro limiar ventilatório, e de forma aleatória a duas sessões uma de exercício agudo e outra controle. Observou-se melhora da função vascular em idosos e adultos jovens, a qual foi aferida pela reatividade vascular carotídea após sessão aguda de exercício aeróbio [(Grupo jovem= 1,41±1,78 vs. 3,04±1,20, pré vs. pós respectivamente) e (Grupo idoso= 0,31±1,92 vs. 2,27±1,43 pré vs. pós respectivamente)]. Para o estudo II foram recrutados homens saudáveis com idade entre 20 e 40 e também entre 50 e 70 anos de idade. Os indivíduos foram submetidos a lesão temporária por isquemia reperfusão a fim de reduzir a função vascular. Logo após a indução da lesão por isquemia reperfusão (IRI), os indivíduos foram submetidos a três sessões, (controle, agachamento e condicionamento pré isquêmico), a função vascular foi avaliada pela dilatação mediada pelo fluxo (FMD) A função vascular foi reestabelecida apenas em idosos após uma sessão aguda de exercício resistido (Grupo idoso = 4,21±1,67 vs. 3,64±1,26 pré vs. pós respectivamente). Concluímos então que o exercício físico independente do tipo é uma estratégia eficaz para melhorar a função vascular, contudo pode haver uma relação idade-dependente com o tipo do exercício.
Cardiovascular diseases are the main cause of death worldwide and one of the main causes of these pathologies is systemic arterial hypertension. Aging is accompanied by pressure increases. The senescent is affected by sympathovagal imbalance, the deterioration of cardiac autonomic control is linear with age. However, studies show that treating hypertension with physical exercise has a great impact on reducing mortality from cardiovascular diseases. However, the mechanisms involved in postexercise hypotension are not clear. There is also a need for further studies on the effectiveness of physical exercise in reducing the risk of ischemic events, as well as in attenuating vascular dysfunction. In order to evaluate these physical exercise outcomes, the present study was divided into two phases, the first one conducted in Brazil with the objective of verifying the effect of an acute aerobic exercise session on the sympathovagal balance, blood pressure and vascular function of hypertensive subjects (study 1). And a second one conducted at Liverpool John Moores University aiming to evaluate the effect of acute resistance exercise in attenuating vascular dysfunction in young and elderly adults (study 2). Therefore, in study 1, hypertensive individuals aged between 40 and 55 and also between 60 and 80 years were recruited. Blood pressure was assessed by ambulatory blood pressure monitoring, heart rate variability and also carotid vascular reactivity. All individuals were submitted to cardiorespiratory assessment in order to establish the speed related to the first ventilatory threshold, and randomly to two sessions, one acute exercise session and a control session. Improvement in endothelial function was observed in elderly and young adults, which was measured by carotid vascular reactivity after an acute session of aerobic exercise [(Youth group= 1.41±1.78 vs. 3.04±1.20, pre vs post respectively) and (Elderly group = 0.31±1.92 vs. 2.27±1.43 pre vs post respectively)]. For study 2, healthy men aged between 20 and 40 and also between 50 and 70 years of age were recruited. Subjects underwent temporary ischemia reperfusion injury (IRI) in order to reduce vascular function. After ischemia reperfusion injury induction, subjects underwent three sessions (control, squat and pre-ischemic conditioning), in order to assess vascular function flow-mediated dilation (FMD) method was employed. Vascular function was re-established only in the elderly group after an acute session of resistance exercise (Elderly group = 4.21±1.67 vs. 3.64±1.26 pre vs. post respectively). We conclude that physical exercise is an effective strategy to improve vascular function, regardless of the type, however there may be an age-dependent relationship with the type of exercise.
Cardiovascular diseases are the main cause of death worldwide and one of the main causes of these pathologies is systemic arterial hypertension. Aging is accompanied by pressure increases. The senescent is affected by sympathovagal imbalance, the deterioration of cardiac autonomic control is linear with age. However, studies show that treating hypertension with physical exercise has a great impact on reducing mortality from cardiovascular diseases. However, the mechanisms involved in postexercise hypotension are not clear. There is also a need for further studies on the effectiveness of physical exercise in reducing the risk of ischemic events, as well as in attenuating vascular dysfunction. In order to evaluate these physical exercise outcomes, the present study was divided into two phases, the first one conducted in Brazil with the objective of verifying the effect of an acute aerobic exercise session on the sympathovagal balance, blood pressure and vascular function of hypertensive subjects (study 1). And a second one conducted at Liverpool John Moores University aiming to evaluate the effect of acute resistance exercise in attenuating vascular dysfunction in young and elderly adults (study 2). Therefore, in study 1, hypertensive individuals aged between 40 and 55 and also between 60 and 80 years were recruited. Blood pressure was assessed by ambulatory blood pressure monitoring, heart rate variability and also carotid vascular reactivity. All individuals were submitted to cardiorespiratory assessment in order to establish the speed related to the first ventilatory threshold, and randomly to two sessions, one acute exercise session and a control session. Improvement in endothelial function was observed in elderly and young adults, which was measured by carotid vascular reactivity after an acute session of aerobic exercise [(Youth group= 1.41±1.78 vs. 3.04±1.20, pre vs post respectively) and (Elderly group = 0.31±1.92 vs. 2.27±1.43 pre vs post respectively)]. For study 2, healthy men aged between 20 and 40 and also between 50 and 70 years of age were recruited. Subjects underwent temporary ischemia reperfusion injury (IRI) in order to reduce vascular function. After ischemia reperfusion injury induction, subjects underwent three sessions (control, squat and pre-ischemic conditioning), in order to assess vascular function flow-mediated dilation (FMD) method was employed. Vascular function was re-established only in the elderly group after an acute session of resistance exercise (Elderly group = 4.21±1.67 vs. 3.64±1.26 pre vs. post respectively). We conclude that physical exercise is an effective strategy to improve vascular function, regardless of the type, however there may be an age-dependent relationship with the type of exercise.
Descrição
Citação
MONTREZOL, Fabio Tanil. Efeitos do exercício físico sobre a pressão arterial, variabilidade da frequência cardíaca e na função vascular de indivíduos com e sem hipertensão. 2021. 100 f. Tese (Doutorado em Ciências do Movimento Humano e Reabilitação) - Instituto de Saúde e Sociedade, Universidade Federal de São Paulo, Santos, 2021.