Hemodynamic mechanisms of the attenuated blood pressure response to mental stress after a single bout of maximal dynamic exercise in healthy subjects

F.J Neves,A.R.K Sales,A.C.L Nóbrega,B.M Silva,N.G Rocha,A.C.G Carvalho,J.D Rocha,R.R.T De Castro,T.G Thomaz

doi:10.1590/s0100-879x2012007500083

F.J Neves, A.R.K Sales + Show 7 more

Open Access

https://doi.org/10.1590/s0100-879x2012007500083

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Abstract

To determine the hemodynamic mechanisms responsible for the attenuated blood pressure response to mental stress after exercise, 26 healthy sedentary individuals (age 29 ± 8 years) underwent the Stroop color-word test before and 60 min after a bout of maximal dynamic exercise on a treadmill. A subgroup (N = 11) underwent a time-control experiment without exercise. Blood pressure was continuously and noninvasively recorded by infrared finger photoplethysmography. Stroke volume was derived from pressure signals, and cardiac output and peripheral vascular resistance were calculated. Perceived mental stress scores were comparable between mental stress tests both in the exercise (P = 0.96) and control (P = 0.24) experiments. After exercise, the systolic blood pressure response to mental stress was attenuated (pre: 10 ± 13 vs post: 6 ± 7 mmHg; P < 0.01) along with lower values of systolic blood pressure (pre: 129 ± 3 vs post: 125 ± 3 mmHg; P < 0.05), stroke volume (pre: 89.4 ± 3.5 vs post: 76.8 ± 3.8 mL; P < 0.05), and cardiac output (pre: 7.00 ± 0.30 vs post: 6.51 ± 0.36 L/min; P < 0.05). Except for heart rate, the hemodynamic responses and the mean values during the two mental stress tests in the control experiment were similar (P > 0.05). In conclusion, a single bout of maximal dynamic exercise attenuates the blood pressure response to mental stress in healthy subjects, along with lower stroke volume and cardiac output, denoting an acute modulatory action of exercise on the central hemodynamic response to mental stress.

Highlights

And physically stressful situations occur frequently throughout our lives and the capacity to respond to them, both in motor and physiological terms, are natural and necessary organic functions
The experimental protocol consisted of measurements of blood pressure response by beat-to-beat finger infrared plethysmography to a mental stress challenge both before and 1 h after a single bout of maximal dynamic exercise
There were no differences between the subjects included in the single bout of maximal dynamic exercise or in the control non-exercise experiment (P > 0.05)

Summary

Introduction

And physically stressful situations occur frequently throughout our lives and the capacity to respond to them, both in motor and physiological terms, are natural and necessary organic functions. The cardiovascular system is directly involved in the response to mental stress, suffering in exacerbated stressful conditions. Sympathetic nervous system activation and parasympathetic inhibition increase arterial pressure and heart rate, leading to increased myocardial oxygen consumption [1]. This is a physiological phenomenon, exacerbated responses of blood pressure confer an increased risk of developing hypertension [2,3]. Physical exercise promotes complex physiological responses of the cardiovascular system, which are dependent on the interaction between cardiac, vascular, and autonomic mechanisms, responsible for the maintenance of homeostasis [6,7].

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