Combined Exercise Circuit Session Acutely Attenuates Stress-Induced Blood Pressure Reactivity in Healthy Adults

Introduction: Daily stress levels of population are increasing over the last decades. Frequent spouse to stress is considered an important risk factor for development of cardiovascular diseases. Other well documented risk factor for cardiovascular diseases is systemic hypertension which, in turn, has been related to elevated blood pressure reactivity (BPR) to stress. The exacerbated BPR may suggest a poor autonomic modulation due to an elevated sympathetic tone, condition that has been associated with medium to long-term cardiovascular complications. Also, some reports have demonstrated that individuals hyper-reactive to stress chronically increase their risk for psychological disorders such as anxiety, irritability and frustration. These feelings are associated to increased sympathetic tone induced chronic elevation in BP. Although the hemodynamic benefits of aerobic and resistance exercises had been documented in a variety of reports5, the acute effects of the aforementioned exercise modes combined in a circuit method on post-exercise BP, including the responses to cardiovascular stressor test need further investigations. Objective: To investigate the blood pressure (BP) responses to cardiovascular stressor test after a combined exercise circuit session at moderate intensity. Methods: Twenty individuals (10male/10fem; 33.4±6.9years; 70.2±15.8kg; 170.4±11.5cm; 22.3±6.8 %body fat) volunteered to randomly perform on different days: 1) Exercise session consisting of 3-laps in a circuit model in the following sequence: knee extension, bench press, knee flexion, rowing in the prone, squat, shoulder press and 5-min of aerobic exercise at 75-85% of age-predicted maximum heart rate and/or 13 in the Borg-Scale [6-20]. The sets of resistance exercise were composed by 15 repetitions with ~50% of one repetition maximum test and; 2) a control session without exercise. The systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured at resting and during 1h of recovery in both experimental sessions. After that, blood pressure reactivity (BPR) was evaluated using the Cold Pressor Test (a test with hand in the cold water during one minute). The hypotheses are that after doing the exercise session occur attenuation of blood pressure increase during the Cold Pressor Test compared to sitting without exercise (control session).