Efeito agudo do exercício físico na hemodinâmica de filhos de hipertensos

Abstract

INTRODUCTION: Normotensive individuals with hypertensive parents present higher levels of arterial pressure and peripheral vascular resistance. In hypertensive patients, it is known that a single exercise session is able to promote post-exercise hypotension and improve peripheral vascular resistance. However, it is unclear whether the same benefit is achieved by individuals with a positive family history of hypertension. OBJECTIVES: 1) Verify whether normotensive children of hypertensive have post-exercise hypotension. 2) Verify the acute effect of exercise on peripheral vascular resistance on normotensive children of hypertensive. METHODOLOGY: Thirteen normotensive children of hypertensive (age = 30±5 years old; BMI = 24±4 kg/m²; SBP = 98±11 mmHg; DBP = 62±7 mmHg; MBP = 74±8 mmHg) were submitted to 30 minute of exercise on a cycle ergometer of the upper limbs, in intensity of 40% to 60% of heart rate reserve, followed by one hour of recovery, called exercise session. Through Finometer Pro® equipment has captured the wave of blood pressure pulse. The forearm muscle blood flow and peripheral vascular resistance were evaluated by Venous Occlusion Plethysmography (Hokanson®). All variables were simultaneously recorded by period 5 minutes in the resting pre-exercise and by 4 periods of 5 minutes in recovery after exercise. Local peripheral vascular resistance was calculated by dividing the mean arterial pressure by the forearm muscle blood flow. Randomly, one control session without exercise was done. Two-way ANOVA was performed followed by Tukey post hoc and considered significant difference p <0.05. RESULTS: There was no post-exercise hypotension (p> 0.05). There was an increase in systolic blood pressure in the penultimate and the last 5 minutes of recovery (p <0.05), in diastolic blood pressure, in the first and the last 5 minutes of recovery (p <0.05) and in mean arterial pressure in the last five minutes of the recovery period (p <0.05), however, these increases occurred similarly in both sessions, control and exercise (p = 0.48, p = 0.73 and p = 0.54; respectively). Local peripheral vascular resistance was similar in the rest between exercise sessions and control (42 ± 9 vs. 38 ± 10 un, p = 0.99; respectively), during the all recovery period postexercise is showed significantly lower than in the rest (p <0.01) and compared to the control session (1st period: 17 ± 7 vs. 37 ± 10 un, p <0.01; 2nd period: 22 ± 8 vs. 39 un ± 12, p <0.01; 3rd period: 25 ± 8 vs. 42 ± 12 un, p <0.01; 4th period: 26 ± 6 vs. 42 ± 13 un, p <0.01; respectively). CONCLUSION: After a session of aerobic exercise, normotensive children of hypertensive do not have post-exercise hypotension, but reduce peripheral vascular resistance.