Post-resistance exercise hypotension in hypertensive men: influence of captopril treatment

Author(s)

Andreia Cristiane Carrenho Queiroz

• Document type: Doctoral Thesis
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Escola de Educação Física e Esportes (EEFE/BT)
• Defense date: 2013-06-19

Examining board members

Cláudia Lúcia de Moraes Forjaz; Maria Claudia Costa Irigoyen; Marcos Doederlein Polito; Maria Urbana Pinto Brandão Rondon; Angelina Zanesco

• Advisor: Cláudia Lúcia de Moraes Forjaz

Abstract

A session of resistance exercise promotes post-exercise hypotension in hypertensive subjects (HT). Due to the cardiovascular alterations imposed by the disease, it is possible that HT present hypotensive mechanisms different from those observed in normotensive subjects (NT). Moreover, HT frequently receive antihypertensive medications that might affect post-exercise responses. The aim of this thesis was to evaluate, in HT men, the effects of resistance exercise session on blood pressure (BP) and its hemodynamic and neural mechanisms, comparing these effects with the responses observed in NT and verifying the effect of captopril use on these responses. Twelve HT (50±3 years) and 14 NT (44±3 years) participated in the study. HT were studied in two situations, after 4 weeks of placebo and captopril (3 x 50mg/day) administered in a crossover double-blind design. NT was studied only once without any medication. At each group/situation, subjects underwent 2 experimental sessions performed in a random order: Control (rest) and Exercise (6 resistance exercises, 3 sets until moderated fatigue, 50% of 1RM). Measurements were taken before and in 2 post-intervention moments (Post1 - between 30-80min and Post2 - after 7pm). Moreover, ambulatory BP was measured after the sessions. In Post1, systolic BP decreased similarly in all groups/situations (NT=-8±2; unmedicated HT=-13±2; medicated HT=-12±2mmHg). Diastolic BP also decreased, but this decrease was greater in unmedicated HT compared with NT (-9±1 vs. -4±1mmHg, respectively), and were similar in HT with and without medication. Regardless of group/situation, exercise promoted a decrease in cardiac output (CO) in some subjects and a reduction in systemic vascular resistance (SVR) in others. Stroke volume (SV) decreased (NT=-14±5; unmedicated HT=-11±5; medicated HT=-17±5ml) and HR increased (NT=13±3; unmedicated HT=13±2; medicated HT=13±2bpm) after exercise similarly in all groups/situations. Also similarly between groups/situations, cardiac sympathovagal balance increased (NT=+1,9±0,4, unmedicated HT=+1.4±0.3, medicated HT=+1,8±0,3) and BS decreased (NT=-5±1; unmedicated HT=-4±2; medicated HT=+3±1mmHg/bpm) post-exercise. In Post2, in all groups/situations, exercise did not affect any variable. In addition, ambulatory BP was similar after the control and exercise sessions in all group/situation. In conclusion, a single bout of resistance exercise session promotes post-exercise hypotension in the laboratory in NT and HT subjects receiving or not captopril, but this hypotensive effect is not maintained under ambulatory conditions. The magnitude of BP decrease is greater in non-medicated HT than in NT, and it was not changed by captopril. Autonomic and hemodynamic mechanisms of post-exercise hypotension are similar in NT and HT receiving medication or not. The hemodynamic determinant (CO or SVR) of post-exercise hypotension varies from one subject to another. However, BP reduction is accompanied by decrease in SV and an increase in HR that results from an increase in cardiac sympathovagal balance and decrease in BS (AU)

• FAPESP's process: 09/18219-3 - POST-RESISTANCE EXERCISE HYPOTENSION IN HYPERTENSIVE MEN: INFLUENCE OF CAPTOPRIL TREATMENT.
• Grantee: Andréia Cristiane Carrenho Queiroz
• Support Opportunities: Scholarships in Brazil - Doctorate